JPS59157377A - Treatment of fiber struction - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for treating a fibrous structure containing polyester fibers.

Conventionally, it is well known that polyester fiber structures are treated with alkali to reduce their weight, thereby obtaining a soft feel. In addition, even if the same polyester is used, after mixing the yarn 1 (which is easily dissolved by alkali treatment) with fibers which are difficult to dissolve by blending, blending, etc., it is possible to make a fiber structure by mixing all the fibers that are easily dissolved by alkali treatment. A method of dissolving and removing the fibers is also known.A further development of these methods involves alkali treatment of composite fibers, which consist of components that are easily treated with alkali and components that are difficult to be treated with alkali, to completely remove the components that are easily treated with alkali. It is also known that ultra-fine fibers or fibers with special shapes can be obtained.However, in either case, it takes a long time to completely dissolve and remove the fibers that are easily treated with alkali, and the fibers that are difficult to dissolve are difficult to dissolve. Alkali weight loss was achieved by mt.

Not only does strength decrease, but stable quality such as texture and touch cannot be obtained. For this reason, it has been considered to use a highly concentrated alkali or to raise the temperature for a short treatment time, but these also help to reduce the amount of components that are difficult to dissolve.

The disadvantage is that the cost is very high. In particular, in the method of obtaining ultrafine fibers using composite fibers, if the above method is applied, in extreme cases, the ultrafine fibers will be dissolved and cut, and the value as a fiber structure will be lost, and the quality will still be stable. The current situation is that these products have not been put into practical use.

The present inventors conducted extensive research to solve the above-mentioned drawbacks, and as a result, they discovered a method that allows selective alkali reduction of only the extracted and eluted polyester within a short period of time.

JP-A No. 56-118961 proposed pre-treatment using a polyester embrittling agent. but.

Even with this method, if the fibers that are difficult to elute are polyester, it is difficult to completely protect the fibers that are difficult to elute, although there is a difference in elution rate.

This caused the problem of reduced strength, and from a practical point of view, there was a desire for improvement.

As a result of examining the amount of lead regarding such improvement measures, pre-trial f111
The present invention was achieved based on the discovery that by selecting specific conditions in the alkali treatment step, only the components to be eluted can be dissolved and removed very effectively.

That is, 1 the present invention provides a fiber yarn 1 (structure) comprising two or more components, at least one of which is a polyester, which is treated with an embrittling agent for the polyester and then treated with an alkali, the alkali treatment temperature is The present invention relates to a method for treating a fibrous structure, characterized in that the temperature is 95°C or less.

Normally, when fibers are subjected to weight loss treatment with alkali, they are generally treated in a boiling aqueous solution for a long time, so even polyesters that are difficult to dissolve in alkali cannot avoid considerable weight loss. For this reason, not only the strength decreases but also stable quality cannot be obtained. Based on these facts, the present inventors have found that by optimizing the treatment conditions in the combination of the above-mentioned embrittling agent treatment and alkali treatment, it is possible to economically and quickly obtain a weight-reduced product of stable quality. It is something that

Hereinafter, one aspect of the present invention will be explained in detail.

The fiber structure in the present invention includes yarn, cotton, and tow.

It refers to all forms of fibers or processed products thereof, such as tops, woven fabrics, nonwoven fabrics, etc., and is not particularly limited to these.

In the present invention. At least one component is polyester. What is a fiber structure containing two or more components?1
For example, two or more components are spun separately and then mixed by means such as blending or blending, or so-called Myogosou fibers, such as fibers made of multiple components as shown in Figures 1 to 9, are used. Examples include, but are not limited to, fibers, etc. In short, at least one component is polyester.

This is a component that can be removed by alkali treatment, and there are no particular restrictions on how the component is included as long as the fiber structure contains one or more other components.

In the case of FIGS. 1 to 9, the A component (margin area) is the component that is removed by the alkali metal. In general, in the case of sea-island composite fibers, the sea component is the component that is removed by the alkali. The polyester components removed by the alkali treatment include polyethylene terephthalate, polybutylene terephthalate, and various modified polymers thereof, but among them, dicarboxylic acids, diols, or oxycarboxylic acids containing alkali metal sulfonates, or multiple thereof, etc. Polymerized ones, or blends or composites of those copolymers/C ones are better;
Particularly preferred is sodium sulfoisophthalate, particularly sodium 5-sulfoisophthalate. Of course, an ester-forming rust conductor may also be used. still,
Those having one hydroxyl group and one carboxyl group in the molecule, such as sulfonate of methyl oxyethoxybenzoate, can also be used. The content of alkali metal sulfonate groups is preferably 0005 to 0.50 gram equivalent/chaos fiber. In addition to synthetic fibers such as polyesters, polyamides, polyacrylics, etc., the one or more other components that are degraded by alkali at a slower or more difficult rate than the polyester component are removed by alkaline treatment.

Examples include semi-synthetic fibers such as acetate, recycled fibers such as rayon (1" fibers), and natural fibers such as cotton, but in the case of 9% polyester, the effect of the method of the present invention is remarkable.

The polyester embrittlement agent used in the present invention is a substance that lowers the average molecular weight of polyester, and includes, for example, ethylenediamine and ethylenetriamine.

Amines such as monoethanolamine, zinc chloride.

Subsalt salts such as zinc sulfate and zinc nitrate, hydrogen peroxide.

Oxidizing agents such as sodium hypochlorite and sodium chlorite.

Inorganic acids such as hydrochloric acid + L acid, nitric acid, phosphoric acid, and boric acid.

Examples include organic acids such as acetic acid, oxalic acid, maleic acid, benzoic acid, and fucuric acid, among others, acids.

Especially when considering workability, *machine damage, drainage, etc., carboxylic acids having a hydrocarbon group are preferred.

In the embrittling agent treatment referred to in the present invention, the embrittling agent is concentrated (1%
(2) For example, when treating a fibrous structure with an aqueous solution in a boiling aqueous solution using an organic acid such as acetic acid, a dilute solution requires a considerably long treatment time. On the other hand, if a concentrated solution is used, the cost is very high, and if an inorganic acid such as sulfuric acid is used, mechanical damage is likely to occur even if the solution is diluted.

The present inventors have discovered that this problem can be completely solved by treating with an embrittlement agent at a low concentration and in a short period of time.

That is, in a preferred embodiment of the present invention, the concentration of the embrittlement agent is less than 1%, preferably in the range of 0.05 to 0.05%, more preferably in the range of 0.01 to 0.03, and the treatment temperature is The treatment is carried out at a temperature of 100 DEG C. or higher, preferably 110 DEG to 10 DEG C., for a short time of 5 to 60 minutes. Still in the treatment bath is the carrier.

The inclusion of a surfactant such as a quaternary ammonium salt may provide better results.

The alkaline treatment in the present invention refers to a treatment in which polyester is hydrolyzed with an alkaline substance, and generally, alkaline substances 2 such as alkali metal hydroxides, alkali metal sulfides, and alkali metal sulfites are used. salts, alkali metal phosphates, alkali metal silicates and alkali metal carbonates. The alkaline solution can be prepared by using one kind or a combination of two or more kinds selected from the above-mentioned compounds. As a treatment method, it is preferable to selectively elute only the dissolved components as much as possible in an aqueous solution containing the alkaline substance at a temperature of 95° C. or lower, preferably 80° C. or lower, for 30 to 90 minutes.

At temperatures above 95°C, the dissolution rate is too fast, making it difficult to control the weight loss of fibers that are difficult to dissolve, and unavoidable decreases in texture and strength.

This will be explained in more detail in Examples below.

Example 1 Both warp and weft yarns are 112 denier/2 with sea-island type composite weave.
It was woven into a taffeta structure using 8 filament yarn. The specifications of the yarn used are as follows.

Sea component: polyethylene terephthalate copolymerized with 4 mol% of 5-sodium sulfoinphthalic acid High acid: 0: polyethylene terephthalate Weight ratio of sea component and island component +20780 The fabric is 0.1
In an aqueous solution containing % maleic acid.

After processing for 30 minutes at 120'c-c, it was processed at 80°C for 45 minutes in an aqueous solution containing sodium hydroxide.

As Comparative Example 1, the fabric of Example 1 was used, and after being treated in the same manner as in Example 1 in an aqueous solution containing maleic acid of Section 01,
It was treated for 45 minutes in a boiling aqueous solution containing Caustic Noda 1.

The treated fabric was dyed under the following conditions, the reflectance of the dyed fabric was determined, and the residual sea component was investigated.

Diacryl Br111. Red 6B-N
O, 2% (owf) pH 4,0 80'c x 45 minutes The results are shown in the table below.2 The method of the present invention can selectively remove sea components dissolved by alkali, and also reduces the strength of the treated fabric. A product with a soft texture was obtained.

(Note) 1. Reflectance was measured with a Macbeth spectrophotometer. The larger the number, the better.

2 Tear strength was measured using an Elenandorff tear strength tester.

Example 2 The fabric of Example 1 was treated in an aqueous solution containing 1% maleic acid at 0°C for 5 minutes, and then in an aqueous solution containing 1% caustic soda at 80°C for 45 minutes.

As Comparative Example 2, the sample was treated in a boiling aqueous solution containing 1% maleic acid for 60 minutes, and then treated with alkali under the same conditions as Example 2.

The treated fabric was evaluated in the same manner as in Example 1.

The results are shown in the table below in both cases.

The sea component can be completely removed by the method of the present invention-1.
It can be seen that this is an economical method that can significantly reduce and shorten the chemical concentration and processing time.

Example O: The warp yarn is a 75 denier, 72 filament polyester yarn, and the weft yarn is 112 denier.

A 28-filament sea-island composite fiber was used to weave a taffeta structure. The specifications of the sea-island composite fiber used are the same as in Example 1.

The fabric was placed in an aqueous solution containing 0.1% maleic acid.

After being treated with 13D'a for 15 minutes, it was treated in an aqueous solution containing sodium hydroxide at 80°C for 45 minutes.

As Comparative Example 6, the same fabric was treated in a 1% aqueous acetic acid solution at 130'O for 30 minutes, and then in a boiling 1% caustic soda aqueous solution for 60 minutes.

The treated fabric was evaluated in the same manner as in Example 1.

The results are shown in the table below.The method of the present invention can quickly and selectively remove only the sea component of the weft yarn.

It can be seen that in the case of Comparative Example 6, even the warp threads were reduced in weight and only a product with low strength was obtained.

[Brief explanation of the drawing]

1 to 9 show examples of cross-sectional views of composite fibers to which the present invention can be applied. In the figure, + A (margin area) il-1 alkali easily soluble polyester + B (shaded area) is a poorly alkali soluble component, and areas with different diagonal lines indicate different components. Patent applicant Toshi Co., Ltd.'
! l +fl ♀2 +flhualf, father
Figure 75 Figure 9 Hei 812 Army Figure 3 1fl, Figure 1 'ji17

Claims (1)

[Claims] When a fibrous structure containing two or more components, at least one of which is a polyester, is treated with an embrittling agent for the polyester and then treated with an alkali, the alkali treatment temperature is 95° or less. A method for processing a fiber structure, characterized by: