TITLE OF THE INVENTION
“AIR SEALING GEL FOR PNEUMATIC TUBELESS TIRES”
APPLICANT
CEAT LIMITED
of RPG HOUSE, 463, Dr. Annie Besant Road,
Worli, Mumbai 400 030, India;
Nationality: India
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner
in which it is to be performed
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FIELD OF THE INVENTION
[0001] The present application relates to an air sealing gel composition for application
inside tire to effectively prevent air loss after tire is punctured on road/off road during
running. In particular, the present invention relates to an air sealing gel composition and a
method of production thereof.
BACKGROUND OF THE INVENTION
[0002] Tires running on road/off road can undergo puncture by nails, screws or spines etc.
which lead to under inflation. Under inflation is a very dangerous situation for tire
performance as well as for the rider. While riding with punctured tire, rider sometimes is
not able to identify loss in air or under inflation and continues to drive with under
inflation. Because of under inflation there is increase in tire wear, tire heating and fuel
consumption by vehicle. It also leads to reduction in resistance to punctures and cuts to
tire, and sometimes under inflation may lead to fatal accidents.
[0003] To overcome these problems, various sealant formulations providing sealing of
puncture in tires have been proposed. US20100331448A1 discloses a tire puncture sealant
comprising rubber latex, and 1,3-propanediol, US20120041099 A1 reports a tire puncture
sealant comprising a rubber latex and/or a resin emulsion, an acetylene alcohol and/or a
derivative thereof. EP0798140 A2 discloses a sealant composition comprising a
particulate, surface-activated, polymeric component dispersed in a fluid medium
comprising water, a freeze preventative selected from alkyl polyols, and latex. The
formulations described in these patent applications manifest some disadvantages such as
the insertion of sealant through valve upon the tire being punctured causes blockage of air
valve because of ground rubber. In sealants containing isoprene rubber latex as a base and
ethylene glycol as an anti-freezing agent, creaming tends to occur in long time storage.
[0004] Sealants having fibrous material may have issues in sealing the puncture if fluid
enters into puncture when unaccompanied by fibrous material. Some tires are
manufactured with a liner and built-in sealant, however are expensive. Built-in TPE
sealants have issues of shrinkage after tire running since the coating of sealant gets
disturbed.
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[0005] US4337322 and US4588758 disclose a further development of tire sealant. These
patents teach the use of asbestos fiber, ethylene glycol and detergent as main components
in the valve-open type sealant. However, the employment of asbestos fiber is carcinogenic
whereas ethylene glycol is toxic to the environment. Hence, inclusion of these components
is not recommended attributed to the wide scale damage that could be caused to the
environment.
[0006] US3981342 and US5295525 report a puncture sealing composition for a tubeless
pneumatic tire comprising a fiber-free blend of a low molecular weight liquid elastomer, a
high molecular weight solid elastomer, and a crosslinking agent.
[0007] A need exists, therefore, for a sealant composition that will eliminate or ameliorate
the difficulties described. Also, the composition as herein described completely fulfills all
requirements concerning efficacy of puncture sealing performance, seal retention
performance, however, without inclusion of any components that are either hazardous to
human or harmful to the environment.
[0008] Accordingly, the objective of the present invention is to provide a sealant
composition which overcomes the drawbacks present in the prior art compositions. The
present inventors have endeavored to develop a sealant composition which is free of a
solvent, fibrous material and/or a crosslinking agent resulting in a composition with
improved ageing, recyclability, easy processability, environment friendly, and economical.
Furthermore, the recyclability and reusability of sealant rubber makes it a completely
green solution with least carbon foot print and economy of operation. The process
employed for its preparation is environmental friendly, cost effective and easily scalable.
SUMMARY OF THE INVENTION
[0009] The object of the present invention is to provide a sealant composition that will
materially alleviate the problems associated with the conventional tire sealant
compositions as discussed above.
[0010] A sealant composition overcoming one or more of the problems identified in the
prior art is provided comprising
(a) a rubber component,
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(b) a tackifier,
(c) carbon black
(d) an oil component, and
(e) a filler.
[0011] Advantageously, the composition of the present invention is free of solvent, fibrous
material and/or crosslinking agent and is devoid of the disadvantages of associated with
their inclusion. In a further embodiment, the sealant composition has excellent puncture
sealing property without affecting the riding and handling experience of vehicle.
[0012] An aspect of the present invention relates to a process for the preparation of a tire
sealant composition comprising three step mixing of components in a two-roll mill,
wherein:
Step a) comprises mixing of the rubber component, and additives,
Step b) comprises blending of the mix obtained in step a) with a filler, carbon black and
processing oil, and
Step c) comprises blending of the mix obtained in step b) with a tackifier.
[0013] Yet another aspect of the present invention comprises pneumatic tubeless tires
comprising the sealant composition of the present invention.
[0014] Other features and advantages of the present invention will become apparent as the
following detailed description proceeds or may be learned by practice of the invention.
The advantages of the invention will be realized and attained by means of the elements
and combinations particularly pointed out in the description. It is to be understood that
both the foregoing general description and the following detailed description are
exemplary and explanatory only and are not restrictive of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0015] For the purposes of the following detailed description, it is to be understood that
the invention may assume various alternative variations and step sequences, except where
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expressly specified to the contrary. Moreover, other than in any operating examples, or
where otherwise indicated, all numbers expressing, for example, quantities of ingredients
used in the specification are to be understood as being modified in all instances by the
term "about". It is noted that, unless otherwise stated, all percentages given in this
specification and appended claims refer to percentages by weight of the total composition
and the recitation of all numerical ranges by endpoints is meant to include the endpoints of
the range, all numbers subsumed within the range and any range within the stated range.
[0016] Thus, before describing the present invention in detail, it is to be understood that
this invention is not limited to particularly exemplified systems or process parameters that
may of course, vary. It is also to be understood that the terminology used herein is for the
purpose of describing particular embodiments of the invention only, and is not intended to
limit the scope of the invention in any manner.
[0017] Unless otherwise defined, all technical and scientific terms used herein have the
same meaning as commonly understood by one of ordinary skill in the art to which this
invention pertains. In the case of conflict, the present document, including definitions will
control.
[0018] It must be noted that, as used in this specification and the appended claims, the
singular forms “a,” “an” and “the” include plural referents unless the content clearly
dictates otherwise. Thus, for example, reference to a “polymer” may include two or more
such polymers.
[0019] The terms “preferred” and “preferably” refer to embodiments of the invention that
may afford certain benefits, under certain circumstances. However, other embodiments
may also be preferred, under the same or other circumstances. Furthermore, the recitation
of one or more preferred embodiments does not imply that other embodiments are not
useful, and is not intended to exclude other embodiments from the scope of the invention.
[0020] As used herein, the terms “comprising” “including,” “having,” “containing,”
“involving,” and the like are to be understood to be open-ended, i.e., to mean including but
not limited to.
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[0021] References herein to “one embodiment”, “one aspect” or “one version” of the
invention include one or more such embodiment, aspect or version, unless the context
clearly dictates otherwise.
[0022] The following definitions are used in connection with the present application
unless the context indicates otherwise. As used herein,
[0023] The term “aging” refers to deterioration of physical and chemical properties by
oxidation over a period of time.
[0024] The term “antioxidant” refers to a chemical used to retard deterioration specifically
caused by oxygen.
[0025] The term “carbon black” refers to a material used in tires that provides strength to
rubber compounds. This material consists essentially of elemental carbon in the form of
near spherical colloidal particles and aggregates. Carbon black is obtained by partial
combustion or thermal decomposition of hydrocarbons.
[0026] The term “filler” refers to a solid compounding material which may be added,
usually in finely divided form, in relatively large proportions, to a polymer.
[0027] The term “Synthetic Rubber” refers to a rubber that is obtained by polymerizing
petrochemical based monomers.
[0028] The term “valve” refers to a device used to admit, retain, check or exhaust air in a
tube or mounted tubeless tire.
[0029] The term “Pneumatic Tire” refers to an air filled tube or tubeless tire. By the term
"Puncture" there is meant any aperture in the tire which results in undesirable air-leakage
from within the tire, such as one caused by puncturing, tire failure or inflation-valve
failure.
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[0030] Further, unless defined otherwise, all technical and scientific terms used herein
have the same meaning as commonly understood by one of ordinary skill in the art to
which the invention pertains.
[0031] In an embodiment, the present invention relates to a tire sealant composition
comprising:
(a) a rubber component,
(b) a tackifier,
(c) carbon black
(d) an oil component, and
(e) a filler.
characterized in that the composition is free of fibrous material and crosslinking agent.
[0032] The major ingredients of the sealant composition of the present invention are the
rubber component, tackifier, carbon black, filler and the oil component. To these major
components are added relatively small amounts of an antioxidant, anti-degrader, and a
flowing agent all of which ingredients or equivalents or substitutes thereof are important to
result in a composition having the properties desired to achieve the objects of the present
invention. Various other additives such as additives for pH adjustment, dispersants,
thickening agents, anti-ozonents, anti-static materials, adhesion promoters such as
resorcinol formaldehyde resin, additives to prevent wire corrosion may be added to the
composition of the present invention to alter the properties based on the requirement.
[0033] The rubber component which can be used for the purposes of the present invention
may be synthetic rubbers selected from polybutylene, isobutylene, low molecular weight
polyisoprene, polybutylene-isoprene rubber, a styrene-butadiene copolymer rubber, a
butadiene rubber and a styrene-isoprene copolymer rubber or their mixtures. Suitably, the
percentage of the rubber component may range from 1 to 60 percent, or from 1 to 50
percent by weight to the total weight of the sealant composition. Most preferably, sealant
composition will generally include from about 5 to 40 percent by weight of the rubber
component.
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[0034] In an embodiment, the rubber component is a blend of low molecular weight
polyisoprene, or polybutylene, and an isobutylene based polymeric gel in a ratio of about
1:1 to about 2:1.
[0035] Tackifier is required to provide some "tack" characteristic to the compositions of
the present invention. Tackifiers aid in improving the effective preparation by increasing
the stickiness of the surface to provide the composition with high initial adhesivity and
softness. Suitable tackifiers which can be used for the purposes of the present invention
include, but are not limited to terpene resins, petroleum resins, hydrogenated rosins, rosin
glycerides, rosin emulsion, hydrogenated rosin glycerides, rosin pentaerythritol aliphatic,
terpene phenol resin, a hydrogenated petroleum resin or a mixture of two or more. In a
preferred embodiment, the tackifier is selected from terpin resin, phenol resin, rosin resin,
petroleum resin, or phenol formaldehyde resin. Suitably, 1 to 10 percent by weight of a
tackifier corresponding to the total weight of the sealant composition may be present.
[0036] The composition of the present invention contains from 5 to 20 percentage by
weight of carbon black to the total weight of the sealant composition. Exemplary forms of
carbon black preferred in the context of the present invention include Acetylene black,
Thermal black, Furnace black or their combinations thereof. Especially preferred is the
kind of carbon black known as Furnace black (grades described in ASTM D 1765
employed either individually or in combination with different grades this component).
[0037] In order to stabilize shaping, processing oil such as naphthenic oil or aromatic oil ,
or their mixtures may be employed in the composition. Various other oils which are
compatible with the rubber component may be used. Representative of such oils are
paraffinic, naphthenic, aromatic, pine tar and synthetic oils. In a preferred embodiment,
the processing oil is naphthenic oil. Typical amount of oil which may be used for the
purposes of the present invention may be in the range of 1 to 30 percentage by weight to
the total weight of the sealant composition.
