US3547750A - Method of stiffening loops of a fabric and product - Google Patents

Description

United States Patent C) 3,547,750 METHOD OF STIFFENING LOOPS OF A FABRIC AND PRODUQT Jean Bussac, Regny, France, assignor to Anciens Etablissements .lalla, Paris, France, a body corporate No Drawing. Filed Mar. 8, 1967, Ser. No. 621,428 Claims priority, application France, Mar. 17, 1966, 53,865; Dec. 20, 1966, 88,128 Int. Cl. D0311 27/08 US. Cl. 161-66 Claims ABSTRACT OF THE DISCLOSURE A new kind of pile fabric in which the small loops or so-called terry loops are stiffened by having deposited thereon an emulsifiable thermoplastic resin containing a substantial amount of triazine and a soluble salt of a metal of Group II of the Periodic Table of elements, the stiffened loops permitting the utilization of the fabric for a number of purposes in which high rubbing friction is required. The invention also includes a method of stiffening the loops.

The present invention is directed to a novel looped pile fabric which is characterized in that the loops are stiffened over at least part of the surface of the fabric. The invention is also directed to the different articles which can be manufactured with the novel fabric, especially articles used for rubbing purposes, such as towels, face cloths and gloves, dish-cloths and floor-cloths, carpets, conveyor-belts or other similar articles which can be employed to exert friction or withstand repeated rubbing during use. The invention also comprises a method for the manufacture of fabrics and articles having stiffened terry loops.

Terry loop fabrics are well known and are suited to a number of different uses; generally speaking, soft and supple terry loops are not intended either to withstand more or less energetic rubbing or to exert friction. The present invention provides an unexpected and highly useful technical improvement as a result of the creation of a new kind of looped pile fabric in which the terry loops have a degree of hardness which permits the utilization of the fabric for a number of different purposes in which more or less high rubbing friction is required.

The invention has the additional advantage of per mitting the ready and economic conversion of a looped fabric of known type to a fabric having stiffened loops. The method according to the invention makes this conversion possible both on the fabric itself and on articles which have already been made such as, for example, bath towels, face-cloths, gloves, rugs and carpets, and so forth; the method can also be applied to the entire surface of the fabric or article, or alternatively to only one portion or selected portions of this surface. Thus, the novel fabric can have stiffened loops on only one face or on both faces.

The fabric and the articles in accordance with the invention can be obtained from all conventional looped fabrics whether woven or knitted, for example the fabrics commonly known as Turkish towelling, and particularly textile materials formed of cellulose fibres or containing such fibres. Among other fabrics which are suitable for this purpose, mention can be made of those 3,547,750 Patented Dec. 15, 1970 which are formed of mixed textile yarns, such as cellulose yarns (cotton, linen) and animal yarns (wool, silk) and/or cellulose and synthetic yarns (nylon and the like).

By way of example, the articles in accordance with the invention can be bath towels, one face of which is untreated and therefore soft and absorbent whereas, on the other face, all or part of the terry loops are stiffened, which makes it possible to utilize this face of the towel for rubbing purposes. Another example consists in the treatment of face-cloths of the glove type, in which only the outer face is provided with hardened terry loops, with the result that the users hand is in contact with the soft internal face of the glove fabric; consequently, gloves of this type are very pleasant both to wear and to handle. One application which illustrates the stiffening of loops on both faces of the fabric is the manufacture of rugs and carpets, in particular mats for dogs.

The method according to the invention consists in depositing on the loops to be stiffened an aqueous suspension of an emulsifiable thermoplastic resin containing triazine and a soluble salt of a metal of Group II of the Periodic Table of elements, and in drying the loops thus treated.

Preferably, the suspension utilized also contains a finishing resin of known type.

By way of emulsifiable thermoplastic resins, mention can be made of the acrylic, methacrylic and/or vinyl resins which are particularly suitable. Thus, successful use can be made of commercially available aqueous emulsions of polyacrylates of methyl, ethyl, butyl etc., of the corresponding polymethacrylates, of acrylomethacrylic copolymers such as, for example, a copolymer of ethyl and of methyl methacrylate; polymers of this type are found in commerce under trade names such as Perapret F, Ucecryl PO, and others.

Excellent results are also obtained with aqueous emulsions of polymers or copolymers such as polyvinyl acetate, or alternatively polyvinyl formate, propionate or chloride; also suitable for the purpose are the emulsions 0f the copolymer of polyvinyl chloride and polyvinyl acetate. Suitable vinyl resins are marketed under the trade-marks Rhodoplas, Afcolac, Mowilith, etc.

The salt of a metal of Group II of the Periodic Table of elements which serves as catalyst can be, for example, a chloride, sulphate, nitrate, perchlorate, chloroacetate etc. of zinc, beryllium, magnesium, calcium or any other alkaline-earth metal.

As regards triazine, it is possible to employ the technical product of the type which is marketed under the trademark Stabitex D 46 and which contains approximately 50% triazine.

As concerns the finishing resin, which is a highly desirable addition agent in the suspension, such a resin is advantageously selected from the polyethers of ethylene-glycol or polyoxy-ethylene compounds, and particularly useful is a diester of a condensation product of formaldehyde with ethylene glycol; thus, diglycol-formal diacetate is especially suitable.

It may prove useful also to add to the suspension a known thickening agent such as, for example, the watersoluble condensation product obtained by the reaction of urea and formaldehyde, a polyvinyl alcohol or the like.

Although the composition of the suspension can vary over a fairly wide range depending on the required degree of stiffening of the loops, the nature of the resin and of the fabric to be treated, and also depending on other conditions, the proportions of constituents indicated above are usually of the order of:

G. Emulsifiable thermoplastic resin 10 to 150 Triazine 2 to 80* Finishing resin 2 to 25 Thickening agent to 10 Metal salt 2 to 20 as expressed in dry substance per liter of suspension. Preferably, the proportion of thermoplastic resin is approximately 40 to 55% of the total constituents except water.

The foregoing indications are not given in any limiting sense.

The aqueous suspension can be applied on the looped fabric by any known means such as coating, spraying or impregnation. The spray atomization system is of particular interest and highly convenient in practice, especially in the form of either one or a number of feed-racks which are employed for the purpose of spraying very small droplets of the suspension onto the fabric. The operation is usually performed on looped pile fabric which has undergone bleaching followed by drying after delivery from the loop.

The quantity of suspension to be employed per square meter of fabric varies according to the nature of the fabric, the composition of the suspension and the degree of stiffening which is sought. As a rule, the quantity is of the order of 50 ml. to 800 ml. per square meter of surface but, in the majority of cases, varies between 100 and 300 ml.

After the desired quantity of suspension has been applied to the loops, the fabric is subjected to a drying process which can take place at any temperature which is compatible with the heat resistance of the textile being processed and the constituents employed; the drying process can be performed, for example, between room temperature and 200 C., but rapid drying without causing damage to the material is obtained preferably between 100 and 15 0 C. In the vicinity of 15 0 C., only a few minutes are required for the loop fabric to be ready for use.

The examples which now follow are intended to provide explanatory illustrations of the invention, but are not given in any sense by way of limitation.

EXAMPLE 1 With a view to converting terry-cloth bath towels (of Turkish towelling material) to rubbing-down towels, 1 liter of aqueous suspension was sprayed onto 5 square meters of this fabric, that is to say onto towels, and was prepared as follows:

30 g. of emulsion containing 50% polyvinyl acetate known by the trademark iRhodopas were admixed with 7 g. of commercially available diglycol-formal diacetate known by the trademark Knittex POM 60, with 10 g. of 50% triazine (trademark: Stabitex D 46), 5 g. of a thickening agent having a urea-formaldehyde base (known as Texapret S) and 5 g. of 90% magnesium chloride.

