JPH0726416A - Polyester fiber with improved room temperature soil release - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide a polyester fiber having an excellent soil release property when subjected to a washing treatment using not only hot water but also water at room temperature. [Structure] At least a part of the polyester terminal is represented by the following formula (I) A polyester fiber made of a polyester obtained by copolymerizing a polyoxyalkylene polyether represented by the following in an amount of 0.5 to 10% by weight.

Description

Detailed Description of the Invention

The present invention relates to antifouling polyesters, and more particularly to polyester fibers having improved cold soil release.

[0002]

2. Description of the Related Art Polyester fiber has excellent dimensional stability,
It is used in all fields of clothing because of its excellent properties such as being strong and less likely to wrinkle. In particular, a variety of uniforms have been used in recent years in hospitals, hospitals, food industry, offices, etc., and there are remarkable developments in the field of polyester fiber textile uniforms. However, the polyester fiber having such excellent properties is also hydrophobic, so that it is significantly inferior in water absorbency and hygroscopicity, and oily stains are more likely to adhere to it than in hydrophilic fibers such as cotton, and are difficult to remove during washing. There is a problem that it is easy to recontaminate. This is a problem that has always been raised since the development of polyester fibers in the field of textile uniforms, and many methods have been proposed to solve this problem.

Among them, the present inventors have prepared a composition obtained by blending a polyoxyethylene-based polyether, which is obtained by copolymerizing ethylene oxide with a specific olefin oxide and insolubilized in water, in a polyester. It was found that the property is remarkably improved (JP-A-2-269).
762 and JP-A-3-182546). However, in this method, since the polyether is merely physically dispersed in the polyester, the washing durability is limited.

On the other hand, as a method for imparting hydrophilicity to a polyester, a method of copolymerizing a polyoxyalkylene-based polyether with the polyester is known. For example, polyoxyethylene glycol phenyl glycidyl ether (JP-A-1-236236) or It is disclosed that a polyester having excellent water absorption and sweat absorption can be obtained by copolymerizing polyoxyethylene glycol methyl 1,2-dihydroxypropyl ether (JP-A-1-234420). Also by this method, excellent antifouling properties can be imparted while having sufficient washing durability as compared with regular products.

However, all of the polyester fibers obtained by the above technique show an excellent soil release property when washed in warm water of 40 ° C. defined by the JIS evaluation method, but practically they are generally used at home. It was found that there is a problem that the soil release property is not fully exhibited when washed with tap water at room temperature.

In order to impart higher hydrophilicity to the polyester, the present inventors have known ω-hydroxypolyalkylenebenzenesulfonic acid alkali metal salt and ω-hydroxypolyalkylenecresol sulfone, which are known as polyethers having a sulfonic acid group. Acid alkali metal salt (GB868150) was copolymerized with polyester, and the soil release property was evaluated. However, these modifiers were originally intended to improve the dyeability, and the soil release property in normal temperature water was insufficient as in the above technique.

[0007]

SUMMARY OF THE INVENTION Therefore, the inventors of the present invention have excellent soil release properties not only in warm water of 40 ° C. but also in normal temperature water used for general household washing (here, 10 ° C. for convenience). Focusing on the chemical structure of the polyether for the purpose of providing a polyester fiber having the following, as a result of diligent studies, it was found that the room temperature soil release property is specifically improved only when a polyether having a specific structure is used. That is, the present invention has been reached.

[0008]

That is, according to the present invention, at least a part of a polyester terminal containing ethylene terephthalate as a main constituent unit has the following general formula (I).

[0009]

[Chemical 2]

(In the formula, M is a hydrogen atom, a monovalent metal or a quaternary phosphonium salt. R is the same or different hydrocarbon group having 1 to 20 carbon atoms, and at least one is a carbon number. It is a hydrocarbon group of 6 or more, p is an integer of 1 to 5, q is an integer of 1 to 5, and p + q ≦ 5.
m is an integer of 15 to 120. ), Which is a polyester obtained by copolymerizing a polyoxyalkylene-based polyether having a molecular weight of 6000 or less, wherein the copolymerization amount is 0.5 to 10% by weight with respect to the matrix polyester, and improved room temperature soil release It is a polyester fiber having properties.

The polyoxyalkylene-based polyether used in the present invention (hereinafter referred to as polyether).
Is represented by the above formula (I).

In the formula, M represents a hydrogen atom, a monovalent metal or a quaternary phosphonium salt. As the metal, Na, Li,
K, Ca, Mg, Al, etc., and especially Na, K, L
i and Ca are preferable. When M is a quaternary phosphonium salt, it is represented by PR ¹ R ² R ³ R ⁴ and R ¹ , R ² , R ³
Alternatively, R ⁴ is the same or different group selected from an alkyl group and an aryl group.

R is a hydrocarbon group having 1 to 20 carbon atoms and may be independently the same or different in the molecule.
At least one of them must be a hydrocarbon group having 6 or more carbon atoms. As the hydrocarbon group, an alkyl group is preferable, and an alkyl group having 6 to 14 carbon atoms is particularly preferable.

P is an integer of 1 to 5, and q is an integer of 1 to 5. p and q satisfy p + q ≦ 5. p is 1 or 2
Is preferred, and q is preferably 1 or 2. Further, the substitution position of the sulfonic acid group and the R group on the phenoxy group may be any position.

M represents the number of oxyethylene units in the polyether and is an integer of 15 to 120. When attempting to copolymerize a polyether having m of less than 15 with polyester, a large amount of polyether is required to obtain a sufficient soil release property. In such a case, the polyester itself is blocked and the polyester itself is blocked. It is not possible to sufficiently increase the degree of polymerization of, and it is not possible to secure the mechanical properties of the obtained fiber. On the other hand, when m is larger than 120, the reaction between the polyether and the polyester does not proceed sufficiently, and the result is the same as when the polyether is mixed and dispersed in the polyester, and high washing durability cannot be maintained. The molecular weight of the polyether is 6000 or less, preferably 5000 or less, and particularly preferably 4500 or less.

The above-mentioned characteristics of the compound are surprisingly remarkable when the compound disclosed in GB mentioned above as a dyeability improving agent is provided with a hydrocarbon group having 6 or more carbon atoms as a substituent on the benzene ring. Improving is to exert the function of significantly improving the soil release property in normal temperature water, which is unrelated.

The polyether represented by the formula (I) is capable of opening ethylene oxide at a high temperature and a high pressure using a hydroxybenzenesulfonic acid sulfonic acid metal salt or phosphonium salt having a suitable hydrocarbon substituent and a suitable base catalyst. It can be easily produced by ring polymerization.
It is known that this polymerization process proceeds stepwise,
By adjusting the amount of ethylene oxide charged, it is possible to produce a polyether having a molecular weight according to the purpose. The molecular weight of the produced polyether can be easily determined by quantifying the terminal hydroxyl group.

In the present invention, the polyester copolymerized with the polyether is a polyester having terephthalic acid as a main acid component and ethylene glycol as a main glycol component. In such polyester, a part of its acid component, terephthalic acid, may be replaced with another difunctional carboxylic acid. Examples of such other carboxylic acid include diphthalic acid such as isophthalic acid, 5-sodium sulfoisophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenoxyethanedicarboxylic acid, β-oxyethoxybenzoic acid and p-oxybenzoic acid. Examples thereof include functional aromatic carboxylic acids, sebacic acid, adipic acid, and difunctional aliphatic carboxylic acids such as oxalic acid. Further, a part of the ethylene glycol component may be replaced with another glycol component, and examples of such a glycol component include trimethylene glycol, tetramethylene glycol, pentamethylene glycol,
Hexamethylene glycol and the like, and other diol compounds such as cyclohexane-1,4-dimethanol, neopentyl glycol, bisphenol A, bisphenol S, aliphatic, alicyclic and aromatic diol compounds,
Examples thereof include polyoxyalkylene glycol whose both terminals are unblocked.

The polyester can be produced by any method. For example, polyethylene terephthalate can be described by direct esterification reaction of terephthalic acid and ethylene glycol, transesterification reaction of lower alkyl ester of terephthalic acid such as dimethyl terephthalate with ethylene glycol, or terephthalic acid and ethylene glycol. A first-stage reaction for forming a glycol ester of terephthalic acid and / or a low polymer thereof by reacting with oxide, and then heating the product under reduced pressure to a polycondensation reaction until a desired degree of polymerization is obtained. It is easily produced by the second step reaction.

In order to copolymerize the above-mentioned one end-capped polyether with the end of the polyester chain, any stage before the completion of the above-mentioned polyester synthesis, for example, before the reaction in the first stage, during the reaction, and after the reaction is completed. After that, the reaction may be added at an arbitrary stage such as during the reaction in the second stage, and the production reaction may be completed after the addition.

If the amount of the polyether used in this case is too small, the soil release property of the polyester fiber finally obtained and its washing durability will be insufficient, and conversely if it is too large, the polyester will be used in the course of the polycondensation reaction. Since the degree of polymerization of (1) reaches a peak at a low level, the yarn physical properties such as strength of the finally obtained polyester fiber deteriorate. Also, when a large amount of polyether is included,
Since the light resistance of the obtained fiber deteriorates, it is desirable that the copolymerization amount be as small as possible. In the present invention, the copolymerization amount of polyether is 0.5 to 10 relative to polyester.
It should be in the range of% by weight, particularly preferably in the range of 2 to 5% by weight. As described above, in the present invention, the copolymerization amount of the polyether can be suppressed to a small amount, so that the obtained fiber can retain sufficient light resistance.

If desired, stabilizers, matting agents, antioxidants, optical brighteners, catalysts, anti-coloring agents, heat-resistant agents, colorants, inorganic particles and the like may be used in combination. In particular, when the polyether is left at a high temperature such as under melt spinning conditions, it is easily oxidized to easily cause a problem such as a decrease in the degree of polymerization and coloration. Therefore, it is preferable to use an antioxidant or an optical brightener together. In many cases. Further, the polyester having room temperature soil-releasing property in the present invention can be easily used together with other additional functions. For example, if an ionic antistatic agent is used together, a fiber excellent in antistatic property can be obtained. The field of application will further increase.

The degree of polymerization of the thus-obtained polyester of the present invention is preferably 0.58 or more, particularly preferably 0.6 or more in terms of intrinsic viscosity in order to exhibit sufficient fiber characteristics.

When the modified polyester is made into fibers, it is not necessary to employ a special method, and the melt spinning method of polyester fibers can be employed under arbitrary conditions. For example, a method of melt-spinning at a speed of 500 to 2500 m / min, a method of stretching and heat treatment, a method of melt-spinning at a speed of 1500 to 5000 m / min and a method of simultaneously performing drawing and false twisting, or more than 5000 m / min. Any spinning conditions such as a method of melt spinning at high speed and omitting a drawing step may be adopted depending on the application. Here, the fiber to be spun may be a solid fiber having no hollow portion or a hollow fiber having a hollow portion. Further, the outer shape of the fiber to be spun in cross section and the shape of the hollow portion may be circular or irregular.

The spun fiber exhibits a sufficient fiber performance, so that the elongation is preferably 40% or less and the strength is 4 g /
It is stretched so that it is equal to or more than de, and heat-treated if necessary.

[0026]

The reason why such an excellent low temperature antifouling effect is exhibited is not yet clear, but the hydrophilicity of the polyether, the glass transition temperature, the end group effect, and the microphase of the polyether segment in the polyester fiber. It is considered that the separation state, the interfacial affinity with the polyether segment of the polyester matrix, the decomposition elution property of the polyether segment with respect to washing water, and the like are complicatedly entangled.

[0027]

EFFECT OF THE INVENTION The polyester fiber of the present invention exhibits its characteristics particularly when it is used for clothes such as uniforms which are frequently washed, and is subjected to severely repeated washing treatment,
In particular, it exhibits excellent durability and antifouling properties even when it is washed with low-temperature water of 20 ° C. or lower. Therefore, the polyester fiber of the present invention is extremely useful in the field of textile uniforms. In addition, application to the linen supply field is also effective.

Further, the polyester fiber of the present invention is used, if necessary, in a mixed spinning with a natural fiber such as cotton and wool, a recycled fiber such as rayon and acetate, and a synthetic fiber other than the polyester of the present invention, a mixed weave and the like.

[0029]

EXAMPLES The present invention will be further described with reference to the following examples. Parts and% in the examples represent parts by weight and% by weight, respectively. The intrinsic viscosity [η] of the polymer was found to be 0.62 to 0.70 in all the examples as a result of the value measured from the orthochlorophenol solution at 35 ° C.

In the examples, the following methods were adopted for washing treatment, stain treatment, and determining the stain rate.

(1) Washing treatment Water having a liquid temperature of 10 ° C. was placed in a domestic washing machine, and 2 g of synthetic detergent for clothes was added to and dissolved in 1 liter of water to prepare a washing liquid. The sample and the load cloth were put into this washing liquid so that the bath ratio became 1:30, and the operation was started. 5
After treatment for 0 minutes, the operation was stopped, the sample and the load cloth were dehydrated by a dehydrator, and then overflow water washing was performed for 15 minutes to dehydrate. The above washing was performed as LL5 and this was repeated as many times as necessary.

(2) Contamination treatment 10 cm × sandwiched in a holder with an artificial dirt liquid of the following composition
A 13 cm woven fabric was dipped to give stains. Artificial dirt liquid ・ Motor oil 99.335 wt% (Dia Queen Motor Oil M-2) made by Mitsubishi Motors Corporation ・ C heavy oil 0.634 wt% ・ Carbon black 0.031 wt% After that, put the sample between filter papers Remove the contaminated liquid of
It was allowed to stand in a dryer at 80 ° C. for 8 hours. The stain-treated sample was washed for 20 minutes in 15 ° C. water containing 2 g / l of Marcel soap under a weak condition of a home washing machine. Then, the soil release property was evaluated by the following method.

(3) Evaluation of Soil Release Property Using a Minolta color difference meter CR-200 (Minolta Camera Sales Co., Ltd.), the sample CIE colorimeter ΔE was measured by a conventional method.
^* Was obtained and the soil release property was calculated by the following formula.

[0034]

[Equation 1]

In the above formula, ΔE ^* : Soil release property L ₁ , a ₁ , b ₁ : E ^* (L ^* , a ^* , of the sample before contamination)
_{^{b *) L 2, a 2}} , b 2: E of the sample after washing ^* (L ^*, a ^*,
b ^* )

[0036]

Example 1 100 parts of dimethyl terephthalate, 60 parts of ethylene glycol, 0.06 part of calcium acetate monohydrate (0.066 mol% with respect to dimethyl terephthalate) and cobalt acetate tetrahydrate as a color-matching agent. 009 parts (0.007 mol% with respect to dimethyl terephthalate) was charged into a transesterification reaction vessel, and this reaction product was heated from 140 ° C. to 220 ° C. over 4 hours under a nitrogen gas atmosphere, and then charged into the reaction vessel. A transesterification reaction was performed while distilling off the produced methanol to the outside of the system. After the completion of the transesterification reaction, 0.058 part of trimethyl phosphate (0.080 mol% based on dimethyl terephthalate) as a stabilizer and 0.024 part of dimethylpolysiloxane as an antifoaming agent were added to the reaction mixture.
Next, 10 minutes later, 0.04 parts of antimony trioxide (0.027 mol% with respect to dimethyl terephthalate) was added to the reaction mixture, and at the same time, while excess ethylene glycol was distilled off, the temperature was raised to 240 ° C., Then, the reaction finished product was transferred to a polymerization reaction can. Next, the reaction mixture was added to the following chemical formula:

[0037]

[Chemical 3]

4 parts of polyether having an average molecular weight of 2570 represented by (m is 53) is added, the pressure in the reaction vessel is reduced from 760 mmHg to 1 mmHg over 1 hour, and at the same time, the temperature of the reaction mixture is adjusted. 240 ° C to 285
The temperature was raised to ° C. Polymerize further under reduced pressure of 1 mmHg,
At this stage, Sumilizer GA-80 (manufactured by Sumitomo Chemical Co., Ltd.) and ADEKA STAB AO-412S (manufactured by Asahi Denka Co., Ltd.) were used as antioxidants in the reaction mixture at 0.2 parts each.
It was added in portions and then polymerized until the melt viscosity of the system reached a predetermined value. The obtained polymer was made into chips by a conventional method.

After drying the obtained chips by a conventional method,
Melt at 285 ° C using an extrusion spinning machine having a spinneret with 24 circular spinning holes with a hole diameter of 0.3 mm, and discharge amount 3
The unstretched yarn obtained by spinning at 7.5 g / min and a take-up speed of 1500 m / min was subjected to a stretching treatment machine having a heating roller at 80 ° C. and a plate heater at 160 ° C., and the elongation was 30%. Stretch heat treatment is performed at a stretch ratio such that
A drawn yarn of 5 denier / 24 filament was obtained.

A knitted fabric is manufactured using the drawn yarn obtained, and the knitted fabric is scoured and preset (180 ° C x
1 minute) to obtain a knitted fabric. This was subjected to the above-mentioned stain treatment, and the stain removability was evaluated.

The results are shown in FIG.

[0042]

Examples 2 to 7 The same operation as in Example 1 was performed. However, as a polyether, the following chemical formula (II)

[0043]

[Chemical 4]

The polyethers shown in Table 1 were used.

The results are shown in FIG.

[0046]

Comparative Examples 1 to 4 The same operation as in Example 1 was performed. However, instead of the polyether, the polyoxyalkylene-based polyether shown in the above chemical formula (II) and Table 1 was used.

For Comparative Example 2, the following chemical formula (II
I)

[0048]

[Chemical 5]

The polyether represented by was used.

The results are shown in FIG.

[0051]

[Table 1]

[Brief description of drawings]

FIG. 1 shows soil release properties when washed with a washing liquid at 10 ° C.

Claims (1)

[Claims] 1. A polymer represented by the following general formula (I): embedded image in at least a part of a polyester terminal containing ethylene terephthalate as a main constituent unit. (In the formula, M is a hydrogen atom, a monovalent metal or a quaternary phosphonium salt. R is the same or different and has 1 to 20 carbon atoms.
Hydrocarbon group of at least one of which has 6 carbon atoms
The above hydrocarbon groups. p is an integer of 1 to 5, q is 1
It is an integer of 5 and p + q ≦ 5. m is 15 to 1
It is an integer of 20. ), Which is a polyester obtained by copolymerizing a polyoxyalkylene-based polyether having a molecular weight of 6000 or less, wherein the copolymerization amount is 0.5 to 10% by weight with respect to the matrix polyester, and improved room temperature soil release Polyester fiber with properties.