JPS6114194B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a neutralizing agent for alkaline gelatinized starch paste. In warp gelatinization, which is carried out as a preparation process for weaving, and especially for spun yarns, natural materials such as cornstarch and wheat starch are generally used to maintain the fluffing effect and to maintain fiber strength and elongation that can withstand repeated impacts and friction, as well as tension during weaving. A glue is used. However, such starch glue is generally difficult to handle due to its high viscosity at low temperatures, so it was
As described in Japanese Patent No. 57081, a gelatinized starch paste is used which is obtained by gelatinizing with an alkali hydroxide and then neutralizing with an acid. The gelatinized starch paste obtained in this way does not have sufficient abrasion resistance due to the lack of tensile strength and flexibility of the dried film, and in reality, the gelatinized starch paste obtained cannot be used in various ways. The reality is that these additives are included. Further, although this glue has the advantage of being able to be glued even at low temperatures (room temperature), it does not have sufficient storage stability. When neutralizing alkali-gelatinized starch, the present inventors used an ethylenically unsaturated carboxylic acid monopolymer or copolymer instead of the conventional inorganic acid or lower carboxylic acid. It was discovered that the above-mentioned drawbacks could be overcome, and that the properties of the adhesive itself were also improved, leading to the completion of the present invention. That is, the present invention provides an alkaline gelatinized starch paste for warp-sizing containing an unneutralized monopolymer or copolymer of an ethylenically unsaturated monocarboxylic acid or a salt thereof with a heat-volatile organic base. Regarding Japanese preparations. Examples of ethylenically unsaturated monocarboxylic acids used in the present invention include acrylic acid, methacrylic acid, crotonic acid, itaconic acid, and styrene carboxylic acid. Preferred are acrylic acid, methacrylic acid, and the like. The above-mentioned polymer of ethylenically unsaturated monocarboxylic acid is produced by a general polymerization method. For example, acrylic acid may be polymerized in an aqueous solution using an initiator such as ammonium persulfate. A copolymer of the above ethylenically unsaturated monocarboxylic acid and another monomer may be used as the neutralizing agent of the present invention. Examples of monomers copolymerizable with the above acids include ethylenically unsaturated esters, such as methyl methacrylate, ethyl methacrylate,
Methyl acrylate, ethyl acrylate; polymerizable alkene monomers such as ethylene, propylene, butylene, pentene, hexene, heptene, styrene and its alkyl-substituted styrenes;
Ethylenically unsaturated nitriles such as acrylonitrile; ethylenically unsaturated amides such as acrylamide and methacrylamide; β-hydroxyalkyl methacrylate, etc.; unsaturated carboxylic acids such as maleic acid, methylmaleic acid, fumaric acid, etc.; vinyl acetate, etc. be done. The alkyl portion other than the carboxyl group of the monomer copolymerizable with the ethylenically unsaturated monocarboxylic acid has 3 to 20 carbon atoms, preferably 3 to 10 carbon atoms. When the number of carbon atoms exceeds 20, the effect of modifying the properties of the size liquid is hardly recognized. The above copolymers are produced by conventional methods. For example, the emulsifier and the monomer may be mixed and then polymerized using a suitable polymerization initiator. The amount of ethylenically unsaturated monocarboxylic acid monomer in the above copolymer is 5% by weight or more, preferably 50% by weight or more of the total amount of monomers. If it is less than 5% by weight, it will be difficult to remove the size after weaving. Furthermore, the lower the acid content, the less effective it is as a neutralizing agent, so it is not necessary to add a large amount, which makes it uneconomical. Furthermore, the gelling prevention effect and the modifying effect on size liquid properties are also reduced. The polymer may be a heat-volatile organic salt, such as an ammonium salt or an amine salt. The volatile salt mentioned above is volatilized during the gluing and drying process,
Acts similarly to unneutralized carboxyl group-containing polymers. The neutralizing agent for the alkali gelatinized starch paste of the present invention is preferably added in an amount equivalent to neutralizing the alkali hydroxide used when gelatinizing the starch. Of course, it may be used in combination with a conventionally used neutralizing agent (for example, sulfuric acid, etc.). As examples of the starch paste used in the present invention, natural pastes such as corn starch and wheat starch are generally used. After adding these starches to water, they are gelatinized with an alkali such as an alkali hydroxide. Alkaline gelatinization is usually carried out at a low temperature of room temperature to 40°C. The neutralizing agent of the present invention is used to neutralize the alkali-gelatinized starch paste. The neutralized starch paste is used as a sizing agent after dilution. The resulting sizing agent is sized by conventional methods. Other usual modifying agents such as polyvinyl alcohol, carboxymethyl cellulose, acrylic thickening agent, combined oil agent, etc. are added to the sizing liquid obtained by adding the neutralizing agent of the present invention, and it is used as a sizing agent. It's okay. The alkaline gelatinized starch paste neutralized using the neutralizing agent of the present invention has increased elongation and abrasion resistance strength of the sizing yarn, and has improved weaving properties, compared to those neutralized with conventional inorganic or organic acids. will improve. Furthermore, salts produced by conventionally used neutralizing agents such as acids have an adverse effect on the physical properties of the glue, but the neutralizing agent according to the present invention has almost no such adverse effect on the physical properties. Furthermore, when the neutralizing agent of the present invention is used, the stabilizing effect on the viscosity of the paste liquid is greatly improved. For example, according to the conventional neutralization method, the produced glue has thixotropic properties and becomes gel-like when left alone, but when the neutralizing agent of the present invention is added, the thixotropic properties are almost eliminated. , it is possible to maintain a fluid liquid state even if left to stand naturally. Therefore, compared to the conventional method in which the produced glue cannot be transported through a pipe unless it is constantly stirred, the process can be streamlined and simplified because it can be stored stationary. Furthermore, starch paste made with conventional neutralizing agents requires high temperatures,
For example, the viscosity changes significantly at temperatures above 60℃,
Although it has been difficult to control the amount of glue deposited, the neutralizing agent of the present invention has the characteristic that the change in viscosity at temperatures of 60° C. or higher is extremely small and temperature control is easy. The present invention will be explained in more detail with reference to Examples.
Percentages in the examples are by weight unless otherwise indicated. Examples 1 and 2, Comparative Example 1 Preparation of Neutralizing Agent A: 250 g of soft water was charged into a four-necked round-bottomed flask equipped with a reflux condenser, dropping funnel, thermometer, and stirrer, and oxygen was removed by passing nitrogen gas. While stirring, the temperature was raised to 80°C. 150 g of acrylic acid was diluted with 340 g of soft water and charged into a dropping funnel. 0.3 g of ammonium persulfate was added to the flask and dropwise polymerization was immediately initiated. The polymerization temperature was maintained at 80°C, and the dropwise addition was completed in 1 hour. After completion of the dropwise addition, 0.05 g of ammonium persulfate was diluted with 2 g of soft water and added into the flask, and after polymerization at 80° C. for 1 hour, 0.05 g of ammonium persulfate was further diluted with 2 g of soft water and added. After the addition, the temperature was raised to 85° C. and polymerized for 1 hour to obtain polyacrylic acid (this is referred to as neutralizing agent A). Preparation of neutralizing agent B: Using the same equipment as in the example, add soft water to a flask.
200g, acrylic acid 126g, methacrylic acid 84g, methyl methacrylate 30g, ethyl acrylate 20g, vinyl acetate 30g, acrylic acid-2-
To 6 g of ethylhexyl and 4 g of acrylonitrile monomers, 2.0 g of sodium lauryl sulfate, 1.5 g of potassium persulfate, 0.6 g of lauryl mercaptan, and 200 g of soft water were added and mixed with stirring. Stirring was continued to maintain the monomer in an emulsified and dispersed state until the dropwise addition was completed. Soft water stirred and heated in a flask is 85
When the temperature reached ℃, 50g of the monomer emulsion was instantly added from the dropping funnel, prepolymerized for 5 minutes, and then the remaining amount of the monomer emulsion was added over 1 hour while controlling the temperature at 85℃. Polymerization was carried out by dropping.
After the dropwise addition was completed, 0.05 g of potassium persulfate dissolved in 2 g of soft water was added and polymerized at 85° C. for 1.5 hours. Thereafter, it was cooled to 40°C, and 37 g of 25% aqueous ammonia was added dropwise to neutralize it (this was referred to as neutralizing agent B). Preparation of cornstarch alkaline gelatinization paste: 400g of water and 100g of cornstarch were placed in a kneading tank and mixed with stirring to form a dispersion. Next, 7.2 g of sodium hydroxide was dissolved in 50 g of water and then added to the above dispersion. After 10 minutes of kneading, 50 g of water was added.
Thereafter, the mixture is kneaded and stirred for 40 minutes to perform alkaline gelatinization. Thereafter, the pH was adjusted to 8.0 to 8.5 using the acid (sulfuric acid) described in Japanese Patent Publication No. 57-57081 or the neutralizing agents A and B as neutralizing agents. Adjustment of size liquid: The size liquid was adjusted as shown in Table-1. Table 1 shows the pure content ratio (%) and size concentration (%) of the obtained size liquid.
Describe it in

[Table] Test example 1 Using the above adhesive, using a sizing machine combined with a hot air cylinder, the gluing temperature was 50℃,
Glue was applied to 4,320 yarn-dyed cotton yarns, number 40, using a winding method (PIV method) at a speed of 70 m/min. After-waxing was mainly made of paraffin wax, and the machine set the amount of oil deposited to 0.2%.
The fabric specifications were a number 40 single yarn in the warp and a single yarn number 16 in the weft, and the density was 96 yarns/inch for the warp and 50 yarns/inch for the weft. The fabric was obtained using a shuttle loom (165 rpm). Table 2 shows the results of the physical properties and weaving efficiency of the sized yarn.

[Table] Example 3 In this example, changes in viscosity due to temperature changes were measured between the sizing agent obtained according to the present invention and a conventional sizing agent. Measurements are made using a Brabender amylograph.
This shows the changes in viscosity of a glue solution with a concentration of 10%. The amount of sodium hydroxide added during gelatinization is the same in both cases. The results are shown in Figure 1. When the size liquid 1 obtained by neutralization with sulfuric acid is heated, the viscosity increases from the point at which the temperature exceeds 60°C. In comparison, the size liquid 2 using the neutralizing agent of the present invention shows less change in viscosity, and the viscosity itself shows a lower value. In addition, if the glue solution 1 is allowed to stand at room temperature, it becomes gel-like, but
Size liquid 2 maintained its fluidity even after 24 hours.

[Brief explanation of the drawing]

FIG. 1 is an amylograph showing changes in viscosity depending on temperature of a sizing agent 1 neutralized with the neutralizing agent of the present invention and a sizing agent 2 neutralized with a conventional neutralizing agent (sulfuric acid).

Claims (1)

[Scope of Claims] 1. Alkaline gelatinized starch glue for warp sizing containing a co-neutralized product of a homopolymer or copolymer of ethylenically unsaturated monocarboxylic acid or a salt thereof with a heat-volatile organic base neutralizing agent. 2. The neutralizing agent according to item 1, wherein the ethylenically unsaturated monocarboxylic acid is acrylic acid or methacrylic acid. 3. The monomer copolymerizable with ethylenically unsaturated carboxylic acid is an ethylenically unsaturated ester, an ethylenically unsaturated amide, an ethylenically unsaturated nitrile,
2. The neutralizing agent according to item 1, which is a polymerizable alkene monomer, an unsaturated polycarboxylic acid, or vinyl acetate. 4. The neutralizing agent according to item 1, wherein the copolymer contains 5% by weight or more of ethylenically unsaturated monocarboxylic acid. 5. The neutralizing agent according to item 1, wherein the copolymer contains 50% by weight or more of ethylenically unsaturated monocarboxylic acid. 6. The neutralizing agent according to item 1, wherein the organic base is an amine or ammonia.