The quantity of water added to this mixture was such that the final volume was 1,000 ml.

The suspension obtained therefore contained the following proportions per liter as expressed in dry substance:

G. Polyvinyl acetate Diglycol-formal diacetate 3.5 Triazine 5 Urea-formaldehyde 2.8 Magnesium chloride 4.5

After this suspension had been applied on the towels, the latter were then dried by passing through an oven for a period of 3 minutes at 140 C. After cooling by air blast on delivery from the oven, the towels were ready for use as rubbing-down towels, the terry loops having been perfectly stiffened.

4 EXAMPLE 2 An aqueous suspension was sprayed on a thick cotton terry-cloth fabric in a proportion of 0.1 liter per square meter; the suspension contained per liter:

g. of copolymer of ethyl acrylate and methyl methacrylate,

70 g. of triazine,

20 g. of zinc nitrate,

these materials being measured in the dry state.

The treated fabric was dried in an air stream at approximately l10130 C.

There was thus obtained an article with well-stiffened loops and affording high resistance to friction, which was particularly well suited for either wet or dry cleaning of floors and the like surfaces.

EXAMPLE 3 A suspension which was similar to the one described in Example 1 Was prepared with 17.5 g. of polyvinyl acetate instead of 15 g. It was employed for the purpose of coating looped pile carpets on both sides and in a proportion of 0.25 liter per square meter. Drying was effected at 150 C. in approximately three minutes.

The hardened-loop carpets thus obtained had high resistance to wear.

EXAMPLE 4 Carpets such as those of Example 3 were manufactured in the same manner and using a similar suspension in which polyvinyl acetate was replaced by 23 g. of methyl polyacrylate.

EXAMPLES 5 to 8 Number of Example N0. Products omitted washings Triazine 10 6- Magnesium chloride. 10 7. Diglycol-iormal diacetate 14 8. Urea-formaldehyde 150 1 None 300 Thus, when triazine and magnesium chloride are not present, there is no stiffening of loops which are treated with polyvinyl acetate; these two adjuvants produce a certain degree of stiifening, even if the finishing resin (diglycol-formal diacetate) is not present, as is shown in Example 7, but the resistance to washings is in that case fairly low (14). Example 8 shows that the omission of thickening agent reduces resistance to washings to a small extent compared with Example 1. In the final analysis, it can be seen that triazine and the magnesium salt are essential and that the finishing resin is very important in order to obtain loops of sufficiently permanent stiffness.

What is claimed is:

1. A pile fabric having stiffened loops, which contains in the dry state, per square meter, 0.5 to grams of a thermoplastic material selected from the group consisting of polyvinyl acetate, polyvinyl formate, polyvinyl propionate, polyvinyl chloride, copolymer of vinyl chloride with vinyl acetate, lower alkyl polyacrylate, lower alkyl methacrylate and copolymer of ethyl acrylate with methyl methacrylate, and 0.1 to 64 grams of triazine.

2. A fabric according to claim 1, which contains in the dry state, per square meter, 1 to 45 grams of polyvinyl acetate, and 0.2 to 24 grams of triazine.

3. A fabric according to claim 1, which contains in the dry state, per square meter, 1 to 45 grams of ethyl acrylate and methyl methacrylate copolymer and 0.2 to 24 grams of triazine.

4. A method of stiffening loops of a fabric, which consists in depositing on the loops an aqueous suspension of a thermoplastic material selected from the group consisting of polyvinyl acetate, polyvinyl formate, polyvinyl propionate, polyvinyl chloride, copolymer of vinylchloride and vinyl acetate, lower alkyl polyacrylate, lower alkyl polymethacrylate and copolymer of ethyl acrylate with methyl methacrylate, containing triazine and a salt selected from the group consisting of zinc, beryllium, magnesium and calcium as metal component and chlorides, sulfates, nitrates, perchlorates and chloroacetates, as anion component; said suspension containing per liter 10 to 150 grams of the thermoplastic material, 2 to 80 grams of triazine and 2 to 20 grams of the salt; and then drying the fabric at a temperature which does not exceed 200 C.

5. The method according to claim 4, wherein said suspension contains per liter 2 to 25 grams of a finishing resin selected from the group consisting of polyethers of ethylene-glycol, polyoxyethylenes and diesters of a condensation product of formaldehyde with ethylene-glycol.

6. The method according to claim 5, wherein the drying temperature ranges from 100 C. to 150 C.

7. The method according to claim 4, which consists in spraying onto the loops an aqueous suspension containing, per liter, 10 to 150 grams of polyvinyl-acetate, 2 to 80 grams of triazine, 2 to 20 grams of a salt selected from the group consisting of magnesium chloride, magnesium nitrate, zinc chloride and zinc nitrate, 2 to 25 grams of diglycol-formal diacetate and to grams of water soluble urea-formaldehyde resin, the weight of polyvinyl acetate constituting about 40 to 55% of the total weight of the components of the suspension other than water, while the weight ratio of the polyvinyl acetate content to the triazine content is between 1.5 and 5, and in then drying the fabric at a temperature of 100 to 140 C.

8. The method according to claim 4, which consists in spraying onto the loops an aqueous suspension containing, per liter, 10 to 150 grams of ethyl polyacrylate, 2 to 80 grams of triazine, 2 to grams of a salt selected from the group consisting of magnesium chloride, magnesium nitrate, zinc chloride and zinc nitrate, 2 to grams of diglycol-formal diacetate and 0 to 10 grams of water soluble urea-formaldehyde resin, the weight of ethyl polyacrylate constituting about 40 to 55% of the total 6 weight of the components of the suspension other than water, while the weight ratio of the ethyl polyacrylate content to the triazine content is between 1.5 and 5, and in then drying the fabric at a temperature of 100 to 140 C.

9. The method according to claim 4, which consists in sprayin onto the loops an aqueous suspension containing, per liter, 10 to 150 grams of methyl polymethacrylate, 2 to 80 grams of triazine, 2 to 20 grams of a salt selected from the group consisting of magnesium chloride, magnesium nitrate, zince chloride and zinc nitrate, 2 to 25 grams of diglycol-formal diacetate and 0 to 10 grams of water soluble urea-formaldehyde resin, the weight of methyl polymethacrylate constituting about 40 to of the total weight of the components of the suspension other than water, while the weight ratio of the methyl polymethacrylate content to the triazine content is between 1.5 and 5, and in then drying the fabric at a temperature of 100 to 140 C.

10. The method according to claim 4, which consists in spraying onto the loops an aqueous suspension containing, per liter, 10 to 150 grams of ethyl acrylate and methyl methacrylate copolymer, 2 to grams of triazine, 2 to 20 grams of a salt selected from the group consisting of magnesium chloride, .magnesium nitrate, zinc chloride and zinc nitrate, 2 to 25 grams of diglycol-formal diacetate and 0 to 10 grams of water soluble urea-formaldehyde resin, the weight of ethyl acrylate and methyl methacrylate copolymer constituting about 40 to 55% of the total weight of the components of the suspension other than water, while the weight ratio of the ethyl acrylate and methyl methacrylate copolymer content to the triazine content is between 1.5 and 5, and in then drying the fabric at a temperature of to C.

References Cited UNITED STATES PATENTS 2,590,713 3/1952 Libbey 26-2 2,609,350 9/1952 Spatt l17161UHE 2,678,924 5/1954 Graulich et a1. 26029.6EMN 2,780,562 2/l957 Reinartz et a1. 26029.6EMN 2,940,863 6/1960 Bennett et a1. 117l6lUHE WILLIAM J. VAN BALEN, Primary Examiner R. H. CRISS, Assistant Examiner US. Cl. X.R.