JPS5818447B2 - Manufacturing method of anti-pilling polyester fiber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing polyester fibers having very good anti-pilling properties.

Polyester fibers, especially polyethylene terephthalate fibers, have a higher Young's modulus and a higher elastic recovery rate than other synthetic fibers, such as polyamide fibers and polyacrylonitrile fibers, so when made into woven or knitted fabrics, they tend to have stiffness and wrinkles. This fiber is widely used as a material for clothing because it has excellent abrasion resistance, heat resistance, and chemical resistance.

However, this fiber has somewhat excessive cutting strength, knotting strength, and abrasion strength, so when used as a woven or knitted fabric, pilling occurs due to single thread breakage or binding of the fibers on the surface of the woven or knitted fabric. □ Has a drawback that significantly worsens its appearance
As a result, its use as high-end clothing has been narrowed down.

Conventionally, as a method for improving the tendency to pill, that is, the pilling property, there has been known a method of spinning low-strength fibers using polyester having a low degree of polymerization and having an intrinsic viscosity of 0.45 or less.

However, in order to industrially produce polyester fibers with sufficiently satisfactory anti-pilling properties using this method,
The melt viscosity of the raw material polyester becomes too low, causing problems such as dropping during spinning, making melt spinning extremely difficult.

As a result of intensive research on a method for easily producing anti-pilling polyester fibers, the present inventor added a specific amount of a specific phosphorus compound when synthesizing polyester to synthesize a polyester with a relatively high degree of polymerization. It has been found that anti-pilling polyester fibers with a predetermined low degree of polymerization can be easily obtained by melt-spinning and heat-treating the obtained phosphorus-containing polyester fibers under specific conditions.

The present invention was completed as a result of further research based on this knowledge.

That is, the present invention reacts a difunctional carboxylic acid, mainly terephthalic acid, or its ester-forming derivative with a glycol, mainly ethylene glycol, or its ester-forming derivative, to produce a glycol ester and a difunctional carboxylic acid. / or a first step reaction to form a low polymer thereof, a second step reaction to polycondensate the reaction product to form a polyester, and a step of melt spinning the polyester. At least one phosphorus compound selected from the group consisting of phosphoric acid, phosphorous acid, phosphonic acid, phosphorous acid, and derivatives thereof is produced in the polyester at any stage from the completion of the first-stage reaction until the completion of the melt-spinning process. The content of phosphorus atoms is 0,0
By adding an amount in the range of 2 to 1.5% by weight, the intrinsic viscosity is 0.
The intrinsic viscosity of the polyester fiber is reduced to 0.4 by heat treating the hind leg polyester fiber at a temperature of 100°C or more for 1 minute or more.
5 or less.

The difunctional carboxylic acid or its ester-forming derivative used as a raw material for polyester in the method of the present invention includes terephthalic acid or its lower alkyl ester,
The main targets are phenyl esters, etc., but some of them are also applicable to other dibasic acids such as isophthalic acid, P-β-oxyethoxybenzoic acid, diphenylsulfone dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenoxyethane dicarboxylic acid, adipic acid, Sepatic acid, 5-sodium sulfoisophthalic acid, etc. or ester-forming derivatives thereof may be substituted.

In addition, as glycols or their ester-forming derivatives, we mainly target ethylene glycol or its lower fatty acid esters, oxides, cyclic carbonate esters, etc., but some of them are also used as other dioxy compounds such as glopylene glycol, trimethylene glycol, Tetramethylene glycol, neopentylene glycol, 1,4-hexanediol, 1,4-cyclohexane dimetatool, ■4-bisoxyethoxybenzene, bisphenol A1 polyoxyethylene glycol, etc., or ester-forming derivatives thereof, etc. A thousand replacements are also possible.

Any method can be used to produce polyester from such acid components and glycol components.

In the case of polyethylene terephthalate, for example, an ester-forming derivative of terephthalic acid such as dimethyl terephthalate and ethylene glycol may be transesterified, terephthalic acid and ethylene glycol may be directly esterified, or terephthalic acid may be directly esterified with ethylene glycol. Ethylene glycol ester and/or terephthalic acid are produced by addition reaction of ethylene oxide to acid.
Or, it is produced by a first stage reaction in which a low polymer thereof is produced, and a second stage reaction in which the first stage reaction product is heated to a high temperature under reduced pressure to undergo polycondensation.

