The present invention relates to the field of engineered wood products and a method of
5 manufacturing the same. More particularly, the invention relates to wood-based fire
retardant and boiling water proof engineered wood products and a process for
manufacturing wood-based fire retardant and boiling water proof engineered wood
products.
10 BACKGROUND OF THE INVENTION
Description of Related Art
The following discussion of background is intended to present the invention in an
15 appropriate technical context and allow its significance to be properly appreciated.
Manufactured or engineered wood fiber-based products are composite wood
products made by binding wood fibres. They have a variety of commercial and residential
applications owing to their ability to be crafted in accordance with varying but precise
20 design specifications. Over the years, a number of manufactured wood panel products,
such as plywood, particle board, laminated veneer lumber (LVL), Oriented Strand Board
(OSB), Medium Density Fibreboard (MDF) and High-Density Fibreboard (HDF), have
been used to meet the growing demands of the industry. Amongst these, MDF or HDF
wood panels have emerged as being widely popular, owing to a range of advantages such
25 as: being cost-effective, environmentally friendly, having improved durability, increased
strength and ability to be easily machined and decorated per demands of the industry.
3
Conventional MDF or HDF boards are manufactured by breaking down hardwood
or softwood into wood particles or fibres, often in a defibrator, combining the particles
with a wax or resin and a binder, and forming it into panels by applying high temperature
and pressure. MDF or HDF boards are generally cheaper, denser and more uniform than
5 most engineered wood products, for instance, plywood. MDF and HDF boards have
become very popular as wood panels made out of MDF or HDF can be manufactured in
variable sizes (6’x 2’ to 10’x 6’) and thicknesses (1 mm to 45 mm) as per application. In
terms of applications, such MDF and HDF boards having a density of around 500-850
kg/m3
provide many benefits. For instance, they are easily machinable, can be painted or
10 stained, can be used extensively for furniture making, kitchen cabinets, wardrobes,
handicrafts, carved or routed products or a building material. HDF boards, specifically,
are routable with computer numerical control (CNC) router and used in various
applications like furniture, cabinet making, partitions, laminated flooring for interior use,
handicrafts, acoustic usages, packaging, door skins and other varied usages.
15
However, various disadvantages of MDF and HDF boards, such as susceptibility
to very high moisture and temperature, no boiling water resistance, lower rigidity and
lower load bearing capacity limits their use in very widespread applications. Due to such
disadvantages, the use of MDF or HDF boards is limited to mostly indoor applications
20 with moderate climatic conditions. While water-resistant and fire-retardant MDF and
HDF boards are known in the art, there are no products in the known art which comprise
all these properties in a single panel.
[[[
25 There is, thus, a need for better quality single engineered wood panel with
improved properties, preferably of boiling water resistance, high rigidity, and high load
4
bearing strength, dimension stability, high durability and fire resistance, while
maintaining the flexibility and inherent benefits of MDF and HDF boards. There is also
a need for an improved and reproducible process for manufacturing such wooden panels
with superior boiling water proof and fire-retardant properties with high rigidity,
5 dimension stability under humid conditions and load bearing capacity.
The above information disclosed in this section is only for enhancement of
understanding of the background of the invention, and therefore, it may contain
information that does not form the prior art that is already known.
10
SUMMARY OF THE INVENTION
The present disclosure has been made in an effort to resolve the above-described
problems associated with the prior art.
15
Accordingly, the present invention is directed to a panel of improved
manufactured wood products having superior properties.
20
In another preferred embodiment, the present invention is directed to an
engineered panel of improved manufactured wood products having superior properties.
In another preferred embodiment, the present invention is directed to a panel of
25 improved MDF or HDF wood products having superior properties.
In another preferred embodiment, the present invention is directed to a panel of
improved manufactured wood products having superior properties having superior
boiling water proof and fire-retardant properties with high rigidity, dimension stability
30 under humid conditions and load bearing capacity.
5
In another preferred embodiment, the present invention is directed to an
engineered panel of improved manufactured wood products having superior boiling water
proof and fire-retardant properties with high rigidity, dimension stability under humid
5 conditions and load bearing capacity.
In another preferred embodiment, the present invention is directed to a panel of
improved MDF or HDF wood products having superior boiling water proof and fireretardant properties with high rigidity, dimension stability under humid conditions and
10 load bearing capacity.
In another preferred embodiment, the present invention is directed to a
manufacturing process for obtaining a panel of improved manufactured wood products
having superior boiling water proof and fire-retardant properties with high rigidity,
15 dimension stability under humid conditions and load bearing capacity.
In another preferred embodiment, the present invention is directed to a
manufacturing process for obtaining an engineered panel of improved manufactured
wood products having superior boiling water proof and fire-retardant properties with high
20 rigidity, dimension stability under humid conditions and load bearing capacity.
In another preferred embodiment, the present invention is directed to a
manufacturing process for obtaining a panel of improved MDF or HDF wood products
having superior properties.
25
In another preferred embodiment, the present invention is directed to a
manufacturing process for obtaining a panel of improved MDF or HDF wood products
6
with superior boiling water proof and fire-retardant properties with high rigidity,
dimension stability under humid conditions and load bearing capacity.
In another preferred embodiment, the present invention is directed to a panel of
improved manufactured wood products having a density of more than 1000 kg/m3
5 .
In another preferred embodiment, the present invention is directed to an
engineered panel of improved manufactured wood products having a density of more than
1000 kg/m3
.
10
In another preferred embodiment, the present invention is directed to a panel of
improved MDF or HDF wood products having a density of more than 1000 kg/m3
.
15 In another preferred embodiment, the present invention is directed to a panel of
improved manufactured wood products having a density of more than 1000 kg/m3
,
wherein the wood particles are made of hardwood or softwood and are pressed together
with an adhesive.
In another preferred embodiment, the present invention is directed to an
20 engineered panel of improved manufactured wood products having a density of more than
1000 kg/m3
, wherein the wood particles are made of hardwood or softwood and are
pressed together with an adhesive.
In another preferred embodiment, the present invention is directed to a panel of
improved MDF or HDF wood products having a density of more than 1000 kg/m3
25 ,
wherein the wood particles are made of hardwood or softwood and are pressed together
with an adhesive.
7
In another preferred embodiment, the present invention is directed to a suitable
composition of industry excipients such as adhesive, wax, suitable fire-retardant
chemicals, color dye, hardening agents and preservatives.
5 In another preferred embodiment, the present invention is directed to a suitable
composition of industry excipients wherein the adhesive is selected from melamine urea
formaldehyde (MUF) resin with high melamine content, methylene diphenyl diisocyanate
(p-MDI) resin and phenol formaldehyde resin or a combination thereof but not limited to
MUF resin.
10
In another preferred embodiment, the present invention is directed to a suitable
composition of industry excipients wherein the suitable fire-retardant chemicals include
but are not limited to ammonium phosphate, teri-glycyl phosphate, ammonium sulphate,
15 borax, boric acid or a combination thereof.
In another preferred embodiment, the present invention is directed to a suitable
composition of industry excipients wherein the hardening agents include but are not
limited to ammonium sulphate, ammonium chloride, similar salts or their combinations.
20
In another preferred embodiment, the present invention is directed to a
manufacturing process for obtaining a panel of improved manufactured wood products
having a density of more than 1000 kg/m3
, comprising providing wood fibres and a
suitable composition, casting the fibres onto a surface, so as to form a mat; cold pre25 pressing, and hot pressing, wherein the surface on which the fibres are cast is a moving
belt, and wherein the fibres comprise hardwood or soft wood.
8
In another preferred embodiment, the present invention is directed to a
manufacturing process for obtaining an engineered panel of improved manufactured
wood products having a density of more than 1000 kg/m3
, comprising providing wood
fibres and a suitable composition, casting the fibres onto a surface, so as to form a mat;
5 cold pre-pressing, and hot pressing, wherein the surface on which the fibres are cast is a
moving belt, and wherein the fibres comprise hardwood or soft wood.
In another preferred embodiment, the present invention is directed to a
manufacturing process for obtaining a panel of improved MDF or HDF wood products
having a density of more than 1000 kg/m3
10 , comprising providing wood fibres and a
suitable composition, casting the fibres onto a surface, so as to form a mat; cold prepressing, and hot pressing, wherein the surface on which the fibres are cast is a moving
belt, and wherein the fibres comprise hardwood or soft wood.
15 In another preferred embodiment, the present invention is directed to a
manufacturing process for obtaining a panel of improved manufactured wood products
having a density of more than 1000 kg/m3
, comprising use of continuous hot-pressing line
or multi-daylight hot press, for applying high pressure and temperatures and suitable
recipe for press operations for proper curing and pressing.
20
In another preferred embodiment, the present invention is directed to a
manufacturing process for obtaining an engineered panel of improved manufactured
wood products having a density of more than 1000 kg/m3
, comprising use of continuous
hot-pressing line or multi-daylight hot press for applying high pressure and temperatures
25 and suitable recipe for press operations for proper curing and pressing.
9
In another preferred embodiment, the present invention is directed to a
manufacturing process for obtaining a panel of improved MDF or HDF wood products
having a density of more than 1000 kg/m3
, comprising use of continuous hot-pressing line
or multi-daylight hot press for applying high pressure and temperatures and suitable
5 recipe for press operations for proper curing and pressing.
In another preferred embodiment, the present invention is directed to a
manufacturing process for obtaining a panel of improved manufactured wood products
having a density of more than 1000 kg/m3
, comprising proper parameters of pressure and
10 temperature in various zones of continuous press or multi-daylight hot press to get surface
density more than 1200 kg/cubic meter with very good glass type finish, very high impact
resistance and to get a very good quality board.
In another preferred embodiment, the present invention is directed to a
15 manufacturing process for obtaining an engineered panel of improved manufactured
wood products having a density of more than 1000 kg/m3
, comprising proper parameters
of pressure and temperature in various zones of continuous press or multi-daylight hot
press to get surface density more than 1200 kg/m3 with very good glass type finish, very
high impact resistance and to get a very good quality board.
20
In another preferred embodiment, the present invention is directed to a
manufacturing process for obtaining a panel of improved manufactured MDF or HDF
products having a density of more than 1000 kg/m3
, comprising proper parameters of
pressure and temperature in various zones of continuous press or multi-daylight hot press
10
to get surface density more than 1200 kg/m3 with very good glass type finish, very high
impact resistance and to get a very good quality board.
In another preferred embodiment, the present invention is directed to a
5 manufacturing process for obtaining a panel of improved manufactured wood product or
engineered panel of improved manufactured wood product or improved manufactured
MDF of HDF products comprising formulation of a special adhesive for use in the
manufacture of a product with superior boiling water proof and fire-retardant properties
with high rigidity, dimension stability under humid conditions and load bearing capacity.
10
It is to be understood that both the foregoing general description and the following
detailed description of the present invention are exemplary and explanatory and are
intended to provide further explanation of the invention as claimed.
15 BRIEF DESCRIPTION OF DRAWINGS
The above and other objects, features and advantages of the present invention will
now be described in detail with reference to certain exemplary embodiments thereof
20 illustrated in the accompanying drawings which are given herein below by way of
illustration only, and thus, are not limitative of the present invention.
Figure 1 is a pictorial representation of the manufacturing process utilized in the
present invention.
25
Figure 2 is a pictorial representation of the manufacture of the adhesive
component utilized in the present invention.
11
Figure 3 is a graphical representation of the density profile of the product of the
present invention.
Figure 4 is a graphical representation of the water absorption properties of the
5 present invention.
Figure 5 is a graphical representation of the thickness swelling properties of the
present invention.
10 It should be understood that the appended drawings are not necessarily to scale,
presenting a somewhat simplified representation of various features illustrative of the
basic principles of the invention. The specific design features of the present invention as
disclosed herein, including, for example, specific dimensions, orientations, locations, and
shapes will be determined in part by the particular intended application and use
15 environment.
In the figures, reference numbers refer to the same or equivalent parts of the
present invention throughout the several figures of the drawing.
20 DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, reference will now be made in detail to various embodiments of the
present disclosure, examples of which are illustrated in the accompanying drawings and
described below. While the invention will be described in conjunction with exemplary
25 embodiments, it will be understood that present description is not intended to limit the
invention to those exemplary embodiments. On the contrary, the invention is intended to
cover not only the exemplary embodiments, but also various alternatives, modifications,
12
equivalents and other embodiments, which may be included within the spirit and scope
of the invention as defined by the appended claims.
Figure 1 is a pictorial representation of the manufacturing process utilized in the
5 present invention.
Figure 2 is a pictorial representation of the manufacture of the adhesive
component utilized in the present invention.
10 A great variety of wood types can be deployed for manufacturing the panels of
the present invention. The starting materials for the manufacture of the panels of the
present invention may not be different from the type of wood conventionally known in
the art. Preferred type may be Eucalyptus or Poplar. It is conceivable to use combinations
of different wood types as well.
15 The manufacturing process described modifies the conventionally known steps
and parameters of known methods to manufacture wood products, even MDF and HDF
Boards.
As shown in figure 1, the panels of the present invention can be generally made
in a process comprising the following steps:
20
Step 1: Chipping
Solid wood such as eucalyptus wood, or poplar or hardwood or a combination thereof
may be provided to a chipper (1) for primary breakdown into chips. Optionally, the wood
25 may be debarked before breakdown. The resultant chips are checked for chip size which
may be in length of 15 mm to 75 mm and thickness 1.5 mm to 15 mm. The chips are sent
to chip silo for storage and homogenization.
13
Step 2: Screening
The chips from chip silo may be screened on chip screen (2) to control the final chip size
5 (about 1 mm to 5 mm). The oversized chips may be sent for re-chipping and undersized
chips may be used in fuel or other process.
Step 3: Refining
10
The screened chips may be sent via permanent magnets and metal detector to refiner (3)
for fiber generation. In the refiner, chips are first pre-heated with steam at 180ºC to
breakdown the natural resin bond of wood, then the chips are dewatered with pug feed
screw to remove wood moisture and finally defibrated using refiner in which wood chips
15 is ground in an environment of steam between a rotating grinding disc or rotor and a
stationary disc or stator, each with radial grooves that provides the grinding surface to
generate the fiber. The fiber is then pushed into blow line by controlling the blow valve
of refiner.
20 Resin / Adhesive Preparation
As shown in Figure 2, the thermosetting polymer resin or adhesive is prepared separately
outside the main process vessels using 20-40% urea, 10-30% melamine, 40-60%
formaldehyde in a reaction vessel (17). Urea and melamine are added from hoppers (14,
25 15) while formaldehyde is pumped into the reaction vessel (17). The reaction vessel (17)
uses steam for the reaction and creates cross linking polymer with long chains and molar
ratio 1:1.1 to 1:2.5 based on board emission requirement. Preferably, to meet E2 emission
the composition may be in the range of 30-35 % Urea, 20-25% melamine and 47-53%
formaldehyde. Fungicides like sodium pentachlorophenate (SPCP), Chlorothalonil,
30 Carbendazim, Borax, Lindane, Chlorpyrifos (CPS) or silver nano compound about 1% -
14
2% on weight basis may be added in this stage to bring anti-fungal & anti-termite
properties. The adhesive is cooled with cooling water to get desired water tolerance and
gel time. Buffer solution like liquor ammonia or acetic acid (any weak acid) is added to
control the pH. The adhesive prepared is stored in storage tank in the glue kitchen (18) to
5 get final temperature and viscosity before use.
The fiber in the blow line is sprayed upon by adhesive (15% to 30% weight basis) as a
binder, wax 1 % to 2% weight basis) for water resistance and surface smoothness, colour
10 dye (1% to 5% solid basis for identification), water for viscosity, hardener (Ammonium
Chloride or Ammonium sulphate or similar latent hardeners) 1% to 4% based on gel time
of adhesive for faster curing of adhesive. The fire-retardant chemical (Ammonium
phosphate or combination of borax & boric acid or Teri-Glycyl Phosphate or similar fireretardant chemicals in range or their combinations 1% - 5% by weight) are also added in
15 this step.
Step 4: Dryer
The wet fiber sprayed with various chemicals is fed into the tubular flash dryer (4) with
20 entry temperature (from flue gas of energy plant (19) having velocity of 25-35 m/sec) 120
to 180ºC by blow valve of refiner. The flue gas carries the fiber to dryer cyclone for
removal of moist air. The dried fiber is fed to sifter (5, 6) through a rotary air valve (RAV).
Step 6: Sifter
25
The dried fiber having moisture from 7-11 % are sifted to get rid of fibre bundles, glue
lumps, foreign particles etc. After sifter (5, 6) the fibres are conveyed into fibre bin for
storage.
15
Step 7: Forming Station
The fibres are discharged and measured from the fibre bin and transported to the mat
5 former (7) via pneumatic transport system. Then the fibres are formed into a continuous
mat with the former. Moisture of mat is measured by moisture meter and controlled at
dryer stage. The weigh scale gives the feedback to former for feed rate of fiber.
Step 8: Pre-press
10
The mat formed in forming station (7) is conveyed by forming belt on continuous basis
to prepress (8) for de-airing and cold compaction of mat. Ideally mat height after prepress
should be 5 times the final raw board height. The pressure of pre-press should be
controlled accordingly.
15
Step 9: Hot Press
The compressed mat having good moisture (6% to 10%) after scanning through metal
detector is fed into continuous hot press (9). In hot press (9), the mat is compacted to final
20 raw board thickness and glue is cured. The temperatures in first group is maintained 240-
250ºC, 210-220ºC in group 2, 190-210ºC in group 3, 170-180ºC in group 4 and 130-140ºC
in group 5. The pressure is maintained in initial Zone 2-4 from 300 to 450 N/cm2
, Zone
5-8 from 100 to 225 N/cm2
, Zone 9 to 15 from 20-90 N/cm2
, Zone 15-18 from 185 to 200
N/cm2
and Zone 19 around 10-100 N/cm2
based on final thickness. In Zone -1 pressure
is around 50-110 N/cm2
25 . The press factor is 10 to 15 sec/mm for proper curing of board
depending on mat temperature and Glue. The density of raw board is maintained at 970
to 1040 Kg/m3 with thickness control.
16
Alternatively, the compressed mat having good moisture (6% to 10%) is cut and fed into
multi daylight press. In multi daylight press (9), the mat is compacted to final raw board
thickness and glue is cured. The temperature of between 180-190°C is maintained in
platens of the press. The press cycle time for this board is between 300- 400 seconds. The
5 pressure is maintained in initial time T1 (3-6 sec) from 180 to 220 bar, in Time T2 (4-8
Sec) 175 to 200 bar, time T3 (160-200 sec) 150-185 bar and T4 (60-90 sec) 50-75 bar
from T5 (8-15 sec) 50 to 75 Bar, T6 (7-15 sec) from 130 to 160 Bar, T7(10-16 sec) from
100-130 Bar, T8(8-13 sec) from 90 to 110 Bar on final thickness. The press cycle time is
adjusted for proper curing of board depending on mat temperature and Glue. The density
of raw board is maintained at 970 to 1040 Kg/m3
10 with thickness control.
Step 10: Automatic Storage
The pressed raw board is then cut by saw to get master raw boards which after passing
15 through cooling tuner (10) to reduce the board temperature is stored in automatic storage
for 60 to 120 hrs for de-stressing, cooling, complete curing of adhesive and hominization
of board moisture.
Step 11: Sanding
20
The completely cured board is sanded (11) to get uniform final thickness and smooth
surface finish.
Step 12: Cutting
25
The sanded master board is cut (12) to final size to give the final product (13) which can
be used for all application including lamination.
30
17
In commercial, continuous processing, the surface on which the fibres are cast
may generally be a moving belt, with further steps, including the pressing being
conducted via a moving belt, e.g., via a double belt press. However, it is possible to get
the desired results with a multi delight press as well.
5
The present invention, in a broad sense, is based on an appropriate ratio of suitable
amino resin or isocyanides resin with suitable percentage of additives (wax or paraffin,
fire retardant chemicals, hardener, dyes etc.) mixed with wood fiber and produced at very
high density (>1000 Kg/m3
10 ) with suitable temperature and high pressures parameters in
continuous press or multi daylight press. One set of press parameters utilizing continuous
hot-pressing line (press, temperature / distances and coupling factor) including but not
limited to is shown below:
18
The composition as described above may comprise about 70 to 85 % wood, about
18 to 28 % adhesive, about 0.5 to 2.5 % additive, about 4 to 10 % water, about 1 to 3 %
dye, about 1 to 3 % preservative, and 1 to 5 % suitable fire-retardant chemicals. The
5 adhesive can be selected from the conventional adhesives known in the art, such as
phenol-formaldehyde resin, melamine-urea-formaldehyde resin (MUF), or isocyaninebased adhesives among which methylene diphenyl diisocyanate (MDI) and polymeric
methylene diphenyl diisocyanate (pMDI). The adhesive to be used is in range of 18-28%
by weight based on type of adhesive.
10
Additives are used in small amounts, and for different purposes. The most widely
used additive is wax, preferably paraffin, which is added either as a wax melt or in the
form of an aqueous emulsion. Paraffin, or other waxes like slack wax, are mainly added
15 to improve the water absorption and thickness swelling properties of the MDF. Paraffin
Wax is used in a range of about 1 to 3% by weight. Wax emulsion or suspension can also
be used to get similar results. Other additives include colorants (colour dye) which
indicate different grades of MDF or HDF panels. Dye is used in a range of about 1 to 5%
by weight based on type of dye used and colour intensity requirement. Other additives
20 include fungicides or preservatives which are used in a range of about 1 to 3% by weight
including but not limited to Sodium Pentachlorophenate (SPCP), Silver Nano
Compounds, Chlorothalonil, Carbendazim, Borax, Lindane, Chlorpyrifos (CPS). Use of
fire-retardant chemicals including but not limited to Ammonium phosphate or
combination of Borax & Boric acid or Teri-Glycyl Phosphate are done to bring fire
25 retardant properties in panel of invention and is used in a range of about 1 to 6% range
by weight based on the embodiment used.
19
The panels of the present invention have reduced water absorption, reduced
thickness swelling, high surface density, high fire-retardant properties, high impact
resistance, high resistance to fungus and termites, boiling water proof, high load bearing
strength for structural purposes, used such as in stressed skin panels, web beams,
5 sheathing, silos, rail and ship containers and very high screw holding property for
nailability for ease of carpenter for construction of furniture.
As shown in Figure 3, the panels of the present invention can have a density of
above 1000 kg/m3
10 . Particularly, the panels of the present invention can have a high
surface density of about 1200 kg/ m3
thereby rendering the panels with a very high impact
resistance.
The panels of the present invention can further have the following characteristic
15 features which provide for the various advantages listed above:
i. high screw holding – face 4000 N and edges 3000 N;
ii. high Internal bonding strength - above 2 N/mm2
and internal bond after
accelerated water resistance above 0.9 N/mm2
;
20 iii. resistance to boiling water for over 72 hours in accordance with prescribed tests
with no delamination and disintegration of the panels;
iv. very less water absorption i.e., less than 1 % after 2 hours of soaking and less than
4 % after 24 hours of soaking;
v. the linear expansion i.e., swelling in water after 24 hours of soaking, is very low
25 in comparison with the other lignocellulosic fibre board available. Characteristic
features include swelling up to a thickness less than 2%, increase in length and
width less than 0.15 %;
20
vi. average Modulus of Rupture (MOR) is above 50 N/mm2
and average Modulus of
elasticity (MOE) is above 5000N/mm2
;
vii. high modulus of rigidity – tested as prescribed in IS: 1734 – which is above
3500N/mm2
against the minimum requirement of 588N/mm2
;
5 viii. the panels are also fire retardant and tested in accordance with prescribed tests for
12 mm and 18 mm MDF or HDF panels. The panels have very low flammability
and the results are 3 times better than the minimum requirement of the standard;
and,
ix. high compactness due to higher level of pressure given during the production of
10 as a result of which the panels have a high resistance to fungus, termite and borer.
EXAMPLES
The following examples are put forth so as to provide those of ordinary skill in
15 the art with a disclosure and description of how the embodiments claimed herein are
performed. They are intended to purely exemplify the present invention and are not
intended to limit the scope of the disclosure. The other embodiments of the present
invention can be developed using the methods described in the provided examples with
some modifications. The following examples and tests, wherever relevant, have been
20 conducted per the prescribed standards of IS 2380 and related specifications. The panels
or boards tested in the following examples have been produced using the procedure and
parameters as disclosed hereinabove.
Example 1: Moisture Content
25 Test Specimens – The specimens are of the full thickness of the material i.e., 18 mm. 75
mm wide and 150 mm long. Smaller specimens may be used when deemed necessary.
21
When the moisture content of test specimens of any other test is required, the same may
be determined from a coupon cut as near the failure of the specimen, as possible, and may
be of the maximum possible size available from the same. When for any reason additional
determinations of moisture content are required, separate samples may be prepared from
5 the same material as are used in preparing the test specimens. The test may be carried out
immediately after cutting the specimen.
Procedure – Each specimen may be weighed to an accuracy of not less than ± 0.2 percent.
The specimen may be dried in a ventilated oven at a temperature of 103 ± 2°0 until the
mass is constant to ± 0.2 percent between two successive weighing made at an interval of
10 not less than 1 hour.
Calculation and Report – The moisture content, expressed as a percentage of the ovendry mass, is given by the formula:
Moisture Content = M1-Mo / Mo X X100
15
M1 Initial Weight of the Specimen
Mo Final Weight of the Specimen
The results are as follows:
Moisture
Content
Branded
Marine
Plywood
certified as
per IS 710:
2010
Branded
BWP FR
certified
as per
IS5509 &
IS 710
Branded
Structural
ply certified
as per IS
10701: 2012
and Boiling
water Proof
As Per IS
5509
Present
Invention
High
Density and
High
Moisture
Resistant
MDF board
as per IS
12406 Part I
Branded
Medium
density
fiber board
as per IS
12406-part
2
Min (%) 8.25 7.88 8.23 8.65 6.99 7.17
Max (%) 8.33 7.94 8.29 8.69 7.05 7.21
22
Example 2: Thickness
Test Specimens – The test specimen may be about 150 mm long and 75 mm width or any
5 size if deemed necessary. The specimen may be sharp and clear cutting from the whole
panel. The thickness of boards may be measured along the edges of the boards to an
accuracy of ± 0.1 mm, measurements being taken 25 mm from the edge.
Procedure -The contacting surfaces of the measuring instrument may be flat and may have
10 a diameter of at least 6 mm. Care may be been taken so that the surfaces of the board are
not deformed when the thickness is measured.
The results are as follows:
Thickness
Branded
Marine
Plywood
certified
as per
IS 710:
2010
Branded
BWP
FR
certified
as per
IS5509
& IS 710
Branded
Structural
ply certified
as per IS
10701: 2012
and Boiling
water Proof
As Per IS
5509
Present
Invention
Branded
High
Density and
High
Moisture
Resistant
MDF board
as per IS
12406 Part I
Branded
Medium
density
fiber board
as per IS
12406-part
2
Minimum
individual
(mm)
19.05 19.07 18.75 18.01 18.01 17.85
Avg.
(mm) 19.02 19.03 19.20 18.04 18.15 17.99
Req.as
per IS
standard
(mm)
19.00 +/-
5%
19.00+/-
5% 19.00+/- 5% 18.00 +/-
0.3 mm
18.00 +/- 0.3
mm
18.00 +/-
0.3 mm
15
Avg. (%) 8.29 7.91 8.26 8.67 7.02 7.19
Req. (%) 5.00-15.00 Max-20.00 Max-20.00 Max-20.00 5.00-10.00 5.00-10.00
23
Example 3: Density
Test Specimens – The width, length and thickness of each board may be measured in the
manner specified. The mass may be determined to an accuracy of ±0.2 percent. The
5 specimen may be of the full thickness of the material i.e., 18 mm, about 75 mm wide and
150 mm long or any size if deemed necessary.
Procedure – The required test specimen may be cut to the specified size subject to a
tolerance of ±2 mm on the length and width.
10
Calculation and report – The density of each board or test specimen shall be calculated as
per below formula:
Density =
Mass of board or test specimen in g x 10^6
Kg/m³
Length (mm) x Width (mm) x Mean thickness(mm)
The results are as follows:
Density
Branded
Marine
Plywood
certified
as per IS
710: 2010
Branded
BWP FR
certified
as per
IS5509 &
IS 710
Branded
Structural ply
certified as per
IS 10701: 2012
and Boiling
water Proof As
Per IS 5509
Present
Invention
Branded
High
Density
and High
Moisture
Resistant
MDF
board as
per IS
12406 Part
I
Branded
Medium
density
fiber
board as
per IS
12406-
part 2
Min
individual
(Kg/m³)
719 733 753 1037 855 740
Avg. (Kg/m³) 720 735 754 1038 866 755
Req.as per
IS standard
(Kg/m³)
Not
specified
Not
specified Not specified Not
specified 600-900 600-900
15
24
Example 4: Modulus of Rupture
Test Specimens – Test specimen may be 75 mm in width if the nominal thickness is
greater than 6 mm, and 50 mm in width, if the nominal thickness is 6 mm or less. The
length of each specimen has 50 + 24t mm (where t is the nominal thickness of the board
5 in millimeters. The width, Length and thickness of each specimen may be measured to
the accuracy as specified
Procedure –
I) Span and Supports - The span (center-to-center distance between supports) for
each test may be 24 times the nominal thickness. The support may be such that no
10 appreciable crushing of the specimen will occur at these points during the test.
II) The specimen may be loaded at the center of the span with the load applied to the
finished face at uniform rate through a loading block rounded. The bearing blocks shall
be at least 75 mm in width.
Rate of Loading - The load applied continuously throughout the test at a uniform rate of
15 motion of the movable cross head of the testing machine as calculated by the following
formula.
N= Zn²
6t
whereN Rate of motion of moving head in cm/min.
Z Unit rate of fiber strain of outer fiber length per minute = 0.005.
L Span in mm
t Thickness of specimen in mm.
Calculation and Report – The modulus of rupture calculated for each specimen by the
20 following formula, and the values reported. The average values for the length wise
specimens and the breadth wise specimens shall above reported separately:
25
R= 3PL
2bd²
whereR Modulus of rupture in N/mm2
P maximum load in N
L length of span in mm
B Width of specimen in mm
D Depth of specimen in mm
Test has
been
carried out
for random
samples
and result
recorded as
below:
Modulus of
Rapture
Branded
Marine
Plywood
certified
as per IS
710: 2010
Branded
BWP FR
certified
as per
IS5509 &
IS 710
Branded
Structural ply
certified as
per IS 10701:
2012 and
Boiling water
Proof As Per
IS 5509
Present
Invention
Branded
High
Density
and High
Moisture
Resistant
MDF
board as
per IS
12406
Part I
Branded
Medium
density
fiber
board as
per IS
12406-part
2
Min
individual
(N/mm²)
40.21 48.05 55 63.1 55.94 47.96
Avg.
(N/mm²)
42.00 51.45 64 64.61 55.96 47.97
Req.as per
IS
standard
(N/mm²)
Avg 50,
min
individual
45
Avg 50,
min
individual
45
Avg 50, min
individual 45
No
standard
Min 25-
Avg 28
Min
individual
25.00-
Average
28.00
Example 5: Testing procedure for Modulus of elasticity
5
Test Specimens – The test specimen may be 75 mm in width if the nominal thickness is
greater than 6 mm, and 50 mm in width if the nominal thickness is 6 mm or less. The
thickness is the thickness of the material. The length of each specimen has been50 + 24t
10 mm where t is the nominal thickness of the board in millimeters. The width, length and
thickness of each specimen is measured to the accuracy as specified.
26
Calculation and Report – The modulus of elasticity calculated for each specimen by the
following formula and the values reported. The average for the lengthwise specimens and
the breadth wise specimens also be reported separately;
where5
E apparent modulus of elasticity in N/mm2, D26
Y1 central deflection at limit of proportionality load in mm
P maximum load in N
L length of span in mm
B Width of specimen in mm
The results are as follows:
Modulus
of
Elasticity
Branded
Marine
Plywood
certified as
per IS
710: 2010
Branded
BWP FR
certified
as per
IS5509 &
IS 710
Branded
Structural
ply certified
as per IS
10701: 2012
and Boiling
water Proof
As Per IS
5509
Present
Invention
Branded
High
Density
and High
Moisture
Resistant
MDF
board as
per IS
12406
Part I
Branded
Medium
density
fiber
board as
per IS
12406-
part 2
Min
(N/mm²) 3147 4650 5245 5223 4590 3300
Avg.
(N/mm²) 4500 4903 5487 5325 4748 3654
Req.as
per IS
standard
(N/mm²)
Min
individual
6700-
Average
7500
Min
individual
6700-
Average
7500
Min
individual
6700-
Average
7500
No
standard
Min
individual
2500-
Average
2800
Min
individual
2500-
Average
2800
Example 6: Screw withdrawal
10
Test Specimens – The length and width of the test specimen may be 150 mm and 75 mm
respectively. The thickness must not be less than 30 mm. If the thickness of the board is
less than 30 mm, two or more thicknesses of the board may be bonded together with
27
suitable adhesive or clamped. Two wood screws of 8- and 50-mm length may be threaded
into the specimen at right angle to the face up to half of their length in a pre-bore of 2.5
mm. The holes preferably at mid width at about 5mm from the ends of the specimen. If
the screw holding capacity of the edge of the specimen is required the screw may be
5 threaded in a similar way on the edge.
Care must be taken so that sample may not split during driving of the screws in the
specimen. In the nail withdrawal resistance test two nails of 50 mm long and 2.5 mm
shank shall be driven in the specimen in the similar way as screw. But without any pre10 bore a nail has been bright Galvanized. Diamond pointed and has plane heads. Each screw
or nail is used only once
Procedure – The specimen holding fixture shall be attached to the lower platen of the
testing machine. The specimen has been inserted in the fixture with the head of the screw
or nail up. The load applying fixture which is equipped with a slot for easy engagement
15 of the head of the screw or nail shall be attached to the upper platen of the testing machine.
Rate of Loading – Load was applied to the specimen throughout the test by a uniform
motion of the movable head of the testing machine at a rate of 1. 5mm per minute.
Calculation and Report-The maximum load required to withdraw the screw or nail the
20 measure of resistance of the material to direct withdrawal of screw or nail and has been
included in the report.
The results are as follows:
28
Screw
Withdrawal
Face (N)
Branded
Marine
Plywood
certified as
per IS
710: 2010
Branded
BWP FR
certified
as per
IS5509 &
IS 710
Branded
Structural
ply
certified as
per IS
10701:
2012 and
Boiling
water
Proof As
Per IS 5509
Present
Invention
Branded
High
Density
and High
Moisture
Resistant
MDF
board as
per IS
12406
Part I
Branded
Medium
density
fiber
board as
per IS
12406-
part 2
Min (N) 2872 4187 4236 5245 3594 2560
Avg. (N) 2874 4189 4238 5247 3596 2563
Req.as per IS
standard (N)
Not
specified
Not
specified
Not
specified
Not
specified
1500 1500
Screw
Withdrawal
Edge (N)
Branded
Marine
Plywood
certified as
per IS 710:
2010
Branded
BWP FR
certified
as per
IS5509 &
IS 710
Branded
Structural
ply
certified as
per IS
10701:
2012 and
Boiling
water
Proof As
Per IS 5509
Present
Invention
Branded
High
Density
and High
Moisture
Resistant
MDF
board as
per IS
12406
Part I
Branded
Medium
density
fiber
board as
per IS
12406-
part 2
Min
individual
(N)
1985 2650 2850 4400 2680 1845
Result (N) 2142 2879 2912 4543 2849 1985
Req.as pe IS
standard (N)
Not
specified
Not
specified
Not
specified
Not
specified
1250 1250
Example 7: Water Absorption
5 Test Specimens – Each test specimen may be 300 x 300 mm and prepared and conditioned
as specified. All the four edges may be smoothly and squarely trimmed.
Procedure –
29
I) Mass and Volume of Test Specimen - After conditioning, the specimen weighed
to an accuracy of not less than ± 0.2 percent and the width, length and thickness was
measured to an accuracy of not less than ± 0.3 percent. The volume of the specimen was
computed from these measurements.
5
II) Submersion in Water - The specimens were submerged horizontally under 25 mm
fresh clean water maintained at temperature of 27 ± 2. The water being renewed for each
test. The test specimens were separated +by at least 15 mm from each other and from the
bottom and sides of the container. After a 2-hour submersion, the specimens were
10 suspended to drain for 10 minutes, at the end of which time the excess surface water was
removed and the specimen immediately weighed. The specimens were submerged for an
additional period 22 hours and the above weighing procedure repeated.
Calculation and Report – The amount of water absorbed was calculated from the
15 increase in mass of the specimen during the submersion, and the water absorption
expressed as the percentage of mass based on the mass, after conditioning. The specific
gravity of water was been assumed to be 1.00 for this purpose. The density of the
specimen was reported.
20 The results are as follows:
Water
Absorption
Branded
Marine
Plywood
certified
as per
IS 710:
2010
Branded
BWP
FR
certified
as per
IS5509
& IS
710
Branded
Structural
ply
certified
as per IS
10701:
2012 and
Boiling
water
Present
Invention
Branded
High
Density
and
High
Moisture
Resistant
MDF
board as
Branded
Medium
density
fiber
board as
per IS
12406-
part 2 2 hours
30
Proof As
Per IS
5509
per IS
12406
Part I
Result (%) 2.96 4.37 3.75 0.4 2.27 4.72
Req.as per
IS standard
(%)
Not
specified
Not
specified
Not
specified
Not
specified 6 9
Water
Absorption
Branded
Marine
Plywood
certified
as per
IS 710:
2010
Branded
BWP
FR
certified
as per
IS5509
& IS
710
Branded
Structural
ply
certified as
per IS
10701:
2012 and
Boiling
water
Proof As
Per IS
5509
Present
Invention
Branded
High
Density
and High
Moisture
Resistant
MDF
board as
per IS
12406
Part I
Branded
Medium
density
fiber
board as
per IS
12406-
part 2
24 hours
Result (%) 13.08 21.46 7.63 1.6 9.34 15.72
Req.as per
IS standard
(%)
not
specified
not
specified
not
specified
not
specified
13 20
Example 8: Surface Swelling
5 Test Specimens – Test specimens are prepared and conditioned. Each test specimen may
be 125 X 100 mm and of the thickness of the board.
Procedure – The thickness of each test specimen was measured to an accuracy of ±0.03
mm at four places, one in the center of each side and approximately 20 mm from the edge.
10 The points at which the thicknesses arc measured have been clearly and indelibly marked.
The average of the four readings has been recorded. The edges of each test specimen
sealed by quickly dipping them in turn to a depth of 5 mm into a shallow bath of molten
paraffin wax having a melting point of about 55°C, the temperature of the bath being
31
about 90°0. The procedure was repeated until the pick-up of wax for each test specimen
is of the order of 5 g for each 10 mm thickness of the board. Each test specimen was
immersed in fresh clean water having a temperature of 27 ± 2°0, the water being renewed
for each test. The face being tested was immersed to a depth of approximately 3 mm. Care
5 was taken not to wet the top surface of the test specimen. At the end of 2 hours or such
other period as may be specified, each test specimen was withdrawn from water and the
wet surface shall be wiped with a damp cloth. The test specimen was laid, wet face down,
for one hour on a non-absorbent surface, such as a glass sheet. The thickness of each test
specimen was premeasured at the same points as before and to the same degree of
10 accuracy and the increases in thickness has been recorded.
Calculation and Report - The average of the four values of increase in thickness expressed
as percentage of original average thickness was as surface swelling value.
15

The results are as follows:
Surface
Swelling
Branded
Marine
Plywood
certified
as per
IS 710:
2010
Branded
BWP
FR
certified
as per
IS5509
& IS
710
Branded
Structural
ply
certified
as per IS
10701:
2012 and
Boiling
water
Proof As
Per IS
5509
Present
Invention
Branded
High
Density
and
High
Moisture
Resistant
MDF
board as
per IS
12406
Part I
Branded
Medium
density
fiber
board as
per IS
12406-
part 2
Result
(%) 0.53 0.29 0.33 0.35 0.58 1.06
Req.as
pe IS
standard
(%)
not
specified
not
specified
not
specified
not
specified 4 5
32
Example 9: Thickness Swelling
Test Specimens - The test specimens are prepared and conditioned each test specimen
200 X 100 mm and of the thickness of the board.
Procedure – Each test specimen was placed lengthwise in a jig that permits the test
5 specimens to be held against a and at plate to eliminate the effect of any warping that may
have occurred, and that has a dial gauge capable of recording changes in the length of the
specimen to an accuracy of 0·01 mm. The dial reading has been recorded.
The thickness of each test specimen was measured to an accuracy of 0.01 mm at three
10 marked points, one near each end and one in the middle of the length and the mean shall
be recorded. The mass of each test specimen excluding any shims was recorded to an
accuracy of 0·01 g. One of each pair of test specimens was placed in an atmosphere
maintained at 90 ± 5 percent relative humidity at 27 ± 2°0 and the other in an atmosphere
maintained at 40 ± 5 percent relative humidity at 27 ± 2°C. Upon the specimens again
15 reaching nearly constant mass and dimensions, the expansion or contraction, the change
in the mean thickness and the change in mass of each test specimen was recorded. Finally,
the test pieces were dried and re-measured.
Calculation and Report - The average of the three values obtained for the change in
20 thickness expressed as a percentage of the original average thickness was reported as the
swelling value. The increase in length of the measured edge was reported as a percentage
of the nominal length of the test specimen.
The results are as follows:
33
Thickness
Swelling
Branded
Marine
Plywood
certified
as per IS
710: 2010
Branded
BWP FR
certified as
per IS5509
& IS 710
Branded
Structural
ply
certified as
per IS
10701:
2012 and
Boiling
water
Proof As
Per IS 5509
Present
Invention
Branded
High
Density
and High
Moisture
Resistant
MDF
board as
per IS
12406
Part I
Branded
Medium
density
fiber
board as
per IS
12406-
part 2
3.96 7.15 5.42 2.92 5.18 7.41
Req.as pe
IS
standard
not
specified
not
specified
not
specified
not
specified 4 10
Example 10: Dimensional Expansion
Test Specimens - Test specimens are prepared and precisely conditioned until they are
5 substantially constant in mass and dimensions and grouped in pairs. Metal shims may be
cemented to the ends of the test specimens, if desired. Each test specimen shall be 200 X
100 mm and shall be of the thickness of the board.
Procedure – Each test specimen placed lengthwise in a container such as that permits the
10 test specimens to be held against a flat plate to eliminate the effect of any warping that
may have occurred, and that has a dial gauge capable of recording changes in the length
of the specimen to an accuracy of 0·01 mm. The dial reading was recorded. The thickness
of each test specimen was measured to an accuracy of 0.01 mm at three marked points,
one near each end and one in the middle of the length and the mean recorded. The mass
15 of each test specimen excluding any shims was recorded to an accuracy of 0·01 g. One of
each pair of test specimens placed in an atmosphere maintained at 90 ± 5 percent relative
humidity at 27 ± 2°0 and the other in an atmosphere maintained at 40 ± 5 percent relative
humidity at 27 ± 2°C. Upon their again reaching nearly constant mass and dimensions,
34
the expansion or contraction, the change in the mean thickness and the change in mass of
each test specimen was recorded. Finally, the test pieces were dried and re-weighed.
Calculation and Report - The change in length corresponding to each change in condition
5 (i.e., from 65 percent to 40 percent relative humidity or from 65 percent to 90 percent
relative humidity) reported as a percentage of the nominal length. The corresponding
changes in the mass or thickness as percentage of the mass or thickness after conditioning
at 65 percent relative humidity were reported. The equilibrium moisture contents at 40
and 90 percent relative humidity were reported.
10
The results are as follows:
Linear
Expansion
Length
Branded
Marine
Plywood
certified
as per
IS 710:
2010
Branded
BWP
FR
certified
as per
IS5509
& IS
710
Branded
Structural ply
certified as
per IS 10701:
2012 and
Boiling water
Proof As Per
IS 5509
Present
Invention
Branded
High
Density and
High
Moisture
Resistant
MDF board
as per IS
12406 Part
I
Branded
Medium
density
fiber
board as
per IS
12406-
part 2
Result (%) 0.17 0.27 0.37 0.12 0.15 0.31
Req.as pe
IS
standard
(%)
not
specified
not
specified not specified not
specified 0.3 0.4
Example 11: Accelerated Weathering Cyclic Test for Exterior Use
15
Test Specimens - The Sample size taken 50 mm in the square shape in respect to the
relative thickness.
Procedure - Each specimen subjected to six complete cycles of accelerated weathering.
20 Each cycle consisted of the following:
35
a) Immersion in water at 49 ± 2°C for 1 hour.
b) Spraying with steam and water vapor at 93 ± 3°C for 3 hours.
c) Storing at ambient temperatures in a well-ventilated room for 20 hours.
d) Heating in dry air at 99 ± 2°C for 3 hours.
5 e) Spraying again with steam and water vapor at 93 ± 3°C for 3 hours.
f) Heating again in dry air at 99 ±2°C for 18 hours.
After the completion of the six cycles of exposure the material for test was further
conditioned at a temperature of 27 ±2°C and a relative humidity of 65 ± 5 percent for at
10 least 48 hours before being subjected to tests.

The results are as follows:
Internal
Bond (IB)
after
ACCELER
ATED
Water
Resistant
Branded
Marine
Plywood
certified as
per IS 710:
2010
Branded
BWP FR
certified as
per IS5509
& IS 710
Branded
Structural
ply
certified as
per IS
10701:
2012 and
Boiling
water
Proof As
Per IS 5509
Present
Invention
Branded
High
Density
and High
Moisture
Resistant
MDF
board as
per IS
12406
Part I
Brande
d
Mediu
m
density
fiber
board
as per
IS
12406-
part 2
Test result Delaminated 0.3 0.35 1.38 0.11 NA
Req.as pe
IS standard not specified not
specified
not
specified
not
specified 0.3 NA
15
Example 12: Determination of Boiling Water Resistance (BWP) and Boiling Water
Proof (BWP) potential
Test Specimens - From each board at least 4 test pieces each approximately 50 x 50 mm
20 cut from any position in the board.
36
Procedure - For the boiling water immersion tests, these specimens were kept submerged
in a pan of boiling water for a period as specified for the particular grade of the plywood,
for example, 72 hours for BWP and 8 hours for BWR. These test pieces were removed
5 from the water and cooled down to room temperature by plunging them in cold water.
These wet pieces while still in wet condition can also be tested for glue shear strength
and/or adhesion of plies.
The results are as follows:
Internal
Bond
(IB)
after
Boiling
Water
Resistant
BWR
Branded
Marine
Plywood
certified as
per IS
710: 2010
Branded
BWP FR
certified
as per
IS5509 &
IS 710
Branded
Structural
ply
certified as
per IS
10701:
2012 and
Boiling
water
Proof As
Per IS
5509
Present
Invention
Branded
High
Density
and High
Moisture
Resistant
MDF
board as
per IS
12406 Part
I
Branded
Medium
density
fiber
board as
per IS
12406-
part 2
Min
(N/mm²)
Delaminated 0.17 0.21 0.89 NA NA
Max
N/mm²
Delaminated 0.21 0.27 0.93 NA NA
Avg.
N/mm²
Delaminated 0.19 0.24 0.91 NA NA
Req.
N/mm² Min. Pass
standard
Min. Pass
standard
Min. Pass
standard
Not
Specified
Not
Specified
Not
Specified
10
Internal
Bond
after
Boiling
Water
Proof
test
(BWP)
Branded
Marine
Plywood
certified as
per IS
710: 2010
Branded
BWP FR
certified
as per
IS5509 &
IS 710
Branded
Structural
ply certified
as per IS
10701: 2012
and Boiling
water Proof
As Per IS
5509
Present
Invention
Branded
High
Density and
High
Moisture
Resistant
MDF board
as per IS
12406 Part I
Branded
Medium
density
fiber
board as
per IS
12406-
part 2
37
Min
(N/mm²)
Delaminated 0.02 0.13 0.71 NA NA
Max
(N/mm²)
Delaminated 0.06 0.2 0.79 NA NA
Avg.
(N/mm²)
Delaminated 0.04 0.17 0.75 NA NA
Req.
(N/mm²)
Min. Pass
standard Min. Pass
standard
Min. Pass
standard
Not
Specified
Not
Specified
Not
Specified
Example 13: Tensile Strength
Test Specimens - Each test specimen is prepared as prescribed in the standard. The
5 reduced section shall be cut with a hand saw to the size shown. A sharp saw was used to
ensure a smooth surface in the center section. The thickness of the board and the minimum
width of the reduced section has been measured to the accuracy specified. These two
dimensions were used to determine the net cross-sectional area for determining maximum
stress.
10
Procedure –
i. Method of Loading - Self-aligning: Self-tightening grips with serrated gripping
surfaces at least 50 mm in width and at least 50 mm in length has been used to
15 transmit the load from the testing machine to the specimen;
ii. Rate of Loading - The load has been applied continuously throughout the test at a
uniform rate of motion of the movable cross head of the testing machine of 4 mm per
minute. The maximum loads at which the specimens fail has been noted.
20 Calculation and Report - The stress at failure was calculated from the maximum loads for
each specimen and reported. If the failure is within 10 mm of either grip, the test value
shall be discarded. The report shall also include maximum loads for each specimen, the
38
average for the lengthwise specimens and the breadth wise specimens’ separately and the
location and description of the failures.
The results are as follows:
5
Tensile
Strength
Branded
Marine
Plywood
certified
as per IS
710: 2010
Branded
BWP FR
certified
as per
IS5509 &
IS 710
Branded
Structural
ply
certified
as per IS
10701:
2012 and
Boiling
water
Proof As
Per IS
5509
Present
Invention
Branded
High
Density and
High
Moisture
Resistant
MDF board
as per IS
12406 Part I
Branded
Medium
density fiber
board as per
IS 12406-
part 2
Min (N/mm²) 18.9 27.3 31.5 45.30 27.1 22.05
Max (N/mm²) 19.53 28.36 32.82 46.78 27.42 22.44
Avg. (N/mm²) 19.52 28.34 32.80 46.75 27.38 22.41
Req. (N/mm²) Min-42.00 Min-42.00 Min 42.00 Not specified Not specified Not specified
Example 14: Wet bending strength
Test Specimens - The test specimen for Boiling Water Proof panel were rectangular. The
10 depth of the specimen equal to the thickness of material and the width 2.5 cm for depths
less than 6 mm and 5 cm for greater depths. When the grain direction of the face plies is
parallel to the span, the length of the specimen has been 48 times the depth plus 5 cm;
when the grain direction of the face is perpendicular to the span, the length of the
specimen has been 24 times the depth plus 5 cm. The specimen has been preconditioned
15 to a constant mass at a relative humidity of 65 ± 5 percent and at a temperature of 27 ±
39
2°C. The width and depth of each specimen has been measured to an accuracy of not less
than ± 0.3 percent
Procedure - Three test specimen taken as specified from each direction of a sample for
5 cyclic test for 3 cycles, each cycle consisting of 4 h boiling in water and 16 h drying in
an oven at 65 + 2°C or shall be subjected to 72 h of boiling in water. The samples were
kept in water at 27 + 2°C for 1 h and thereafter tested as specified. The duration of boiling
/ drying in oven may be split into shorter intervals by keeping the samples in room
temperature at 27 + 2°C in water (in case of boiling) or in air (in case of drying). The
10 sample shall have an average and minimum individual modulus of elasticity and modulus
of rupture
The results are as follows:
Wet
bending
Strength
MOR
Branded
Marine
Plywood
certified as
per IS
710: 2010
Branded
BWP FR
certified
as per
IS5509 &
IS 710
Branded
Structural ply
certified as
per IS 10701:
2012 and
Boiling water
Proof As Per
IS 5509
Present
Invention
Branded
High Density
and High
Moisture
Resistant
MDF board
as per IS
12406 Part I
Branded
Medium
density
fiber
board as
per IS
12406-part
2
Min
(N/mm²)
Delaminated 25.12 36.14 45.20 Not Tested Not Tested
Avg.
(N/mm²)
Delaminated 25.39 36.69 46.72 Not Tested Not
Tested
Req.
(N/mm²)
Avg 50,
min 45
Avg 50,
min 45
Avg 50, min
45
not
specified
Not Tested Not
Tested
15
Wet
bending
Strength
MOE
Branded
Marine
Plywood
certified as
per IS
710: 2010
Branded
BWP FR
certified
as per
IS5509 &
IS 710
Branded
Structural ply
certified as
per IS 10701:
2012 and
Boiling water
Present
Invention
Branded High
Density and
High Moisture
Resistant
MDF board as
per IS 12406
Part I
Branded
Medium
density
fiber
board as
per IS
40
Example 15: Modulus of Rigidity
Test Specimens - The test specimens were of a square shape with side not less than 25
5 times, and not more than 40 times the thickness. The grain direction of face ply was
parallel to the edge. The thickness (h) and the sides (a) was measured to accuracy up to
0.1 mm. The test specimens were conditioned to a constant mass in a humidity chamber
maintained at a relative humidity of 65 ± 5 percent and at a temperature of 27 ± 2°C. The
mass may be determined to an accuracy of 0.01 g.
10
Procedure - The specimens were in a frame. This frame was supported horizontally on 4
pillars at its corners. The load has been applied vertically at the center on the top of
plywood plate by means of a hemispherical steel ball of diameter 10 times the thickness
of plywood. Load has been applied continuously and uniformly at a rate of 0.003 times
15 the length of the plate expressed in cm/min.
Calculation and Report - The estimate of stiffness has been calculated from the formula
as below and reported for a particular type of the plywood.
Stiffness = Pa2
dh3
20
where P-Maximum Limit
d- Deflection Limit
a- Area
h- Height
Proof As Per
IS 5509
12406-
part 2
Min
(N/mm²)
Delaminated 3377.00 3850.00 3690.00 Not Tested Not Tested
Avg.
(N/mm²)
Delaminated 3381.00 3858.00 3694.00 Not Tested Not
Tested
Req. Min 3400-
Average
3750
Min 3400-
Average
3750
Min 3400-
Average 3750
not
specified
Not Tested Not
Tested
41
The results are as follows:
Modulus of
Rigidity
Branded
Marine
Plywood
certified as
per IS
710: 2010
Branded
BWP FR
certified
as per
IS5509 &
IS 710
Branded
Structural
ply
certified as
per IS
10701:
2012 and
Boiling
water
Proof As
Per IS
5509
Present
Invention
Branded
High
Density
and High
Moisture
Resistant
MDF
board as
per IS
12406 Part
I
Branded
Medium
density
fiber
board as
per IS
12406-
part 2
Min
(N/mm²)
750.00 500.00 750.00 3200.00 Not Tested Not
Tested
Max
(N/mm²)
850.00 524.00 1250.00 3800.00 Not Tested Not
Tested
Avg.
(N/mm²)
800.00 512.00 1000.00 3500.00 Not Tested Not
Tested
Req. as per
BIS-10701
Clause
11.60&11.70
(N/mm²)
Not
specified
Not
specified
588 Not
specified
Not Tested Not
Tested
Example 16: Determination of Flammability
5 Test Specimens - Each test specimen was of the full thickness of the material i.e., 18 mm,
approximately 125 mm wide and 125 mm in length. The specimens were preconditioned
to a constant mass at a relative humidity of 65 ± 5 percent and at a temperature of 27 ±
2°C.
10 Procedure - The test specimens were held vertical 15 mm apart; one specimen being held
40 mm higher than the other. An ordinary Bunsen burner having 3 mm bore is fixed
horizontally so that the flame plays against the lower end of the inner face of the lower
specimen. The axis of the burner is centrally disposed 22 mm above the lower edge of the
lower specimen, the end of the burner being 12 mm away from the face of this specimen.
42
LPG is fed to the burner resulting in a blue flame which when unobstructed is 50 mm
long. The flame ignites the face of the lower specimen which in turn ignites the opposite
face of the higher specimen. The time taken for the higher specimen to be ignited after
the ignition of the lower specimen is recorded. This ignition is usually very distinct and
5 capable of being timed to a few seconds
The results are as follows:
Flammability
Branded
Marine
Plywood
certified as
per IS 710:
2010
Branded
BWP FR
certified as
per IS5509
& IS 710
Branded Structural ply
certified as per IS 10701:
2012 and Boiling water
Proof As Per IS 5509
Present
Invention
Test result
(min) 19.14 22.12 24.26 106
Req.as per IS
5509 (min) Min-30.00 Min-30.00 Min-30.00 Min-30.00
10 Example 17: Determination of flame penetration
Test Specimens - Dimensions and details of the test specimen were same as for the
flammability test
15 Procedure - The test specimen was held horizontally 50 mm above the nozzle of a blowpipe flame. The test specimen was rotated in a horizontal plane at 75 rev/min in such a
way that the center of the flame describes a circle of 25mm diameter. The time taken for
the flame to penetrate the thickness of the plywood is recorded.
20 The results are as follows:
43
Flame
Penetration
Branded
Marine
Plywood
certified as per
IS 710: 2010
Branded
BWP FR
certified as
per IS5509
& IS 710
Branded Structural ply
certified as per IS 10701:
2012 and Boiling water
Proof As Per IS 5509
Present
Invention
Test results
(min) 30 18 47 62
Req.as per
IS 5509
(min)
45.00 minute 45.00 minute 45.00 minute 45.00 minute
Example 18: Determination of rate of burning
Test Specimens - Each test specimen was of the full thickness of the material i.e., 18 mm,
5 approximately 100 in length × 12.5 mm wide. The specimen was preconditioned to a
constant mass at a relative humidity of 65 ± 5 percent and at a temperature of 27 ± 2°C
Procedure - The test specimen is suspended in a fire tube and adjusted at a height of 30
mm from the flame of the burner. The test specimen is ignited by a blue flame and time
10 taken for each 10 percent loss in mass is recorded. The time taken from 30 to 70 percent
loss in mass is taken for the purpose of comparison.
The results are as follows:
Rate of
Burning
Branded
Marine
Plywood
certified as
per IS 710:
2010
Branded
BWP FR
certified as
per IS5509 &
IS 710
Branded
Structural ply
certified as per
IS 10701: 2012
and Boiling
water Proof As
Per IS 5509
Present
Invention
Test result
(min) 3 28 32 39
Req.as per
IS 5509
(min)
Minimum 20
minute
Minimum 20
minute
Minimum 20
minute
Minimum 20
minute
15
44
Example 19: Water Absorption
Test Specimens - Each test specimen is 300 x 300 mm and prepared and conditioned as
specified. All the four edges must be smoothly and squarely trimmed.
5
Procedure –
i. Mass and Volume of Test Specimen - After conditioning, the specimen weighed to an
accuracy of not less than ±0.2 percent and the width, length and thickness may be
10 measured to an accuracy of not less than ±0.3 percent. The volume of the specimen
shall be computed from these measurements.
ii. Submersion in Water -- The specimen submerged horizontally under 25 mm fresh
clean water maintained at temperature of 27 ± 2. The water being renewed for each
15 test. The test specimen may be separated by at least 15 mm from each other and from
the bottom and sides of the container. After a 2-hour submersion, the specimen may
be suspended to drain for 10 minutes, at the end of which time the excess surface water
must be removed and the specimen immediately weighed. The specimen must be
submerged for an additional period 22 hours and the above weighing procedure
20 repeated.
The test was first carried out for 24 hours. Then for further test, the sample from
container was put out every 24 hours up to 120 hrs.
25 Calculation and Report - The amount of water absorbed calculated from the increase in
mass of the specimen during the submersion, and the water absorption expressed as the
percentage of mass based on the mass, after conditioning. The specific gravity of water
may be assumed to be 1000 kg/m3
for this purpose. The density of the specimen also be
reported.
45
The results are as follows:
Water
Absorption
with the
passing
hours.
Branded
Marine
Plywood
certified
as per
IS 710:
2010
Branded
BWP FR
certified
as per
IS5509 &
IS 710
Branded
Structural
ply certified
as per IS
10701: 2012
and Boiling
water Proof
As Per IS
5509
Present
Invention
Branded
High Density
and High
Moisture
Resistant
MDF board
as per IS
12406 Part I
Branded
Medium
density
fiber
board as
per IS
12406-
part 2
24 hrs. (%) 13.08 21.45 7.63 1.6 9.34 14.22
48 hrs. (%) 24.39 23.21 15.42 3.2 14.12 23.47
72 hrs. (%) 30.99 26.24 20.53 4.52 18.61 27.46
96 hrs. (%) 34.98 28.38 22.87 5.87 21.6 32.79
120 hrs.
(%)
38.05 30.17 24.76 6.14 22.16 36.22
Fig. 4 shows the graphical comparison of the results obtained.
5
Example 20: Thickness Swelling
Test Specimens - The test specimens are prepared and conditioned each test specimen
200 X 100 mm and of the thickness of the board.
10
Procedure – Each test specimen was placed lengthwise in a jig that permits the test
specimens to be held against a and at plate to eliminate the effect of any warping that may
have occurred, and that has a dial gauge capable of recording changes in the length of the
specimen to an accuracy of 0.01 mm. The dial reading was recorded. The thickness of
15 each test specimen was measured to an accuracy of 0.01 mm at three marked points, one
near each end and one in the middle of the length and the mean may be recorded. The
mass of each test specimen excluding any shims was recorded to an accuracy of 0·01 g.
One of each pair of test specimens was placed in an atmosphere maintained at 90 ± 5
46
percent relative humidity at 27 ± 2°0 and the other in an atmosphere maintained at 40 ±
5 percent relative humidity at 27 ± 2°C. Upon their again reaching nearly constant mass
and dimensions, the expansion or contraction, the change in the mean thickness and the
change in mass of each test specimen was recorded. Finally, the test pieces were dried
5 and re-measured
The test was first carried out for 24 hours. Then for further test, the sample from container
was put out every 24 hours up to 120 hrs.
Thickness
Swelling
with the
passing
hours.
Branded
Marine
Plywood
certified as per
IS 710: 2010
Branded
BWP FR
certified as
per IS5509 &
IS 710
Branded
Structural ply
certified as per IS
10701: 2012 and
Boiling water
Proof As Per IS
5509
Present
Invention
Branded High
Density and
High Moisture
Resistant MDF
board as per IS
12406 Part I
Branded
Medium
density fiber
board as per
IS 12406-
part 2
24 hrs. 3.96 5.28 4.79 2.92 5.98 14.22
48 hrs. 5.67 6.09 6.10 3.17 8.12 23.47
72 hrs. 7.15 8.04 6.79 3.50 8.98 27.46
96 hrs. 7.98 9.15 7.37 5.50 9.37 32.79
120 hrs. 8.27 10.32 8.52 6.89 22.16 10.34
10 Fig. 5 shows the graphical comparison of the results obtained.
Example 21: Comparison of Physical & Mechanical properties of the panels of the
present invention as compared to marketed wood panels
15 A comparison of the properties of invention with market samples of MDF/HDF boards
various plywood’s in the known art is as follows:
Sl. No. Property Branded
Marine
Plywood
certified as
per IS
710: 2010
Branded
BWP FR
certified as
per IS5509
& IS 710
Branded
Structural
ply certified
as per IS
10701: 2012
and Boiling
water Proof
As Per IS
5509
Present
Invention
Branded High
Density and High
Moisture
Resistant MDF
board as per IS
12406 Part I
Branded
Medium
density fiber
board as per IS
12406-part 2
1 Board Moisture (%) 8.29 7.91 8.26 8.67 7.02 7.19
2 Average Thickness (mm) 19.02 19.03 19 18.04 17.98 17.99
47
3 Average Density (Kg/m3
) 719 735 754 1038 886 749
4 Density Range (Kg/m3
) 690-741 708-789 733-775 1011-1056 874-899 742-754
5 Average MOR (N/mm2
) 40.24 51.45 63.99 64.61 55.96 47.97
6 Average MOE (N/mm2
) 3148 4903 5487 5325 4748 3654
7 Average I.B. (As Per IS12406)
0.29 0.51 0.57 2.91 1.95 0.97
8 Minimum I.B. (N/mm2
) 0.12 0.28 0.31 1.95 1.59 0.79
9 Screw Withdrawal Face
(N)
2874 4189 4238 5247 3596 2563
10 Screw Withdrawal Edge
(N)
2142 2879 2912 4543 2849 1985
11 Water Absorption 2 hrs.
(%)
2.96 4.37 3.75 0.39 2.27 4.72
12 Water Absorption 24
hrs. (%)
13.08 21.45 7.63 1.60 9.34 15.72
13 Surface Swelling 2 hrs.
(%)
0.53 0.29 0.33 0.35 0.58 1.06
14 TS 24 hrs (%) 3.96 7.15 5.42 2.92 5.18 7.41
15 Linear Expansion
Length (%)
0.17 0.27 0.37 0.12 0.15 0.31
16 Linear Expansion Width
(%)
0.21 0.31 0.36 0.11 0.17 0.37
17 Selling Thickness (mm) 19.00 19.00 19.00 18.00 18.00 18.00
18 AWR Test Delaminated Pass Pass Pass Pass Not Tested
19 BWR Test Delaminated Pass Pass Pass Not Tested Not Tested
20 BWP test Delaminated Fail Pass Pass Not Tested Not Tested
21 AWR Internal Bonding
(N/mm2
)
Delaminated 0.30 0.35 1.76 0.11 N/A
22 BWR Internal Bonding
(N/mm2
)
Delaminated 0.19 0.24 0.91 Not Tested N/A
23 BWP Internal Bonding
(N/mm2
)
Delaminated 0.04 0.17 0.75 Not Tested N/A
24 Tensile Strength
(N/mm2
)
19.51 28.34 32.79 >46.75 27.38 22.41
25 Wet Tensile Strength
MOR (N/mm2)
Delaminated 25.39 36.69 39.60 Not Tested N/A
26 Wet Tensile Strength
MOE (N/mm2
)
Delaminated 3381 3858 3694 Not Tested N/A
27 Modulus of rigidity
(N/mm2
)
800 512 1000 3500 Not Tested N/A
As shown in Example 21, the panels of the present invention have remarkable advantages
over the known wooden panels, such as:
5 i. The thickness of the panels is lower but still provides better properties;
48
ii. Density of the panels of the present invention is much higher, thereby
increasing the boiling water resistance and fire-retardant potential of the
panels;
iii. Modulus of rigidity is higher;
5 iv. Screw withdrawal is better;
v. Water absorption and surface swelling is lower; and,
vi. Tensile strength and wet bending strength are higher.
