JPS6238479B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for dyeing polyester fiber structures. Hitherto, as fiber structures containing elastic polyester filaments, stockings made of a composite filament of elastic polyester and non-elastic polyester, or power nets made of elastic polyester filaments and other threads have been proposed. However, when a fiber structure containing such an elastic polyester filament is dyed with a disperse dye, the color fastness, especially the wet fastness such as washing fastness, is extremely poor, and it has been found that it cannot be put to practical use at all. . This drawback is noticeable in medium to dark colors.For this reason, the use of fiber structures containing such elastic polyester filaments has been limited to very specific fields that do not require dyeing, and it has been impossible to develop them into clothing applications. It was hot. Conventionally, as a method for improving the wet fastness of a disperse-dyed polyester fiber structure, a method has been used in which the disperse dye on the fiber surface is removed by reduction cleaning using hydrocyphite.
However, according to studies conducted by the present inventors, when the fiber structure contains elastic polyester filaments, almost no reduction cleaning effect can be expected. In other words, in such a fiber structure, the disperse dye is more exhausted on the elastic polyester side due to the difference in dyeability, so the wet fastness of the elastic polyester substantially controls the wet fastness of the entire fiber structure. . The dispersed dye that has been exhausted by the elastic polyester is easily diffused to the fiber surface and easily falls off, so even if the dye on the fiber surface is once removed by reduction cleaning, the dye inside the fiber will continue to reach the fiber surface. As a result, the wet fastness hardly improves. Furthermore, a serious problem with the reduction cleaning method is that the hue of the elastic polyester varies widely before and after reduction cleaning, so it has a practical drawback in that color matching is difficult. The present invention aims to improve the drawbacks of the prior art, and its purpose is to provide a method for improving the wet fastness after dispersion dyeing of fibrous structures containing elastic polyester filaments.
Furthermore, it is an object of the present invention to provide an industrially useful method for improving the wet fastness of dyed products, which causes little change in hue and facilitates color matching. That is, in the dyeing method of the present invention, a fiber structure containing elastic polyester filaments is dyed with a disperse dye, and then treated with an aqueous solution containing tannic acid, and then treated with an aqueous solution containing tartarite to remove tannin. It is characterized in that 0.5 to 5% by weight of each of acid and tartar is added to the fiber structure. The elastic polyester applied to the present invention is a block copolymerized polyether ester having an aromatic polyester as a hard segment and a polyalkylene glycol as a soft segment. As the aromatic polyester constituting the hard segment, terephthalic acid, isophthalic acid, orthophthalic acid, 1,2-diphenoxyethane-P,P'-dicarboxylic acid, or a mixed dicarboxylic acid thereof is used as the acid component, and diol Examples include aromatic polyesters using ethylene glycol, propylene glycol, tetramethylene glycol, 1,4-cyclohexanedimethanol, etc., or mixed diols thereof. On the other hand, examples of the polyalkylene glycol constituting the soft segment include polyethylene glycol, polypropylene glycol, and polytetramethylene glycol. The dyeing method of the present invention can be applied to various elastic polyesters that are a combination of these, but from the viewpoint of forming elastic polyester into a fiber and using it for clothing, it has excellent elastic performance as an elastic polyester. Those with characteristics such as low stickiness and good heat resistance are preferred. Examples of suitable elastic polyesters from this point of view include:
Examples include block copolymerized polyether esters in which a hard segment is an aromatic polyester containing terephthalic acid as a main acid component and tetramethylene glycol as a diol component, and a soft segment is polytetramethylene terephthalate. Here, the acid component is mainly composed of terephthalic acid,
In order to control elastic performance, isophthalic acid or orthophthalic acid may be used in combination. The proportion of terephthalic acid is preferably 50 to 100 mol%, and therefore the proportion of isophthalic acid or orthophthalic acid is preferably 50 to 0 mol%. Polytetramethylene glycol preferably has a molecular weight of 400 to 4000, and preferably accounts for 15 to 70% by weight in the copolymer. The elastic polyester filament applied to the present invention is an elastomer fiber obtained by melt-spinning the above-mentioned elastic polyester, or a composite filament of elastic polyester and non-elastic polyester. In particular, the latter composite filament has excellent crimp performance and is suitable as a material for stockings. From this point of view, polyethylene terephthalate or polytetramethylene terephthalate is preferably used as the non-elastic polyester to be composited with the elastic polyester. The method of the present invention is directed to fiber structures containing such elastic polyester filaments, and the fiber structures include not only yarns made only of elastic polyester filaments, but also mixed fiber yarns mixed with other yarns. It also refers to covering yarns that cover other threads, as well as woven fabrics, knitted fabrics, and nonwoven fabrics using these yarns. The form in which the elastic polyester filament is contained can be selected as appropriate depending on its intended use, appearance, texture, etc. In the treatment method of the present invention, a fiber structure containing elastic polyester filaments is first dyed with a disperse dye. The dye concentration is such that wet fastness becomes a problem, and the amount applied is usually 0.5 to 30% by weight.
It is. The dyeing apparatus, method, etc. are not particularly limited, and the dyeing temperature is usually 50 to 140°C, preferably 80 to 130°C. Since the elastic polyester of the present invention is easily dyeable, it can also be dyed at temperatures of 80 to 100°C.
After dyeing the fiber structure, add 0.5-5% tannic acid.
% by weight, preferably 1 to 4% by weight, and then 0.5 to 5% by weight, preferably 1 to 4% of tartarite. The concentration of tannic acid and tartar and the treatment procedure are important requirements of the method of the invention. The amount of tannic acid and tartar added is 0.5 to 5% by weight. If either is less than 0.5% by weight, the effect of improving wet fastness is insufficient. On the other hand, 5% by weight
If it exceeds this value, the effect will be saturated and not only will it be uneconomical, but it will also have the disadvantage of making the texture of the fibrous structure rough and hard. Note that if the steps of tartar treatment and tannic acid treatment are reversed, the tannic acid will not be fixed and there will be little effect. As a treatment method, it is usually preferable to immerse the fibrous structure in each aqueous solution and treat it at a temperature of usually 50 to 100°C. Of course, other methods such as printing or spraying are also effective. The method according to the invention makes it possible to significantly improve the wet fastness of fibrous structures containing elastic polyester filaments. It is generally known that nylon fibers are treated with tannic acid to fix acidic dyes to improve wet fastness such as washing fastness. In this case, the mechanism of dye fixation is based on the fact that tannic acid is easily adsorbed to polymer chains containing nitrogen atoms, and the adsorbed tannic acid electrostatically repels each other with the same negative charges as the dyed acid dye. The principle is that dye diffusion is suppressed. In contrast, it is clear that the fiber structures applied to the method of the invention contain elastic polyesters, which reduce the wet fastness. Therefore, the effect of the method of the present invention is achieved by treating elastic polyester with tannic acid, but
Considering that elastic polyester does not have nitrogen atoms and disperse dyes do not have ionic dissociative groups, this phenomenon is unexpected and surprising from the previously thought dye fixation mechanism in nylon. I can say that. Of course, the principle of reducing the mobility of dye molecules due to filling of the pores in the matrix with tannic acid can be considered, but this generally has only a small effect in the case of dispersion dyeing. Even if polyethylene terephthalate is disperse dyed and then treated with tannic acid, hardly any improvement in wet fastness can be expected. The present invention will be explained below with reference to Examples. Comparative Example An elastic block copolymerized polyether ester composed of 55% by weight of polytetramethylene terephthalate units and 45% by weight of polytetramethylene glycol units with a molecular weight of 2000 is used as the first composite component, and an inelastic polyester composed of polytetramethylene terephthalate is prepared. was used as the second composite component, and was melt-spun at 255°C side-by-side in a ratio of 1:1, and then hot-stretched to 3.62 times using a hot roller at 60°C to obtain a 25-denier 3-filament composite filament. . knitting the composite filament into stockings;
It was stained with CIDisperse Blue 167 disperse dye (5% owf) at normal pressure of 98°C for 60 minutes. The stocking knitted fabric obtained had a clear dark blue color, a flexible texture, and excellent stretchability.
Washing fastness (staining) according to A-2 is 1-2
It was extremely inferior to the class. The dyed knitted fabric is coated with 2 g of hydrosulfite/
Caustic soda 2g/, nonionic activator 2g/
It was immersed in an aqueous solution of and subjected to reduction cleaning at 90°C for 20 minutes.
The color tone of the obtained knitted fabric had a lighter blue color and was different from that before reduction washing. The washing fastness was grade 2 with only a slight improvement. Example 1 A composite filament knitted stocking fabric made of the same elastic polyester and non-elastic polyester as in Comparative Example 1 was disperse-dyed in the same manner as in Comparative Example, and then dyed with various concentrations of tannic acid and acetic acid (2% OWF). The sample was immersed in an aqueous solution containing tartarite and treated at 80°C for 30 minutes, and then immersed in an aqueous solution containing tartarite and treated at 75°C for 30 minutes. Incidentally, the amount of tartarite applied was 2% by weight. Table 1 shows the evaluation results of the dyed knitted fabrics obtained.

[Table] Example 2 A composite filament stocking knitted fabric was disperse-dyed in the same manner as in Example 1, and dyed with tannic acid and acetic acid (2%
owf) and treated at 80°C for 30 minutes, then immersed in an aqueous solution containing tartarite at various concentrations and treated at 75°C for 30 minutes. The amount of tannic acid added was 3% by weight. Table 2 shows the evaluation results of the dyed knitted fabrics obtained.

【table】

Claims (1)

[Claims] 1. A fiber structure containing elastic polyester filaments is dyed with a disperse dye, and then treated with an aqueous solution containing tannic acid, and then treated with an aqueous solution containing tartarite. A method for dyeing a polyester fiber structure, comprising applying 0.5 to 5% by weight of tartarite and tartar to the fiber structure. 2 Elastic polyester contains 50 to 100 terephthalic acid
Mol% and isophthalic acid or orthophthalic acid 50-0
mole% is the acid component, aromatic polyester having tetramethylene glycol as the diol component is the hard segment, polytetramethylene glycol with a molecular weight of 400 to 4000 is the soft segment, and the soft segment is 15 to 70% by weight of the copolymer. % of the block copolymerized polyether ester. 3. The treatment method according to claim 1, wherein the elastic polyester filament is a composite filament of elastic polyester and non-elastic polyester. 4. The treatment method according to claim 3, wherein the inelastic polyester is substantially polyethylene terephthalate or polytetramethylene terephthalate. 5. The treatment method according to claim 1, wherein the fiber structure is a mixed yarn or a covered yarn containing elastic polyester filaments. 6. The treatment method according to claim 1, wherein the fiber structure is a yarn, a woven fabric, a knitted fabric, or a nonwoven fabric. 7 The amount of disperse dye applied to the fiber structure
The treatment method according to claim 1, wherein the amount is 0.5 to 30% by weight. 8. The treatment method according to claim 1, wherein the dye bath temperature is 80 to 130°C. 9 Processing with an aqueous solution containing tannic acid at a temperature of 50~
The treatment method according to claim 1, wherein the treatment method is immersed at 100°C. 10 Processing with an aqueous solution containing tartarite at a temperature of 50 to 100
The treatment method according to claim 1, wherein the treatment method is immersed at a temperature of .degree.