DESCRIPTION
ANTIFOULING COATING COMPOSITION, ANTIFOULING COATING FILM, AND
ANTIFOULING METHOD FOR SUBSTRATE
Technical Field
[0001] The present invention relates to a two-part
hydrolysable antifouling coating composition having a low
environmental load and a reduced impact on human body, and that
10 can impart excellent antifouling property, etc. to the substrate
surfaces of ships, underwater structures, fishing nets, fishing
gears and the like; and relates to an antifouling method for an
antifouling coating film and a substrate employing the two-part
hydrolysable antifouling coating composition
15 producing an antifouling substrate) .
Background Art
[0002] The substrate surfaces for ships,
(method of
underwater
structures, fishing nets, and the like which are exposed to water
for long term, are easily attached by various aquatic creatures
20 including animals as oysters, mussels and barnacles, plants as
sea weeds, and bacteria. Proliferation of such aquatic creatures
on the substrate surfaces increases the surface roughness of ship,
and therefore leading to the speed reduction, fuel cost increase,
and damage to the anticorrosive coating films applied on the
SF-2390 2
substrate surfaces, possibly resulting in deteriorated strength
and functionality as well as extremely shortened life time to
underwater structures. In addition, attachment and
proliferation of such aquatic creatures on fishing nets including
5 aquaculture nets and fixed nets may cause serious problems such
as oxygen deficiency mortality of caught fish because of the
obstruction on the mesh. Furthermore, attachment and
proliferation of aquatic creatures on seawater plumbing pipes for
thermal power, nuclear power plants, etc. may interfere with the
10 circulation of cooling water supply. To solve such problems,
research and development efforts have been directed at various
antifouling coatings to be applied on substrate surfaces so as
to prevent aquatic creatures from attaching.
[0003] As a conventional antifouling coating, an antifouling
15 coating composition employing a hydrolysable polyester resins as
a resin is known. Since polyester resins are produced by
esterification of dehydration condensation between acids and
alcohols, the resins are easily subjected to hydrolysis, excel
in antifouling properties, and can be readily absorbed into the
20 metabolism process of microorganisms through hydrolysis.
[0004] For example, Patent document 1 discloses an
antifouling coating using an aliphatic polyester as a hydrolysable
resin, the aliphatic polyester is prepared by copolymerizing one
or more of glycerin, ethylene glycol, and 1,4-butanediols with
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a polyester comprising succinic acid and 1,2-propylene glycol,
Patent document 2 discloses an antifouling coating comprising a
hydrolysable polyester resin obtained by reacting an oxyacid such
as lactic acid, polyvalent carboxylic acid containing no hydroxyl
5 group, and a polyhydric alcohol, Patent document 3 discloses a
hydrolysable polyester resin for an antifouling coating that is
composed mainly of an aliphatic polyester comprising a metal salt
of a hydroxyl carboxylic acid, and Patent document 4 discloses
a polyester resin for an antifouling coating, having excellent
10 coating suitability with an appropriate hydrolyzing rate,
obtained by copolymerizing C2-40 dicarboxylic acids and C2-40
glycols with glycolic acid, lactic acid, caprolactone, or the
like.
[0005] Also, Patent document 5 discloses an antifouling
15 coating composition comprising a resin having an acid value of
20-400, a metal-containing antifouling agent and a monobasic acid
compound having a carboxyl group, Patent document 6 discloses an
antifouling coating composition comprising a hydrolysable
polyester having carboxyl groups at both ends, Patent document
20 7 discloses an antifouling coating composition comprising a resin
obtained by reacting an acrylic resin with a divalent or more
-valent metal oxide, a polyester resin having an acid value of
50-200 mgKOH/g, and an antifouling agent, Patent document 8
discloses an antifouling anti-algae polyester-based resin
SF-2390 4
composition obtained by adding an antifouling agent to a
polybutylene terephthalate copolymer comprising
polytetramethylene glycol and isophthalic acid as copolymerizing
components, Patent document 9 discloses an antifouling coating
5 comprising a biocide and a binder polymer which is hydrolysable
with an acid functional polymer, and Patent document 10 discloses
an antifouling coating comprising a hydrolysable self-polishing
resin (an acrylic resin or polyester resin), cupric oxide, and
copper pyrithione. Patent document 11 discloses an antifouling
10 coating comprising a (meth) acrylic acid metal salt-based
copolymer and a triphenylboron-amine complex, and Patent document
12 discloses an antifouling coating comprising a copolymer having
a carboxyl group, a polyvalent metal compound, and an antifouling
agent.
15 Citation List
Patent Documents
[0006]
[Patent document 1] Japanese Unexamined Patent Application
Publication HEI No.7-166106
20 [Patent document 2] Japanese Unexamined Patent Application
Publication No. 7-082513
[Patent document 3] Japanese Unexamined Patent Application
Publication No. 8-176501
[Patent document 4] Japanese Unexamined Patent Application
SF-2390 5
Publication No. 7-53899
[Patent document 5] Japanese Unexamined Patent Application
Publication No. 9-132736
[Patent document 6] Japanese Unexamined Patent Application
5 Publication No. 11-255869
[Patent document 7] Japanese Unexamined Patent Application
Publication No.2000-248206
[Patent document 8] Japanese Unexamined Patent Application
Publication SHO No.57-128742
10 [Patent document 9] Japanese Unexamined Patent Application
Publication No. 2-196869
[Patent document 10] Japanese Unexamined Patent Application
Publication No. 10-298455
[Patent document 11] Japanese Unexamined Patent Application
15 Publication No. 11-323209
20
[Patent document 12] Japanese Unexamined Patent Application
Publication No.W02007-074656
Summary of the Invention
Problem to be Solved by the Invention
[0007] Recently, from the viewpoint of environmental
problems, it has been an important issue in the field of
antifouling coatings how to reduce volatile organic compound (VOC)
contents of coatings, in addition to providing prolonged
antifouling performance (long-term antifouling properties) and
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reducing re-coating operations.
[0008] However, Patent documents 1-11 preferable above do
not sufficiently research the issue on reducing the VOC. The
research conducted by the present inventors has found that the
5 conventional antifouling coatings employing polyester resins
must be improved in the following aspects.
[0009] Specifically, in such conventional antifouling
coatings, the resins having a viscosity suitable for coating
(especially when the molecular weight of resins is high) must be
10 produced by using a large amounts of solvent without exception.
Consequently, the coating materials having a viscosity for
practical use have high VOC contents, which is no longer
environmental friendly.
[0010] On the other hand, a research has been conducted on
15 how to lower the resin viscosity while reducing the usage of
solvents.
[0011] One of the measures includes, for example, lowering
the molecular weight of the polyester contained in coatings. In
this measure, it is possible to reduce the organic sol vent amounts
20 in coatings, however, the hydrolysis rate in seawater grows too
high, which disallows controlling the hydrolysis rate, thus,
deteriorating the long-term antifouling property. In terms of
a long-term antifouling property, a polyester resin for
antifouling coating having polylactic acid, polyglycolic acid,
SF-2390 7
etc. as monomers also cannot maintain the long-term antifouling
property because of too high hydrolysis rate.
[0012] In a monomer component of a resin, it is also possible
to lower the viscosity while reducing the sol vent usage by
5 increasing the component rate of the monomers (i.e., soft monomer)
such as ethylacrylate having a function that lowers the resin
viscosity and Tg for improving the flexibility. However, since
the Tg of the resin containing a large amount of soft monomer as
monomer component preferable above is low, the coating containing
10 such a resin lowers the drying characteristic (coating strength) .
15
20
Particularly, a coating comprising a resin having a low molecular
weight and a high component percentage of soft monomer as a monomer
component forms a coating film that is significantly hard to dry,
has a low strength and is still sticky.
[0013] Patent document 8 discloses an aspect of an
antifouling coating to be added with a polyester resin, cupric
oxide, and a zinc flower, however, the coating is hard to say a
hydrolysable coating and is difficult to keep the VOC value at
a lower level.
[0014] The resin used for the coating composition of Patent
document 10 forms an organic acid residue structure at the
side-chain end, hence, a metallic cross-linked body is not formed.
That is, the resin comprises relatively low molecular weight
comparing to a resin having a metallic cross-linked structure.
SF-2390 8
For that reason, a coating composition comprising this resin may
be able to reduce the usage of solvents, lowers the VOC value,
and maintain the coating workability to a certain degree. However,
the composition uses polyester of low molecular weight, the
5 hydrolysis rate in seawater becomes too high to control, still
leaving a room for improvement with regard to the long-term
antifouling property and coating film strength.
[0015] Patent document 11 discloses a coating composition
free from copper compound in which a polymer having a metallic
10 cross-linked structure is used as a resin. However, since the
resin comprises a metallic cross-linked structure, the resin bears
extremely high molecular weight comparing to a resin having no
metallic cross-linked structure. That is, the viscosity of the
resin is fundamentally high and the coating viscosity becomes even
15 higher if the low VOC is intended.
20
[0016] Patent document 12 discloses a low VOC hydrolysable
antifouling coating employing an acrylic resin, however, there
is still a room for improvement in the viscosity of the coatings
and the drying characteristic of the coating films.
[0017] The antifouling coating films containing copper or
copper compound (especially cupric oxide) exhibit remarkable
discoloration by ultraviolet ray and moisture. In addition to
the discoloration, a crack may occur in the coating films when
the coating films are exposed to ultraviolet ray and moisture for
SF-2390 9
a long term. Especially, the crack poses a serious problem, may
lead to flaking, and thus, shortens the expected service year.
[0018] To eliminate such copper or copper compound related
problems, an antifouling coating composition free from copper or
5 copper compound is proposed, however such antifouling coating
compositions are added with a large amount of various organic
antifouling agents in order to maintain the antifouling property,
which generated various problems including extremely high coating
viscosity, low storage stability, and even deteriorated coating
10 film hardness (strength). Therefore, it was difficult to realize
a low VOC with one-part coating composition employing the
conventional hydrolysis resin.
[0019] As mentioned above, the low voc and the
characteristics such as long term antifouling property establish
15 a trade-off relation, a polyester antifouling coating, free from
copper and copper compounds (especially, cupric oxide), that
satisfies these characteristics at the same time has not been
achieved yet.
[0020] As a result of the research on the above-mentioned
20 problems of the prior art, the inventors of the present invention
found that the adoption of the first component and the second
component having a specific composition in the two-part
hydrolysable antifouling coating composition will resolve the
above-mentioned copper or copper compound related problems,
5
SF-2390 10
maintain the coating film properties such as a long-term
antifouling property, and realize low VOC which was extremely
difficult with the conventional copper-compound-free
composition.
[0021] The object is to provide: a two-part hydrolysable
antifouling coating composition having such features as
preventing discoloration due to ultraviolet ray or moisture and
cracking by excluding copper or copper compound (e.g., cupric
oxide), simultaneously maintaining a low VOC and a long-term
10 antifouling property at a high level, and forming an antifouling
coating film excellent in mechanical strength for a long-term;
and a production method of an antifouling coating film and an
antifouling substrate employing the two-part hydrolysable
antifouling coating composition.
15 Means for Solving the Problem
[0022] The two-part hydrolysable antifouling coating
composition comprises two liquids including: a first component
containing a polyester resin having a solid content acid value
of 50-200 mgKOH/g and a hydroxyl value of 100 mgKOH/g or less,
20 and having a viscosity of 500 mPa· s or less at 25 ·c; and a second
component in paste form containing a zinc oxide, and based on the
total amount of the first and the second components, the content
of volatile organic compound is 400g/L or less, and the components
are free from copper and copper compound.
5
10
SF-2390 11
[0023] In the two-part hydrolysable antifouling coating
composition of the present invention, the weight average molecular
weight of the polyester resin, measured by the gel permission
chromatography, is preferred to be 5,000 or less.
[0024] In the two-part hydrolysable antifouling coating
composition of the present invention, the content of zinc oxide
in the second component is preferred to be 10-500 parts by weight
relative to 100 parts by weight of the polyester resin (solid
content).
[0025] It is further preferred to contain rosin and/or a
rosin derivative in the two-part hydrolysable antifouling coating
composition of the present invention.
[0026] It is further preferred to contain an antifouling
agent in the two-part hydrolysable antifouling coating
15 composition of the present invention.
[0027] It is further preferred to contain a zinc pyri thione
as an antifouling agent in the two-part hydrolysable antifouling
coating composition of the present invention.
[0028] It is preferred to contain at least one plasticizer
20 selected from a group consisting of a chlorinated paraffin,
petroleum resins, ketone resins, tricresyl phosphate, polyvinyl
ethyl ether, dialkyl phthalate, and (meth) acrylic polymers in
the two-part hydrolysable antifouling coating composition of the
present invention.
,, SF-2390 12
[0029] It is further preferred to contain an extender pigment
(except for zinc oxide) in the two-part hydrolysable antifouling
coating composition of the present invention.
[0030] It is further preferred to contain a pigment
5 dispersant in the two-part hydrolysable antifouling coating
composition of the present invention.
10
[0031] It is further preferred to contain a color pigment
in the two-part hydrolysable antifouling coating composition of
the present invention.
[0032] It is further preferred to contain a dehydrating agent
in the two-part hydrolysable antifouling coating composition of
the present invention.
[0033] The two-part hydrolysable antifouling coating
composition of the present invention comprises two liquids as:
15 a first component including a reaction mixture (A) having a
polyester resin (a3) obtained by polycondensation of an acid
component (a1) and a polyvalent alcohol component (a2); and a
second component including a zinc oxide (B), the acid value and
the hydroxyl value of the solid content in the reaction mixture
20 (A) are 50-200 mgKOH/g and 100 mgKOH/g or less, respectively,
copper and copper compound are substantially not included in the
two-part hydrolysable antifouling coating composition, and the
content of the volatile organic compound is 400 g or less per
SF-2390 13
lL of the two-part hydrolysable antifouling coating composition.
[0034] The antifouling coating film of the present invention
is formed by hardening any of the above two-part hydrolysable
5 antifouling coating compositions.
[0035] The antifouling method for substrate of the present
invention comprises coating or impregnating any of the above
two-part hydrolysable antifouling coating compositions onto a
substrate, followed by hardening the substrate to form an
10 antifouling coating film.
15
[0036] Also, the two-part hydrolysable antifouling coating
composition of the present invention may be simply referred to
as "two-part antifouling coating composition" or "antifouling
coating composition", in some cases. In addition, the term of
"two-part hydrolysable antifouling coating
composition" ("antifouling coating composition" or "two-part
antifouling coating composition") may be used for indicating a
state of storage or transportation without mixing the two
components contained as well as a state of mixing the first and
20 the second components in the two-part hydrolysable antifouling
coating composition. Particularly, the latter mixing state is
also referred to as "mixture coating". The two-part hydrolysable
antifouling coating composition of the present invention obtained
by mixing the above-mentioned first and second components (mixture
SF-2390 14
coating) is applied on an object (substrate) to form an antifouling
coating film.
[0037] The two-part hydrolysable antifouling coating
composition of the present invention is a two-liquid type
5 antifouling coating composition to be mixed and used with the
above-mentioned first and second components, which forms a
hydrolysable metallic cross-linked body by the reaction between
a polyester resin component and a zinc oxide following to the
mixing of the first component and the second component.
10 Consequently, discoloration by ultraviolet ray and moisture is
prevented and the VOC value can be greatly reduced without
degrading the storage stability and coating workability to achieve
a stable hydrolysis mechanism, resulting in a hydrolysable
antifouling coating composition having a long-term coating film
15 grindabili ty.
[0038] In addition, the polyester resin contained in the first
component is a high oxidation polyester resin, and by including
the resin in the first component, the crosslinking reaction
between a zinc ion and a carboxylic ion of a polyester resin is
20 sufficiently improved when the first and second components are
mixed, which improves such properties as coating film drying
characteristic, coating film strength, coating film
physicalities, and hydrolysis (self polishing characteristic and
antifouling property) . That is, the antifouling coating
'
SF-2390 15
composition of the present invention maintains the antifouling
property for a long-term and also can control drying
characteristic and hydrolysis characteristic associated with
the metallic crosslinking by controlling the acid value.
5 Advantageous Effects of Invention
[0039] According to the present invention, it is possible
to provide a low VOC high-solid type hydrolysable antifouling
coating composition well-balanced in various performance aspects
and capable of forming an antifouling coating film, which prevents
10 discoloration by ultraviolet ray, moisture, or the like and
cracking; reducing the environmental load and the impact on human
body; and excels in coating operation, drying characteristic,
long-term antifouling property (consumption property and
stationary antifouling property), and mechanical strength
15 regardless low VOC.
[0040] According to the invention, it is also possible to
provide an antifouling coating film having an excellent long-term
antifouling property and mechanical strength.
[0041] Furthermore, according to the present invention, it
20 is possible to provide an antifouling method for substrate
(production method of antifouling substrate), which can prevent
fouling of substrate surfaces of underwater structures, ship outer
platings, fishing nets, fishing gear, and the like for a long-term.
Brief Description of the Drawings
5
SF-2390 16
[0042] Fig.1 is a illustration diagram showing the
evaluation criteria in a coating film drying characteristic test
(wood block pressing test) in the Examples.
Description of the Preferred Embodiments
[0043] Preferred embodiments of the present invention will
now be preferable in detail.
[0044] [Two-part hydrolysable antifouling coating composition]
A two-part hydrolysable antifouling coating composition of
the present invention is a two-part antifouling coating
10 composition including the first component and the second component
preferable below, in which the content of volatile organic
compound is 400 g/L or less, and is 400 g or less per 1 L of the
two-part hydrolysable antifouling coating composition, and
excluding copper or copper compound.
15 [0045] A first component: a liquid including a polyester
resin having a solid content acid value of 50-200 mgKOH/g and a
hydroxyl value of 100 mgKOH/g or less, and preferably having a
viscosity of 500 mPa·s or less at 25·c.
A second component: a liquid containing a zinc oxide (e.g.,
20 paste)
If the first component is a liquid including a reaction mixture
(A) having a polyester resin (a3) prepared by polycondensation
of an acid component ( a1) and a polyvalent alcohol component ( a2) ,
the two-part hydrolysable antifouling coating composition of the
SF-2390 17
present invention is a two-part antifouling coating composition
consisting of the first and the second components preferable below,
in which the content of a volatile organic compound is 400 g/L
or less relative to the total amount of the first and second
5 components (that is, 400 g or less per 1 L of the two-part
hydrolysable antifouling coating composition), and substantially
excluding copper or copper compound.
[0046]. A first component: a liquid including a reaction
mixture (A) having a polyester resin (a3) obtained by
10 polycondensation of an acid component ( a1) and a polyvalent
alcohol component (a2) .
A second component: a liquid containing a zinc oxide (B)
The acid value and the hydroxyl value of the solid content in the
reaction mixture (A) are 50-200 mgKOH/g and 100 mgKOH/g or less,
15 respectively.
[0047] For forming a coating film on a substrate, the
two-part hydrolysable antifouling coating composition of the
present invention is used by mixing the first and the second
components. In mixing the first and the second components, a
20 reaction represented by the following formula may progress by the
polyester resin (the polyester resin (a3) contained in the
reaction mixture (A) if the first component includes a reaction
mixture (A)) contained in the first component and the zinc oxide
(B) contained in the second component.
SF-2390 18
[0048] Before the mixing, the polyester resin (the polyester
resin (a3) contained in the reaction mixture (A) if the first
component includes a reaction mixture (A)) contained in the first
component includes a carboxyl group as a side chain (see (A) below) .
5 In the preparation of mixture coatings by mixing the first and
the second components, an H of a carboxylic group in a particular
polyester resin (the polyester resin (a3) contained in the
reaction mixture (A) if the first component includes a reaction
mixture (A)) removes to generate a carboxylic ion (COO-) (see (B)
10 below). In addition, the carboxyl ion and a zinc oxide (B) derived
15
from the second component undergo a cross-linking reaction as (C)
below to form a hydrolysable metallic cross-linked body.
[0049] [Chemical formula 1]
(A)
Polyester chain
~,....,....,"-4 .. w •• -·.·.;...
COOH
COOH
~,_·.~L. ...... .., ...
Polyester chain
Before mixing
(B}
Polyester chain
~l ....... ~_,-A...,..._ ........
C=O
I o·
o-
C' =o
,. ... ,. "#i" Ai'llo 1 ..... +++ '"''"'""·
Polyester chain
After mixing
(generation of
carboxyl ion)
Chemical reaction formula (I)
+ ZnO
(C)
Polyester chain
~ ..... .,..f''''' .. '*+-~~~
C=O
~
Q'
:tiJ
6 I
C=O
~L----
Polyester chain
After mixing
(formation of hydrolysable
metallic cross-linked body)
[0050] As used herein, "free from copper and copper compound"
represents "substantially free from copper and copper compound",
SF-2390 19
and more particularly, it represents an aspect in which a two-part
coating composition completely excluding copper or copper
compound (content: 0 Wt%) , and another aspect in which a mixture
coating prepared by mixing the first and the second components
5 contains very small amount of (e.g., 100 ppm or less, specifically
10-100 ppm) copper and/or copper compound so that discoloration
by ultraviolet ray or moisture and generation of cracks on the
coating films by long-term exposure to ultraviolet ray and
moisture, and the like never occur. In regard to the latter aspect,
10 the content of copper or copper compound depends on the condition
that affects discoloration and generation of fine particles (e.g.,
temperature and pH), the content need be properly adjusted in
accordance with the conditions. From the viewpoint of completely
preventing the above-mentioned copper or copper compound related
15 discoloration and the generation of cracks, it is preferred to
exclude copper or copper compound (content: 0 Wt%).
[0051] From the viewpoint of favorable coating workability,
the antifouling coating composition of the present invention is
preferred to have a 20 Poise(20 dPa·s) or less for the viscosity
20 (viscosity of the mixture coating) (to be measured immediately
after the preparation at 23 ·C) of the coating prepared by mixing
the first and the second components and is preferred to have 5-20
Poise(5-20 dPa·s) from the viewpoint of the room temperature
coating workability, sufficient coating time (usable time), the
5
SF-2390 20
prevention of flowing the coating, etc. The viscosity preferable
herein is a value measured by using a Rion viscosimeter (RION CO.,
LTD VISCOTESTER VT-04 F for high viscosity, 1st rotor) after
adjusting the mixture coating to 23·c.
[0052] The "solid content" of particular polyester resin
("polyester resin (solid content)") used herein represents a
residue obtained by weighing lg of the polyester resin on a flat
bottom plate, spreading the resin evenly using a wire of known
weight, and drying the resin for one hour at 125 ·c. If the first
10 component contains a reaction mixture (A), the subject for the
solid content acid value and hydroxyl value can be the "solid
content" of the reaction mixture (A) ("reaction mixture (A) (solid
content)") . The "solid content" of the reaction mixture (A)
represents a residue obtained by weighing lg of the reaction
15 mixture (A) on a flat bottom plate, spreading the mixture evenly
using a wire of known weight, and drying the mixture for one hour
at 125 ·c.
[0053] The "acid value of the solid content" and the
"hydroxyl value of the solid content" in the polyester resin (the
20 reaction mixture (A) when the first component contains the
reaction mixture (A)) may be simply referred to as "solid content
acid value" and "solid content hydroxyl value".
[0054] Below explains each component.
[0055] [First component]
t
SF-2390 21
A first component of a two-part hydrolysable antifouling
coating composition of the present invention contains a polyester
resin having a solid content acid value of 50-200 mgKOH/g and a
hydroxyl value of 100 mgKOH/g or less, and having a viscosity of
5 50 0 mP a · s or 1 e s s at 2 5 ° C .
10
[0056] Specifically, the first component is a liquid
including a reaction mixture (A) as an essential component that
contains a polyester resin (a3) prepared by polycondensation of
an acid component (al) and a polyvalent alcohol component (a2).
[0057] The first component may include any component
preferable later in accordance with a purpose desired. However,
it is preferable that the first component substantially does not
contain a ZnO in order not to form a hydrolysable metallic
cross-linked body in the first component before being mixed with
15 the second component. The statement "substantially does not
contain a ZnO" preferable herein represents that a minimum amount
of ZnO can be allowed to contain in the first component unless
the workability remarkably deteriorates when mixing the first and
second components for coating even if the viscosity of the first
20 component rises by the hydrolysable metallic cross-linked body
formed by ZnO. It is more preferable that the first component
is free from ZnO in-the first component in order to completely
prevent forming a hydrolysable metallic cross-linked body before
being mixed with the second component.
5
SF-2390 22
[0058]
The polyester resin contained in the first component can
be prepared by polycondensation of the acid component (al) and
the polyhydric alcohol component (a2).
[0059] The reaction mixture (A) allowed to be contained in
the first component includes a preparation obtained by
polycondensation of the acid component (a1) and the polyhydric
alcohol component (a2) , which includes a polyester resin (a3),
and in many cases, includes a unreacting monomer ( (a1) and (a2)),
10 oligomer, solvent, catalyst, or the like. The reaction mixture
(A) is usually used as a first component directly.
[0060] The acid component (a1) is not particularly limited
to any as long as the component is a polybasic acid (divalent or
more-valent carboxylic acid), alkyl ester thereof, or acid
15 anhydride thereof, the polybasic acid includes two or more
carboxyl groups in one molecule, the carboxyl group performs
polycondensation reaction with the OH group of the polyhydric
alcohol component (a2) preferable later.
[0061] The acid component (a1) includes: an aromatic
20 dicarboxylic acid such as a terephthalic acid, isophthalic acid,
phthalic acid, and naphthalene dicarboxylic acid; an aliphatic
carboxylic acid such as an adipic acid, sebacic acid, azelaic acid,
succinic acid, haimicc acid, 1, 6-cyclohexane dicarboxylic acid;
a carboxylic acid of trivalent or more -valent (polybasic acid)
SF-2390 23
such as a trimelli tic acid and pyromelli tic acid; a low alkyl ester
thereof (e.g., Cl-C4 alkyl ester); or an acid anhydride of these.
[0062] The dibasic acids such as an aromatic dicarboxylic
acid and a saturated aliphatic dicarboxylic acid may be used in
5 one type alone or two types or more. Moreover, a trivalent or
more -valent polybasic acid may be used in one type alone or two
types or more.
[0063] A polyhydric alcohol component (a2) represents an
alcohol (bivalent or more -valent) having two or more hydroxyl
10 groups (OH groups) in one molecule.
15
20
[0064] A polyhydric alcohol component (a2) includes: an
ethylene glycol, propylene glycol, 1,2-propanediol,
1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl
glycol, 1,5-pentanediol, 1,6-hexanediol, 3-methy pentanediol,
diethylene glycol, 1,4-cyclohexanedimethanol,
3-methyl-1,5-pentanediol, 2-methyl-1,3-propanediol,
2,2-diethyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol,
hydrogenated bisphenol A, ethylene oxide addition product or
propylene oxide addition product for bisphenol A, bivalent or more
-valent polyhydric alcohol such as trimethylolethane,
trimethylolpropan, glycerins, and pentaerythritols. These
polyhydric alcohol components (a2) may be used in one type alone
or two types or more. A hydroxyl acid such as dimethylol propionic
acid can be subjected to a polycondensation reaction with the
SF-2390 24
above-mentioned acid component (a1) and polyhydric alcohol
component (a2).
[0065] A monocarboxylic acid such as benzoic acid and
p-t-butyl benzoic acid can be subjected to a polycondensation
5 reaction with the acid component ( a1) and polyhydric alcohol
component (a2).
[0066] From the viewpoint of exhibiting an excellent
reactivity with a zinc oxide (a hydrolysable metallic cross-linked
body can be formed easily) in spite of difficulty in viscosity
10 rise when mixing the first and second components, the content of
a constitutional unit derived from the above-mentioned acid
component (a1) in the polyester resin (the polyester resin (a3)
if the first component includes a reaction mixture (A)) (100
weight%) contained in the first component is preferred to be 5-95
15 weight %, further preferred to be 10-90 weight %, and still further
preferred to be 20-80 weight %.
[0067] The content of a constitutional unit derived from the
above-mentioned polyhydric alcohol component (a2) in the
polyester resin (the polyester resin (a3) if the first component
20 includes the reaction mixture (A)) (100 weight%) contained in
the first component is preferred to be 5-95 weight %, further
preferred to be 10-90 weight %, and still further preferred to
be 20-80 weight %.
[0068] In preparation of polyester resin, as the preparation
SF-2390 25
is performed by proceeding a polycondensation reaction
(esterification reaction or transesterification) , the
above-mentioned acid component (al) and a polyhydric alcohol
component (a2) are mixed, and well-known production method such
5 as a fusion method, and a solvent method using toluene, xylene
or others (reflux method) is suitably adopted. Under the
condition of reduced pressure and in the
polycondensation reaction is performed with uncatalyzation or
under the presence of a catalyst such as antimony trioxide,
10 germanium oxide, and N-butyl titanate.
