JPS6330407B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a polyester fiber having excellent anti-pilling properties and surface properties, and a method for producing the same. Polyester fibers, particularly polyester fibers containing polyethylene terephthalate as a main component, have excellent mechanical properties and good texture, and are widely used for clothing, interior decoration, and the like.
However, when used for clothing or interior decoration, it is prone to pilling, which can significantly damage the appearance, and because of the smooth fiber surface, it has a unique mirror luster, and the depth of color cannot be obtained compared to wool or silk. It has the following disadvantages. Various methods have been tried in the past to overcome these drawbacks. As a method of improving pilling property, there is a method of using a low degree of polymerization polyester as seen in Japanese Patent Publication No. 35-8562, but it is difficult to spin due to its low melt viscosity, and even if it is barely spun, There are drawbacks to the manufacturing process, such as the fibers being too weak and stretching difficult. Japanese Patent Publication No. 37-12150 discloses a method of improving spinnability and drawability by adding a thickener when using low polymerization degree polyester, but no significant effect has been obtained. A method of copolymerizing a polyfunctional branching agent such as pentaerythritol is found in Japanese Patent Publication No. 4545/1982, but the effect of improving pilling properties is insufficient. In addition, as another means for improving the pilling property, a method is disclosed in JP-A-50-135331 in which a copolymerized polyester containing phosphate ester bonds is spun into polyester fibers, and then heat treatment, hot water treatment, steam treatment, etc. are performed. , Japanese Patent Publication No. 1973-
No. 123315. However, although this method improves pilling properties, it is not sufficient.
Furthermore, when titanium dioxide, which is commonly used as a matting agent for polyester fibers, is used, the titanium dioxide aggregates into coarse particles because it contains a large amount of phosphorus compounds, which clog the filters of the spinning pack, resulting in extremely This method has a very large disadvantage in the production process, requiring frequent replacement of the spinning pack, and there is little possibility of implementing it industrially. In addition, regarding the improvement of the fiber surface,
No. 39055 contains 0.05 to 30% by weight of silica with a particle size of 10 to 150 microns based on the polymer to form protrusions, and Japanese Patent Publication No. 46-26887 discloses a crystallizing agent for amorphous undrawn fibers. contact,
A method of forming an amorphous core and a crystallized skin by removing a crystallizing agent, and obtaining fine irregularities on the fiber surface by stretching, JP-B No. 43-
No. 14186, Japanese Patent Publication No. 43-16665, there are methods to create irregularities on the fiber surface, such as a method in which fine particulate inert substances are contained and removed with an acid or alkali that has the ability to dissolve the fine particulate inert substances without disturbing the fibers. Although attempts have been made to form
When dyed, due to the cavities that occur inside the fibers,
In either case, the colors were pastel-like, and deep colors could not be obtained. The present inventors have discovered that these two properties of polyester fibers
The present invention was arrived at as a result of studies aimed at simultaneously improving these two drawbacks. That is, the present invention provides a composite material in which 80% or more of repeating units are ethylene terephthalate units, 0.1 to 10% of all ester bonds are phosphate ester bonds, and 0.5 to 10% by weight of silica sol with a particle size of 80 millimicrons or less is contained. Polyester fiber made by spinning and drawing polymerized polyester, (i)
An advantage characterized in that the polyester fiber is treated with hot water or steam and a soluble or degradable substance, or (ii) the polyester fiber is treated with hot water containing a soluble substance or a degradable substance. This is a method for producing polyester fibers with excellent anti-pilling properties and surface properties. The easiest way to improve the pilling properties of polyester fibers is to reduce the high tenacity of polyester fibers to that of natural fibers. However, in order to reduce the strength to the extent that the pilling property is improved,
The degree of polymerization must be lowered to such an extent that the spinnability is almost impaired, and this is not an effective means for improving pilling properties. In the present invention, a phosphate ester bond that is susceptible to hydrolysis is introduced in advance, and the particle size is
A polyester fiber having a strength of 3.5 to 5.0 g/dr and an elongation of 30 to 50%, which is obtained by spinning and drawing a polyester containing 0.5 to 10% by weight of silica sol of 80 millimicrons or less, is treated with hot water or steam, and the polyester is By treating the fiber with a soluble substance or degradable substance, or by treating the polyester fiber with hot water containing a soluble substance or a degradable substance, an extremely fine and complex uneven shape is developed over the entire surface of the fiber. It gives the same depth of color after dyeing as silk or wool, and at the same time increases the strength of the fiber by 1.5~
2.8g/dr, JIS L with elongation reduced to 15-30%
-1076-3 to 5 in pilling test using 1978A method
It provides excellent anti-pilling properties. When polyester fibers containing phosphate ester bonds are hydrolyzed by treatment with hot water or steam, the strength of the fibers decreases by about 0.5 g/dr, and the fiber strength can be slightly lowered. Furthermore, when polyester fibers containing silica are reduced in weight with alkali, the fiber strength increases.
It decreases by about 0.2 to 0.3 g/dr. However, the present inventors have proposed that the polyester fiber containing phosphoric acid ester bonds and silica be treated with hot water or steam and treated with a soluble or degradable substance of the polyester fiber, or (ii) of the polyester fiber. It has been found that when treated with hot water containing soluble or degradable substances, the fiber strength decreases by about 2 g/dr. This proves that the combination of the two is unexpectedly effective, and is considered to be more than just a combination. As a result of the above-described treatment, a unique random surface of irregular irregularities is formed on the surface of the fiber. In the present invention, the term "random surface" refers to a surface on which irregularities are arranged, both in height and in irregular intervals. Regarding the uneven state forming the random surface,
In the present invention, it is defined by the plane distance X between the lowest point of a recess existing in the outer circumferential direction perpendicular to the fiber axis and the lowest point of an adjacent recess. That is, the term "unevenness" as used in the present invention means the above-mentioned plane distance (interval), and does not mean the height (depth) of the unevenness. Through the above treatment, the individual Xs are different, and each X is uneven, and each X is approximately 0.1 to 0.8 microns, but in the present invention,
The plane distance in the outer circumferential direction perpendicular to the fiber axis of unevenness that is not uniformly spaced and satisfies 0.2 to 0.7 microns is 10
In the present invention, a random surface is defined as a random surface having a density of 10 to 50 particles per micron, and in which fine irregularities smaller than 0.2 microns exist singly or partially overlapping within the uneven portion. It is thought that this contributes to the excellent effect. That is, according to the present invention, in order to eliminate the specular gloss peculiar to polyester fibers and increase the depth of color, it is necessary to form a random surface with irregular irregularities as described above on the fiber surface, and to It is important that the irregularities forming the random surface further include fine irregularities of 50 to 200 millimeters. When the above-mentioned X is only 0.2 microns or less, no decrease in specular reflectance is observed, and the depth of the color after dyeing is not much different from that of conventional dyes, so it is difficult to recognize the quality improvement effect. Furthermore, if X is larger than 0.7 microns, the reflectance of visible light will be high, and the color will tend to become dull and whitish, making it even less effective. X is
Even if it is greater than 0.2 microns and smaller than 0.7 microns, if the density is not 10 or more per 10 microns of length in the outer circumferential direction perpendicular to the fiber axis, the effect of improving color development and color depth will be insufficient. In order to obtain the polyester fiber of the present invention that has good pilling properties and has a fine and complicated uneven shape, 80% or more of the repeating units are ethylene terephthalate units, and 0.1% of the total ester bonds are made of ethylene terephthalate units.
A copolymerized polyester containing ~10% phosphate ester bonds and 0.5~10% by weight of silica sol with a particle size of 80 millimicrons or less is required. The ratio of phosphate ester bonds to total ester bonds is 0.1
If it is less than 10%, the pilling property improvement effect will not be sufficient, and if it exceeds 10%, the strength of the fiber will be severely reduced, which is not preferable. In addition, when the particle size of the silica sol exceeds 80 millimicrons, the X, which indicates the unevenness of the fiber surface layer eluate, becomes large, the unevenness that forms a random surface decreases, and the dullness of the color and the white spots after dyeing are reduced. It's noticeable and undesirable. In addition, if the amount of silica sol added is less than 0.5% by weight, the unevenness of the random surface will be insufficient and the effect of improving color depth and gloss will not be observed, and if it is added in excess of 10% by weight, spinning will be difficult. It becomes difficult. In order to introduce a phosphate ester bond into this copolymerized polyester, a phosphorus compound having the ability to form a phosphate ester bond is introduced into the copolymerized polyester. In the direct esterification method, the addition copolymerization may be carried out at any stage from the start of the esterification reaction of terephthalic acid and ethylene glycol to just before the completion of the polycondensation reaction. For example, phosphoric acid, phosphorous acid, trimethyl phosphate, dibutyl phosphate, tributyl phosphate, hydroxyethyl phosphate, dihydroxyethyl phosphate, trihydroxyethyl phosphate, trimethyl phosphite, dibutyl phosphite, tributyl phosphite. , hydroxyethyl phosphite, dihydroxyethyl phosphite, trihydroxyethyl phosphite, and the like. As a method for incorporating silica sol into copolymerized polyester, colloidal silica in which fine silica particles with a particle size of 80 millimicrons or less are present in the form of single particles is used, and in the transesterification method, immediately before the start of the transesterification reaction of dimethyl terephthalate and ethylene glycol, or In the direct esterification method, it may be added at any stage immediately before the start of the esterification reaction between terephthalic acid and ethylene glycol or at any stage during the reaction. The most preferred method of addition is to add colloidal silica before or at the beginning of the esterification or transesterification reaction in a manner that prevents rapid dispersion of the dispersion. Colloidal silica refers to a colloid in which fine particles containing silicon oxide as a main component are used as a dispersion medium in water, monohydric alcohols, diols, or mixtures thereof. In the hot water or steam treatment of the present invention, the temperature is preferably 80°C or higher, preferably 95°C or higher, and 80°C or higher.
If it is less than that, the effect of improving pilling property will be small, which is not preferable. Further, in the case of steam treatment, the temperature is preferably 110 to 150°C. This hot water or steam treatment is preferably carried out at any stage after stretching, and may be carried out alone or in combination with finishing and dyeing steps. When water is contained in the liquid used to treat polyester fibers with a soluble or degradable substance, the treatment may be carried out simultaneously with the treatment or dyeing with the soluble or degradable substance. Although the treatment of polyester fibers with a soluble substance or a decomposable substance may be carried out at any stage after stretching, it is preferable to carry out the treatment before dyeing because color matching is easier. or,
This treatment is suitably an alkali weight loss treatment using an alkaline aqueous solution such as caustic soda, but any treatment with a liquid containing a soluble substance or a decomposable substance for polyester fibers may be used, and is not limited to an alkali weight loss treatment. When polyester fibers are used for clothing or interior decoration, especially for clothing, the fibers are usually matted, and only in special cases are they not matted. When using titanium dioxide, which is commonly used for matting polyester fibers, in the case of polyester containing a large amount of phosphorus as in the present invention, the titanium dioxide aggregates and becomes coarse particles that severely clog the filters of the spinning pack. However, this method necessitates frequent replacement of the spinning pack, which causes major trouble in the manufacturing process and makes implementation difficult.
There are methods for matting polyester fibers other than titanium dioxide, but all of these methods are special methods compared to titanium dioxide, are disadvantageous in terms of manufacturing process and cost, and are only intended for matting. This alone has very little merit from an industrial perspective. In contrast, in the present invention, polyester fibers containing fine silica sol are treated with a soluble or degradable substance for the polyester fibers, and the surface of the fibers is made to have extremely fine and complex uneven shapes as described above, thereby achieving matting. It also provides important properties not found in conventional polyesters, such as flexibility and depth of color after dyeing. Also,
When treating polyester fibers with soluble or degradable substances, it is appropriate to carry out an alkali weight loss treatment using an alkaline aqueous solution such as caustic soda before dyeing, but the alkali weight loss treatment is industrially carried out at a temperature close to the boiling point of water, i.e. 90 to 100°C. This is usually done.
Furthermore, polyester fibers are usually dyed at high temperatures of around 130°C. Therefore, when the method of the present invention is carried out industrially, hot water or steam treatment is carried out twice without any special measures, which increases the strength loss of the fibers due to hydrolysis and increases the pill resistance. The expression of sexuality can be made more advanced. In addition, when phosphoric acid ester bonds and silica are contained in polyester fibers, when the fibers are treated with hot water or steam and treated with soluble or degradable substances of the polyester fibers, the fiber strength decreases significantly. , the fiber strength before these treatments is high. Therefore, manufacturing processes before these treatments, such as spinning, drawing, twisting, knitting, and weaving for filaments, and spinning, drawing, crimping, cutting, spinning, and weaving for staple fibers. It has the advantage of causing very little trouble during processes such as knitting and weaving. That is, the present invention provides a polyester fiber that causes very few troubles in the manufacturing process and has good pill resistance and depth after dyeing. In the present invention, one or more third components are blended or melt-mixed into the copolymerized polyester at any stage before the completion of the polycondensation reaction or after the completion of the polycondensation reaction until spinning, and the polyester By lowering the melting point and secondary transition point of the fiber, anti-pilling treatment can be carried out at lower temperatures. In this case, it is possible to use it in combination with a treatment that gives the surface irregularities, and other physical properties of the polyester fiber can also be improved thereby. The third component refers to a compound having the ability to form one or more ester bonds, such as isophthalic acid, phthalic acid,
Organic carboxylic acids such as adipic acid, sebacic acid, trimesic acid, naphthalene dicarboxylic acid, sulfoisophthalic acid and their functional derivatives, propylene glycol, neopentyl glycol, 1.
Examples include alcohols such as 4-butanediol, 1.4-cyclohexanedimethanolpentaerythritol, polyethylene glycol, and polypropylene glycol, and functional derivatives thereof. Next, the present invention will be explained with reference to examples, but the present invention is not limited to the following examples. In the examples, all "parts" indicating the amount added mean parts by weight. Intrinsic viscosity [η] is a value (unit: dl/g) obtained by dissolving polyester in a mixed solvent of equal weights of phenol and tetrachloroethane and measuring the solution at 30°C. Examples 1 to 5, Comparative Examples 1 and 2 83 parts of terephthalic acid, 62 parts of ethylene glycol,
14.4 parts of aqueous silica sol with a particle size distribution in the range of 10 to 20 millimicrons at a concentration of 20% by weight and 0.038 parts of antimony trioxide were made into a slurry and charged into a reactor, and the mixture was heated at 250°C and 1.5 kg/cm ² G to 4 After esterification for an hour, tributyl phosphate was added, the pressure was gradually reduced and the temperature was increased, and the pressure was 1 mmHg or less and the temperature was
After reaching 280℃, a polycondensation reaction was carried out for 2 hours,
The obtained polyester was extruded from the bottom of the reactor to obtain polyester chips. At this time, adjust the amount of tributyl phosphate added so that the phosphate ester bond is 0.01~
Each chip was obtained at a rate of 10%. Subsequently, the polyester chips were dried, spun, and then conventionally drawn to obtain 100 denier/36 polyester filaments. At this time, polymerization, spinning, and drawing were performed smoothly without any trouble for each chip. Next, this polyester filament was knitted into a 22-gauge tube and subjected to alkali weight loss with a 4% by weight aqueous solution of caustic soda at 95°C. At this time, care was taken to keep the alkali weight loss rate from 3 to 6%. Each knitted fabric was dyed using the following recipe, and a pilling test was conducted using the JISL1076-1978A method. The results are shown in Table 1.

[Table] From this, it was confirmed that a phosphate ester bond is necessary. In addition, in each example, the color was deeper and the gloss was improved compared to conventional polyester. Furthermore, when the uneven shape of the fiber surface is determined using scanning electron micrographs, it is found that each example has minute unevenness consisting of walls of a granular structure of 50 to 200 millimicrons, and furthermore, it has a random irregular unevenness including this fine unevenness. surface was formed. Although X representing the uneven shape was not constant, unevenness satisfying 0.2 micron<X<0.7 micron existed at a density within the range of 10 to 50 pieces per 10 microns. Example 6, Comparative Examples 3 and 4 Tube-knitted samples were prepared in the same manner as in Example 3, and alkali weight loss was performed at 60°C, 70°C, and 80°C, and dyeing was omitted. The results of the alkali weight loss and pilling tests are shown in Table 2, confirming the necessity of hot water treatment at a temperature of 80°C or higher.

[Table] Examples 7 to 11, Comparative Examples 5 and 6 Terephthalic acid 83 parts, ethylene glycol 62 parts,
Antimony trioxide, aqueous silica sol at a concentration of 20% by weight with a particle size distribution in the range of 10-20 millimicrons
Make 0.038 part into a slurry and charge it into the reactor,
After esterification for 4 hours at 1.5Kg/ ^cm2・G, 1.58 parts of dibutyl phosphate was added, and the pressure was gradually reduced and the temperature was increased until the pressure was 1 mmHg or less and the temperature was 280℃ for 50 minutes.
After reaching the temperature, a polycondensation reaction was carried out for 2 hours, and the resulting polyester was extruded from the bottom of the reactor to obtain polyester chips. At this time, the amount of silica sol added was varied from 0.1% by weight to 15% by weight to create various polyester chips. Next, the polyester chips are dried, spun, and then stretched in the usual way.
100 denier/36 polyester filaments were obtained. In the case of 12% and 15% by weight of silica sol, the spinnability was poor and no samples could be obtained. Next, this polyester filament was knitted into a 22-gauge tube, subjected to alkali reduction and dyeing in the same manner as in Example 1, and the reflectance of each knitted material was measured using a Hitachi self-recording spectrophotometer.
Measurements were made using an EPR-2 model, and changes in color depth were determined from changes in reflectance, and irregularities on the fiber surface were determined from scanning electron micrographs. A pilling test was also conducted and the results are shown in Table 3.

[Table] With 0.1% silica sol, the fiber surface does not have a random surface, the X representing unevenness is 0.7 microns or more, the decrease in reflectance is small, there is no depth of color after dyeing, and there is no improvement in gloss. It's hard to admit. On the other hand, those containing 0.5% by weight or more of silica sol are 50%
It has fine irregularities with a grain structure of ~200 millimeters,
A random surface of irregular irregularities including these fine irregularities was formed on the fiber surface. Further, unevenness satisfying the X value of 0.2 micron to 0.7 micron was present at a density within the range of 10 to 50 pieces per 10 micron. In addition, these had a large decrease in reflectance, the depth of the color after dyeing was observed, and the gloss was also good and smooth. Example 12 83 parts of terephthalic acid, 62 parts of ethylene glycol,
20 with particle size distribution ranging from 30 to 40 millimicrons
14.4 parts by weight of aqueous silica sol and 0.038 parts of antimony trioxide were made into a slurry and charged into a reactor.
After esterification at 250℃ and 1.5Kg/ ^cm2・G for 4 hours, 1.4 parts of trimethyl phosphate was added, and the pressure was gradually reduced and the temperature was increased until the pressure was reduced to 1 mmHg or less and the temperature was reduced for 50 minutes.
After reaching 280℃, a polycondensation reaction was carried out for 2 hours,
The obtained polyester was extruded from the bottom of the reactor to obtain polyester chips. The [η] of this polyester chip was 0.67, and the amount of phosphate ester bonds was 3%. Subsequently, this polyester chip was dried, then spun and stretched to obtain a staple of 3 dr x 51 mm. From this staple, a number 30 spun yarn is obtained,
I used 30 gauge tube knitting. The spinning process went smoothly without any trouble. This knitted fabric was subjected to alkali reduction and dyeing in the same manner as in Example 1. A pilling test was conducted on this product and it was grade 5. Further, the depth of the color was also developed, and an improvement in the gloss was also observed.

Claims (1)

[Claims] 1 More than 80% of the repeating units consist of ethylene terephthalate units, and 0.1 to 10 of the total ester bonds
% of phosphate ester bonds and 0.5 to 10% by weight of silica sol with a particle size of 80 millimicrons or less is spun and drawn to form a polyester fiber, (i) treated with hot water or steam, and Excellent anti-pilling properties and surface properties characterized by treating the polyester fiber with a soluble or degradable substance, or (ii) treating the polyester fiber in hot water containing a soluble or degradable substance. A method for producing polyester fiber having