Further, any method can be used for melt spinning the obtained polyester.

In addition, in the production of the above polyester, a transesterification catalyst, an esterification catalyst, a polycondensation catalyst and ordinary additives,
For example, matting agents, light stabilizers, antistatic agents, antioxidants,
Fluorescent brighteners and the like can be used without any problem if necessary.

The phosphorus compounds used in the present invention include phosphoric acid, phosphorous acid, phosphonic acid, phosphorous acid, and derivatives thereof, and examples of the derivatives include polymers and esters.

Examples of polymers include polyphosphoric acids such as diphosphoric acid and triphosphoric acid, and polyphosphorous acids such as diphosphoric acid. Examples of esters include aryl groups such as phenyl, naphthyl, and biphenyl;
Substituted aryl groups such as tolyl, chlorophenyl, bromophenyl, methoxyphenyl□, alkyl groups such as methyl, ethyl, propyl, butyl, octyl, nonyl, substituted alkyl groups such as ethoxyethyl, butoxyethyl, chloroethyl, bromoethyl, cyclohexyl, deca Cycloalkyl groups such as hydronaphthyl, methylcyclohexyl,
Examples include monoesters, diesters, triesters, mixed esters, etc. based on substituted alkyl groups such as chlorocyclohexyl and bromocyclohexyl.

In addition, if the amount of the above-mentioned phosphorus compound used is too small, the degree of polymerization cannot be sufficiently lowered by heat treatment, and on the other hand, if it is too large, the properties of the polyester will deteriorate. The amount is 0.02~
An amount in the range of 1.5% by weight is suitable.

The phosphorus compound may be added at any time after the first stage of the reaction in the polyester production is completed, after synthesizing the polymer by polycondensation reaction, until the completion of the melt-spinning process of forming the polyester into a fiber. In particular, it is preferable to add the polyester from the start of the polycondensation reaction to the end of the polycondensation reaction while the polyester is still in a molten state.

In the present invention, the intrinsic viscosity of the polyester fiber obtained by spinning should be 0.5 or more, and usually up to about 0.7.

If it is lower than 0.5, the melt viscosity during spinning becomes too low, making it impossible to avoid problems during spinning, which is the object of the present invention.

In addition, the intrinsic viscosity as used in the present invention is a value determined by a conventional method from the viscosity measured at 35° C. using 0-chlorophenol as a solvent, and represents the degree of polymerization of the polyester.

In the present invention, the intrinsic viscosity of polyester fiber is 0.45.
The heat treatment performed to lower the temperature below can be performed at any processing stage from immediately after spinning to final products such as woven or knitted fabrics.

In particular, it is advantageous to perform the dyeing process before, during, or at the same time as the dyeing process and dyeing/finishing process.

This heat treatment may generally be carried out in steam, water, an aqueous solution or suspension, or in any other organic medium that does not adversely affect the polyester.

Further, the purpose can also be sufficiently achieved by a dry method.

The optimum conditions for heat treatment vary depending on the form of the object to be treated, the degree of polymerization, the amount of phosphorus compound added, the treatment medium, etc.
Generally, the treatment temperature is 100 DEG C. or higher and lower than the softening point, preferably 120 DEG to 200 DEG C., and the treatment time is usually 1 minute or more, preferably 5 to 150 minutes.

If the temperature does not reach 100° C., the intrinsic viscosity cannot be sufficiently lowered even if the treatment is carried out for a long time, and if the temperature is too high, the treated material will be deformed or deteriorated.

Further, if the treatment is carried out for less than 1 minute, the intrinsic viscosity cannot be lowered even if the temperature is increased.

There is no problem in lengthening this processing time, but 15
There is no particular benefit if you do it for more than 0 minutes.

According to the method of the present invention, polyester fibers with excellent anti-pilling properties can be produced extremely easily, and the resulting fibers are expected to have excellent properties such as color tone, dyeability, and flame retardancy. It will be done.

The present invention will be further explained below with reference to Examples.

Note that parts in the examples mean parts by weight.

Example 1 110 parts of dimethyl terephthalate, 70 parts of ethylene glycol, 0.7 part of O-benzoylbenzoic acid methyl ester, 0.07 part of calcium acetate, and 0.04 part of antimony trioxide were mixed and heated for 1.3 hours. .

Meanwhile, add methanol dropwise and heat to 170℃~230℃.
The transesterification reaction was completed by raising the temperature to °C.

Next, 0.8 part of trimethyl phosphate (the content of phosphorus atoms in the produced polyester is 0.16% by weight) was added to this product, and the temperature was increased and the pressure was reduced to a final temperature of 0.7 mmHg and 270 mmHg.
A polycondensation reaction was carried out at ℃ for 3 hours to obtain a polymer having an intrinsic viscosity of 0.54.

This polymer was melt-spun and drawn in a conventional manner to obtain a polyester filament having an intrinsic viscosity of 0.52.

This filament was treated for 10 minutes in hot water maintained at the temperature shown in Table 1.

The intrinsic viscosity of the filament after treatment was as shown in Table 1.

Example 2 The filament having an intrinsic viscosity of 0.52 produced in Example 1 was treated in hot water maintained at 120° C. for the time shown in Table 2.

The intrinsic viscosity of the filament after treatment was as shown in Table 2.

Example 3 A filament with an intrinsic viscosity of 058 produced in the same manner as in Example 1 was coated with a carrier (NOF KK; CB-7) of 0.
80°C and 100°C as shown in Table 2 in hot water containing 1% by weight.
℃, 120°C, and 150°C for 5 minutes each.

The intrinsic viscosity of the filament after treatment was as shown in Table 3.

Example 4 A filament with an intrinsic viscosity of 0.52 produced in the same manner as in Example 1 was dyed in advance at 95°C with Dispersol Fast Curlet B, and the dyed filaments with an intrinsic viscosity of 0.51 are shown in Table 4. The results shown in Table 4 were obtained by treatment for 10 minutes in hot water maintained at the same temperature.

Example 5 110 parts of dimethyl terephthalate, 70 parts of ethylene glycol, 0.07 part of calcium acetate, and 0.04 part of antimony trioxide were mixed and heated for 3 hours.

In the meantime, add methanol and heat to 170℃~230℃.
The transesterification reaction was completed by raising the temperature to ℃.

Next, this product is heated and depressurized to a final size of 0.2 mm.
A polycondensation reaction was carried out using Hg at 285° C. for 3 hours, and at the end of the reaction, 3.0 parts of diphenyl phosphate (the content of phosphorus atoms in the polyester produced was 0.33% by weight) was added.

This polymer is spun and stretched in a conventional manner to give an intrinsic viscosity of 0.
62 polyester filaments were obtained.

When this filament was kept in hot water kept at 150°C for 20 minutes, the intrinsic viscosity was 0.41, which is JISL-
A pilling resistance test was conducted according to method A of No. 1076-1967, and the pilling resistance was grade 4.

Claims (1)

[Claims] 1. Glycol esters and/or difunctional carboxylic acids are produced by reacting difunctional carboxylic acids mainly consisting of terephthalic acid or their ester-forming derivatives with glycols mainly consisting of ethylene glycol or their ester-forming derivatives.
or a low polymer thereof, a second step of polycondensation reaction of the reaction product to form a polyester, and a step of melt-spinning the polyester. At least one phosphorus compound selected from the group consisting of phosphoric acid, phosphorous acid, phosphonic acid, phosphorous acid, and derivatives thereof is produced in the polyester at any stage from the completion of the first-stage reaction until the completion of the melt-spinning process. The content of phosphorus atoms is 0.02 to 1.
The intrinsic viscosity of the polyester fiber is increased by adding an amount in the range of 5% by weight to produce a phosphorus-containing polyester fiber with an intrinsic viscosity of 0.5 or more, and then heat-treating the vaginal polyester fiber at a temperature of 100°C or more for 1 minute or more to increase the intrinsic viscosity of the polyester fiber. 1. A method for producing anti-pilling polyester fibers, characterized in that the anti-pilling properties of polyester fibers are reduced to 0.45 or less.