[0069] The viscosity of the reaction mixture (A)
(immediately after preparation) at 25°C is preferred to be
500mPa · s or less, further preferred to be 100-SOOmPa · s, and still
further preferred to be 200-400mPa·s. If the viscosity exceeds
15 500mPa · s, it is difficult to exhibit a favorable coating
workability even maintaining the content of the volatile organic
compound (VOC) at a low level, for example, 400g or less per lL
of a two-part hydrolysable antifouling coating composition. The
viscosity (mPa·s) of the above-mentioned polyester resin (A) at
20 25°C is a value measured withE type viscometer (Toki Sangyo Co.,
Ltd, Model No. TV-22 viscometer) at 25°C.
[0070] It is preferable that the polyester resin contained
in the first component includes polyester resin having a weight
average molecular weight (Mw) of 5,000 or less. If the first
SF-2390 26
component includes the reaction mixture (A) , it is preferable that
the reaction mixture (A) includes a polyester resin (a3) having
a weight average molecular weight (Mw) of 5,000 or less. The
weight average molecular weight is preferred to be 4, 000 or less,
5 and is further preferred to be 3, 000 or less. If the weight average
molecular weight exceeds 5,000, the viscosity of the polyester
resin becomes high, and becomes excessively high when mixing the
10
15
first and the second components. That is, for an excellent
coating workability, the viscosity must be lowered with sol vents,
which tends to increase the VOC amount. Therefore, it is
preferable that the weight average molecular weight is 5,000 or
less. If it is less than 50 0, the coating film becomes still sticky
after drying because of the low molecular weight, so that the
weight average molecular weight is preferred to be 500 or more.
[0071] The weight average molecular weight of the polyester
resin is a value measured by the gel permeation chromatography
(GPC) using a standard polystyrene calibration curve based on the
following condition.
( GPC condition )
20 Pump: manufactured by Hitachi L-6200
Column: Hitachi Chemical Gel Pack GL-420, GL-430, and GL-440
Eluent solvent: Tetrahydrofuran
[0072] The solid content acid value of the polyester resin
is 50-200 mgKOH/g, and is preferred to be 80-150 mgKOH/g, and still
SF-2390 27
further preferred to be 90-110 mgKOH/g. If the first component
includes the reaction mixture (A), the above-mentioned solid
content hydroxyl value is the solid content hydroxyl value of the
reaction mixture (A). That is, the solid content acid value of
5 the reaction mixture (A) is 50-200 mgKOH/g, and is preferred to
be 80-150 mgKOH/g, and is still further preferred to be 90-110
mgKOH/g. If the above-mentioned solid content acid value is less
than 50 mgKOH/g, the drying characteristic of the coating film
deteriorates because of the slow reaction between the polyester
10 (a3) and the zinc oxide (a hydrolysable metallic cross-linked body
is difficult to form) when mixing the first and the second
components. If the above-mentioned solid content acid value
exceeds 200 mgKOH/g, such a defect as coating film crack occurs.
The above-mentioned solid content acid value can be measured by
15 a titration with potassium hydroxide (KOH) .
[0073] The solid content hydroxyl value of the polyester
resin is 100 mgKOH/g or less, and is preferred to be 50 mgKOH/g
or less, and still further preferred to be 20 mgKOH/g, and is most
preferred to be 10 mgKOH/g or less. If the first component
20 includes the reaction mixture (A), the above-mentioned solid
content hydroxyl value is the solid content hydroxyl value of the
reaction mixture (A). That is, the solid content hydroxyl value
of the reaction mixture (A) is 100 mgKOH/ g or less, and is preferred
to be 50 mgKOH/g or less, and still further preferred to be 20
SF-2390 28
mgKOH/g or less, and is most preferred to be 10 mgKOH/g or less.
If the above-mentioned solid content hydroxyl value exceeds 100
mgKOH/g, and if rosin or a petroleum resin is contained, the
compatibility between these components and the polyester resin
5 (a3) declines, and when a coating film is formed, the appearance
and the water resistance for the coating film deteriorate.
10
[0074] Each of the above-mentioned solid content acid values
can be adjusted to each numerical value within the above range
employing known means.
[0075] For example, these include: an acid end polyester
obtained by introducing an acid to the polyester resin (the
polyester resin (a3) contained in the reaction mixture (A) when
adjusting the solid content acid value of the reaction mixture
(A) ) at its end using a dibasic acid; and a polybasic acid
15 degeneration polyester obtained by degenerating a polyester resin
using a polybasic acid.
20
[0076] Such an acid end polyester, for example, is prepared
by mixing a dibasic acid and a bivalent alcohol, and running on
a polycondensation reaction (esterification reaction or
transesterification) . The above-mentioned polybasic acid
degeneration polyester, for example, is prepared by introducing
a polybasic acid (trimellitic anhydride and others) to the main
chain of the polyester to produce degeneration with the polybasic
acid after synthesizing the polyester. A preparation method for
SF-2390 29
a polybasic acid degeneration polyester also includes introducing
a polybasic acid to the main chain at the same time the
polycondensation reaction between the acid and alcohol components,
however, the method for adding a polybasic acid to the polyester
5 main chain after synthesizing the polyester results in more
reduced gels and thickenings, which is easier to regulate the
reaction. It is allowed to introduce a polybasic acid such as
a trimelli tic anhydride or the like alone, however, the viscosity
tends to rise because of higher polarity due to the increased
10 localization of carboxyl group. Therefore, it is further
preferred to use a monocarboxylic acid, a dicarboxylic acid, and
a polybasic acid together.
[0077] To make the above-mentioned solid content hydroxyl
value to 100 mgKOH/g or less, it is possible to adjust the number
15 of OH group by adjusting the mixing ratio of the monomer component
of the polyester resin (for example, (al), (a2), or any other
monomer component used for the preparation of the reaction mixture
(A) if the first component includes the reaction mixture (A)),
and also possible by adding a monocarboxylic acid after
20 polycondensation reaction and reacting the OH group of the
polyester resin with the carboxylic group of the carboxyl acid.
[0078] Because of low viscosity, the hydroxyls tend to
increase by lowering the molecular weight of the polyester resin,
however, the hydroxyl value can be adjusted by reacting a hydroxyl
SF-2390 30
and a carboxyl group such as monocarboxylic acid using a
monocarboxylic acid such as benzoic acid when preparing a
polyester resin. For example, if the first component contains
the reaction mixture (A), the hydroxyl value can be adjusted by
5 putting a monocarboxylic acid such as benzoic acid subjected to
a polycondensation reaction together with ( al) and ( a2) in order
to cause the hydroxyl to react with a carboxyl group such as
monocarboxylic acid when preparing th~ reaction mixture (A) .
[0079] [Second component]
10 A second component of a two-part hydrolysable antifouling
15
coating composition of the present invention is a liquid (e.g.,
a paste) including a zinc oxide (also referred to as zinc oxide
(B) ) and may further contain any component preferable later as
required.
[0080] The zinc oxide contained in the second component is
an active pigment, and if the first and the second components are
mixed, the zinc oxide functions as a hardener in that the zinc
oxide reacts with a carboxyl group of a polyester resin (polyester
resin (a3) when the first component contains the reaction mixture
20 (A) ) as above chemical equation (I) to form a metallic salt
cross-linking, thus, functioning as a hardener.
[0081] When the zinc oxide reacts with the carboxylic group
of the polyester resin, a -coo- group (carboxyl ion) which is a
residue of the carboxylic group of the polyester resin from which
SF-2390 31
an hydrion is removed, is formed, and a hydrolysable metal salt
cross-linked body (e.g., -COO· ·Zn2+· ·OOC-) is formed by the metal
ion Zn2+ derived from the zinc oxide (B). The hydrolysable
metallic salt cross-linked body hydrolyzes easily and exhibits
5 stable hydrolysis reaction (low fluctuation of hydrolysis rate
with time). That is, the coating composition of the present
invention can form a coating film that demonstrates a long-term
coating film grindability (excellent in long-term antifouling) .
By adopting a two-part reaction type, even under a low temperature,
10 and even if the content of volatile organic compound is set to
400g or less per lL of the two-part hydrolysable antifouling
coating composition, a coating viscosity practical for coating
(excellent in coating operation) can be maintained.
[0082] For the presence or absence of the reaction between
15 a zinc ion derived from the zinc oxide contained in the second
component and a carboxyl group of a polyester resin, for example,
it may be confirmed by checking the change of the coating hue before
and after the mixing of the first and second components, or could
be confirmed by the increase of viscosity the mixed coating with
20 time.
[0083] Various particle sizes are used for the zinc oxide
(B) contained in the second component. Rather than using a zinc
oxide having a large particle size, using a fine particle zinc
oxide whose particle size is lpm or less such as an active zinc
SF-2390 32
oxide facilitates a cross linking reaction (a reaction for forming
a hydrolysable metallic salt cross-linked body) between the
carboxyl group of the polyester resin and the zinc ion derived
from a zinc oxide (B), which is preferable in that it improves
5 the coating film hardness in a short time, and exhibits a
damage-resistance property of the coating film at an early stage.
[0084] The content of the zinc oxide in the second component
is preferred to be 10-500 parts by weight, and is further preferred
to be 50-300 parts by weight, relative to solid content of 100
10 parts by weight of the polyester resin contained in the first
component. If the first component contains the reaction mixture
(A), the content of the zinc oxide in the second component is
preferred to be 10-500 parts by weight, and is further preferred
to be 50-300 parts by weight, relative to the solid content of
15 100 parts by weight of the reaction mixture (A) . If the content
is less than 10 parts by weight, the coating property such as
hardenability and coating film strength tends to deteriorate, and
if the content exceeds 500 parts by weight, the coating property
tends to be poor because of generation of cracking and the like.
20 [0085] [Optional components]
Below explains optional components. An optional component
may be mixed into a first component and/or a second component,
or may be added to a coating being mixed with the first and second
components, or the resultant coating mixed with the first and
SF-2390 33
second components.
[0086] <(C) Rosin and rosin derivative>
From the viewpoint of preferable conformity with pigment
components that leads to the improvement of liquidity and lower
5 viscosity, and that of a long time maintainability of antifouling
property in that an antifouling agent (D) can be eluted smoothly
on a coating film formed by the antifouling coating composition
provided that the antifouling coating composition contains an
antifouling agent (D) preferable later, the antifouling coating
10 composition of the present invention may further include rosin
and/or a rosin derivative (C). Rosin includes gum rosin, wood
rosin, toll rosin, and the like. A rosin derivative includes
hydrogenation rosin, polymerization rosin, rosin maleate,
aldehyde degeneration rosin, rosin metal salt, rosin amine, and
15 the like. Rosin and/or rosin derivative can be used in one type,
or in combination with two or more types. Rosin and/or a rosin
derivative (C) may be contained in the first or second component,
or added into a compound having the first and second components
mixed, however, it is preferred to be added into the second
20 component.
[0087] The content of the rosin and/or the rosin derivative
is preferred to be 0.5-300 parts by weight, and is further
preferred to be 0.5-200 parts by weight, and is most preferred
to be 0.5-150 parts by weight relative to the solid content of
SF-2390 34
100 parts by weight of polyester resin contained in the first
component.
[0088] If the first component includes the reaction mixture
(A), the content of the rosin and/or the rosin derivative is
5 · preferred to be 0. 5-300 parts by weight, and is further preferred
to be 0. 5-200 parts by weight, and is most preferred to be 0. 5-150
parts by weight relative to the solid content of 100 parts by weight
of the reaction mixture (A) .
[0089] If the above-mentioned content is less than 0. 5 parts
10 by weight, the coating viscosity tends to rise, and if the content
exceeds 300 parts by weight, the coating property tends to
deteriorate because of occurrence of cracking and the like.
[0090] <(D) Antifouling agent>
The antifouling coating composition of the present
15 invention may further contain an antifouling agent (however,
excluding a copper compound such as copper and cuprous oxide;
hereinafter referred to as "antifouling agent (E)") • The
antifouling agent (D) is not especially limited to any as long
as the agent excludes a copper and a copper compound, and both
20 organic and inorganic antifouling agents are accepted. For
example, as an antifouling agent (D), the following substances
may be used: metallic pyrithiones such as zinc pyrithione;
4,5-dichloro-2-n-octyl-4-isothiazoline-3-one;
2-methylthio-4-t-butylamino-6-cyclopropylamino-s-triazine;
•
SF-2390 35
2-(p-chlorophenyl)-3-cyano-4-bromo-5-trifluoromethylpyrrole;
N,N'-dimethyl-N'-tolyl-(N-fluorodichloromethylthio)
sulfamide; and pyridine-triphenylborane. Considering an
antifouling property in stationary condition, the following
5 substances are preferred to use as an antifouling agent (D): zinc
pyrithione; 4,5-dichloro-2-n-octyl-4-isothiazoline-3-one;
2-methylthio-4-t-butylamino-6-cyclopropylamino-s-triazine;
and 2-(p-chlorophenyl)-3-cyano-4-bromo-5-trifluoromethyl
pyrrole. Considering a long-term antifouling property to animal
10 species especially such as barnacles, it is preferred to combine
2-(p-chlorophenyl)3-cyano-4-bromo-5-trifluoromethylpyrrole
and another antifouling agent (D) excluding that substance. It
is preferred to contain an antifouling agent (D) in the second
component.
15
20
[0091] In the antifouling coating composition of the present
invention, the content of the antifouling agent (D) is preferred
to be 5-600 parts by weight, and is further preferred to be 10-500
parts by weight, relative to solid content of 100 parts by weight
of polyester resin contained in the first component.
[0092] If the first component contains the reaction mixture
(A), the content of the antifouling agent (D) is preferred to be
5-600 parts by weight, and is further preferred to be 10-500 parts
by weight, relative to the solid content of 100 parts by weight
of the reaction mixture (A) .
SF-2390 36
[0093] From the viewpoint of possibility of improving the
coating film hardness (strength) while controlling the coating
viscosity rise, the antifouling agent (D) of the antifouling
coating composition of the present invention is preferred to be
5 zinc pyrithione. In this case, the content of the zinc pyrithione
is preferred to be 0. 5-300 parts by weight, and is further
preferred to be 1-200 parts by weight, and is most preferred to
be 10-200 parts by weight relative to the solid content of 100
parts by weight of polyester resin contained in the first
10 component.
[0094] If the first component includes the reaction mixture
(A), it is preferred to be 0. 5-300 parts by weight, and is further
preferred to be 1-200 parts by weight, and is most preferred to
be 10-200 parts by weight relative to the solid content of 100
15 parts by weight of the reaction mixture (A) • From the viewpoint
of improving the coating film hardness (strength), the substances
are preferred in the following order: zinc pyri thione and
2-(p-chlorophenyl)3-cyano-4-bromo-5-trifluoromethyl pyrrole.
From the viewpoint of exhibiting the drying characteristic of the
20 mixture coating, the strength of the coating film formed, and
favorable antifouling property against both animal species such
as barnacles and botanical marine organisms, it is further
preferred to use a zinc pyrithione and a
2-(p-chlorophenyl)3-cyano-4-bromo-5-trifluoromethylpyrrole
SF-2390 37
together.
[0095] <(E) Other additives>
The antifouling coating composition of the present
invention may include at least one of the additives (hereinafter
5 referred to as "additive (E)") selected from the group consisting
of a plasticizer ( el) , extender pigment (e2), pigment
dispersant ( e3) , color pigment ( e4) , dehydrating agent ( e5) ,
anti-sagging agent (e6), and anti-settling agent (e7). The
additive (E) may be contained in the first or second component,
10 or added into a compound having the first and second components
mixed, however, it is preferred to be added into the second
component.
[0096] Below explains the plasticizer ( el) , extender pigment
(e2) (however, excluding zinc oxide), pigment dispersant (e3),
15 color pigment (e4), dehydrating agent (e5), anti-sagging agent
(e6), and anti-settling agent (e7).
[0097] (el) Plasticizer
A plasticizer (el) includes a chlorinated paraffin,
petroleum resins, ketone resins, TCP (tricresyl phosphate),
20 polyvinyl ethyl ether, dialkyl phthalate, (meth) acrylic polymers,
and the like. If the antifouling coating composition of the
present invention includes the plasticizer (el), it is preferable
in that the anti-crack property of the coating film (antifouling
coating) formed from the antifouling coating composition is
SF-2390 38
improved.
[0098] Of these, the plasticizer (e1) is preferred to be a
plasticizer selected from a group consisting of a chlorinated
paraffin, petroleum resins, ketone resins, and (meth) acrylic
5 polymers. These plasticizers can be used in one type, or in
combination with two or more types.
[0099] The content of the plasticizer (e1) is preferred to
be 0.1-300 parts by weight, and is further preferred to be 0.1-200
parts by weight, and is most preferred to be 0.1-150 parts by weight
10 relative to the solid content of 100 parts by weight of polyester
resin contained in the first component.
[0100] If the first component includes the reaction mixture
(A), the content of the plasticizer (e1) is preferred to be 0.1-300
parts by weight, and is further preferred to be 0. 1-2 00 parts by
15 weight, and is most preferred to be 0.1-150 parts by weight
relative to the solid content of 100 parts by weight of the reaction
mixture (A) .
[0101] [Chlorinated paraffin]
The chlorinated paraffin may be linear or branched structure,
20 and may be liquid or solid (fine particle) form at room
temperature.
[0102] The average number of carbons in a chlorinated
paraffin is normally 8-30, and preferably is 10-26. A chlorinated
paraffin having such number of carbons produces an antifouling
SF-2390 39
• coating composition that forms a coating film with fewer cracks
and peelings. If the number of carbons of the chlorinated
paraffin is less than eight, the crack inhibiting effect may be
inadequate, on the other hand, if it is more than 30, the resultant
5 coating film surface may have a deteriorated consumption property
(renewal property) that may lead to a deteriorated antifouling
property.
[0103] The number average molecular weight of a chlorinated
paraffin: is normally to be 200-1,200, and is preferred to be
10 300-1, 100; the viscosity is normally to be 1 or more (poise/25°C),
and is preferred to be 1. 2 or more (poise/25°C); and the specific
gravity is normally to be 1. 05-1. 8 0/25 °C, and is preferred to be
1.10-1. 70/25°C.
[0104] The chlorination rate of a chlorinated paraffin
15 (chlorine content) is normally to be 35-7 5%, and is preferred to
be 35-65%. A chlorinated paraffin having such a chlorination rate
produces an antifouling coating composition that forms a coating
film with fewer cracks and peelings. Commercially available such
chlorinated paraffin includes a "TOYOPARAX 150" and "TOYOPARAX
20 A-70" manufactured by TOSOH CORPORATION. Specifically, as
petroleum resins, C5, C9, styrenic, and dicyclopentadiene -based
resins, and their hydrogenated materials may be used, and their
commercially available products include "Quintone 1500" and
"Quintone 1700" manufactured by ZEON CORPORATION.
5
SF-2390 40
[0105] [ (Meth) acrylic polymer]
A (meth) acrylic polymer contained as a plasticizer (e1)
is preferred to be a (meth) acrylic polymer compatible with a
polyester resin (a3) contained in the reaction mixture (A).
[0106] The (meth) acrylic polymer compatible with the
polyester resin herein represents a (meth) acrylic polymer that
produces a transparent homogeneous solution or a milk-white
homogeneous solution instead of forming a two-liquid solution
layer when mixing the following xylene solutions at a rate of 1: 1
10 at 25 °C as: a xylene solution having a 30 weight % of the polyester
resin; and a xylene solution having a 30 weight % of the polymer
derived from the (meth) acrylic acid.
[0107] By containing the (meth) acrylic polymer compatible
with the polyester resin, the antifouling coating composition
15 produces a coating film excellent in anti-crack property, reduces
seawater consumption rate of the coating film, and maintains the
antifouling property, thus, the durability can be adjusted in a
suitable range. There is also an advantage in that the adhesive
property of the coating film can be further improved if the
20 antifouling coating composition of the present invention is
applied over an existing antifouling coating film.
[0108] Such a (meth) acrylic polymer compatible with a
polyester resin include: a (meth) acrylic ester homopolymer or
copolymer; (meth) acrylic ester homopolymer; at least two types
SF-2390 41
of (meth) acrylic acid ester copolymer; (meth) acrylic
ester· (meth) acrylic acid copolymer; and a (meth) acrylic
ester·styrenic-based copolymer. Such a (meth) acrylic
ester-based polymer may be used in one type, or in combination
5 with two or more types. These (meth) acrylic polymers may be
linear or branched structure, and may have a crosslinking
structure. Specific examples of (meth) acrylic polymer
compatible with polyester resin include, (meth) acrylic acid,
(meth) methyl acrylate, (meth) ethyl acrylate, (meth) butyl
10 acrylate, (meth) isobutyl acrylate, (meth) t-butyl acrylate,
(meth) acrylic acid cyclohexyl, (meth) phenyl acrylate, and a
homopolymer of (meth) acrylic ester such as (meth) acrylic
acid2-acetoacetoxyethyl or a copolymer of these monomers; an
aromatic vinyl compound such as styrene (ST); a copolymer of
15 various monomers such as a vinyl acetate, vinyl chloride, ethylene,
propylene, butadiene, and vinyl ether compound, and a (meth)
acrylic ester-based monomer.
[0109] Further, specific (meth) acrylic polymer compatible
with polyester resin includes the following polymers:
20 (1) a copolymer of a methyl methacrylate (MMA), ethyl acrylate
(EA), and acrylic acid (AA), whose copolymerization ratio
(represented by weight ratio of each component, the same shall
apply hereinafter) as (MMA/EA/AA) is (total in all the components:
100 parts by weight) , and the number average molecular weight is
SF-2390 42
preferred to be 1,000-20,000 and is further preferred to be
1,000-5,000.
(2) a copolymer of a methyl methacrylate (MMA), ethyl acrylate
(EA), and butyl acrylate (BA), whose copolymerization ratio
5 (represented by weight ratio of each component, the same shall
apply hereinafter) as (MMA/EA/BA) is 35-50/20-60/10-50 (total in
all the components: 100 parts by weight ) , and the number average
molecular weight is preferred to be 1, 000-20, 000, and is further
preferred to be 1,000-10,000.
10 (3) a copolymer of a isobutyl methacrylate (i-BMA), t-Butyl
methacrylate (t-BMA), styrene (ST), and stearyl methacrylate
(SLMA), whose copolymerization ratio as (i-BMA/t-BMA/ST/SLMA) is
10-40/10-40/20-60/5-20 (total in all the components: 100 parts by
weight), and the number average molecular weight is 1, 000-100,000
15 and is preferred to be about 1,000-80,000.
(4) a homopolymer of a methyl methacrylate (MMA), whose number
average molecular weight is 1, 000-100,000 and is further preferred
to be about 1,000-20,000.
(5) a homopolymer of an ethyl methacrylate (EMA), whose number
20 average molecular weight is 1, 000-100,000 and is preferred to be
about 1,000-20,000.
( 6) a copolymer of a methyl methacrylate (MMA), and butyl acrylate
(BA), whose copolymerization ratio as (MMA/BA) is 99-50/1-50
(total in all the components: 100 parts by weight), and the number
SF-2390 43
average molecular weight is 1, 000-100,000 and is preferred to be
about 1,000-50,000.
( 7) a copolymer of a ethyl methacrylate (EMA) and butyl acrylate
(BA), whose copolymerization ratio as (EMA/BA) is 100-70/0-30
5 (total in all the components: 100 parts by weight) , and the number
average molecular weight is 1, 000-100,000 and is preferred to be
about 1,000-30,000.
[0110] Among such (meth) acrylic polymers, a hydrophobic
acrylic polymer (e.g., the one whose (meth) acrylic acid ester
10 content exceeds 50 weight % and styrene content is less than 50
weight%) or styrene-based polymer (e.g., the one whose styrene
content is more than 50 weight %) is preferred to be used, and
the (meth) acrylic ester polymer of the above-mentioned ( 1)- (2),
is especially preferred to be used.
15 [0111] The number average molecular weight of such (meth)
acrylic polymer is preferred to be 1,000-20,000 and is further
preferred to be 1,000-10,000, and is especially preferred to be
1, 000-3,000. If the number average molecular weight of the (meth)
acrylic polymer is within the above range, the polishing degree
20 can be effectively adjusted and an antifouling coating film
excellent in stationary antifouling property tend to be formed.
If the number average molecular weight of the (meth) acrylic
polymer exceeds the range shown above, the rise of the coating
viscosity and the reduction effect on the polishing degree of the
•
SF-2390 44
antifouling property are obtained, however, the stationary
antifouling property tends to decrease, and if the molecular
weight of the above (meth) acrylic polymer exceeds the range shown
above, even the antifouling property of the resultant antifouling
5 coating film may be maintained at a high level, the drying
characteristic and the coating film strength may be unacceptable.
[0112] From the viewpoint of preventing the viscosity from
rising, the content of the (meth) acrylic polymer is preferred
to be 0.1-100 parts by weight, and is further preferred to be 0.1-80
10 parts by weight, and is particularly preferred to be 0.1-
50 parts by weight relative to the solid content of 100 parts by
weight of the polyester resin contained in the first component.
[0113] If the first component includes the reaction mixture
(A), the content of the (meth) acrylic polymer is preferred to
15 be 0.1-100 parts by weight, and is further preferred to be 0.1-80
parts by weight, and is particularly preferred to be 0.1-50 parts
by weight relative to the solid content of 100 parts by weight
of the reaction mixture (A) .
[0114] The (meth) acrylic polymer is preferred to be
20 contained in the first component from the viewpoint of storage
stability.
[0115] The average molecular weight (weight average
molecular weight and number average molecular weight) of the
above-mentioned chlorinated paraffin and (meth) acrylic polymer
SF-2390 45
is a value calculated by using a gel permeation chromatography
(GPC) method under the following GPC condition, and a standard
polystyrene calibration curve.
(GPC measurement condition)
5 Device: manufactured by Hitachi L-6200
Column: Hitachi Chemical Gelpack GL-420, GL-430, and GL-440
Eluent: THF
Flow velocity: 2.0ml/min
(e2) Extender pigment
10 An extender pigment (e2) includes (however, zinc oxide is
excluded): talc, silica, mica, clay, potash feldspar, calcium
carbonate also used as anti-settling agent, kaolin, alumina white,
white carbon used as matted medicine, aluminum hydroxide,
magnesium carbonate, barium carbonate, barium sulfate, and the
15 like, and among these, an extender pigment selected from a group
consisting of talc, silica, mica, clay, calcium carbonate, kaolin,
barium sulfate, and potash feldspar is preferred. An extender
pigment is a pigment with a low refractive index, and becomes
transparent wheh mixed with oil or varnish to avoid concealing
20 of the coating surface, and if the antifouling coating composition
of the present invention contains the extender pigment (e2), it
is preferred from the viewpoint of improving the coating film
property such as anti-cracking property.
[0116] The content of the extender pigment ( e2) is preferred
SF-2390 46
to be 0.1-500 parts by weight, and is further preferred to be 50-300
parts by weight, relative to the solid content of 100 parts by
weight of the polyester resin contained in the first component.
[0117] If the first component contains the reaction mixture
5 (A) , the content of the extender pigment ( e2) is preferred to be
0.1-500 parts by weight, and is further preferred to be 50-300
parts by weight, relative to the solid content of 100 parts by
weight of the reaction mixture (A) .
10
15
20
[0118] (e3) Pigment dispersant
Various well-known organic and inorganic pigment
dispersants may be used for the pigment dispersant ( e3) . Organic
pigment dispersant includes an aliphatic amine or organic acids
("Duomeen TDO" manufactured by Lion Co., Ltd. DISPERBYK-101
manufactured by BYK CHEMIE), and the like.
[0119] The content of the pigment dispersant ( e3) is
preferred to be 0. 01-100 parts by weight, and is further preferred
to be 0.01-50 parts by weight, relative to the solid content of
100 parts by weight of the polyester resin contained in the first
component.
[0120] If the first component contains the reaction mixture
(A), the content of the pigment dispersant (e3) is preferred to
be 0. 01-100 parts by weight, and is further preferred to be 0. 01-50
parts by weight, relative to the solid content of 100 parts by
weight of the reaction mixture (A) .
•
SF-2390 47
[0121] (e4) Color pigment
Various well-known organic and inorganic color pigments may
be used for the color pigment ( e4) . An organic pigment includes
a carbon black, naphthol red, and phthalocyanine blue, and the
5 like. An inorganic pigment includes, for example, a blood red,
baryta powder, white titanium pigment, yellow oxide, and the like.
Various coloring agents such as dyes may be included. If the
antifouling coating composition of the present invention includes
a color pigment (e4), it is preferable in that the hue of the
10 antifouling coating film formed from the composition can be freely
adjusted.
[0122] The content of the color pigment (e4) is preferred
to be 0.01-100 parts by weight, and is further preferred to be
0. 01-10 parts by weight, relative to the solid content of 100 parts
15 by weight of the polyester resin contained in the first component.
[0123] If the first component contains the reaction mixture
(A), it is preferred to be 0. 01-100 parts by weight, and is further
preferred to be 0.01-10 parts by weight, relative to the solid
content of 100 parts by weight of the reaction mixture (A) .
20 [0124] (e5) Dehydrating agent
A dehydrating agent (e5) includes an anhydrite gypsum
(CaS04), casting plaster, synthetic zeolite-based absorbent
(product name: Molecular Sieve 3A, 4A, SA, 13X and the like) , and
inorganic dehydrating agent such as ethyl silicate. Of these,
SF-2390 48
the gypsum and the casting plaster are preferred because of high
dehydrating effect. Since a dehydrating agent further improves
the storage stability and the adhesion of antifouling coating
composition, such inorganic dehydrating agent can be used alone
5 or in combination with two or more types.
[0125] The content of the dehydrating agent (e5) is preferred
to be 0.1-100 parts by weight, and is further preferred to be 0.1-50
parts by weight, and is most preferred to be 0.1-20 parts by weight
relative to the solid content of 100 parts by weight of polyester
10 resin contained in the first component.
[0126] If the first component includes the reaction mixture
(A), it is preferred to be 0.1-100 parts by weight, and is further
preferred to be 0.1-50 parts by weight, and is most preferred to
be 0.1-20 parts by weight relative to the solid content of 100
15 parts by weight of the reaction mixture (A) .
[0127] (e6) Anti-sagging agent
An anti-sagging agent (e6) (also called "anti-running
agent") includes an amide wax, hydrogenation castor oil-based
wax, polyamide-based wax, a mixture of both, and synthesized
20 finely-divided silica, and among these, the polyamide-based wax
and synthesized finely-divided silica are preferred. The
commercial available products include: "DISPARLON A630-20XC"
manufactured by KUSUMOTO CHEMICALS, CO., LTD. and "ASAT-250F"
manufactured by ITO OIL CHEMICALS CO., LTD. If the antifouling
SF-2390 49
coating composition of the present invention includes an
anti-sagging agent (e6), it is preferable in that the anti-running
property for coating operation, or the like can be adjusted.
[0128] The content of the anti-sagging agent (e6) is
5 preferred to be 0.1-100 parts by weight, and is further preferred
to be 0.1-50 parts by weight, relative to the solid content of
100 parts by weight of the polyester resin contained in the first
component.
[ 012 9] If the first component contains the reaction mixture
10 (A), it is preferred to be 0.1-100 parts by weight, and is further
preferred to be 0.1-50 parts by weight, relative to the solid
content of 100 parts by weight of the reaction mixture (A) .
[0130] (e7) Anti-settling agent
An anti-settling agent (e7) includes an organoclay Al, Ca,
15 Zn amine salt, polyethylene wax, and oxidation polyethylene-based
wax, or the like, and among these, the oxidation
polyethylene-based wax is preferred. A commercially available
product include: "DISPARLON 4200-20X" manufactured by KUSUMOTO
CHEMICALS, Co., LTD. If the antifouling coating composition of
20 the present invention includes an anti-settling agent (e6), it
is preferable in that the precipitation of solvent insoluble
matters in a storing period can be avoided and the stirring
property can be improved.
[0131] The content of the anti-settling agent (e7) is
5
10
SF-2390 50
preferred to be 0.1-100 parts by weight, and is further preferred
to be 0.1-50 parts by weight, relative to the solid content of
100 parts by weight of the polyester resin contained in the first
component.
[0132] If the first component contains the reaction mixture
(A), it is preferred to be 0.1-100 parts by weight, and is further
preferred to be 0.1-50 parts by weight, relative to the solid
content of 100 parts by weight of the reaction mixture (A) .
[0133] <(F) Organic solvent>
The antifouling coating composition of the present
invention may further include an organic solvent (F), however,
the content corresponding to the volatile organic compound (VOC)
in the organic solvent (F) is limited to 400g or less relative
to 1L of the two-part hydrolysable antifouling coating composition.
15 The volatile organic compound (VOC) preferable herein represents
a material of an organic compound whose boiling point (normal
pressure) is 50-260°C (volatile organic compound (VOC) defined
by WHO) and a material whose boiling point (normal pressure) is
less than 50°C (high volatility organic compound (VVOC) defined
20 by WHO).
[0134] Various well-known solvents with a wide range of
boiling points may be used for an organic sol vent (F) , specifically
including: aliphatic solvent such as turpentine; aromatic
solvents such as toluene and xylene; alcohol solvents such as
•
SF-2390 51
isopropyl alcohol, n-butyl alcohol, and isobutyl alcohol; ester
solvents such as ethyl acetate and butyl acetate; ketone solvents
such as methyl ethyl ketone, methyl isobutyl ketones, and methylic
amyl ketones; and ether or ether ester solvents such as ethylene
5 glycol monomethyl ether, ethylene glycol monobutyl ether,
propylene glycol monomethyl ether, and propylene glycol
monomethyl ether acetate, however, among these, the xylene, methyl
isobutyl ketone, and propylene glycol monomethyl ether are
preferred. These organic solvents can be used in one type, or
10 in combination with two or more types.
[0135] For example, the organic solvents (F) may be contained
in the first component to dilute the reaction mixture (A) . An
organic solvent (G) for diluting the reaction mixture (A) includes,
for example, an aromatic hydrocarbon, aliphatic hydrocarbon,
15 esters, ketones, and alcohols. More specifically, the organic
sol vents include aromatic hydrocarbons such as toluene and xylene,
aliphatic hydrocarbons such as hexane, esters such as ethyl
acetate and butyl acetate, ketones such as methyl ethyl ketone
and methylic isobutyl, and alcohols such as methanol, butanol,
20 and isobutanol. These organic solvents may be used in one type,
or in combination with two or more types. Considering the
relatively high acid value for the solid content of the reaction
mixture (A), and satisfying the both low viscosity and low VOC,
using polar organic solvents such as ester, ketone, and alcohol
SF-2390 52
is more favored than aromatic hydrocarbons, and using ester or
ketone -based organic solvent is further preferred because an
alcohol causes an alcoholysis which may lower the resin viscosity.
[0136] In the antifouling coating composition of the present
5 invention, the content of the volatile organic compound (VOC) is
400g or less relative to 1L of the two-part hydrolysable
antifouling coating composition. By setting the VOC content in
such a range, the environmental load and the influence on human
body can be reduced. This VOC content is a value measured under
10 the condition preferable in the Examples.
15
[0137] [Production method of antifouling coating composition]
An antifouling coating composition of the present invention
can be produced by stirring and mixing a first and a second
components prepared in advance.
[0138] In the preparation of the mixture coating by mixing
and stirring the first and the second components, such known mixing
and stirring devices are used as follows: a high-speed disperser,
and grind mill, basket mill, ball mill, triple roll mill, Ross
mixer, planetary mixer, and versatile Shinagawa agitator.
20 [0139] [Production method of antifouling coating film and
antifouling substrate (antifouling method for substrate)]
An antifouling coating film of the present invention is
obtained by hardening the above-mentioned antifouling coating
composition of the present invention. The production method of
SF-2390 53
the antifouling substrate of the present invention (antifouling
method for substrate) comprises applying or impregnating the
above-mentioned two-part hydrolysable antifouling coating
composition of the present invention onto a substrate (object),
5 and hardening the composition to form an antifouling coating film.
[0140] The substrate to be formed with an antifouling coating
film is not particularly limited, however, it is preferred to be
any of a underwater structure, ship, fishing net, and fishing gear.
For example, if the above-mentioned antifouling coating
10 composition is applied on the surfaces of : underwater structures
such as water supply and drainage outlet for thermal and nuclear
power plants; sludge diffusion prevention films of various oceanic
earthworks for coastal roads, submarine tunnels, harbor
facilities, canals, waterway, etc.; and various formed bodies such
15 as ships and fishery materials (e.g., ropes, fishing nets, fishing
gears, floats, and buoy) for one or more times in accordance with
a common procedure, an antifouling coating film coated ship or
underwater structure can be obtained that is excellent in
antifouling property, capable of releasing the antifouling agent
20 component for a long time, and excellent in anti-cracking property
with appropriate flexibility acceptable even for thickly coating.
[0141] That is, the antifouling coating film to which the
antifouling coating composition of the present invention is
applied and hardened, exhibits excellence in antifouling property
SF-2390 54
in that the adhesion of such aquatic living things as sea lettuce,
barnacle, green laver, serpula, oyster, and bryozoan can be
prevented for a long time continuously. Particularly, even if
the materials of ships are FRP, steel, wood, or aluminum alloy,
5 the antifouling coating film can be appropriately attached to such
surfaces. For example, if the antifouling coating composition
of the present invention is applied on the surface of a underwater
structure, the attachment of marine lives can be prevented, the
function of the structure can be maintained for a long time,
10 obstruction of fishing net can be avoided provided it is applied
on the fishing net, and even more, there is little concern on
environmental pollution.
[0142] The antifouling coating composition of the present
invention may be applied directly on a fishing net, or the ship
15 or underwater structure surface with which a substrate material
such as corrosion control agent and primer is applied in advance.
If a conventional antifouling coating or a coating of the
antifouling coating composition of the present invention is
already applied on the surface of a ship, especially an FRP ship,
20 or an underwater structure, the antifouling coating composition
of the present invention may be over coated for repair. Although
it is not particularly limited, the thickness of the antifouling
coating film formed on the surface of a ship or an underwater
structure is, for example, about 30-250~m/time.
SF-2390 55
[0143] As the above-mentioned antifouling coating film of
the present invention is obtained by hardening the antifouling
coating composition of the present invention, it exhibits a
long-term antifouling property against living things attaching
5 to a wide variety of ships and underwater structures with less
possibility of environmental pollution.
[0144] As above, the present invention provides a two-part
low VOC hydrolysable antifouling coating composition that could
form an antifouling coating film suitable for an ocean vessel
10 having such excellent features as: antifouling property with low
environmental load; evenly consumption property of coating film
in which the coating film consume evenly at a constant rate for
a long time; and long-term antifouling maintainability of coating
films that. maintain the antifouling performance for a long time,
15 and the present invention also provides an antifouling coating
film; and a ship, underwater structure, fishing gear, or fishing
net coated with such antifouling coating film.
Examples
[0145] The present invention will now be explained in greater
20 detail based on examples and comparative examples, with the
understanding that these examples are in no way limitative on the
invention. The "parts" and "%" in the examples and comparative
examples refer to "parts by weight" and "weight %", respectively.
[0146]
SF-2390 56
(Production Example 1: Production of polyester resin solution
(a-1))
In a 2 L four-necked flask, 371.0 parts of isophthalic acid,
427.1 parts of sebacic acid, 238.2 parts of neopentyl glycol and
5 89.0 parts of ethylene glycol were added, and reaction
(esterification reaction) was conducted at 220°C for 5 hours in
the presence of nitrogen gas. During the reaction, the water
generated was removed by reflux dewatering and, measuring the acid
value by KOH titration and the hydroxyl value by the acetylation
10 method, the reaction was suspended when the solid content acid
value reached 100 mgKOH/g and the solid content hydroxyl value
reached 30 mg/KOH. After cooling the reaction mixture, the
mixture was diluted with methyl isobutyl ketone to obtain a
polyester resin solution (a-1) having an acid value of 70 mgKOH/g
15 (100 mgKOH/g in terms of solid content), a hydroxyl value of 21
mgKOH/g (30 mgKOH/g in terms of solid content), a viscosity of
320 mPas, and a heating residue (solid content) of 70.3%. The
resin solution contained a polyester resin (a-1) of 1, 800
weight-average molecular weight. The above-mentioned
20 characteristic values were measured conforming to the "Evaluation
of resin solution characteristics" preferable later.
[0147] (Production example 2: Production of polyester resin
solution (a-2))
Except for changing the amount of the starting materials
SF-2390 57
to that shown in Table 1, a polyester resin solution (a-2)
containing a polyester resin (a-2) was obtained in the same manner
as Example 1, followed by measuring the various characteristic
values.
5 [0148] (Production example 3: Production of polyester resin
solution (a-3))
In a 2 L four-necked flask, 225. 0 parts of isophthalic acid,
366.0 parts of sebacic acid, 205.0 parts of neopentyl glycol, 131.0
parts of ethylene glycol, and 86.0 parts of benzoic acids were
10 added, and reaction (esterification reaction) was conducted at
220 °C for 6 hours in presence of nitrogen gas. The water generated
was removed by reflux dewatering and, measuring the acid value
by KOH titration and the hydroxyl value by the acetylation method,
the reaction was suspended when the solid content acid value
15 reached 43 mgKOH/g and the solid content hydroxyl value reached
115 mgKOH/g. The mixture was then cooled down to 170°C, a
trimellitic anhydride of 108.0 parts was added, the heat in the
mixture was kept for 2 hours, an addition reaction was conducted,
and the reaction was suspended when the solid content acid value
20 reached 90 mgKOH/g and the solid content hydroxyl value reached
60 mgKOH/g. After cooling down. the mi~tu~e was diluted with
methyl isobutyl ketone to obtain a polyester resin solution (a-3)
having an acid value of 63 mgKOH/ g ( 90 mgKOH/ g in terms of solid
content), a hydroxyl value of 42 mgKOH/g (60 mgKOH/g in terms of
SF-2390 58
solid content), a viscosity of 345 mPas, and a heating residue
of 70.0% (solid content). The resin solution contained a
polyester resin (a-3) of 2,060 weight-average molecular weight.
The above-mentioned characteristic values were measured
5 conforming to the "Evaluation of resin solution characteristics"
preferable later.
[0149] (Production Examples 4-7: Production of polyester resin
solutions (a-4)-(a-7))
Except for changing the type and amount of the starting
10 materials to that shown in Table 2, polyester resin solutions
(a-4)-(a-7) containing a polyester resin (a-4)-(a-7) were
obtained in the same manner as Production Example 3, followed by
measuring the various characteristic values.
[0150] (Comparative Production Examples 1-2)
15 As comparative production examples, the usage of starting
materials for the resin solution production was shown in Table
3.
[0151] In Comparative Production Examples 1 and 2, a
synthesize in the same manner as Production Example 3, the solid
20 content acid value was confirmed to be 2 mgKOH/g or less by means
of the KOH titration, and a trimelli tic anhydride was reacted to
obtain polyester resin solutions (a-8) and (a-9) containing
polyester resin (a-8) and (a-9), respectively.
[0152] Also, various characteristic values of the polyester
5
SF-2390 59
resin solutions (a-8)- (a-9) were measured conforming to the
"Evaluation of resin solution characteristics" preferable later.
[0153] [Production example of (meth) acrylic polymer varnish
(a-ll)]
In a reaction container equipped with a stirring machine,
capacitor, thermometer, two units of dripping apparatuses,
nitrogen introduction tube, heating jacket, and cooling jacket,
a xylene of 52. 5 parts and a propylene glycol monomethyl eth~r
of 52. 5 parts were introduced as sol vents, which were stirred while
10 heating up to the reflux temperature (approximately 120°C) under
nitrogen atmosphere.
[0154] Next, in keeping this reflux condition, from one
dripping apparatus, a monomer solution containing 45 parts of
methyl methacrylate, 10 parts of methacrylate, 10 parts of acrylic
15 acid, 35 parts of ethylacrylate, and 1 part by weight of
2,4-diphenyl-4-methyl-1-pentene, and from another dripping
apparatus, 30 parts of t-butylperoxy-2-ethylhexanoate (radical·
polymerization initiator), were simultaneously dripped, to the
above-mentioned solvents for 3 hours, respectively.
20 [0155] After that, while keeping this reflux temperature,
the solvent was further stirred for 1 hour, next, continuing the
stirring, the solvent was added with 0.1 g of
t-butylperoxy-2-hexanoate for 3 times every hour, and then the
solvent was further stirred for 30 minutes. Then, while the
SF-2390 60
temperature was kept on warming up, 66. 9 parts of the sol vent was
collected and the temperature was cooled down to obtain 153. 8 parts
of (meth) acrylic polymer varnish (a-ll) containing a (meth)
acrylic polymer (a-ll). The property of the (meth) acrylic
5 polymer (a-ll) contained in the obtained (meth) acrylic polymer
varnish (a-ll) is shown in Table 4 below.

CLAIMS
1. A two-part hydrolysable antifouling coating composition
free from copper and copper compound which composition comprises
5 two liquids: a first component including a polyester resin whose
a solid content acid value is 50-200 mgKOH/g, a solid content
hydroxyl value is 100 mgKOH/g or less, and a viscosity at 25°C
is 500mPa*s or less; and a second component having a paste form
containing a zinc oxide, wherein the content of a volatile organic
10 compound is 400g/L or less on the basis of the total amount of
the first and the second components.
2. The two-part hydrolysable antifouling coating composition
according to claim 1, wherein the weight average molecular weight
15 of the polyester resin to be measured by a gel permission
chromatography is 5,000 or less.
3. The two-part hydrolysable antifouling coating composition
according to claims 1 or 2, wherein the content of a zinc oxide
20 in the second component is 10-500 parts by weight relative to the
polyester resin (solid content) of 100 parts by weight.
4. The two-part hydrolysable antifouling coating composition
according to any one of claims 1 to 3, further comprising a rosin
SF-2390 86
and/or a rosin derivative.
5. The two-part hydrolysable antifouling coating composition
according to any one of claims 1 to 4, further comprising an
5 antifouling agent.
6. The two-part hydrolysable antifouling coating composition
according to any one of claims 1 to 5, further comprising a zinc
pyrithione as an antifouling agent.
10
7. The two-part hydrolysable antifouling coating composition
according to any one of claims 1 to 6, further comprising at least
one plasticizer selected from a group consisting of a chlorinated
paraffin, petroleum resins, ketone resins, tricresyl phosphate,
15 polyvinyl ethyl ether, dialkyl phthalate, and (meth) acrylic
polymers.
8. The two-part hydrolysable antifouling coating composition
according to any one of claims 1 to 7, further comprising an
20 extender pigment (other than zinc oxide).
9. The two-part hydrolysable antifouling coating composition
according to any one of claims 1 to 8, further comprising a pigment
dispersant.
SF-2390 87
10. The two-part hydrolysable antifouling coating composition
according to any one of claims 1 to 9, further comprising a color
pigment.
5
11. The two-part hydrolysable antifouling coating composition
according to any one of claims 1 to 10, further comprising a
dehydrating agent.
10 12. A two-part hydrolysable antifouling coating composition
comprising two liquids : a first component including a reaction
mixture (A) having a polyester resin (a3) obtained by
polycondensation of an acid component (al) and a polyvalent
alcohol component (a2) ; and a second component having a zinc oxide
15 (B), wherein the acid value and the hydroxyl value of the solid
content in the reaction mixture (A) are 50-200 mgKOH/g and 100
mgKOH/g or less, respectively, a copper and a copper compound are
substantially not included in the two-part hydrolysable
antifouling coating composition, the content of volatile organic
20 compound is 400 g or less with respect to IL of the two-part
hydrolysable antifouling coating composition.
13. An antifouling coating film formed
by hardening the two-part hydrolysable antifouling coating
SF-2390 88
%
composition according to any one of claims 1 to 12.
14. An antifouling method for substrate, comprising applying
or impregnating the two-part hydrolysable antifouling coating
5 composition according to any one of claims 1 to 12, followed by
hardening and forming an antifouling coating film.