JPS6160199B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for processing a fiber fabric in which a reactive urethane composition is applied to the fabric and a transparent effect is created by preventing diffused reflection in the applied area.

Conventionally, methods for producing a transparent effect on fabric include an organdy processing method using sulfuric acid, an opal processing method, and a processing method that imparts a chemical that makes the film transparent.

The organdy processing method using sulfuric acid is a method in which a cellulose-based fabric is passed through a sulfuric acid bath to form parchment and give a transparent effect.If you want to express a transparent effect as a pattern, it is necessary to apply acid-resistant dye resist paste in advance. Use fabric with a pattern printed on it. However, this organdy processing method has a very rapid reaction, which makes stable processing difficult, and hardening and brittleness occur as a result of parchment formation, which limits its applications. Furthermore, there is a problem that only cellulose fibers such as cotton and rayon can be used as fabrics.

The opal processing method mainly uses cellulose fibers such as cotton and rayon, polyester, nylon,
This is a method in which a blended product with acid-resistant fibers such as silk is printed with a printing paste containing sulfuric acid or aluminum sulfate, etc., and the cellulose fibers in the printed area are carbonized and removed by heat treatment to reveal a transparent pattern. but,
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This method can only be applied to the above-mentioned blended fabrics, and it is inevitable that the strength of the transparent portion from which the cellulose fibers have been removed will decrease and the shearing phenomenon will occur. Furthermore, since a strong carbonization reaction is required, the remaining acid-resistant fibers are affected, and sufficient management is required.

The processing method of imparting chemicals that make the film transparent is generally a method of imparting an emulsion of aliphatic hydrocarbons, acrylic esters, methacrylic esters, etc. to the fibers to prevent diffused reflection of the fibers and impart a transparent effect. . These have the advantage of being extremely simple to process, but on the other hand, they have the disadvantage of poor transparency. Also,
Since aliphatic hydrocarbon emulsions cannot be sufficiently fixed onto fibers, their washing durability is extremely low. Acrylic ester or methacrylic ester emulsions have slightly better washing durability than aliphatic hydrocarbon emulsions, but they also have problems in terms of texture. For example, methyl acrylate,
Ethyl acrylate, methyl methacrylate, and ethyl methacrylate give too hard a texture, and butyl acrylate and butyl methacrylate have too strong stickiness. Therefore, all of these have low quality value.

In view of these circumstances, the inventors of the present invention have conducted intensive research and found that the material to be used is not limited, the application method is extremely simple, and transparency is achieved without hardening or stickiness of the texture or loss of strength. We have also discovered a transparent processing method that can produce fiber fabrics with excellent durability.

The present invention relates to a urethane prepolymer having a molecular weight of 1,000 to 10,000 and containing 1.0 to 10% by weight of free isocyanate groups.
95% by weight is blocked with a blocking agent that does not provide water solubility or water dispersibility, and the remaining free isocyanate groups contain one or more active hydrogen atoms and anionic salt-like groups or anionic salt-forming groups within the same molecule. using a water-soluble or water-dispersible reactive urethane composition blocked with a compound having When applying to fabric, the resin content is calculated based on the fiber weight of the applied area.
This is a transparent processing method for a fiber fabric, which is characterized by imparting an owf of 10 to 90% and then heat-treating the fabric.

The present invention will be explained in detail below. Used in the synthesis of the reactive urethane composition used in the present invention
The urethane prepolymer containing 1.0 to 10% by weight of isocyanate groups has 2 active hydrogen atoms.
Examples include those obtained from a compound having a molecular weight of 800 to 8,000 or more, an excess amount of polyisocyanate, and, if necessary, a chain extender. Examples of compounds having two or more active hydrogen atoms include those containing two or more hydroxyl groups, amino groups, or mercapto groups at the end or in the molecule, and particularly preferred are polyethers, polyesters, and polyether esters. It takes a form.

Examples of the polyether include alkylene oxides, styrene oxide, polymerization products such as epichlorohydrin, and addition polymers of polyhydric alcohols. Polyesters and polyether esters include polyvalent saturated and unsaturated carboxylic acids or their acid anhydrides, polyvalent saturated and unsaturated alcohols, relatively low molecular weight polyalkylene ether glycols, and mixtures thereof. Examples include linear or branched condensates obtained. Also included are polyesters made from lactones and hydroxy acids, and polyetheresters obtained by adding alkylene oxides to pre-produced polyesters.

As for polyisocyanate, since this processing method targets fabric, it is necessary to consider non-yellowing.
Preferred are aromatic aliphatic isocyanates such as xylylene diisocyanate, alicyclic diisocyanates such as isophorone diisocyanate, and aliphatic isocyanates such as hexamethylene diisocyanate. However, if non-yellowing is not considered, it is not limited to these.

As the chain extender, glycols, polyhydric alcohols, diamines, amino alcohols, diglycols, water, etc. can be used. In this case, the molar ratio of isocyanate groups/active hydrogen groups can be freely selected from 1 or more, but the content of free isocyanate groups in the resulting urethane prepolymer must be 1.0 to 10% by weight, preferably 7% by weight or less. shall be. Note that this urethane prepolymer synthesis reaction is usually carried out without a solvent, but the resulting urethane
Depending on the prepolymer, a solvent may be added first in view of viscosity and in consideration of workability in subsequent steps. Examples of the solvent include solvents that are inert to isocyanate groups and can dissolve the urethane prepolymer, and hydrophilic solvents are particularly preferred.

Next, for the urethane prepolymer obtained by the above method, a blocking agent that does not provide water solubility or water dispersibility for blocking 50 to 95% by weight of free isocyanate groups is particularly recommended at temperatures above room temperature and 100% by weight. It is preferable to use a material that can react with the urethane prepolymer at temperatures below 0.degree. C. to form a blocking agent. Examples of such substances include secondary to tertiary alcohols, active methylene compounds, phenols, halogenated phenols, oximes, lactams, etc. The reaction between these and urethane prepolymers is carried out using a urethanization catalyst as is known. Alternatively, it is carried out in the presence of an alkali metal alcoholate catalyst or without a catalyst.

Next, examples of compounds having one or more active hydrogen atoms and an anionic salt-like group or an anionic salt-forming group in the same molecule for blocking the remaining free isocyanate groups include aminosulfonic acids and aminocarboxylic acids. and those having two types of groups: an amino group or a hydroxyl group and a sulfonic acid group or a carboxylic acid group. These are used as lithium salts, sodium salts, potassium salts, ammonium salts, etc. to make them water-soluble. Therefore, when reacting these with essentially water-insoluble partially blocked urethane prepolymers, suitable hydrophilic solvents are required to improve their miscibility. Although this does not apply to those to which a hydrophilic solvent has already been added at the prepolymerization stage, it is also possible to use solvents such as alcohols that cannot be used at the prepolymerization stage. It is. This is because this blocking reaction proceeds very rapidly at low temperatures, so that the reaction between alcohols and free isocyanate groups can be substantially ignored.

In addition, for a water-soluble reactive urethane composition in which all of the free isocyanate groups are blocked with bisulfite, the molecular weight containing 1.0 to 10% by weight of the above free isocyanate groups is 1000 to 1000.
10,000 urethane prepolymers containing 10 to 40% by weight of oxyethylene chains are directly blocked with a bisulfite aqueous solution without being blocked with a blocking agent that does not provide water solubility or water dispersibility. Any compound synthesized by a conventionally known method can be used.

The urethane composition synthesized as described above is
Depending on the type of urethane prepolymer used, the phase of the water-in-oil emulsion changes to an oil-in-water emulsion after the blocking starts, or the oil-based emulsion is maintained during blocking and then enters the water dilution stage. In some cases, there is a phase inversion from an oil-in-water emulsion, but in both cases, the final result is a stable water-soluble or water-dispersible reactive urethane composition in which free isocyanate groups are blocked. This reactive urethane composition can be stored for a long time, and by heat treatment at 100 to 180°C, the blocking agent dissociates and the isocyanate groups are regenerated, and the isocyanate groups subsequently react and become polymerized. Compared to conventional water-based urethanes, this urethane has superior durability, strength and elongation, and is also non-adhesive.

Therefore, in the present invention, a water-soluble or water-dispersible reactive urethane resin composition synthesized by the above method is applied to a fiber fabric, and then heat-treated to polymerize the fiber on the fiber. It serves the purpose of imparting transparency to the fabric and its durability. As a device for applying the reactive urethane composition to the fiber fabric, a rotary screen printing machine, a flat screen printing machine, a roller type printing machine, etc. are preferable, but a device for applying a high viscosity liquid such as a coating machine can also be used. , These allow the transparent effect to be expressed as a desired transparent pattern on the fiber or as full transparency. The amount of reactive urethane composition applied is 10 to 90% of the fiber weight of the applied part.
owf is preferred; if it is less than 10% owf, the transparency effect will be poor, and if it exceeds 90% owf, the change in texture will be too large. Furthermore, since this reactive urethane resin is a viscous liquid, it can be easily adjusted to a viscosity suitable for the application device by diluting it with water, and no thickener is particularly required.

As described above, the present invention has extremely simple workability compared to the organdy processing method and the opal processing method, does not involve hardening of the texture or decrease in strength of the transparent part, and is not limited to the materials to which it can be applied. 〓〓〓〓
In addition, when compared to the conventional method using a transparent agent, there is no hardening or stickiness of the texture of the transparent part, and the most important feature of the method of the present invention is transparency and its durability. It has advantages such as superior properties. It is not clear why a product with excellent transparency and durability can be obtained, but the transparency and durability of polymerized urethane obtained by reacting a reactive urethane composition through heat treatment are good. In addition to this, it is presumed that this is due to the fact that this reactive urethane composition has high permeability. In other words, this reactive urethane composition has a relatively low molecular weight compared to general emulsion resins, and the composition itself has a structure similar to that of a polymeric surfactant, making it difficult to penetrate into fibers. It has very good properties and can easily penetrate into the fiber structure and fully fill the voids in the fibers, which increases the effect of preventing diffused reflection of the fibers, resulting in increased transparency and the ability to interact with the fibers. It is thought that the adhesiveness becomes better due to the filling effect and the durability also increases.

Next, examples of the method of the present invention will be described, but the present invention is not limited thereto.

Example 1 37.6 parts of xylylene diisocyanate was added to 200 parts of a polyether polyol (molecular weight 3000) of a polyadduct of glycerin base, ethylene oxide, and propylene oxide (ethylene oxide: propylene oxide = 50:50) at room temperature to form a system. The reaction was carried out for 70 minutes at an internal temperature of 95°C to obtain a urethane prepolymer (theoretical molecular weight: 3564) containing 3.57% by weight of free isocyanate. Next, 14.5 parts of ε-caprolactam dissolved in 71.3 parts of dioxane was added, and the reaction was carried out at an internal temperature of 95° C. for 6 hours to obtain a partially blocked urethane prepolymer containing 1.30% by weight of free isocyanate. Next, after setting the system temperature to 40°C, 26.6 parts of a 40% taurine soda aqueous solution was added, and the reaction was carried out at the same temperature for 30 minutes.
Add 11.7 parts of a 20% IPA solution of Nokrac NS-7 (manufactured by Ouchi Shinko Chemical Industry Co., Ltd., monophenolic antioxidant), and finally dilute with water to create a transparent viscous heat-reactive water-soluble resin with a resin content of 35%. A urethane resin composition was obtained.

Elastron Catalyst 32 (manufactured by Daiichi Kogyo Seiyaku, an organotin catalyst) was added to 100 parts of this urethane composition.
Mix 15 parts and add an appropriate amount of sodium hydrogen carbonate to adjust the pH to 7.5. Further increase the viscosity with water.
It was adjusted to 8000c.ps as a printing paste.

The above printing paste was printed in a floral pattern on a cotton lawn cloth using a flat screen printing machine, then dried and then heat treated at 160°C for 2 minutes.

The fabric thus obtained had excellent transparency in the printed area. This fabric is JIS L-
When washed 20 times using the washing method specified in Law 0217103, the transparency effect did not deteriorate at all and the product had good durability.

Example 2 To 36 parts of polyester diol (OH.V = 111.8) obtained from adipic acid, 1,6-hexadiol, neopentyl glycol (molar ratio 4:3:2) and 41 parts of polyethylene glycol with a molecular weight of 1000,
23 parts of xylylene diisocyanate was added at room temperature, and the reaction was carried out for 60 minutes at a system temperature of 95°C to obtain a urethane prepolymer containing 3.86% by weight of free isocyanate. Cool this to 40℃ and
After adding 50 parts of % potassium bisulfite aqueous solution and continuing stirring for about 20 minutes, it was finally diluted with water to reduce the resin content to 35%.
% of a transparent viscous heat-reactive water-soluble urethane resin composition was obtained.

5 parts of Elastron Catalyst 32 was mixed with 100 parts of this urethane composition, and the viscosity was further increased with water.
The printing paste was adjusted to 8000 c.ps, and printing was performed on cotton lawn under the same conditions as in Example 1.

The fabric thus obtained had good transparency and durability as in Example 1.

Example 3 95 parts of hexamethylene diisocyanate was added to 200 parts of polyester diol (OH.V=90) obtained from adipic acid and 1,6-hexadiol, 60 parts of polyethylene glycol with a molecular weight of 1000, and 10 parts of trimethylolpropane at room temperature. was added, the system temperature was raised to 90°C, and the reaction was carried out for 60 minutes to obtain a urethane prepolymer (theoretical molecular weight: 1837) containing 5.20% by weight of free isocyanate. Next, 47 parts of ethyl acetoacetate, 100 parts of dioxane, and sodium methylate.
1.0 part was added and the reaction was carried out at 80°C for 2 hours to obtain a partially blocked urethane prepolymer containing 1.0% by weight of free isocyanate. Next, after setting the temperature in the system to 40℃, 28 parts of 30% glycine soda aqueous solution was added and reacted for 40 minutes at the same temperature.
A transparent and viscous heat-reactive water-soluble urethane resin composition with a resin content of 40% was obtained.

This urethane composition was prepared as a printing paste in the same manner as in Example 1, and printed on a polyester lawn cloth in a polka dot pattern using a flat screen printing machine, dried, and then heat-treated at 150° C. for 3 minutes.

The fabric thus obtained had excellent transparency in the printed area, and its durability was also as good as in Example 1.

Example 4 Urethane prepolymer 200 used in Example 2
A mixture of 17.9 parts of phenol dissolved in 60 parts of dioxane is added to the solution, followed by addition of triethylamine.
0.4 part was added, the temperature in the system was raised to 70°C, and the reaction was carried out for 60 minutes to obtain a partially blocked urethane prepolymer containing 1.20% by weight of free isocyanate. Next, after raising the temperature to 40℃, 21 parts of a 40% taurine soda aqueous solution was added and the reaction was carried out at the same temperature for 30 minutes.Finally, it was diluted with water to form a transparent viscous heat-reactive type with a resin content of 40%. A water-soluble urethane resin composition was obtained.

15 parts of Elastron Catalyst 32 are mixed with 100 parts of this urethane composition, and sodium hydrogen carbonate is further added to adjust the pH to 7.5. Finally, the viscosity was adjusted to 5000 c.ps with water and used as a printing paste.

The above printing paste is printed on nylon taffeta in a striped pattern using a rotary screen printing machine.
It was then dried and then heat treated at 170°C for 1 minute.

The fabric thus obtained had excellent transparency in the printed area. Moreover, the washing durability was also good.

Example 5 The transparent printed cloth obtained by the method of Example 1 was dyed with Kayara Light Red F5B (Nippon Kayaku, direct dye).
Staining was carried out at 90°C for 30 minutes at a bath ratio of 1:30 with 0.7% owf, followed by washing and drying in the usual manner.

Only the unprinted remaining portion of the obtained fabric was dyed pink, and the printed portion appeared to be colorless and transparent, resulting in a fabric rich in variation.

Example 6 The transparent printed fabric obtained by the method of Example 1 was dyed with Miketone Polyester Blue-FBL (disperse dye manufactured by Mitsui Toatsu Chemical Co., Ltd.) 0.5% owf at 95°C at a bath ratio of 1:30.
Staining was carried out for a minute, followed by washing and drying.

The resulting fabric was dyed blue only in the printed area, resulting in a fabric rich in variation in which the blue transparent pattern appeared to stand out from the undyed remaining area.

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Claims (1)

[Claims] 1 50 to 95% by weight of free isocyanate groups in a urethane prepolymer with a molecular weight of 1,000 to 10,000 containing 1.0 to 10% by weight of free isocyanate groups
is blocked with a blocking agent that does not provide water solubility or water dispersibility, and the remaining free isocyanate group has one or more active hydrogen filaments and an anionic salt-like group or an anionic salt-forming group in the same molecule. A water-soluble or water-dispersible reactive urethane composition blocked with a compound, or a water-soluble reactive urethane composition in which all free isocyanate groups are blocked with a bisulfite salt, is used to impart to the fabric. 10 to 90% owf as pure resin based on the fiber weight of the applied part.
1. A method for transparently processing a fiber fabric, which comprises applying the transparent coating to the fabric, and then heat-treating the fabric.