AU687343B2

AU687343B2 - New and improved backing for textiles

Info

Publication number: AU687343B2
Application number: AU30408/92A
Authority: AU
Inventors: Roy Harold Blood; Patrick Devlin; Peter John Murray
Original assignee: FELTEX MODULAR CARPETS Pty Ltd
Current assignee: FELTEX MODULAR CARPETS PTY Ltd
Priority date: 1991-07-05
Filing date: 1992-12-23
Publication date: 1998-02-26
Anticipated expiration: 2012-07-03
Also published as: ZA939679B; AU3040892A; CN1090347A; WO1994015008A1

Description

AUSTRALIA

Patents Act COMPLETE SPECIFICATION

(ORIGINAL)

Class Int. Class Application Number: Lodged: Complete Specification Lodged: Accepted: Published: Priority Related Art: 6 Name of Applicant: Feltex Modular Carpets Pty. Ltd.

Actual Inventor(s): Roy Harold Blood Patrick Devlin Peter John Murray Address for Service: PHILLIPS ORMONDE FITZPATRICK Patnt and Trade Mark Attorneys 367 Collins Street Melbourne 3000 AUSTRALIA Invention Title: NEW AND IMPROVED BACKING FOR TEXTILES Our Ref 314086 POF Code: 100/127567 The following statement is a full description of this invention, including the best method of performing it known to applicant(s): 6006 6006 2 NEW AND IMPROVED BACKING FOR TEXTILES This application is a divisional application of International Patent Application PCT/AU92/00329 ("the parent application"). The parent application describes and claims an improved backing material which is particularly useful in the manufacture of tufted textiles such as carpets. One embodiment of the invention described in the parent application concerns the impregnation of a backing material with a suitable polymeric material so to stabilise the backing or 1 i 41 part _trr^ 4o tufting operation. The present applicationA e sfeGis this embodiment and the products so produced and outlines various benefits and advantages achieved through the stabilization of a backing material, especially in the manufacture of carpet.

More specifically, this invention relates to a matrix formed from a fibrous, substantially inert material for use as a backing suitable in the manufacture of S 20 various tufted textile materials. The invention has application not simply in relation to carpets but in other applications where the stability and integrity of the matrix is important. The backing material may for instance be used in geotextiles, synthetic playing surfaces (such as tennis courts) and in fabrics used in S" wall coverings, seat coverings and the like. The invention is hereafter discussed in connection with carpets and carpet tiles but should not be taken as restricted in its application to such products.

S" 30 A large number of carpet tiles are sold each year.

They generally comprise a thermoplastic backing into which a carpet yarn, such as wool, is tufted. Traditional thermoplastic backings include polypropylene or polyester fibres which can be in the form of solid sheets or woven material. Generally, they comprise a non woven random layered web of thermoplastic material partially melted to provide a backing sheet material. Needles are used to force the yarn through the thermoplastic backing.

It is common then to apply a support layer compriped yT^ so 3 of fibreglass in the form of a non woven random layered sheet. The fibreglass sheet is generally coated with a binding material such as a PVC resin or the like. The carpet is then cut into tiles.

It has been found that carpet tiles so produced tend to lift at the edges particularly after printing. The edges curl upwards to make the floor unattractive and the tiles unacceptable. Thermoplastic backing materials respond in this way due to creep over time or due to elastic memory in the material after the punching operation. Accordingly, it has been standard practice to apply an adhesive to the backing of the tiles to keep them flat and secured to the flooring over which they are laid. Similar problems arise with other tufted fabrics.

In the past, it has also been practiced in some cases to deform carpet tiles mechanically to stretch the backing layer in an effort to keep the tile flat. This is not always possible and is a labour intensive procedure.

In any event, it is usually only partially successful in removing the tendency of the edges of the carpet tiles to lift.

Over the years, many attempts have been made to *o solve the problems believed to be inherent in the manufacture of tufted fabrics but without success.

The present invention provides a fabric backing for tufted textile materials such as carpet tiles and other carpets but allows for the manufacture of tufted products that have acceptable dimensional stability and flatness such that for example, the carpet can be laid onto floors without the need for adhesives.

The invention is based on the realisation that the penetration of the thermoplastic backing material by tufting needles introduces dimensional instability into the backing causing shrinkage to occur during subsequent processing. The invention provides a construction where this effect is minimised or avoided.

Thus, in accordance with the present invention there is provided a penetrable fabric backing material comprising a matrix formed from fibrous, substantially 4inert material wherein said fabric is stabilized by treatment of the matrix to the extent necessary so to bind sufficient of the fibres of the matrix together so that it remains substantially dimensionally stable on a needle punching operation in those portions not immediately exposed to the said punching operation, yet retains sufficient flexibility so to allow it to pass around rolleru in a textile manufacturing process.

It will be appreciated that the treatment of the matrix must be moderated to achieve a backing which has the required flexibility yet dimensional stability.

Various treatment methods may be utilized in the performance of this invention which are suitable to bind the fibres of the matrix together. The appropriate treatment depends upon the nature of the matrix material *used. Suitable inert materials for use in this invention include silica fibres suci as fibreglass, mineral fibre, carbon fibre, steel fibre, keviar and similar such materials. Glass fibre fabrics are preferred. it is not necessary that the matrix material be formed entirely from the one material and it is not necessary that all material used within the matrix is inert although preferably at least 70% of the matrix material is formed from inert material. In one embodiment of the invention, the backing 25 material is a woven 100% fibreglass fabric. In another embodiment of the invention, the backing is a woven fibreglass fabric wherein at least one thread in five in both the warp and weft directions is formed from a polymeric material such as polypropylene or a polyester.

The fibreglass thread within such a woven fabric may be formed with multi filament fibreglass thread, The thread may be between 40 and 80 tex. A 66 tex fibreglass thread has been found particularly satisfactory as has a fabric woven with a double weft and Single warp thread.

A single warp and weft woven construction has been found particularly satisfactory although it should be appreciated that more complex warp and weft thread constructions may be employed. F~or example, 2 x 2 and 3 x 3 warp and weft copstructions have been found to be satisfactory.

It has been found that a thread density of between 7 and 5 threads per centimetre, that is between 17.5 and 12.5 threads per inch, both warp and weft Provides a suitable thread density. It has also been found that if the thread density is too high there is an increased possibility of needle damage and yarn breakage but that if the thread density is too low, there may be insufficient strength in the backing material. It is preferred that the woven weight of the backing be between 80 to 150 2 g/m 2has'proven particularly satisfactory.

More than one layer of the inert matrix material may be employed as the carpet backing as will be appreciated 1~ by those skilled in the art. Additional layers provide additional strength where this may be needed although it 06:4will be appreciated that where for example woven fibreglass material is being used, a single layer is satisfactory in most applications.

The backing of the present invention is treated so to stabilize it so that it will not dimensionally distort O *during the needle punching operation other than in those to OVportions immediately exposed to such punching operation.

to* The nature of the treatment depends to a certain extent on the inert matrix materia' being used. In most cases, a suitable polymeric or m:.,-ure of polymeric materials may O be used provided that they will stabilize the inert matrix 0b while permitting it to remain sufficiently flexible so to pass around rollers during manufacture and penetrable to allow tufting needles to pass through it.

Yr the case of fibreglass fabric, the treatment may Le ach 4~ed through heating so to meld various fibres together oe by impregnation with a suitable polymeric materidl. P1referahlyo the treatment comprises impregnation with a polymeric. material. Preferred materials are polyacrylic or polyacrylate resins; polyurethanes; formaldehyde resins such as urea or molamine formaldehyde and PVC latex. Other suitable resins will be appreciated by those skilled in the art.

6- Compatible blends of polymeric materials may also be used. For example, a blended polyurethane/acrylic resin is acceptable. Commerically available "acrylic" mixes are suite'ble and are sufficiently stable at processing temperati es. It is important to note that impregnation should occur and that a coating layer is not produced which would render the matrix too inflexible to be used in the manufacturing process, Where acrylic materials are used, they may include one or more acrylic polymers or copolymers of acrylic acid, and acyrlic acid esters such as butyl acrylate, ethyl acrylate or methyl methacrylate, for example. These ,yrlic polymers preferably have a molecular weight of between 50,000 and 250,000 and a viscosity in the range of from 50 to 1000 CPS, Whatever polymeric material is used, it is usually desirable also to add a surfactant to provide increased penetration of the material into the backing matrix material. Fillers such as calcium carbonate may also be included if desired.

Where polymeric materials are used to impregnated the inert matrix backing material, it is preferred that they are in solution or emulsified. An aqueous emulsion has been found to be particularly suitable with acrylic 25 resins in providing impregnation or penetration of fibreglass filaments, A suitable material available commercially is Primal T1R 407 manufactured by Rohm and Hass sold as a 45% solids aqueous emulsion.

The impregnating resin should be used in sufficient quantity in a woven fabric to bind both the warp and weft threads s'o to substantially prevent the threads of the weave slipping one over the other.

The stabilizing polymeric material may be applied by passing the matrix backing material through a bath containing the stabilizing polymeric mixture to obtain a satisfactory impregnation. However, other application methods have beon Eound to be satisfactory, Where a polymeric stabilizing material is used, it is preferred that it is present in a quantity of up to 20%. in the -7 weight of the final product weight after impregnation.

Preferably, between 6 to 8% of the finished material weight is constituted by the impregnating stabilizing resin.

It has been found that the carpet backing of the present invention remains sufficiently flexible for the tufting needles to penetrate the backing without ripping the f ibres. The material is able to pass around rollers and be separable when cut into carpet strips or tile shapes. It is also thermally stable at processing temperatures employed in the carpet tile manufacturing processes.

The impregnated backing of the present invention provides a suitable backing for carpet manufacture. Using a standard tufting machine, a continuous width of backing may be tufted with carpet yarn which may be comprised by wool or synthetic material or a combination of wool and synthetic material for example. The tufting needles readily penetrate the backing of the present invention. A 1.9 metre wide tufting machine has been used with success.

A tufted backing may then have applied to it a binding coating layer which may be comprised for example by a PVC layer or other binding layer which binds the tufted yarn to the backing material. Suitable binding 2 layers will depend largely on the manner in which the 9 inert material is treated and the nature of the inert ni,'terial. It is important that the binder be compatible :with the treated matrix backing material. Where fibreglass is used as the matnix material impregnated with an acrylic or acrylate, it hao been found that a suitable binding layer includes PVC preferably in the form of a plastisol. PVC latex would be equally good. With the backing of the present invention, it is possible to use a binding coating layer of lower quality than was previously employed. This is possible because greater tension can be applied to the carpet thereby t o increase the penetration of the binding layer.

A support layer may also be applied. The support 8 layer may include a fibreglass material such as a non woven random layered fibreglass sheet bound with an acylic resin as is known in the art, A further coating of a binding layer may be applied thereto to complete the carpet construction.

In a preferred method of construction, the backing of the present invention is tufted in a tufting machine to form a carpet strip. In a treatment machine, a binding layer is applied to a support backing, a support layer is supplied to the binding layer as it passes therethrough, a further binding layer is applied to the support layer and then the carpet strip applied thereto with the backing adjacent the binding layer, The laminated strip is then passed to an over for curing. Subsequently, the carpet strip may be cut into narrower strips or tile shapes as *0 desired and printed by dyeing processes as is known in the art.

In one embodiment of the present invention, a 66 tex multi filament glass fibre was woven in a 1 x 1 warp and weft construction to produce a woven fibreglass material having a thread density of between 5 and 7 threads per :centimetre in the warp and weft direction and a woven weight of about 109 g/m 2 it was cut into a strip having a width of 1.9 25 metres. The Cibreglass fabric was dipped through an impregnation bath containing a Primal Tfl 407 being a 9solids aqueous emulsion. The impregnated fibreglass backing was then cured and formed into a backing roll.

The backing roll was then mounted onto a standard tufting machine. It was found that the backing material was particularly suitable for use in a standard tuftino machine and a tuf ted carpet strip produced. in the manner hereinbefore outlined, the binding layer and support layer structure was produced in which the binding layer comprised polyvinyl chloride and plastisol. The viscosity was 5000 CPS (Brookfield), The support layer comprised a non woven fibreglass material.

The laminated structure was cured in a curing oven.

9 After cooling, the carpet strip was cut into carpet tiles and printed using standard dyeing procedures. The carpet tiles so produced were placed onto a floor following standard procedures. It was found there was no tendency for the edges to raise and the carpet tile structure gave the appearance of a iled carpet structure. It was found that at the edges of the carpet tile there was no fraying and threads of fibreglass material were not evident.

Thus, in accordance with the present invention it is possible to produce a tufted carpet tile structure which is dimensionally stable and which can be placed onto floors using standard proceedures witnout risk of raising of carpet tile edges and fraying, It will be appreciated that many variations and modifications may be made to the above described "'so construction, and choices of materials may be varied without departing from the ambit of the present invention, oo So o* 0 0 0. 9A Throughout the description and claims of this specification, the word '(comprise" and variations of the word, Such as "comprising" and "comprises", is not intended to exclude other additives, components, integers or steps.

A a *06 R

Claims

1. A penetrable fabric backing material comprising a matrix formed from fibrous, substantially inert material wherein said fabric is stabilized by treatment of the matrix to the extent necessary so to bind sufficient of the fibres of the matrix together so that it remains substantially dimensionally stable on a needle punching operation in those portions not immediately exposed to the said punching operation, yet retains sufficient flexibility so to allow it to pass around rollers in a textile manufacturing process. 'SL QAhk¢k\[

2. A fabric as claimed in claim I wherein said Ainert material is formed from silica fibre. SU6a4(01/ esee t

3, A &bric as claimed in claim 2 wherein said =Azi=-- is Or comprl'ses fibreglass.

4. A fabric as claimed In claim 3 wherein said substantially inert material comprises a minor portion of S"a polymeric material 20

5. A fabric as claimed in claim 4 wherein said polymeric material is chosen from either polypropylene or a polyester.

6. A fabric as claimed in any one of the previous claims wherein said Inert material is in the form of a woven fabric,

7, A fabric as claimed in claim 6 wherein said fabric is comprised of woven fibreglass thread of between 40 and taex.

8. A fabric as claimed in claim 7 wherein said fabric is of a single warp and single weft construction.

9. A fabric as claimad in any one of claims 6 to 8 wherain said fabric has a thread density of between 5 and 7 threads per contimetre, warp and weft and a woven weight of between 80 to 150 g/m

10. A fabric as claimed in any one of bthe previous claims wherein said stabilizing treatment or tomrtuS heat treatment. Ii.

A fabric as claimed in any one of claims 1 to wherein said stabilizing treatment i or comprises 11 impregnation of the fabric with a stabilizing amount of one or more suitable polymeric materials.

12. A fabric as claimed in claim 11 wherein said polymeric materials are one or more of the resins selected from polyacrylic or polyacrylate resins, polyurethane, formaldehyde resins corp urea or melamine formaldehyde and PVC latex.

13. A fabric as claimed in claim 12 wherein said fabric is impregnated with a stabilizing amount of a polyacrylic or polyacrylate resin.

14. A fabric as claimed in claim 13 wherein said fabric is formed from a woven silica fabric having warp and weft threads and said fabric is impregnated with a stabilizing amount of polyacrylic or polyacrylate resin whereby to bind said warp and weft threads so to _sbilize said woven fabric to allow penetration by needles during a tufting S process.

A fabric as claimed in any one of claims \9 to 14 wherein an aqueous emulsion of the resin is employed. 20

16. A fabric as claimed in any one of claims 12 to wherein said resin is one or more polymers or copolymers of acrylic acid, an acrylic acid ester or methacrylic acid S""ester. l0e

17. A fabric as claimed in claim 16 wherein said polymer or copolymer has a molecular weight of between 50,000 and 250,000 and a viscosity in the range of from 50 to 100 cps.

18. A tufted textile material a fabric backing as claimed in any preceding claim, tufted with yarn usir. tufting needles, a support layer and a binding layer therebetween.

19. A tufted textile material as claimed in claim 18 wherein said fabric backing has been stabilized by treatment with a polymeric material and wherein said binding layer is chemically compatible with the resin used to so stabilize the fabric backing material.

A textile material as claimed in either one of claims 18 or 19 wherein said support layer is a web of non woven fibreglass.

21. A textile material as claimed in any one of claims N)N 12 18 to 20 wherein said binding layer is a polyvinyl chloride binding layer.

22. A carpet comprised of a tuftad textile material as claimed in any one of claims 18 to 22. in the form of a carpet strip.

23. A carpet comprised of a tufted textile material as claimed in any one of claims 18 to 21 in the form of a carpet tile. DATED: 23 December, 1992 PHILLIPS ORMONDE FITZPATRICK Attorneys for: FELTEX MODULAR CARPETS PTY. TI 5065W APSTRAQJ A penetrable fabric backing material comprising a matrix formed from fibrous, substantially inert material wherein said fabric is stabilized by treatment of the ivatrix to the extent necessary so to bind sufficient of the fibres of the matrix together so that it remains substantially dimensionally stable on a needle punching operation in those portions not immediately exposed to the said punching operation, yet retains sufficient flexibility so to allow it to pass around rollers in a got* textile manufacturing process, sees Is I.: