JP3369332B2 - Processing method of cellulosic fiber cloth - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing method for imparting easy care properties, permanent press properties, and shrink-proof properties to a fabric containing cellulosic fibers or a sewn product thereof. It is. 2. Description of the Related Art Cellulose-based fiber fabrics are subjected to gas phase processing using formaldehyde gas, and formaldehyde is cross-linked between cellulose molecules of the fibers.
(Wearability) is conventionally known, and is widely and generally performed. However, if sufficient easy care performance, permanent press performance, and shrink-proof performance are to be imparted to the fabric by this method, there is a problem in that the strength of the cellulosic fiber is greatly reduced. [0003] Further, after a water-soluble urethane prepolymer having a thermal dissociation type blocked isocyanate group at a terminal and having an alkylene oxide group in a main chain is applied to a cloth containing cellulosic fibers, the heat dissociation type blocked isocyanate group is added. There is also a method in which a water-soluble urethane prepolymer is polymerized by heat treatment at a temperature equal to or higher than the thermal dissociation temperature, and then gas phase processing is performed with formaldehyde to provide easy care performance while preventing a decrease in strength. In this case, even though the strength was maintained, the easy care performance was hardly satisfactory. This tendency is particularly noticeable when the basis weight of the fabric is 200 g / m ² or less and the mixing ratio of the cellulosic fiber is 50% or more. SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has excellent easy-care performance while minimizing a decrease in the strength of a fabric containing cellulosic fibers. It is a first object of the present invention to obtain a processing method that imparts permanent press performance and shrink-proof performance. Another object of the present invention is to obtain a processing method for imparting excellent form retention, puckering, and pleating retention to a sewn product of a fabric containing a cellulosic fiber while minimizing a decrease in strength. It is the purpose of. [0005] The present invention achieves the above object and has the following constitution. That is, the present invention provides a water-soluble urethane prepolymer having a thermal dissociation-type blocked isocyanate group at a terminal and an alkylene oxide group in a main chain and a free nitrogen group capable of reacting with formaldehyde in a fabric containing a cellulosic fiber. After applying the compound having the above, heat treatment is performed at a temperature equal to or higher than the thermal dissociation temperature of the above-mentioned thermal dissociation type blocked isocyanate group to polymerize the water-soluble polyurethane prepolymer, and then, if necessary, a sewn product is formed. The moisture percentage of the fabric is 1 to
The gist of the present invention is to provide a method for processing a cellulosic fiber cloth, which is characterized by performing a gas phase processing with formaldehyde which is uniformly adjusted to 50% and then adsorbs formaldehyde gas to the cloth and heat-treats and crosslinks. Hereinafter, the present invention will be described in detail. [0006] The fabric containing cellulosic fibers referred to in the present invention refers to a woven fabric, knitted fabric, non-woven fabric, or a woven, knitted or non-woven fabric comprising one or more fibers of ordinary cellulose such as cotton, hemp and rayon. It refers to a woven or knitted fabric made of a mixture of fibers and synthetic fibers such as polyester, polyamide, and polyacrylonitrile (blended, mixed, mixed, knitted, etc.). Of course, cellulosic fiber 10
A cloth made of 0% may be used. In the present invention, any of the above-mentioned fabrics is effective, but in particular, the basis weight is 200 g / m2.
² or less, the effect of the present invention is remarkably exerted on a fabric in which the mixing ratio of cellulosic fibers is 50% or more. In the method of the present invention, first, the above-mentioned fabric has a heat-dissociable block isocyanate group at the end and a water-soluble urethane prepolymer having an alkylene oxide group in the main chain and a free nitrogen group capable of reacting with formaldehyde. Apply compound. Here, as the water-soluble urethane prepolymer having a thermal dissociation-type blocked isocyanate group at the terminal and an alkylene oxide group in the main chain, one having a molecular weight of 1,000 to 100,000 may be used. The heat dissociation type blocked isocyanate group constituting the water-soluble urethane prepolymer is formed by blocking free isocyanate with sodium bisulfite, phenol, active methylene compound, lower alcohol, lactam, etc., and heating to 100 to 180 ° C. As a result, the blocking agent is dissociated, the isocyanate group is regenerated, and subsequently, the isocyanate group reacts to polymerize. Alkylene oxide is made of polyethylene oxide, polypropylene oxide, or the like, and gives water solubility to the prepolymer and gives permeability to cellulosic fibers. Compounds having a free nitrogen group capable of reacting with formaldehyde include compounds having an amide group such as urea and dicyandiamide, ethylene urea, propylene urea, 2-pyrrolidone, 2-oxooxalidine, pyrrole, imidazole, and the like. Examples thereof include nitrogen-containing heterocyclic compounds such as 1-methylimidazole, 1,2,4-triazole and indole. In order to apply the above-mentioned resin to a fabric, a urethane prepolymer and a compound having an amino group are dissolved in water, and if necessary, an aqueous solution containing a catalyst and a softener is impregnated into the fabric by a usual method. ,dry. Practically, it is preferable to control the amount of adhesion with a padder, a coater or the like. After applying the resin, in the present invention, the water-soluble polyurethane prepolymer is polymerized by heat treatment at a temperature not lower than the heat dissociation temperature of the above-mentioned heat dissociation type blocked isocyanate group. The heat treatment temperature in the polymerization reaction is 100-180 ° C
However, 130 to 150 ° C. is more preferable. When the reaction temperature is lower than 130 ° C., the dissociation of the blocking agent does not occur, and the polymerization becomes insufficient.
On the other hand, when the temperature exceeds 180 ° C., the polymerization is sufficient, but the fabric is yellowed and the whiteness is lowered, which is not preferable. Thereafter, a sewing product is formed as required.
Sewing may be performed by a normal method. In the present invention, the moisture content of the fabric is set to 1 to 5
Adjust uniformly to 0%. At this time, the moisture content of the fabric is 1 to
It must be 50% and the moisture must be evenly distributed in the dough. If the moisture content of the dough is less than 1%, the formaldehyde gas used in the next step will not be sufficiently adsorbed on the dough, and if it exceeds 50%, the dough may be embrittled by the acid catalyst. Be careful. If the moisture is not uniformly distributed in the dough, the formaldehyde gas will not be uniformly adsorbed. Although any means may be used to uniformly adjust the moisture content, a method in which a cloth or sewn product is usually left in a thermo-hygrostat for 24 hours or more is preferably used. After adjusting the moisture content, in the present invention, a formaldehyde gas is adsorbed on the cloth, and the cloth is subjected to a gas phase processing using formaldehyde to be crosslinked by heat treatment. At the time of gas phase processing, a gas phase processing apparatus having a normal-pressure closed reaction chamber, a formaldehyde gas supply unit and a heating unit can be used. In this case, ATP (American Textile
A gas phase processing device manufactured by Processing Co.) can also be used. The formaldehyde gas concentration in this vapor processing apparatus is preferably in the range of 1 to 20%, and if it is 1% or less,
Even if the cross-linking reaction becomes insufficient and becomes 20% or more, the effect is no longer improved. The catalyst used for the cross-linking reaction may be subjected to a gas phase treatment after padding the catalyst solution to the fabric in advance, or the catalyst solution or the liquefied catalyst may be vaporized or mist-adsorbed to the fabric. May be. Regarding the type of catalyst, when padding is performed in advance, the same catalyst as used in conventional resin processing, for example, a metal salt of an acid such as zinc nitrate, Lewis acid, Bronsted acid, or the like can be used. In the case of vaporization, an acid having a low volatile boiling point such as hydrogen chloride is desirable. The concentration of the catalyst is preferably in the range of 0.1 to 3.0% when treating with a gas. If the gas concentration is less than 0.1%, the crosslinking reaction becomes insufficient, and if the gas concentration becomes more than 3.0%, no further effect is obtained, and an excessive decrease in fabric strength occurs. When the catalyst is applied by padding with an aqueous solution, the catalyst concentration is 5 to 100 g.
/ Liter range is desirable. If the concentration is 5 g / l or less, the crosslinking reaction becomes insufficient, and
/ Liter or more, the further effect will not be obtained, and excessive decrease in fabric strength will occur. After adsorbing the formaldehyde gas, the cloth or its sewn product is subjected to a heat treatment to carry out a crosslinking reaction. The heat treatment at this time is performed at a temperature in the range of 100 to 180 ° C. and at 0.1 °
The crosslinking reaction can be completed by performing the treatment for 5 to 10 minutes. The present invention has the above configuration. According to the present invention, when a water-soluble urethane prepolymer and a compound having an amino group are impregnated and polymerized in a cellulosic fiber, the cellulosic fiber is converted into a urethane polymer and formaldehyde in a relatively large amorphous region. The amorphous region is protected by filling with a compound having a free nitrogen group capable of reacting with water, and when subjected to a gas phase processing with formaldehyde in such a state, the formaldehyde becomes a urethane polymer and a compound having a free nitrogen group in the urethane polymer. And cross-links with cellulose as a cross-linking agent with a longer molecular chain, so that there is ample room, resulting in less decrease in strength and excellent easy-care, permanent-press, and shrink-proof properties. Become. EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. The measurement and evaluation of samples in the examples were performed by the following methods. However, for the following (2) to (7), a sample drip-dried after washing 5 times according to JIS L-0217 (method 103) was used as a sample. (1) Tear strength JIS L-1096 (2) Permanent pressability JIS L-1096 (3) Easy care AATCC-124 (4) Shrinkproof JIS L-1096 (5) Shape retention AATCC -124 (6) Puckling AATCC-88B-1964T (7) Pleated retention JIS-1096 Example 1 Broad cloth made of 100% cotton fabric (80s for both warp and weft)
/ 2, weight 150g / m ² ), and after normal scouring, bleaching and mercerizing, immersed in an aqueous solution of the following formula 1 with a padder, padded with a 60% pickup, and dried at 110 ° C. Then, a heat treatment was performed at 160 ° C. for 2 minutes. Formulation 1 Elastron MF-9 10.0% (water-soluble urethane prepolymer, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) Elastron Catalyst 64 0.5% (tin chloride catalyst, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) Urine 10.0% Vicron 55R 3.0% (fatty acid amide-based texture adjuster, manufactured by Ichisha Yushi Co., Ltd.) PORON MF-5 2.0% (silicone-based texture adjuster, manufactured by Shin-Etsu Chemical Co., Ltd.) ) Reperon OPC 2.0% (polyolefin-based hand control agent, manufactured by Satoda Kako Co., Ltd.) By leaving this cloth in an environment room at a temperature of 20 ° C. and 65% RH, the moisture content is adjusted to 8.0. Adjust to%,
Subsequently, gas phase processing was performed as follows using a gas phase processing apparatus having a stainless steel reaction chamber having a width of 2 m, a length of 3 m, and a height of 2 m. First, the fabric was put in the processing apparatus, sealed, and supplied with a formaldehyde aqueous solution for 1.5 minutes through an injector and a steam conduit with steam at 1.2 kg / m ² and 105 ° C., and a 2,400 g aqueous formaldehyde solution was supplied. Was injected. Next, 6.8 kg of sulfurous acid gas was injected and immersed for 2 minutes, and then free formaldehyde and sulfurous acid gas not retained by the fabric were exhausted, and the room temperature was increased to 127 ° C., thereby achieving the gas phase processing of the present invention. A fabric was obtained. For comparison with the present invention, a work cloth for comparison (Comparative Example 1) was obtained in exactly the same manner as in this example except that urea was omitted from Formulation 1 in Example 1. The performances of the present invention and the work cloth for comparison were measured and evaluated, and the results are shown in Table 1. [Table 1] As is clear from Table 1, the processed fabric according to the present invention has a small decrease in strength, and also has excellent performance in easy care, permanent press and shrink resistance. Example 2 In Example 1 above, after processing according to Formula 1, but before adjusting the water content, a dress shirt was formed by sewing a fabric.
A sewn product of the present invention and a comparative product (Comparative Example 2) were obtained in exactly the same manner as in Example 1. The performances of the present invention and the sewn product for comparison were measured and evaluated, and the results are shown in Table 2. [Table 2] As is evident from Table 2, the sewn product according to the method of the present invention had a small decrease in strength, and also had excellent performance in form stability, puckering property, and pleating property. According to the method of the present invention, compared with the general vapor-phase processing using formalin, a sufficient permanent material can be obtained in the case of a cloth while sufficiently suppressing the reduction of the dough strength. Pressing properties, easy care properties, and shrinkproof properties can be imparted, and in the case of sewn products, sufficient form stability, puckering properties, and pleating properties can be imparted.

Claims (1)

(57) [Claim 1] A water-soluble urethane prepolymer and a formaldehyde having a thermally dissociable block isocyanate group at the end and an alkylene oxide group at the main chain on a fabric containing cellulosic fibers. After providing a compound having a free nitrogen group capable of reacting with the above, heat treatment is performed at a temperature equal to or higher than the thermal dissociation temperature of the thermal dissociation type blocked isocyanate group to polymerize the water-soluble polyurethane prepolymer. Then, the moisture content of the fabric is adjusted to 1 to 5
A method for processing a cellulosic fiber cloth, which comprises uniformly adjusting the concentration to 0%, and then subjecting the cloth to formaldehyde gas adsorption, heat treatment, and cross-linking by formaldehyde.