Title of Invention

JUTE COMPOSITE IN THE FORM OF SHEET & FABRIC FOR MANUFACTURE OF FOOTWEAR COMPONENT

Abstract A Jute Composite in the form of sheet, fabric for manufacture of footwear components like toe puff, Counter stiffener and Insoles, said composite comprising jute fibre / fabric with natural or synthetic fibres / fabrics, said fibres / fabrics being impregnated with emulsion and / or coated with adhesive, wherein the adhesive used for toe puff and counters has the following formulations: Polystyrene : 25 to 40% by wt. Waste / Jute caddies : 10 to 25% by wt. Plasticizer : 0.5 to 3% by wt, Fillers : 5 to 25% by wt, Solvent : Balance Wherein the emulsion is prepared by combing styrene monomer, talc, PVA and SBR,
Full Text The present invention relates to jute composites in the form of sheets, fabrics and
like for use as footwear components and method of manufacture of such
composites. In particular, the jute composites of the invention are used for the
manufacture of various footwear components such as toe puff sheets, counter
stiffener sheets, insoles sheet and cut and skived components. The footwear
components produced from the jute composites according to the invention have
superior application properties.
It is well known to provide toe puff in toe (front) portion of a footwear while counter
stiffener is used on the backside of a footwear. Both are inserted between the
leather and lining material for the purpose of stiffness, shape retention etc. Insoles
are important components are used while pasting and stitching with the upper and
is inside the outer sole. All these components or semi-finished sheet materials are
commonly produced from leather, leather board, man-made synthetic non-woven,
cotton woven fabrics, cellulose paper pulp etc.
Such cotton and leather based materials are expensive and add to the footwear
cost. Also such cotton/leather based materials are not readily available and involve
complex manufacturing process. Such materials are required to be imported in the
form of large volumes of semi finished sheet materials for toe puff, counters and
insoles. These sheet materials are cut to shape either by the fabricators doing job
work or by the footwear manufacturers themselves in view of non-availability in the
required quality and volumes. The cheaper availability of man made synthetic non-
woven fabrics in the international market has been dominating over expensive
cotton and leather based materials.
Also where leather scrap and leather board has been cheaper such as in India there
has been many problems like thickness variation, complicated process in-
consistency etc. As a result toe puff, counter and insoles, made of indigenously
generated non-leather materials has emerged as major drawback for producing
components consistently. The presence of banned chemicals like PCP, Benzodine,
AZO etc. also poses problems in leather or leather board materials produced in
India.
The present inventors have found that jute which is a natural fiber available in
abundance in India and Bangladesh and also cheap, high strength, and eco-friendly
could be processed into useful material for footwear application.
It has, therefore, been the main object of the present invention to make effective use
of jute for products used in the various footwear components.
It is a further object of the present invention to produce footwear accessories by the
use of jute fabrics or jute mixed with other fiber/fabrics.
Yet another object of invention is to reduce the cost of such footwear components at
the user's end by way of cost-effective replacement of leather, synthetic and cotton
based footwear components presently in use, without compromising on the quality.
Yet further object of the invention is to produce jute composite or mixed fiber
composites in the shape of semi finished sheet materials and finished components
which are cut to shape and size for its ready use in footwear.
Yet another object of the invention is to provide an antistatic insole/fabric material
for use in footwear for the safety reasons on jute/cotton/mixed fabric, with or
without chemical treatments.
Thus the invention relates to a composite in the form of sheet, fabric and the like
for use in the manufacture of footwear components, said composite comprising jute
fibre/fabric optionally with cotton or other known natural or synthetic
fibres/fabrics, said fibres/fabrics being impregnated with emulsion and/or coated
with adhesive.
The jute fabric/fibres are in the form of fabric, non-woven jute fibres, a mixture of
fabrics and fibres and sandwitched fabrics.
The principal shoe components are toe puffs, counters, insoles and lining materials
Such components prepared by the composite according to the invention have
enhanced user properties. For toe puffs and counters the use of the composites
according to the invention are found to have enhanced bond strength, shape
stability, elongation and area shrinkage. For insoles produced by the components
according to the invention properties such as water absorption, water de-
absorption, flexing index/value, adhesion properties and tensile strength are
superior to the known components available in the trade and known in the field.
Depending on the type of footwear and its use the specific properties of the material
are determined for applications such as toe puffs, counters, insoles and lining
materials.
According to a preferred aspect of the invention jute non-woven or jute/cotton
weaved fabrics are impregnated in emulsion or coated with adhesive for the purpose
of obtaining stiffness in the materials. The formulation and the solid percentage of
the adhesive or emulsions are to be selected on the basis of requirements in the
finished sheet which is to be formulated as per the suitability of the footwear design
and requirement of the customer.
The adhesive used for the purpose of this invention is formulated with polystyrene
along with waste material of expanded polystyrene (popularly known as Thermocol),
solvents, fillers and plasticizers. The process for the preparation of the adhesive
comprises mixing of the said raw materials in a stirrer for about 3 hours. The
relative portions of the raw materials depends on specific applications.
The adhesive used for the composite for use in toe puffs and counters the following
formulation :
Polystyrene - 25 to 40% by wt., preferably 30 to 35% by wt.
Waste material - 10 to 25% by wt., preferably 15 to 20% by wt.
Plasticizers - 0.5 to 3% by wt., preferably 1 to. 2% by wt.
Filler - 5 to 25% by wt., preferably 10 to 20% by wt.
Solvent - balance
For achieving greater stiffness and thickness properties in the toe puffs or counters
solid materials in the formulation i.e. polystyrene, waste material and filler are used
in higher levels. Greater stillness is required lor toe puffs and counters for use in
footwear for the gents and those for defence use.
Common plasticizers available in commerce may be used lor the purpose of the
invention. The most preferred plasticizer is dioctyl phthalate (OOP).
Mineral powders are available commercially in diverse mesh size and may be used as
fillers. It is preferred to use filler of fine mesh. The most preferred mesh size is between
200-300 mesh. The preferred fillers are dolomite, calcite, talc. Other tillers with similar
properties may also be used.
The solvent used for the purpose of invention is selected from toluene, benzene,
ethyl acetate, acetone, methyl ethyl ketone. The most preferred solvent is toluene
and ethyl acetate.
The high impact polystyrene material having rubber content in the layer of 6-10% is
used in the formulation of the invention. Commercially available polystyrene may be
chosen. Polystyrene marketed by BASF, LG POLYMERS, SUPREME PETRO
CHEMICALS are most suitable.
The emulsion used for the purpose of the invention are commercially available. The
preferred ones are produced by using styrene monomer, talc, poly vinyl acetate (PVA),
styrene butadiene rubber (SBR) in different ratios depending on application. One or
more types of emulsions such as styrene, SBR, PVA etc. are mixed with suitable fillers
while formulating the emulsions used for fabric impregnation. Their ratio depends on
the applications and the fillers are used for impregnation. Suitable emulsions are
produced by M/s Pidilite Industries, India and Bayer AB, Germany and are suitable for
the purpose of the invention.
The fabric impregnated with emulsions / coated with adhesives is cut into desired
shapes by standard means. The cut components before application are dropped in
solvent for activation of adhesives properties.
Some manufacturers do not prefer the solvent dip process but prefer a hot melt
process in which the impregnated fabric is further coated with hot melt adhesive.
The material thus obtained is cut into desired shapes for their use. The cut
components in this case are subjected to heating for activating the adhesive
properties.
Jute fiber and fabrics have very good strength and compatibility with rubber,
plastics and thermoplastic hot melt adhesive. A suitable combination with these
materials could lead to better shape retention, strength, mouldability, moisture
absorption and de-absorption, flexibility and like apart from considerable cost
reduction and easy availability of raw material due to strong presence of jute crop
in India and Bangladesh.
It is thus possible by way of this invention to provide jute composites for various
footwear components following simple and cost effective process of manufacturing
such as :
a. jute composite impregnated fabric for use in toe puff by solvent dip process
b. jute composite impregnated fabric for use in Counter stiffener by solvent dip
process
c. impregnated fabric as stated in (a) and (b) above coated with hot melt
adhesive for using in toe or counter by heat setting process
d. extruded film lamination of hot melt on impregnated a and b fabrics above
for filmic - ping pong properties.
e. jute Composite fabrics impregnated in chemicals and/or sandwitch
laminated fabrics for use in insoles in different thickness
f. cut and skived components for its ready to use.
According to one embodiment the invention, the process for the manufacturing of
the composite fabric according to the invention comprises :
i) providing non-woven and/or woven fabric of jute and optionally cotton and
other fibrous material;
ii) impregnating the fabric with an emulsion or coated with an adhesive on one
or both sides of the fabric;
lii) curing the impregnated fabric under heating ;
iv) cooling the fabric.
Both the emulsion impregnated and adhesive coated fabrics are suited for toe
and/or counter applications and can be wound in roller form or cut to sheets. The
emulsion/impregnated fabric of required thickness is also suitable for insoles. The
adhesive coated fabrics are however not preferred for insoles. For thicker insoles
two layered laminated sandwiched sheets are formed. In the invention razed or
brushed jute fabric have resulted in better properties.
In accordance with another embodiment one side of the impregnated fabric is
coated with hot melt adhesive. Such hot melt coated fabrics are most suitable for
producing toes and counters.
In accordance with a further embodiment the impregnated fabric is provided with a
coating of extruded film on the fabric (the filmic ping pong type for toe puff).
The impregnated fabrics according to the present invention is provided in roll or in
sheet form which are then cut to desired shapes. The components thus produced
are used as such or duly skived on the edges of the toe or counter. For insoles the
unit shape is further moulded and fitted with shank in a separate line in a
conventional manner.
Standard impregnation machines/stenters are used to carry out impregnation and
drying of the fabric. The commonly used machines are marketed under the
tradenames Bruckner, Isotex, Harish. The halt adhesive coating is made standard
equipments which are commercially available and some popular names are
NORDSON, ROBTECH and PRIMEC.
The end products namely toe puff, counter and insole of different constructions are
made from composite fabrics according to the invention and impregnated in types of
specially formulated emulsions for stiffness. These fabrics are either supplied in
rolls of standard sizes or in sheets of standard sizes packed in bundles or pellets.
Such stiffened fabrics are cut to shape according to desired sizes. The hot melt
adhesive coated stiffened fabrics are supplied in sheet form.
The invention also covers the production of finally shaped components i.e. toe puff,
counters or insoles which are produced as per the pattern supplied by the
customers and are sold in volume of pairs.
The details of the invention, its objects and advantages are illustrated hereunder in
greater detail in relation to the non-limiting embodiments shown in the
accompanying figures wherein :
Fig. 1 is a flow diagram of the manufacturing process for providing impregnated
fabrics for the toe puff, coating and insoles.
Fig. 2 is a flow diagram of the manufacturing process of hot melt adhesive coating
on impregnated fabric for use as thermoplastic toe puffs and counters.
Fig. 3 is a flow diagram of manufacturing cut and shaped components of toe puff,
counters and insoles.
Fig. 1 shows an equipment in which process of impregnated fabric for toe puff-
counters and insoles is effected. The calendar rolls and chiller rollers are added to
the aforesaid standard machines by the manufacturers and this is a well known
technique in the trade. In the flow diagram of Fig. 1 a standard equipment is shown
which has the following components :
1. Fabric unwinder
2. Emulsion Tank for emulsion impregnation
3. A pair of squeeze rollers for removing excess material
4. Drying chamber fitted with rollers, heaters, exhaust, blower, radiators etc.
5. Three bowl Calendar rolls for surface Finish and thickness control
6&7. Bowl Chilled Rollers for cooling the heated fabrics.
8. Shearing machine for sheet cutting in required sizes.
9. Winder for roll packing
3 0. Stacker
Fabrics are first put on the unwinder 1 in roll form which is passed through the
emulsion tank 2 for impregnation in the required volume. The tank 2 is equipped
with two dip rolls for impregnation of the required volume of emulsion in the fabric.
The impregnated fabric are then passed through the squeeze rolls 3 to control the
excess impregnated material and then enters the heating chamber 4 for curing of
emulsion at the required temperature. The chamber 4 is designed to have rollers
from inlet to outlet and fitted with heaters, air blower, exhaust, radiators etc. with
the control panel for temp control. The heated fabric coming out from the chamber
are passed through the 3 bowl chrome plated calendar rolls 5 for polishing, uniform
surface and thickness. As the fabric remains heated with tack properties it is
therefore passed through the chilled rolls 6 and 7, to cool them in total. The
impregnated fabric can now be supplied in sheet or by cutting them in the required
length on the shearing machine 8 or in rolls formed by winder 9. When sheets are
formed the same is stacked on a stacker 10.
The impregnated fabric obtained from the steps shown in Fig. 1 is used for further
application or subjected to hot melt adhesive coating on the machine shown in the
fig. 2 for producing thermoplastic type materials.
Fig. 2 shows an equipment in which process of hot melt adhesive coating on
impregnated fabric for use as thermoplastic toe puff and counters are carried out.
In the process diagram of Fig. 2 a standard equipment is shown having the
following main components :
1 1. Fabric Unwinder
12. Stand with roller for web tension
13.Adhesive tank with heating system
14&15. Roller with knife coating head
16&17. A pair of bowl Chilled cooling roller
18.Sheet Cutter
19.Stacker stand for sheets
20. Winder for making rolls
The impregnated fabric coming out from the machine shown in Fig. 1 in roll form is
put to unwinder 11 of the machine shown in Fig. 2. The fabric is then passed
through the stand 12 fitted with rolls for controlling the web tension and then
enters the adhesive coating stand 13 attached with the melting tank for regular flow
of adhesive to roller with knife coating head 14. The fabric coated with adhesive is
passed through the knife 15/rolls for controlling the thickness and then put
through a pair of bowl chrome plated chilled rollers 16 & 17 for cooling the adhesive
and remove surface tack. The sheet emerging from the roller 16&17 may be wound
in the winder 20. If cut sheets are desired then sheets are formed by sheet cutter 18
and the sheets are stacked on stacker 19.
For reverse coat the fabric is wound on the roller after first side coat and then
reversed on unwinder for coating the other side.
For filmic type toe puff : EVA/polyester or polyamide based adhesive is coated on
one side by using extrusion coating machine (single/co extrusion) instead of using a
melt tank as shown in fig. 1 above.
The equipment shown in Fig. 3 carries out the process of manufacturing cut and
shaped components of toe puff - counters and insoles. The machine of Fig. 3 is of
beam press type and is provided to cut the sheets for making components in the
required shape and size. The machine shown in Fig. 3 have the following main
components :
21. Motor
22.Presser
23. Switch
24.Impregnated fabric sheets
25. Press
26.Clicking die
27.Machine base with oil tank
The emulsion impregnated/adhesive coated sheets are subjected to cutting to
desired sizes and shapes in the machine of Fig. 3. The motor 21 is activated by
switch 23 and in turn the press 25 is pushed by the presser 22 and imparts presser
orr clicking dies 26 which in turn cuts the sheets 24 to produce components of
desired shape and size. In the same operation a plurality of sheets 24 may be used.
The machine based 27 as an oil tank provided therein. The beam press produces
components using multiple number of sheets as per the thickness and the
properties.
Samples produced by the process of the invention have been tested and the test
results are shown in Tables I and II.
Table I shows data in respect of a sample of solvent activated stiffener sheet
impregnated with emulsion 1.2 mm for toe and counter.
TABLE I
Test Methods : SATRA PM 83 : 1996 and SATRA AM 1 : 1992; SATRA PM 31 : 1997
A : for industrial and high quality footwear, B: for town and fashion comfort shoes,
C : for inexpensive and light use footwear.
This stiffener material is considered as medium hardness category suitable for
industrial and high quality footwear as far as 1 - 4 tested properties is concerned.
Toluene is used as solvent. Dipping time 5 seconds. Drying time to evaporate
surface solvent 60 seconds.
Table II shows data in respect of a sample of solvent activated stiffener sheet coated
with adhesive on both sides for stiff counter.
TABLE II
Test Methods : SATRA PM 83 : 1996 and SATRA AM 1 : 1992: SATRA PM 31 : 1997
A : for industrial and high quality footwear, B: for town and fashion comfort shoes,
C : for inexpensive and light use footwear.
This stiffener material is considered as very hard hardness category suitable for
industrial and high quality footwear as far as 1 - 4 tested properties is concerned.
Toluene is used as solvent. Dipping time 5 seconds. Drying time to evaporate
surface solvent 60 seconds.
It is clear from the tables 1 and II that the jute composite produced according to
present invention has the required properties and is most suitable for use as
footwear components.
The machinery and raw materials and specification disclosed herein are only by way
of illustration and not to the limit the invention. Variations of raw materials and
specification including the machinery are included with the scope of the invention.
CLAIM
1. A Jute composite in the form of sheet, fabric for the manufacturer of footwear
components like toe puff, counters and insoles, said composite comprising jute
fibre / fabric with natural and synthetic fibres / fabrics, said fibres / fabrics being
impregnated with emulsion and / or coated with adhesives,
wherein the adhesive used for producing sheet materials for toe puff and counters
has the following formulations:
Polystyrene : 25 to 40% by wt.
Waste / Jute caddies : 10 to 25% by wt.
Plasticizer : 0.5 to 3% by wt,
Fillers : 5 to 25% by wt,
Solvent : Balance
2. A composite as claimed in claim 1, wherein the adhesive has preferable the
following formulation:
Polystyrene : 30 to 35% by wt.
Waste / Jute caddies : 15 to 20% by wt.
Plasticizer : 1 to 2% by wt,
Fillers : 10 to 20% by wt,
Solvent : Balance
3. A composite as claimed in Claim 1, wherein the emulsion is prepared by combing
styrene monomer, talc, poly vinyl acetate and styrene butadiene rubber.
4. A composite as claimed in claim 1 & 2, wherein the plasticizer is dioctyl
phthalate (DOP).
5. A composite as claimed in claim 1 & 2, wherein filler is selected from dolomite,
calcite, talc.
6. A composite as claimed in claim 5, wherein the filler has mesh size of between
200-300 mesh.
7. A composite as claimed in claim 1 & 2, wherein the solvent is selected from
toluene, benzene, ethyl acetate, acetone, methyl ethyl ketone.
8. A composite as claimed in claim 1 & 2, wherein the polystyrene has rubber
content in the layer of 6-10%.
9. A process for the manufacturing of the composite fabric as claimed in claim 1,
comprising the steps of:-
i) providing non-woven and / or woven fabric comprising jute and natural
fibrous material;
ii) impregnating the fabric with an emulsion or coating with an adhesive on
one or both sides of the fabrics;
iii) curing the impregnated fabric under heating;
iv) cooling the fabric,
10. A process as claimed in claim 9, wherein the impregnated fabric is subjected to a
hot melt adhesive coating,
31. A process as claimed in claim 10, where in the impregnated fabric is coated with
hot melt adhesive on one side,
12. A process as claimed in claim 10, where in the impregnated fabric is coated with
hot melt adhesive on both sides,
13. A process as claimed in claim 10, wherein the impregnated fabric is provided with
a coating of extruded film on the fabric.


A Jute Composite in the form of sheet, fabric for manufacture of footwear components
like toe puff, Counter stiffener and Insoles, said composite comprising jute fibre / fabric
with natural or synthetic fibres / fabrics, said fibres / fabrics being impregnated with
emulsion and / or coated with adhesive,
wherein the adhesive used for toe puff and counters has the following formulations:
Polystyrene : 25 to 40% by wt.
Waste / Jute caddies : 10 to 25% by wt.
Plasticizer : 0.5 to 3% by wt,
Fillers : 5 to 25% by wt,
Solvent : Balance
Wherein the emulsion is prepared by combing styrene monomer, talc, PVA and SBR,

Documents:

493-cal-2000-abstract.pdf

493-cal-2000-cancelled pages.pdf

493-cal-2000-claims.pdf

493-CAL-2000-CORRESPONDENCE.1.3.pdf

493-cal-2000-correspondence.pdf

493-cal-2000-description (complete).pdf

493-cal-2000-drawings.pdf

493-CAL-2000-EXAMINATION REPORT.1.3.pdf

493-cal-2000-examination report.pdf

493-CAL-2000-FORM 1.1.3.pdf

493-CAL-2000-FORM 13.1.3.pdf

493-CAL-2000-FORM 18.1.3.pdf

493-CAL-2000-FORM 3.1.3.pdf

493-CAL-2000-FORM 5.1.3.pdf

493-cal-2000-form-1.pdf

493-cal-2000-form-13.pdf

493-cal-2000-form-18.pdf

493-cal-2000-form-2.pdf

493-cal-2000-form-3.pdf

493-cal-2000-form-5.pdf

493-CAL-2000-GRANTED-ABSTRACT.pdf

493-CAL-2000-GRANTED-CLAIMS.pdf

493-cal-2000-pa.pdf

493-cal-2000-reply to examination report.pdf

493-cal-2000-specification.pdf


Patent Number 247520
Indian Patent Application Number 493/CAL/2000
PG Journal Number 16/2011
Publication Date 22-Apr-2011
Grant Date 13-Apr-2011
Date of Filing 28-Aug-2000
Name of Patentee ALMAL MANI SHANKAR
Applicant Address APL POLYFAB PVT. LTD., 48C, MATHESWARTOLLA ROAD, CALCUTTA
Inventors:
# Inventor's Name Inventor's Address
1 ALMAL MANI SHANKAR APL POLYFAB PVT. LTD., 48C, MATHESWARTOLLA ROAD, CALCUTTA-700046
PCT International Classification Number D06N3/04
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA