AU6373473A - Non-woven fabrics - Google Patents

Description

3 1.

MICROCOr'? RESOLUTION TEST CHART NATIONAL OFSTANDARDS BUREAU -1963

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4W INSTRUCTIONS

If lC fetlCt

no L D OUROCILLA~S DOLL~~..

±We IMPERIAL CHEMICAL INDUSTRIES LIMITED.

of Imperial Chemical House, Milibank, London, England. f**f

hereby apply for thc grant of a Patent for an invention entitled C I-e C' I) I ITI 'd) CCI u tfl nf

"IMPROVEMENTS IN 01P RELATING TO NON~-WOVEN FABRICS"

which is described in the accompanying (e complete specification.

(Note: The following paragraph applies only to Convention applications) flit" ~~C~eotim This application is a Convention application based on the basic application(s) for a patent or similar protection identified by number, country, and filing date as follows:

fll daIti II M, I A( 11 .ft ft ft u

56676/72 United Kingdom December 8, 1972.

Address for Service: PHILLIP1S ORMONDE AND FITZPATRICK Patent and Trade Mark Attorneys 37-4I' ueen Street Melbourne, Atustralia

Q)I11, C Dated December 17, 1973.

00 PHILLIPS ORMONDE FITZPATRICK Attorneys for:- CI, SIul, un-II IMPERIAL CHEMICAL INDUSTRIES requied IIh LIMIT

U- PHILLIPS, ORMONDE AND FITZPATRICK Patent and Trade Mark Attorneys Melbourne, Australia

1' AUSTRALIA Patent Declarations

'Sj-1 T -S SOLE INVENTOR

COMMONWEALTH OF AUSTRALIA

Patents Act

DECLARATION FOR A PATENT APPLICATION e

In support of the Convention application made by

IMPERIA, CHEMICAL INDUSTRIES LIMITED

(hereinafter called "applicants") for a patent for S an invention entitled It

I, Officer duly appointed, of Imperial Chemical Industries Limited, Imperial Chemical House, Millbank, London, England

do solemnly and sincerely declare as follows:

1. I am authorised to make this declaration on behalf of the applicants. **O

2. 'o

is the actual inventor of the invention and the facts upon which the applicants are entitled to make the application are as follows:

Applicants are the assignees of the said invention from the actual inventor.

3. The basic application(s) for patent or similar protection on which the application is based is/are identified by country, filing date, and basic applioant(s) as follows:

4. The basic application(s) referred to in paragraph 3 hereof was/were the first application(s) made in a Convention country in respect of the invention the subject of the application.

Declared at London, England.

Dated 5th D ember 19(3

(jjU^^s>

To: The Commissioner of Patents

DOCUMENTS LODGED WITH THIS APPLICATION ARE UNSUITABLE FOR REPRODUCTION AND MAY BE INSPECTED AT THE PATENT OFFICE A.C.T. COMMONWEALTH OF AUSTRALIA

Patents Act

COMPLETE SPECIFICATION (ORIGINAL)

Class 4nt-Cas

:*.Application Number: .0 -3 70"9-- 7--6 Lodged: i4- 73

OL2

'-7 Complhte Specification Lodged:/? 0*Accepted: 2-'qPS ~~Published: 1c 6- -7

:.Priority:

-6 662., Jtelated Art: :z7~ 16C/ t 4/ 5? Z-1/

1")

00000APPLICANT'S REF.: ICI CASE FO .25678 Ame(s) of Applicant(s): IMPERIAL CHEMICAL INDUSTRIES LIMITED

Address(es) of Applicant(s): England.

Actual Inventor(s): Michael Frank Culpin.

Address for Service is: PHILLIPS, ORMONDE FITZPATRICK Patent and Trade Mark Attorneys 37-41 Queen Street Melbourne, Australia, 3000 Complete Specification for the invention entit ed:

"IMP'ROVEMENTS IN OR RELATING TO NON-WOVEN FABRICS t

The following statement is a full description of this invention, including the best method of performing it known to applicant(s): I

i/ooc 1 1<-

The invention reoliten, to non-woven mi'teri-l1 ha:vi good

.moInin' ).Il1 stabllity and to a method oft m:aking them.

Non-woven materials composed of stanpl fibres !are known

nd have been used in such end-uses as floor coverings and upholstery

Sfabrics. However, in order to attain the necessary physical properties

tor such end-uses, in particular abrasion resistance, tear strength and

tensile strength, they h-ve had to be treated to effect inter-fibre *e bondiriy. Thus, it has been proposed to impregnate a web of staple

fibres with an idhesive material, such as a latex, or to incorporate

Smulti-component fibres in the fibrous web, said multi-component fibres having at least one component capable of being rendered adhesive in

a treatment which leaves at least one other component unaffected, the

S* potenti'.lly adhesive comoonent, which can be utilised to form bonds

between contiguous fibres, forming at least part of the surface of

the fibre. Because multi-component fibres can be intimately blended

with other fibres, bonding between fibres occurs throughout the

thickness of the fabric as a consequence the structure has improved

abrasion resistance and therefore this bonding method is preferred.

However, in domestic uses, such as in upholstery fabrics and floor

covers the dimensional stability of non-woven fabrics may not be adequate

when it is achieved merely through inter-fibre bonding.

Non-woven materials composed of continuous filaments are also known. The continuous filaments may have a multi-component

structure having a potentially adhesive comnonent which is utilised

to cause bonding between contiguous filaments. However, in many

cases the filunents may not be drawn and consequently will have a low initial modulus which makes materials made from such Iilamentn.

unsuitable for certain end-uses, such ui curtain mterials..

Proposals for increasing the dimensional stability of continuous

filament non-woven materials have included the incorporation of

warps of dimensionally st.ble threads, or stitch-bonding, in which

parallel rows of stitching are inserted along the length of the

material.

It has also been proposed to impart improved perform-nce,

dimensional stability, and tear strength, to non-woven

10' materials by incorporating within the thickness of the material a woven

scrim fabric, by forming a first web, laying the scrii fabric on the

first web, forming a second web on top of the scrim fabric and thereafter needle-punching the assemblage to unite the first and

second webs. ouch acrim-reinforced non-woven materials do indeed

possess improved properties compared with analogous non-woven

materials in which the scrim is omitted, but'it has been found that

their dimensional stability is still not adequate. Additionally

loops of the scrim material may be carried through the material by

the needles, giving rise to an unacceptable appearance, especially

if the scrim material is of a difference colour to the fibres of

the non-woven web. Examination of the scrim incorporated in this

type of scrim-reinforced non-woven material reveals that the

scrim miterial is damaged, a large proportion of the strands of the

material being diotorted so that they do not take any load, and

in some cases even severed, presumably as a result of the

needle-ounching operation, with the result that the dimensional stability of the material is lower than would be obtained with an undamaged scrim material.

We hive now found a method of producing a scrim-reinforced

non-woven material in which the scrim material is at most only

slightly dain-ged so that the product has improved dimensional

stability compared with prior art scrim reinforced non-woven materials.

Our invention therefore provides, in one of its aspects, a

method of producing a no.-woven material naving improved

dimensional stability, comprising forming a non-woven web

i0 from fibres at least a proportion of which can be activated

into an adhesive state, placing a woven scrim fabric on one side of

the said non-woven web and needle-punching the assemblage so

formed from the side opposite to that contacting the scrim fabric

in a needle loom equipped, and finally treating the needle-punched

assemblage to activate said potentially adhesive fibres to cause

bonds to form between fibres of which the non-woven web is comporsed

and between fibres and the scrim fabric.

The invention is applicable to non-woven materials made

from continuous filaments or from staple fibres. The word "fibre"

S.'CQ is to be construed in this specification as including continuous

filaments as well as staple fibres.

According to another embodiment of the invention there o is provided a non-woven material comprising a non-woven web of fibres or

filaments strengthened by bonds between contiguous fibres or filaments, and said material further strengthened by a scrim material attached to one f ce of said non-woven web by bonds formed between said scrim material and fibres or filaments oriented in planes perpendicular or substantially so to the plane of the fabric, said bonds being derived from at least some of said fibres or filaments.

The attachment of the scrim material to the back of the

non-woven material according to the method of the invention

surprisingly causes little distortion or damige to the scrim

m.terial and also ensures a surprisingly secure attachment of the

.2crim material to the non-woven material. Furthermore, there is

no possibility of loops of the scrim materiil to apnear on the

side opposite to the scrim so that an undyed scrim material can

be employed.

The method of the invention is aoplicable to any type of

non-woven material which can withstand the needling operation

whereby the scrim material is united to the non-woven material.

As previously mentioned, the non-woven material may be composed of

continuous filaments or of staple fibres. In the latter case, the

web of non-woven fibres may be needle-punched before the needle C

punching operation to unite scrim material to the non-woven material. *Oee

This nre-needling may have the function of cnnsolidating the amount

of fibres into a coherent web by fibre entanglemeiit or may have

the function of producing a surface texture comprised of a pattern

Sof tufts on the surface of the material. In the latter case, the

25o scrim material would preferably be applied to the back side of the

material, that is, the ornosite side to the textured surface. Such

tufted non-woven materials can be derived from a single non-woven

o55 5

e web, for example those in which the tufts irei rrtnged in parallel rows to give a simulated corduroy pattern, or from two non-woven webs laid one on the other, the tufts being composed predominantly from fibres originating in the non-woven web on the side remote from the tufts, that is on the back face of the non-woven web. Usi, this double web construction, interesting and aesthetically pleasing fabrics can be produced if the fibres in a first web differ in colour, deni.r, cross-sectional shape, etc, from fibres of the second web.

The gauge of the needles used to unite fibrous web and

scrim fabric will depend on the denier of the fibres of which the

fibrous web is composed, heavier gauge needles being reouired with

higher deniers than with lower deniers. The optimum needle gauge

will be readily determined by those skilled in the art. For example,

for staple fibre webs, we have found that needles having a gauge

number of aIt least 30, preferably at least 36, ire of most value with

6 denier fibres, but that 19 gauge needles are re.-uired with 30 denier

fibres. With continuous filament webs it may be necessary to use

heavier gauge needles than those which can be used with staple fibre

webs of the same denier. Generally, however, the gauge number of the

20 needles should be as large as possible, and will in any case be greater

than it yauge number of needles used to form patterns of tufts on a

surface of the webs when this is required.

The density of needle-punching, that is the number of

pentratons of needles through the non-woven miterial does not appear 0*

'2 to be critical, providing always that the density is sufficient to

o' c use thu scrim material to be attached to the non-woven mt"rial.

*6

o

We find th t a density of about 40 needle penetrations r r squlre

centimetre generally suffices.

It is necessary that a proportion of the fibres constituting

the non-woven material be cnoable of activation to an adhesive state.

Thus, the non-woven material may be composed of two species of fibres,

one of which is potentially adhesive under conditions which leive the

other non-activatable fibres unaffected. Multi-component fibres are

preferred -s the potentially adhetive fibres, for ex;anple bicomponent

fibres, said multi-component fibres having at least one component

which can be rendered adhesive under conlitions which leave at loant

one other comnonent unaffected, the potentially adhesive component

occupying at least part of the periphery of the fibre. The

activatable fibres may conveniently be thermoplastic, for example,

poly-imide, polyester or polyolefin, and tha n.n-activatable fibres

may be thermoplastic, thermoset, inorganic, or natural fibres ;uch

as wool or cotton, as desired. Preferably the potentially adhesive

fibres constitute at least 25% of the weight of fibres in the web,

although for some end-uses a lower proportion of such fibres is not

excluded.

20 The invention is further described non-limitatively in the

following Examples.

EXAMPLE 1

Two fibrous webs (designated Web A and Web B) were

vrepared as follows: e

5 Web A. Composed of an intimate blend of equal Dronortions

of 5 cm length, 6 denair nylon 66 fibres, with 5 cm length, 6 denier

biconmonent fibres having i core of nylon 66 surrounded by a sheath

**7 of nylon 6. All fibres were yed red aLnd were mechanically crimped by a stuffer-box crimper.

The blend of fibres were carded and cross-l'apoed on

conventional machinery to give a batt weighing 90 g m 2 The batt

was consolidated by a needle-ounching operation, usin.; 32 gauge

needles having 9 barbs, set to penetrate the batt to a depth of

13 mm. The batt was needled in a first pass to a density of 46 punches

per square centimetre (ppsc), and was then turned over and passed a

second tirre through the same needle loom where it received a furth'r

46 ppso, piving a total needling density of 92 ppsc.

Web B. The same blend of fibres was used to make Web 3,

and in the same manner, as Web A but its weight was 75 g and

the fibres were dyed yellow. The batt was needle-punched using

32 giuge, 5 barb needles to a total density of 60 ppsc, the needle

penetrxtion being 7 mm.

Web B was laid. on top of Web A, ind the assembly was

needle-punched from the top with 25 gauge 9 barb needles set to

penetrate tc a deoth of 1.5 cm. The density of needle-punching was

46 ppsc. In this way tufts of the yellow fibres of :eb 1 wore

-O rried by the needles through .feb A, to produce tufts of yellow ibr-s contrasting with the red background of Web A.

e. A scrim material was placed on the free surface of Web B.

The scrim m teriil comprised a fabric woven at a level of 6 Dicks n eor cm and 6 ends per cm, from ya-rns of 3 denier nylon 66 fibres,

the yari:; being 20's cotton couni. e oe o

-8-8

The assemblage was needle-punched from the face of Web A

using 36 gauge needles (9 barbs) at 92 punches ner cm2 with 1.23' cm

depth penetration.

The resultant :crim reinforced tufted material showed

firm ttachment of the scrim material with no visible damage thereto

nor distortion of the tufts.

Finally, the assemblage was passed through an oven in

which an 85' steam, 15' air mixture at a temperature of 230 0 C was

contacted with the web for 30 seconds, which treatment caused the

nylon 6 sheath comoonent of the fibre to become adhesive. On leaving the oven the sheath comnonent cooled, and bonds were form.d

between contiguous fibres.

EXAMPLE 2

This Example compares the properties of materials made

in accordance with the invention with prior art materials in which

a scrim miterial is incorporated within a bonded non-woven fibrous

material.

The Web A of Example 1 was prepared and a secondary batt e

of fibres was cross-laid on top of the Web A. The secondary ba't o

S 20 was a blend of equal pronortions of 5 cm length 6 denier nylon 66

S*fibres and 5 cm length 6 denier bicomponent fibres having a core

of nylon 66 surrounded by a sheath of nylon 6, both species being a

mechanically crimped in a stuffer-box crimper and dyed yellow.

2 The secondary batt weighed 75 gm

2" This fibrous assembly was passed through a needle-loom

and was needle-punched with 25 gauge, 5 barb needles set to penetrate a

16 ;nm, the needles first contacting the fibres of the secondA r'

batt ind carrying them through Web A so that a random pattern ,r

yellow tufts was formed on the surface of Web A. The density of

needle ounching was 46 ppsc.

Aiwoven scrim was next laid adjacent to the surface of the

secondary fibrous layer Lnd the assembly pissed through a needle-loim

eqjuipped with 32 gauge 9 barb needles. The needle penotration was

13 mm, and the needle density was 46 ppsc. 'The scrim miteri:il was

the same as that used in Example 1, namely comnosed of yarns of

3 denier nylon 66 fibres hiving a 20's cotton count, there being

6 picks and 6 ends per centimetre.

Finally, the assembly wis bonded by passing it through a

bonding oven in which it was subjected to an atmosphere of 85' steun,

air at a temperature of 23000C for 30 seconds. By this treatment

the nylon 6 sheath of the cibomponent fibres was rendered adhe .avo

and, on leaving the oven and cooling, bonds formed between contiguous

fibres.

The properti.s of this material according to the invention

are given in Table 1.

20 A prior art fabric was made from the same constituentisas *o

those described above in the following manner, for comoarison' purposes.

The woven scrim material was laid on the Web A and thereafter

2 the ;econdary batt of fibres (75 gm was cross-lapped on to the top

of the scrim on Web A. The assembly was needle-punched to form tufts

e of fibres from the secondary batt on the surface of Web A by carrying them through the ocrim material and through Web A. The needles, penetration and density were the samo as those used to form the tufts in the manufacture of the product according to the invention, namely gauge needles, 16 mm penetration and 46 ppsc. Thereafter the assembly was bonded as before. The properties of this material and also given in Table 1.

Table 1 Properties of fabrics incorporating a polyamide scrim material

Material according to Prior art material Property invention (scrim (fcrim incorporated material on back) within fabric)

2 Weight (gm- 256 277

Bending Length (cm) 8.5 8.4

15 Breaking Load (Kg) 12.8 10.5 o 0 Modulus Load (Kg) to produce extension of: C 5% 1.95 1.7 00 10f 4.1 3.4 *0 0 204 8.8 7.2 *e 0 0

Note (1) 0*

Meisured on an Instron (Hegistered Trade Mark) Tensile Tester on a 00 0 0 amrnrle me-uiring 2.5 cm x 20 cm.

0 11 *00*04

0

0

The materiatl accordin- to the invention seen to hwve

,mrroved modulus (ie resistance to dimension-change) and a higher

breiking load, whilst having a lower weight and a cc-, irrable bending

length, compared to the prior art f'abric.

:XA!YPUL 3 Example 2 was repeated, but a different scrim maiteriil was

used. In this Example the sorim material was composed of yarns of

rolyernter fibres, of 20's cot-ton count, there being 6 picks -and 6 ends ner centimetre.

The properties of the materials produced are given in

Table 2.

Table 2 Prooerties of fabrics incorporating a polyester scrim material

Material according to Prior art material Property invention (scrim (sorim inncrporated mAerial on back) within fabric)

W~eight (gmn-2 285 201

Bending Length (cm) 14.4 11.1

Breaking Load 8.4 Modulus Load to produce extension of: 511.7 10", 3.3 2.3 2Y,~ 5.1 4.9

12

S

*0

S.

Although lighter ind stiffer, the mtteri-l according to

the inveoit)on has a markedly higher breaiking, load aind ;,,odulinz thall

the itnT. a rt fabric.

&X(ViPLF 4 A quantity of 5 mm length, .tuffer-box crimped, 6 denier bicomoonent fibre having a core of nylon 66 and a sheath of nylon 6 was carded and cross-laid on top of a scrim materiail identical to

t .tt used in Example 1, The weight of' the cross-laid: b mtt of' fibres:

ws150 gui

The composite wais fed through a standard needle loorr 'i

ne.?dlo.d frorr above with 32 gauge 9 barb needles to a Tenetration of

16 mrm and a density of 46 ppsc.

The needled assembly was passed through a 854, ste-am 1< iir b-ndine oven at 2300C with a residence time of 24 seonds tocm

the sheaith compound to become adhesive and to flow and bond the web

and scrim maiteriail together.

""he scrim material was strongly adhered to the nori-wovon

ihnic ind the. 'orce re-ju-red to separate the two component

*m-asured to be 1.8 Kg/in in the longthwise direction o~tho fmbrii V nd1.4 Kg/ink across ths- Cabric.

is cnrl-a web weighing 150 gm, of th-a same comnosition

wn nedl(or at 13 innp-enetrition with 46 ppsc density ,,ith 32 rgauge,

Shrbn!o(C es. Thi-i webI -wis,laiid on the -ame ro-rim mteri-tl and

1 L 'L li throigh the b' ndinr7 oven without being needledi to fhe scrim -itri i! Thp idh,.-ion between rorim m-Lteri'1 mLn fibrous wec w.as so

ow tr, i t could not be meaisurod.

itXAMP"'

Example 4 was repeated, using i mixture of 50 OC ho

'bicomponent fibres with 5Mo of 6 denier 50 mm nylon 66 fibres. In

all other aspects the trial was identical to E~xample 4. After bonding a-force of 1.0 Kg/in in the lengthening

direction and 1.1 Kg/in in the crosswise direction was necessary to

separate scrim m~iterial from the non-woven component. 1~gain the

unneedled control could not be measured.

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Vt.

0 00

Claims (1)

1. THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS: WeEmTKSaOGGaWXlESXD

   1. A method of producing a non-woven mteri'Ll hiving improved

   dimensional stability, comprising forming a non-woven web from fibres

   at least a proportion of which can be aotivated into an adhesive

   state, placing a woven scrim fabric on one side of the said non-woven

   web and needle-punching the assemblage so formed from the side opposite

   to that contacting the scrim fabric in a needle loom and finally

   treating the needle-punched assemblage to activate said potentially

   adhesive fibres in order to cause bonds to form between the fibres

   of which the non-woven web is comnosed and between fibres and the

   scrim fabric.

   2. A method according to claim 1, wherein the formation of

   the non-woven web includes the steps of blending, carding and

   cross-lapping.

   3. A method according to claim 2 with the additional step of

   needle-punching.

   4. A method according to any preceding claim wherein the said

   fibres which can be activated into an adhesive state are multi-component

   fibres.

   S1 5. A method according to claim 4 wherein the multi-component

   Sfibres are bicomponent fibres.

   6. A method according to any preceding claim wherein the said S" fibres which can be activated to a potentially adhesive state

   constitute at least 25e of the weight of the fibres in the web.

   7. A method according to any preceding claim wherein the

   Sscrim material is composed of woven yarns of polyamide fibres.

   8. A method according to any one of claims 1 to 6 wherein

   the scrim ma.terial is comrosed of woven yarns of polyester fibres.

   9. A method according to any preceding claim wherein the

   fibres of which the non-woven web is composed hive a denier of 6

   and the needle loom is equipped with 30 gauge needles having a gauge

   number of 30 or higher.

   A method according to claim 9 wherein the web is subjected

   to at least 40 needle penetrations per square centimetre.

   11. A process of making a non-woven material substantially

   as described with particular reference to the 3xamples.

   12. A non-woven material comprising a non-woven web of fibres

   or filaments strengthened by bonds between contiguous fibres or

   filaments, and said material being further strengthened by a scrim

   fabric attached to one face of said non-woven web by bonds formed

   between said scrim fabric and fibres or filaments oriented in

   planes perpendicular or substantially so to the olane of the fabric,

   said bonds being derived from at least some of said fibres or

   filaments.

   *0 0 13. A non-woven material as claimred in claim 12 wherein said

   non-woven web comprises fibres oriented in planes perpendicular or

   substantially so to the plane of the web and extending beyond one

   surface thereof as tufts of fibres, said scrim material being 00 0 0 attached to the face opnosite to that exhibiting said tufts of fibres.

   14. A non-woven material as claimed in claims 12 or 13, wherein

   said bonds are derived from one component of multi-component fibres

   of which said non-woven web is comprised.

   A non-woven maiterial as claimed in claiti 141 wheriiin said.

   rnulti-component fibres are bicomponent fibres.

   16. .1 non-woven miterial as claimed in any one of cliimo; 12

   to 15, wherein said scrim fabric is composed of woven yarns of polywunide

   fibres.

   17. A non-w~i inaterial as claimed in any one of claims 12

   to 15 wherein said scrim fabric is composed of woven yarns of polyester fibrss.

   18. A non-woven material is claimed in any of claims 12 to

   17 wherein the fibres from which said bonds are derived constitute at least 2O" of the weight of the fibres of the non-woven web.

   19. A non-woven material substantially as described with refecrence

   to the E~xamples.

   DATED: December 17, 1973. PHILLIPS ORIVONDE FITZPATRICK Attorneys for:- IMPERIAL CHEMICAL INDUSTRIES LIMITED.

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