Example 22: Comparison of fire-retardant properties of the panels of the present
invention as compared to marketed wood panels
10
A comparison of the properties of invention with market samples of MDF/HDF boards
various plywood’s in the known art is as follows:
Properties Present
Invention
Branded Structural ply
certified as per IS 10701:
2012 and Boiling water
Proof As Per IS 5509
Branded BWP FR
certified as per
IS5509 & IS 710
Standard Thickness (mm) 18.00 19.00 19.00
Average Thickness (mm) 17.94 18.98 19.04
Average Density (Kg/m3
) 1002 741 684
Density Range (Kg/m3
) 950-1050 730 – 757 663 – 725
Flammability (30 min) 106 24.26 22.12
Flame Penetration (15
min. for every 6mm thick)
62 42 18
Rate of Burning (20 min.) 39 29.50 32
As is evident, the panels of the present invention show superior fire-retardant
15 properties as compared to the panels of the known art.
The present invention has been described with reference to the exemplary
embodiment and the drawings, but the present invention is not limited thereto. The
49
described exemplary embodiment may be changed or modified by those skilled in the art
to which the present invention pertains within the technical spirit of the present invention
and within the scope equivalent to the appended claims.

We Claim:
1. A process for obtaining a panel of improved manufactured wood products, said
process comprising:
debarking solid wood, chipping said solid wood in a chipper and
5 homogenizing said solid wood chips;
screening solid wood chips in a chip screen to a final chip size;
refining screened chips in a refiner for fiber generation wherein the
screened chips are pre-heated with steam, dewatered, defibrated and ground using
a rotating grinding disc and a stationary disc;
10 mixing the fiber with additives such as adhesive, wax, suitable fireretardant chemicals, color dye, hardening agents and preservatives from a glue
kitchen;
drying the wet fiber mixed with additives in a tubular flash dryer;
sifting the dried fiber and storing the sifted fibers in a storage bin;
15 transporting the sifted fibres to a mat former via pneumatic transport
system to form a continuous mat;
conveying the continuous mat to a pre-press for de-airing and cold
compaction;
feeding the compacted mat into a continuous hot press to form a final raw
20 board;
sawing the pressed raw boards to get master raw boards, passing the master
raw boards through a cooling tuner to reduce board temperature and storing the
boards for de-stressing, cooling, curing and homogenization;
sanding the cured boards to a uniform thickness and surface finish;
51
cutting the sanded boards to a final size;
the adhesive is prepared separately outside the main process vessels and
stored in a storage tank before being added to the glue kitchen;
the fire retardant is added to the glue kitchen at the time of mixing the
5 fibers with additives; characterized in that,
the temperature of the hot press is calibrated in Zone 1 to Zone 19 between
130°C to 250°C;
the pressure of the hot press is calibrated in Zone 1 to Zone 19 between 50
to 450 N/cm2
;
10 the sawed boards are stored in the storage tanks for a period of about 60 to
120 hours for hardening and conditioning.
2. The process as claimed in claim 1 wherein the temperature is maintained at 240-
250ºC, 210-220ºC in group 2, 190-210ºC in group 3, 170-180ºC in group 4 and
15 130-140ºC in group 5
3. The process as claimed in claim 1 wherein the pressure in the hot press is
maintained in initial Zone 1 from 50-110 N/cm2
, Zone 2-4 from 300 to 450 N/cm2
,
Zone 5-8 from 100 to 225 N/cm2
, Zone 9 to 15 from 20-90 N/cm2
, Zone 15-18
from 185 to 200 N/cm2
and Zone 19 around 10-100 N/cm2
20 .
4. A process for obtaining a panel of improved manufactured wood products, said
process comprising:
debarking solid wood, chipping said solid wood in a chipper and
25 homogenizing said solid wood chips;
52
screening solid wood chips in a chip screen to a final chip size;
refining screened chips in a refiner for fiber generation wherein the
screened chips are pre-heated with steam, dewatered, defibrated and ground using
a rotating grinding disc and a stationary disc;
5 mixing the fiber with additives such as adhesive, wax, suitable fireretardant chemicals, color dye, hardening agents and preservatives from a glue
kitchen;
drying the wet fiber mixed with additives in a tubular flash dryer;
sifting the dried fiber and storing the sifted fibers in a storage bin;
10 transporting the sifted fibres to a mat former via pneumatic transport
system to form a continuous mat;
conveying the continuous mat to a pre-press for de-airing and cold
compaction;
feeding the compacted mat into a multi daylight press to form a final raw
15 board;
sawing the pressed raw boards to get master raw boards, passing the master
raw boards through a cooling tuner to reduce board temperature and storing the
boards for de-stressing, cooling, curing and homogenization;
sanding the cured boards to a uniform thickness and surface finish;
20 cutting the sanded boards to a final size;
the adhesive is prepared separately outside the main process vessels and
stored in a storage tank before being added to the glue kitchen;
the fire retardant is added to the glue kitchen at the time of mixing the fibers with
additives; characterized in that,
53
in multi daylight press, the mat is compacted to final raw board thickness and glue
is cured;
the temperature of 180-190°C is maintained in platens of the press;
the press cycle time is between 300- 400 seconds;
5 the pressure is maintained between 50 to 200 bar;
the sawed boards are stored in the storage tanks for a period of about 60 to 120
hours for hardening and conditioning.
5. The process as claimed in claim 4 wherein the pressure in the hot press is
10 maintained in initial time T1 (3-6 sec) from 180 to 220 bar, in Time T2 (4-8 Sec)
175 to 200 bar, time T3 (160-200 sec) 150-185 bar and T4 (60-90 sec) 50-75 bar
from T5 (8-15 sec) 50 to 75 Bar, T6 (7-15 sec) from 130 to 160 Bar, T7(10-16
sec) from 100-130 Bar, T8(8-13 sec) from 90 to 110 Bar on final thickness.
15 6. The process as claimed in claim 1 or 4 wherein the sawed boards are stored in the
storage tanks for a period of about 96 hours for hardening and conditioning.
7. The process as claimed in claims 1 or 4 wherein the density of raw board is
maintained 970 to 1040 Kg/m3
in the hot press.
20
8. An improved manufactured wood product board comprising 70 to 85% wood and
with additives such as adhesive, wax, suitable fire-retardant chemicals, color dye,
hardening agents and preservatives which is boiling water resistant and fire
resistant.
25
9. An improved manufactured wood product board as claimed in claim 8 wherein
the adhesive is in the range of 15% to 30% weight basis, wax is in the range of
54
1% to 2% weight basis, colour dye is in the range of 1% to 5% solid basis,
hardening agent may be in the range of 1% to 4%, preservative in the range of
about 1 to 3 %, and fire retardant chemicals can be in the range of 1% - 5% by
weight.
5
10. An improved manufactured wood product board as claimed in claim 9 wherein
the adhesive may be in the range of 18% to 28% and selected from melamine urea
formaldehyde (MUF) resin with high melamine content, methylene diphenyl
diisocyanate (p-MDI) resin and phenol formaldehyde resin or a combination
10 thereof.
11. An improved manufactured wood product board as claimed in claim 10 wherein
the adhesive may be melamine urea formaldehyde (MUF) resin in a composition
of 20-40% urea, 10-30% melamine, 40-60% formaldehyde.
15
12. An improved manufactured wood product board as claimed in claim 11 wherein
the adhesive may be melamine urea formaldehyde (MUF) resin in a composition
of 30-35 % Urea, 20-25% melamine and 47-53% formaldehyde.
20 13. An improved manufactured wood product board as claimed in claim 9 wherein
the fire-retardant chemicals can be selected from a group comprising ammonium
phosphate, teri-glycyl phosphate, ammonium sulphate, borax, boric acid or a
combination thereof.
25 14. An improved manufactured wood product board as claimed in claim 9 wherein
the hardening agent can be ammonium sulphate, ammonium chloride or a
combination thereof.
55
15. An improved wood product board as claimed in claim 9 wherein the preservative
can be a fungicide.
16. An improved wood product board as claimed in claim 15 wherein the fungicide
5 can be selected from a group consisting of sodium pentachlorophenate (SPCP),
pentachloride or Chlorothalonil, Carbendazim, Borax, Lindane, Chlorpyrifos
(CPS) or silver nano compound.
17. An improved manufactured wood product as claimed in claim 8 which has a
10 thickness of 6 mm to 19 mm.
18. An improved manufactured wood product as claimed in claim 8 wherein the board
has a density of above 1000 Kg/m3
.
15 19. An improved manufactured wood product as claimed in claim 8 wherein the board
has a surface density of about 1200 Kg/m3
.
20. An improved manufactured wood product as claimed in claim 8 wherein the board
has a modulus of rigidity of about 3500 N/mm2