[0038] Suitable fillers which may be used for the purposes of the present invention may
be selected from the group consisting of sand, barite, sodium carbonate, sodium meta
silicate, zinc stearate, calcium carbonate, ground marble, iron oxide, manganese oxide,
glass bead, crushed vulcanized rubber, crushed glass, crushed drill cutting, ground vehicle
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tire, crushed rock, ground asphalt, crushed concrete, crushed cement, salt, ilmenite,
hematite, silica flour, fume (amorphous) silica, spherical cured rubber beads, fly ash, an
elastomer, a polymer, or diatomaceous earth. The amount of a filler to be used in the
present invention is in the range of from 5 to 45 percentage by weight, or preferably from
about 16 to 24 percentage by weight to the total weight of the sealant composition. In a
specific embodiment, the filler is a combination of carbon black, sodium carbonate,
sodium Meta silicate or zinc stearate, and spherical cured rubber beads.
[0039] Suitable antioxidants which may be used for the purposes of the present invention
include amine based antioxidants selected from the group consisting of N-phenyl-1-
naphthylamine, alkylated diphenylamine, octylated diphenylamine, 4,4'-bis(,-
dimethylbenzyl)diphenylamine, p-(p-toluenesulfonylamido)diphenylamine, N,N'-di-2-
naphthyl-p-phenylenediamine, N,N'-diphenyl-p-phenylenediamine, N-phenyl-N'-
isopropyl-p-phenylenediamine, N-phenyl-N'-(1,3-dimethylbutyl)-p-phenylenediamine,Nphenyl-
N'-(3-methacryloyloxy-2-hydroxy propyl)-p-phenylenediamine, N-phenyl-N'-(1,3-
dimethylbutyl)-p-phenylenediamine and other aromatic amine compounds.
[0040] Preferably the antioxidant is present in the composition in an amount of at least
0.01% by weight, more preferably at least about 0.1% by weight, even more preferably
from about 2% by weight. However, the amounts of antioxidant used can be varied within
wide limits in accordance with the intended use of the composition. In some sealant
applications the sealant composition of the present invention can be used free of the
antioxidant.
[0041] Suitable anti-degrading agents which can be used for the purposes of the present
invention include, but are not limited to 2,2,4-Trimethyl-1,2-Dihydroquinoline polymer,
acetone/diphenylamine condensate, dicyclohexylamine and a nitroso aromatic amine or
their combinations thereof.
[0042] Suitable flowing agents which may be used for the purposes of the present
invention include, but are not limited to alkaline earth metal salts such as the carbonate
salts and preferably one or more compounds selected from the group consisting of sodium
carbonate, magnesium carbonate, calcium carbonate, or zinc carbonate. The amount of a
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flowing agent may be in the range of from 0.5 to 3 percentage by weight to the total
weight of the sealant composition.
[0043] In accordance to an advantageous embodiment, the sealant composition of the
present invention is free of organic solvents which impart adverse effects to tires. Solvents
& solvent vapors when present in sealant composition interact with the inner liner & bead
areas of tire and degrade the fabric and rubber compounds used in those areas resulting in
damages /loss of strength on inner-liner /bead areas. Also these solvents & solvent vapors
are hazardous to human health since they are inflammable and hence negatively affect
safety at work place. Non usage of these organic solvents leads to improvement in tire life,
safer processing and handling, and a more environmental friendly composition.
[0044] The various components of the sealant composition of the present invention are
believed to be easier to handle and more environmentally safe than many of the
ingredients used in making the sealants of the prior art. Advantages achieved by nonemployment
of cross linking agent and fibrous material are improvement in aging property
(more shelf life), stable performance over a time period, easy to remove from tire and
recyclable & easy to process.
[0045] Recyclability and reusability of sealant rubber makes it a completely Green
solution with least carbon foot print and economy of operation. The sealant composition of
the present invention has excellent puncture sealing properties without affecting riding and
handling experience of vehicle.
[0046] Another aspect of the present invention relates to a process for the preparation of a
tire sealant composition comprising a three step mixing of components in a two-roll mill,
wherein:
Step a) comprises mixing of the rubber component and additives,
Step b) comprises blending of the mix obtained in Step a) with the filler, carbon black and
processing oil, and
Step c) comprises blending of the mix obtained in Step b) with a tackifier.
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[0047] Suitably, the components are mixed for about 5 to 30 minutes, or from 5 to 10
minutes at each stage. The mix obtained from Step a) and Step c) are suitably taken out in
the form of a sheet/dough.
[0048] The method for applying or injecting the air sealant gel composition of the present
invention into the tire is not particularly limited and a conventionally known method can
be used. It is highly preferred however that the semi-solid but highly tacky sealant material
of the present invention be applied like a squeegee. Non-limiting preferred application
methods also include extruding/spraying/application in green tire as a sandwich between
IL and body ply.
[0049] The sealant composition of the present invention is very safe in terms of bike
riding, handling & breaking after applying sealant with excellent puncture sealing and
aging properties. After running 3,000 kilometers with two puncture in tire, air loss in
sealant applied tire is 3-4 Psi which is similar to loss in normal tire.
[0050] In order to illustrate the invention more clearly, the following examples are given
explaining the preferred modes of carrying it into effect and the advantageous results
obtained thereby. The use of examples in no way limits the scope and meaning of the
invention or of any exemplified term. Likewise, the invention is not limited to various
embodiments given in this specification.
EXAMPLES
[0051] The following examples are set forth to further exemplify the invention and are not
intended to be limiting thereof.
EXAMPLE 1:
[0052] A preferred sealant composition according to the instant invention was prepared
having the following composition.
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The Formulation is as follows:
TABLE 1
Representative formulations of TABLE 1
TABLE 2: 1 Kg of air sealing gel for pneumatic tubeless tires consist of following
composition.
Ingredient Components
Isobutylene based polymeric gel (Primary
Blocking agent)
10-50%
Rubber component 5-40%
Antioxidant/Antifatgue agent 0.1-2%
Tackifier 1-10%
Filler 5-40%
Rubber process oil 0-30%
Flowing agent 0.5-3%
Ingredient Components
( grams)
Isobutylene based polymeric gel (Primary
Blocking agent)
205.9
Rubber component 382.4
Antioxidant/Antifatgue agent 11.8
Tackifier 58.8
Filler 147.1
Rubber process oil 176.5
Flowing agent 17.6
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TABLE 3: 1 Kg of air sealing gel for pneumatic tubeless tires consist of following
composition.
Preparation of the sealant composition:
[0053] The sealant composition was prepared in a two-roll mill which is a machinery
traditionally used for mixing rubber compounds. The invention employs a three step
mixing in two roll mill wherein in the first stage master batch mixing of the rubber
component (a combination of isobutylene based polymeric gel and Low molecular weight
polyisoprene/polybutylene), flowing agent (Calcium carbonate or magnesium carbonate or
sodium salt of carbonate), antioxidant(N-phenyl-N'-(1,3-dimethylbutyl)-pphenylenediamine),
and antidegrader(2,2,4-Trimethyl-1,2-Dihydroquinoline polymer)
takes place in the roll-mill for about 5 minutes. The product obtained is taken out as a
sheet. Then filler (Combination of carbon black, Sodium carbonate, sodium Meta silicate,
or zinc stearate, Spherical cured rubber beads) and processing oil are added to the sheet
and allowed to mix for about 10 minutes. Finally, the tackifier, Phenol formaldehyde resin
and natural rosins is added and mixed in the roll-mill for about 10 minutes. The sealant
composition is taken out in sheet form from the roll-mill.
Ingredient Components
( grams)
Isobutylene based polymeric gel (Primary
Blocking agent)
235.3
Rubber component 352.9
Antioxidant/Antifatgue agent 11.8
Tackifier 58.8
Filler 117.6
Rubber process oil 205.9
Flowing agent 17.6
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Comparative Example:
[0054] The physical properties and performance of the sealant composition of the present
invention was compared with the sealant compositions available in the market. The results
are tabulated below.
Type of
Sealant
Liquid type
Comparative
Sample 1
Gel type
Comparative
Sample 2
TPE polymer
base sealant
Comparative
sample 3
Sealant
composition of the
present invention
Formulation
&
Functionality
Spherical cured
rubber beads
1.5% -Filler
Spherical
cured rubber
beads
1.5% -
Blocking
agent
Polyisobutylen
e rubber
100 PHR -
Blocking agent
Isobutylene based
polymeric gel
10-50% - Blocking
agent & Reinforcing
agent
Polymer latex
30% - Carrier,
Sealant
Polymer latex
30% - Carrier,
Blocking
agent
SIS Block
copolymer
40 PHR -
Adhesive,
tackifier,
Low molecular
weight
polyisoprene/polybu
tylene- Tackifier,
viscocity modifier
Phenolic resin
30%-
Thickening
agent &
adhesive,
bonding
strength
increase
Phenolic
resin
30%-
Thickening
agent &
adhesive,
bonding
strength
increase
Process oil
30 PHR- For
processing
easily &
increase
elasticity
Process oil
0-30% - For
processing easily &
increase elasticity
Polyvinyl
acetate
20% -
Thickening
agent &
adhesive,
bonding
strength
increase
Polyvinyl
acetate
20% -
Thickening
agent &
adhesive,
bonding
strength
increase
Reinforcing
Resin
5 PHR -
Reinforcement
material
Tackifier (phenol
formaldehyde resin
)
Alkenes glycol
10% -
Antifrezing
agent,
Surfactant for
resin
Alkenes
glycol
10% -
Antifrezing
agent,
Surfactant for
resin
Calcium
stearate
2 PHR -
Wetting agent,
improve
flowing
property.
Filler (Combination
of carbon black,
Sodium carbonate,
sodium Meta
silicate, or zinc
stearate, Spherical
cured rubber beads)
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1.5% -
Surfactant
1.5% -
Surfactant
Amine based
antioxidant
0.4 PHR -
Antioxidant ,
Stabilizer
Amine based
Antioxidant & Anti
degrader. ( (Nphenyl-
N'-(1,3-
dimethylbutyl)-pphenylenediamine),
and 2,2,4-
Trimethyl-1,2-
Dihydroquinoline
polymer)
Organic
solvent :
Solvent for
dissolving PVA
& Resin
Water:
3% (Prepare
Dispersol F
solution)
Calcium carbonate
or magnesium
carbonate or sodium
salt of carbonate
- Flowing agent -
Water :
5% - Viscocity
modifier
Application
method
Through valve
core injection
method
Through
valve core
injection
method
Spraying
Technique
Extruding /
Spraying/Applicatio
n in green tire as a
sandwich between
IL and body ply
OBSERVATIONS
Physical
Observation
Sealing
property is
good but
material is
drying if tire is
kept open in
atmosphere,
Short shelf life
and unsafe for
processing and
handling.
Sealing
property is
good but
material is
drying if tire
is kept open
in
atmosphere,
Short shelf
life and
unsafe for
processing
and handling.
Green strength
is very low
and not able to
seal puncture
Good shelf life, easy
to recycle, safe for
processing and
handling &excellent
sealing property.
Punture
sealing
performance
A* A* B* A*
Seal retention
performance
B# B# B# A*
Air loss after
punctured
with nail
No air loss No air loss Not able to
seal
No air loss
Air loss after
running 3,000
kilometer
12 Psi 14 Psi Not able to
seal
3 PsI
Storability C+ C+ B+ A+
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* Puncture sealing performance results were expressed on two point scale A (Sealing) &
B (Not sealing)
# Seal retention performance results were expressed on two point scale A (No air leckage
occured) & B (Air leckage occured)
+ After preparing sealant composition was allowed to stand for 10 days at a temperature of
70 °C., change in state of puncture was visually evaluated. the results were expressed on a
three point scale of A (No change, gel form), B(Minor change), C (Unstable)
[0055] A person skilled in the art will be able to practice the present invention in view of
the description presented in this document, which is to be taken as a whole. Although the
foregoing invention has been described in some detail by way of illustration and example
for purposes of clarity of understanding, one of skill in the art will appreciate that certain
changes and modifications may be practiced within the scope of the appended claims.
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We Claim:
1. A tire sealant composition comprising:
(a) a rubber component,
(b) a tackifier,
(c) carbon black
(d) a processing oil, and
(e) a filler.
characterized in that, the composition is devoid of fibrous material and crosslinking agent.
2. The composition as claimed in claim 1, wherein the rubber component is selected from
polybutylene, isobutylene, low molecular weight polyisoprene, polybutylene, isoprene
rubber, a styrene-butadiene copolymer rubber, a butadiene rubber and a styrene-isoprene,
copolymer rubber or their mixtures.
3. The composition as claimed in claim 1, wherein the rubber component is a blend of low
molecular weight polyisoprene, or polybutylene, and an isobutylene based polymeric gel.
4. The composition as claimed in claim 1, wherein the tackifier is selected from terpin
resin, phenol resin, rosin resin, petroleum resin, or phenol formaldehyde resin.
5. The composition as claimed in claim 1, wherein the content of carbon black ranges
between 5 to 15 percentage by weight to the total weight of the sealant composition.
6. The composition as claimed in claim 1, wherein the processing oil is selected from
naphthenic oil.
7. The composition as claimed in claim 1, wherein the content of processing oil may range
from 1 to 30 percentage by weight oil to the total weight of the sealant composition.
8. The composition as claimed in claim 1, wherein the filler may be selected from sodium
carbonate, sodium metal silicate, zinc stearate or crushed vulcanized rubber.
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9. The composition as claimed in claim 1, wherein the amount of filler in the composition
may range from 5 to 45 percentage by weight to the total weight of the sealant
composition.
10. The composition as claimed in claim 1, wherein the filler is a combination of carbon
black, Sodium carbonate, sodium Meta silicate or zinc stearate, and spherical cured rubber
beads.
11. The composition as claimed in claim 1, wherein it comprises an antioxidant.
12. The composition as claimed in claim 11, wherein the antioxidant is an amine based
antioxidant selected from N-phenyl-1-naphthylamine, alkylated diphenylamine, octylated
diphenylamine,4,4'-bis(,-dimethylbenzyl)diphenylamine,p-(p-toluene sulfonylamido)
diphenylamine,N,N'-di-2-naphthyl-p-phenylenediamine,N,N'-diphenyl-p-phenylene
diamine , N-phenyl-N'-isopropyl-p-phenylenediamine, N-phenyl-N'-(1,3-dimethylbutyl)-
p-phenylenediamine,N-phenyl-N'-(3-methacryloyloxy-2-hydroxypropyl)-p-phenylene
diamine, N-phenyl-N'-(1,3-dimethylbutyl)-p-phenylenediamine and other aromatic amine
compounds.
13. The composition as claimed in claim 1, wherein it comprises an anti-degrader.
14. The composition as claimed in claim 13, wherein the anti-degrader is 2,2,4-Trimethyl-
1,2-Dihydroquinoline polymer.
15. The composition as claimed in claim 1, wherein it comprises a flowing agent.
16. The composition as claimed in claim 15, wherein the flowing agent is selected from
the group consisting of sodium carbonate, magnesium carbonate, calcium carbonate, or
zinc carbonate.
17. The composition as claimed in claim 1, wherein the composition is free of an organic
solvent.
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18. A process for the preparation of a tire sealant composition comprising a three step
mixing of components in a two-roll mill, wherein:
Step a) comprises mixing of the rubber component, and other optional additives,
Step b) comprises blending of the mix obtained in Step a) with the filler, carbon black and
processing oil, and
Step c) comprises blending of the mix obtained in Step b) with a tackifier.
19. The process as claimed in claim 17, wherein the optional additives comprise a flowing
agent, antioxidant, and an anti-degrader.
20. Pneumatic tubeless tire comprising the sealant composition as claimed in claim 1.