METHOD FOR TREATING A TEXTILE

Abstract: A textile is treated with a processing composition com­ prising (1) a water-soluble polymer having carboxyl groups and (2) a crosslinking agent having at least two groups re­ active with the carboxyl groups before processing the treated textile with a cationic emulsion.

Description: The present invention relates to a method for treating a textile by using a textile processing composition comprising a water-soluble polymer having carboxyl groups and a crosslinking agent having at least two groups reactive with the carboxyl groups. Heretofore, a variety of functional emulsions have been used in differentiation of textile products. Usually, textiles are negatively charged in water, so that it is thought that cationic emulsions are adsorbed more easily on textiles and provide uniform processing and they are actually used more frequently. In processing a thick cloth with a cationic emulsion, however, the emulsion particles are forced to move toward the inside by capillarity during dewatering after the processing (centrifugal dewatering or mangle squeezing) and no emulsion particles are allowed to remain on the surface of the cloth. Therefore, no function can be imparted to the surface of the cloth in such a case, thus resulting in incomplete processing. This phenomenon gives rise to a serious problem in differentiation such as shade improving or water-repellent processing. Further, it sometimes happens that other processings are carried out incompletely, though unintentionally. Essentially, no satisfactory function can be imparted to textile in processing unless the emulsion particles are uniformly adsorbed on the textile. However, incomplete processing often occurs in conventional textile processing because treatments such as continuous processing, dipping, or spraying are carried out without complete knowledge of the interaction between textile and a finishing agent. Particularly, it is very difficult to treat a thick cloth so that both of its surface and inside are uniformly processed, because of the above-mentioned permeation into the inside. Therefore, although cationic emulsions which can be easily adsorbed on textiles are frequently used, it is not possible to effect uniform processing of a thick cloth. DE-A-31 51 451 disclosed a method for dying a textile made of synthetic fibers with disperse dyes wherein an aqueous dye dispersion is used which besides the disperse dye contains a synthetic thickening agent containing carboxyl groups and a natural thickening agent on basis of polysaccharides wherein the treating dispersion has a pH of 1,2 to 4,5. However, the process disclosed therein does not enable an uniform processing of a textile, in particular when it is a thick cloth. Therefore, the object of the present invention is to provide an improved method for treating a textile which solves the above problems. As a result of extensive studies to achieve the above object of the present invention it has been found, that it is possible to effect uniform processing of a textile, even when it is a thick cloth by treating the textile product with a textile processing composition comprising a specific water-soluble polymer and a specific crosslinking agent in a specific ratio followed by heat-treating the obtained textile and then processing it with a cationic emulsion. Subject-matter of the present invention is a method for treating a textile by using a textile processing composition comprising a water-soluble polymer having carboxyl groups and a crosslinking agent having at least two groups reactive with the carboxyl groups, which is characterized in that it comprises the following steps: (a) treating the textile with an aqueous composition containing in a concentration of 0,01 to 10 wt.%, calculated as the solids of at least one water-soluble polymer having carboxyl groups selected from the group consisting of acidic polysaccharides, alginic acid, polyacrylic acid, polymaleic acid, polymethacrylic acid, vinyl acetate/maleic acid copolymers, vinyl acetate/arylic acid copolymers, polyvinyl alcohol/maleic acid copolymers, acrylate/acrylic acid copolymers, acrylic acid/maleic acid copolymers and the water-soluble salts and the water-soluble partial salts thereof, and of at least one cross-linking agent selected from the group consisting of polyglycidyl ethers, epoxy compounds, polyaldehydes, polyols and polyamines, wherein the weight ratio of said water-soluble polymer to said cross-linking agent being in the range of from 1:0,001 to 1:30, (b) heat-treating the textile to cross-link the water-soluble polymer with the cross-linking agent and fix the cross-linked polymer on the surface of the textile and (c) then processing the treated textile with a cationic emulsion. According to a preferred embodiment of the present invention said textile processing composition is attached to the textile in an amount of 0,01 to 10 wt-% in respect to the solid. As cationic emulsion in step (c) of the above process of the present invention preferably a color-deepening agent is used. According to a further preferred embodiment of the present invention additionally a water-repelling agent, antistatic agent, water and sweat-absorptive processing agent, hand builder and/or a resin processing agent is used. The water-soluble polymers having carboxyl groups which can be used according to the present invention include any of naturally occurring and synthetic polycarboxylic acids selected from acidic polysaccharides such as pectic acid and its salts, alginic acid and its salts, polyacrylic acid, polymaleic acid, polymethacrylic acid, vinyl acetate/maleic acid copolymers, vinyl acetate/acrylic acid copolymers, polyvinyl alcohol/maleic acid copolymers, acrylate/acrylic acid copolymers, acrylic acid/maleic acid copolymers, and water-soluble salts thereof (including their partial salts). In is of course possible to apply further water-soluble polymers containing carboxyl groups other than the above-mentioned. The crosslinking agents having at least two carboxyl groups which can be used in the present invention include polyglycidyl ethers such as ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, and glycerin triglycidyl ether; epoxy compounds such as haloepoxy compounds such as epichlorohydrin and X-methylchlorohydrin; polyaldehydes such as glutaraldehyde and glyoxal; polyols such as glycerin, pentaerythritol, and ethylene glycol; and polyamines such as ethylenediamine, among which the epoxy compounds are preferred. It is of course possible to use further crosslinking agents other than the above-mentioned. The ratio of the water-soluble polymer having carboxyl groups to the crosslinking agent varies with the kind of the used polymer or of the used cross linking agent, within the range of from 1:0,001 to 1:30, preferably 1:0,01 to 10 by weight. A textile product can be treated with the textile processing agent of the present invention by any desired method such as one in which a textile product is dipped in a solution of 0,01 to 10 wt.% of the processing agent, one comprising dipping treatment, and one in which a textile product is sprayed with the solution. Thereafter the textile product is heat-treated after the treatment under a condition suited for each fiber material, fiber form and dyeing state. By effecting the above treatment with the processing agent of the present invention, the water-soluble polymer is crosslinked with the crosslinking agent and fixed on the surface of the textile in the form of a crosslinked polymer. The textile processing agent is preferably attached to a textile product in an amount of 0,01 to 10 wt.%, particularly preferably 0,05 to 5 wt.% in therms of solids. The textile processing agent of the invention can be applied to any fibers, that is, natural cellulose fibers such as cotton and linen, regenerated cellulose fibers such as viscose rayon and cuprammonium rayon, natural animal fibers such as wool and silk, synthetic fibers such as polyester, acrylics and polyamide (nylon) and semisynthetic fibers such as acetate. Although the processing agent can be applied to any form of fiber, such as staple, tow, cheese and cloth, it can exhibit its effect of pretreatment most markedly especially upon a thick cloth. Finally, a textile product which has been treated with the textile processing agent is processed with a cationic emulsion. By this it is possible to effect uniform processing even when the textile product is a thick cloth. For example, when a dyed cloth pretreated with the textile processing agent of the instant invention is processed with a shade-improver (a cationic emulsion) as disclosed in JP-B-29 682/82 and 139 885/82, a remarkably excellent color-deepening effect can be obtained. The cationic emulsions which can be used according to the present invention are not particularly limited. Exemplary of suitable emulsions are color-deepening agents (cationic emulsions) as described in JP-A-29 682/1982 and JP-B-139 885/1982. In addition, there can be mentioned water repelling agents, antistatic agents, water and sweat-adsorptive processing agents, hand builders, and a variety of resin processing agents. The condition for processing with a cationic emulsion is not particularly limited. It can be freely selected according to the emulsion used. Although the mechanism by which uniform processing can be attained in the process of the present invention is not necessarily clarified, it might be considered that introduction of carboxyl groups into textile serves to increase the interaction between the textile and a cationic emulsion and make uniform processing possible. However, its details are not clear as yet. In any case, it has become possible to attach a cationic emulsion uniformly also to a thick cloth by the processes of the present invention. It is not critical whether the cloth to be pretreated with the processing agent according to the present invention is an undyed cloth or a dyed cloth. That is to say, any of the following processes can be used: 1) dyed cloth → pretreatment → aftertreatment, and 2) undyed cloth → pretreatment → aftertreatment → dyeing. The dyeing can be performed by any of dipping, textile printing, and continuous dyeing. Concerning the aftertreatment, the function of the surface of a cloth is important. Although the effect of the pretreatment with the processing agent of the present invention is marked especially when the processing is performed with a color-deepening agent, a water-repelling agent or the like, complete and uniform processing becomes possible by carrying out the pretreatment with the processing agent of the present invention even in the case of a processing other than these mentioned above. The present invention will now be described in detail with reference to examples. Example 1 Polycarboxylic acids shown in Table 1 were synthesized according to a usual manner. A polyester cloth was treated with a textile processing agent comprising a polycarboxylic acid shown in Table 1 and a crosslinking agent (Denacol EX-313®, a product of Nagase & Co. Ltd., glycerol polyglycidyl ether), and the ζ potential of the cloth was measured. The results are shown in Table 2. [ Condition of treatment ] A bath containing 5 g/l of a polycarboxylic acid and 0.5 g/l of the crosslinking agent was prepared, and a polyester cloth was padded with the bath, squeezed to 100 % owf, and dried at 100°C for 5 minutes. It was cured at 150°C for 3 minutes. [ Condition of ζ potential measurement ] The measurement was made by using a commercially available device for measuring a streaming potential (a product of Shimadzu Seisakusho Ltd). A 0.001 N KCl solution (pH 7) was used as a streaming solution. Table 2 shows that when cloths are treated with the textile processing agents of the present invention, the treated cloths show markedly increased ζ potentials. Example 2 A black cloth was obtained by dyeing a thick polyester cloth (basis weight of 500 g/m²) as deeply as possible. The dyed cloth was pretreated in the same manner as in Example 1, and then treated with a color-deepening agent TR-420®, (a cationic agent available from Kao Corporation), and the shade-improving effect on the treated cloth was measured. Results are shown in Table 3. [ Condition of processing with a color-deepening agent ] A bath containing 40 g/l of TR-420® was prepared, and a dyed, pretreated cloth was padded with the bath, squeezed to 100 % owf, dried at 100°C for 5 minutes, and further cured at 150°C for 3 minutes. Table 3 shows that when cloths are pretreated with the textile processing agents of the present invention, they exhibit an excellent color-deepening effect and their durability is excellent. Example 3 Cloths were treated with textile processing agents under the following condition of dipping and then processed with a color-deepening agent TR-420®. The color deepening effect of the processed cloths were measured. The results are shown in Table 4. [ Condition of dipping ] A bath containing 1 g/l of a polycarboxylic acid and 0.1 g/l of a crosslinking agent was prepared. A black polyester cloth was placed in the bath, treated at 60°C for 30 minutes, dewatered, and dried. [ Condition of color-deepening ] pad-dry-cure process similar to that in Example 2 Example 4 Thick cloths of polyester, nylon, and cotton were each treated with a textile processing agent and then processed with a cationic water-repellent. The water repellencies of the processed cloths were measured. The results are shown in Table 5. [ Condition of treatment with a textile processing agent ] pad-dry-cure process treating solution: 5 g/l of a polycarboxylic acid and 1 g/l of a crosslinking agent [ Condition of processing with a cationic water-repellent ] pad-dry-cure process processing solution; 20 g/l of a commercially available product A Table 5 shows that when textiles are pretreated, all of them can show an excellent repellency to water. On the contrary, the water repellency is poor when textiles are processed with a water-repellent only.

Claims: A method for treating a textile by using a textile processing composition comprising a water-soluble polymer having carboxyl groups and a crosslinking agent having at least two groups reactive with the carboxyl groups, characterized in that it comprises the following steps: (a) treating the textile with an aqueous composition containing in a concentration of 0,01 to 10 wt.%, calculated as the solids, of at least one water-soluble polymer having carboxyl groups selected from the group consisting of acidic polysaccharides, alginic acid, polyacrylic acid, polymaleic acid, polymethacrylic acid, vinyl acetate/maleic acid copolymers, vinyl acetate/arylic acid copolymers, polyvinyl alcohol/maleic acid copolymers, acrylate/acrylic acid copolymers, acrylic acid/maleic acid copolymers and the water-soluble salts and the water-soluble partial salts thereof, and of at least one cross-linking agent selected from the group consisting of polyglycidyl ethers, epoxy compounds, polyaldehydes, polyols and polyamines, wherein the weight ratio of said water-soluble polymer to said cross-linking agent being in the range of from 1:0,001 to 1:30, (b) heat-treating the textile to cross-link the water-soluble polymer with the cross-linking agent and fix the cross-linked polymer on the surface of the textile and (c) then processing the treated textile with a cationic emulsion. The method according to claim 1, in which said processing composition is attached to the textile in an amount of 0,01 to 10 wt.% in respect to the solid. The method according to claim 1 or 2, in which as cationic emulsion a color-deepening agent is used. The method according to any of claims 1 to 3, in which additionally a water-repelling agent, antistatic agent, water and sweat-absorptive processing agent, hand builder and/or a resin processing agent is used.

Inventors: NAKASHIMA, NORIHIKO
Applicants: KAO CORPORATION
Application year: 1985
Main classification: D06M15
IPC codes: D06M15, D06M13