JPS60110980A - Production of polyester fiber for reinforcing rubber - 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 efficiently producing polyester fibers that have excellent adhesion to rubber.

Polyester fibers, typified by polyethylene terephthalate, have excellent properties such as tensile strength and dimensional stability, and are particularly suitable as rubber reinforcing materials for power transmission belts, belts, automobile tires, hoses, and the like. However, since polynisdel $AIi# has poor adhesion to rubber, rubber materials reinforced with polyester fibers often separate at the interface between the fibers and the rubber during use, resulting in a problem that the durability of the reinforcing effect is short.

Various proposals have been made to improve the adhesion of polyester fibers to rubber. Among them, a typical method is to first treat polyester fibers with a first treatment bath containing an isocyanate compound, and then RF treatment.
It is a two-bath processing method consisting of processing in a second processing bath containing a resorcinol-formaldehyde-rubber latex mixture designated as L. Although the polyester fiber obtained by this two-bath treatment method shows relatively excellent adhesion to rubber, there is still room for improvement, so we set the goal of further improving the adhesion. A method of treating with a spinning oil containing an epoxy compound followed by a resorcinol-formaldehyde rubber latex treatment (Japanese Unexamined Patent Publication No. 48-2701
7 and JP-A-52-18921) and (2) a method of blending an epoxy compound into the first treatment bath of the two-bath treatment method (Japanese Patent Publication No. 42-11482). According to the use of this epoxy compound,
The number of functional groups on the surface of the polynisder fiber increases, which certainly improves the adhesion to rubber, but in the case of method (1) above, an epoxy compound is added and IC4A! When the i-string is hot-stretched in the drawing process, the high-temperature heating plate and Boh roller become contaminated, resulting in thread breakage and deterioration of Ab thread quality. There is. In addition, in method (2) above, there is no problem with stretching and kneading as in method (1) above, but since the amount of application is inevitably large, smoke is also generated in the heat treatment process after treatment, and furthermore, advanced rubber The disadvantage is that adhesive properties cannot be obtained with.

Therefore, the use of epoxy compounds is not preferred, and it is a major challenge to reduce the amount of epoxy compounds used as much as possible, and to obtain t'3 and excellent adhesion to rubber. Generally, when polyester fibers are melt-spun and drawn, it is essential to apply a spinning oil to the alim prior to drawing. Since this tends to impair the adhesion effect of the enclosing agent that is subsequently used, some proposals have been made to select a specific spinning oil. It has not reached the point where it has a high degree of adhesiveness.

Therefore, the present inventors conducted intensive studies with the aim of efficiently producing lζ polyester fibers with poor adhesion to rubber, and found that polyester m fibers were first treated with a specific spinning oil; By applying the above-mentioned two-bath treatment method to the rubber, there is no yarn breakage, deterioration of yarn quality, or smoke generation during the drawing process, and the rubber has a high degree of rubber adhesion that is particularly suitable for power transmission bells. It was discovered that a reinforcing polynisder fiber can be obtained, and the present invention was developed.

Specifically, the present invention provides polyester fibers including A, (a) at least one selected from ethylene oxide and/or propylene oxide adducts of aliphatic amines having 8 to 22 carbon atoms, and (b) polyhydric alcohols and polyhydric alcohols. Contains at least one type J5 selected from ethylene oxide and/or propylene oxide adducts and (G) dimethylbolysiloxane, (a), (b) and (C)
In one copy of iL 100ffiff (a > 40 ~
80 parts by weight, (b) is 10 to 50 parts by weight, <c> is 0
．． After treatment with a spinning oil in an amount of 5 to 10 parts by weight, B. treatment with a treatment bath containing an isocyanate compound, and then C. treatment with a treatment bath containing a resorcinol-bormaldehyde-rubber latex mixture. The present invention provides a method for producing polyester fibers for rubber reinforcement, which is characterized by the following.

As mentioned above, the treatment process of the present invention includes three steps: Δ, spinning oil application step, B, isocyanate compound treatment step (first treatment bath), and C, RFL treatment step (second bath). Although broadly classified, the polynisdel fiber subjected to the above process is a spun yarn immediately after melt spinning or an undrawn yarn made by winding it once, and the polyester aliN subjected to the above process B and C is a yarn that has undergone the above process. Then, it is stretched to form lanes or cords or woven fabrics made of these yarns. It is also possible, of course, to process the AI-n in step B, and then to process it in step C after passing through a cord or weaving process.

In step A of the present invention, (a) at least one selected from ethylene oxide and/or propylene oxide adducts of aliphatic amines having 8 to 22 carbon atoms;
) Polyhydric alcohol and polyhydric alcohol ethylene oxide and/or IC are selected from propylene oxide adducts, and it is essential to use a spinning oil containing at least one type of IC and (C) dimethylborisiloxane in a specific proportion. .

Here, the above (a) ethylene oxide and/or propylene oxide of an aliphatic amine having 8 to 22 carbon atoms (
The q-adduct has the following general formula (' IS dashi formula, where R is a saturated or unsaturated alkyl group or alkylene group having 8 to 22 carbon atoms, and X is O or 2
, y is 0 or 3, ns IIIM D iJ3 and q
is a tertiary amine represented by (an integer from 1 to 50), and specific examples include the following.

+11+l+=5~50゜n +m -1-11+q =6~50゜+11+n=
10-50, m tenn = 6-50, n -+-m +p ten (+ = 6-50 J5(a
) Among the components, ethylene oxide (q-adduct) of aliphatic amine having 12 to 18 carbon atoms is particularly preferably used.

Further, specific examples of the above component (b) include glycerin, diglycerin, monoalkylglycerin, dialkylglycerin, trialkylglycerin, polyglycerin, trimethylolethane, ]-limethylolpropane, 1.2
．． 3. Polyhydric alcohols such as -pentatriol, erythrol, pentaerythritol, adonyl, xylyl, sorbitol, and mannitol, and ethylene oxide and/or of these polyhydric alcohols.
Or a propylene oxide adduct. The ethylene oxide and/or propylene oxide usually has 2 to 60 repeating units, particularly 5 to 45 repeating units, and the optimum number of moles added to the polyhydric alcohol is usually 10 to 40. Among the components (1)), ethylene oxide adducts of di- or polyglycerin are particularly preferably used.

(C) As the dimedylbolysiloxane (silicone oil), it is appropriate to use one with a viscosity of 50 mm or less, and depending on the case, it may be modified with a body acid group, a carboxyl group, an epoxy group, a phenol group, etc. You can also use silicone oil. Among component (C), it is particularly preferable to use an emulsion silicone oil having a diameter of 5 to 40 cm.

(a), (b) in the spinning oil used in the above process
) The ratio of # and (C) is (a) 4.0 to 80 parts by weight,
Especially 50 to 70 parts by weight, (b) 10 to 50 parts, especially 10 to 40 parts by weight (C) 0.5 to 10 parts by weight, especially 2 to 6 parts by weight (total 100 parts by weight) (+1
) If the amount of the component is too large, the adhesion property is deteriorated and thread breakage during stretching increases, which is undesirable. Also, the ratio of component (C) is 0.
If it is less than 5 parts by weight, thread breakage during stretching increases, and if it exceeds 10 parts by weight, the adhesion of the treated polyester fiber to rubber decreases, which is not preferable.

The above-mentioned spinning oil can be used in either a water-containing or non-water-containing form, and when it is water-containing, the solid content concentration is 15-255-25%. The spinning oil has three essential components (a) to (C), but if the amount is 30 parts by weight or less, it may contain compounds generally called smoothing agents, such as mineral oil and dibasic acid monomers. Alternatively, diesters and fatty acid esters of polyhydric alcohols can be contained.

Furthermore, an epoxy compound may be included as long as it does not cause staining of the hot plate, stretching rolls, etc. or generation of smoke during stretching. Other additives such as emulsifiers, static electricity generation preventive agents, and extreme pressure improvers can be added to the above spinning oil to the extent that they do not reduce adhesiveness, but components other than components (a) to (C) A proportion of 40 or less of the total amount is appropriate.

The treatment with a spinning oil agent in the Δ step (J) means an operation in which the polyester fiber cloth and the treatment agent come into contact with each other, and this also applies to the following steps 8 and C. Therefore, the treatment with a spinning oil agent in the step This is carried out by immersing the m-fiber in a spinning oil at any stage after melt-spinning, or by applying the spinning oil to the fiber for 1 degree using a roller or the like.

The above process can be carried out extremely efficiently without yarn breakage or smoke generation during heating and stretching. Moreover, the polyester 11 obtained by the adhesive treatment in the subsequent steps B and C is
- The adhesion to rubber is significantly improved compared to polyester fiber obtained by the same adhesive treatment using a spinning oil other than the spinning oil consisting of components (a) to (C). .

Next, the B and C steps which are performed on the polyester fibers drawn after the A step will be explained.

First, in step B, polyester fibers are treated in a first treatment bath containing an isocyanate compound. The isocyanate compounds used here include! [For example, polyisocyanates such as tolylene diisocyanate, metaphenylene diisocyanate, diphenylmethane diisocyanate, polymethylene polyphenylisocyanate, hexamethylene diisocyanate 1 to triphenylmethane triisocyanate, and these polyisocyanates as a blocking agent, For example, blocked isocyanates are added with phenols such as phenol, cresol, and resorcinol, oximes such as caprolactam, acetoxime, and methyl ethyl ketone oxime, alcohols such as t-butanol and t-pentanol, and ethyleneimine. .

This first treatment bath contains an isocyanate compound as an essential component, but may also contain small proportions of otsu rubber latex, epoxy compounds, carbon black, R, FL, etc. The concentration of the first treatment bath is 1 to 30% by weight.
It is particularly preferable to adjust the amount to 5 to 15% by weight.

Next, in step C, the polyester fibers are treated in a second treatment bath using RFL. RFL used here refers to the initial synthesis of resorcinol/formaldehyde obtained from water, resorcinol, bormnoldide, and caustic soda, and this synthesis was added to rubber latex to form a resorcinol/formaldehyde/rubber latex mixture. It is something. Note that instead of the above-mentioned caustic soda, 7 ammonia may be used as the condensation catalyst.

Examples of the rubber latex include natural rubber latex, styrene-butadiene copolymer rubber latex, chloroprene rubber latex, styrene-butadiene-vinyl pyridine copolymer rubber latex, and di-1-lyl rubber latex. J5 This second treatment bath is R
Although FL is an essential component, small proportions of other blocked isocyanate compounds, epoxy compounds, and carbon black can be added, and the solid content concentration is 1 to 30 mm%.
In particular, it is desirable to prepare and use an aqueous solution containing 5 to 20% by weight.

To apply the first treatment bath to the polyester fibers in step B and the second treatment bath to the polyester fibers in step C, any method such as immersion in a liquid bath or spraying from a nozzle can be used. The amount of solid content deposited on the polyester fiber is 0.5 to 10.0% by weight as the first treatment bath composition, particularly 1.0 to 5.0% by weight, and 1.0 to 1.0% as the second treatment bath composition. 10.0mrJ1%1. ! :<1. :
2. A range of 0 to 6.0% by weight is suitable. Here, if the amount of solid content attached is too small, the adhesive force will decrease, and if it is too large, the solid content will increase and the process passability will be deteriorated, which is not preferable. In order to control the solid content of the polyester fibers, methods such as squeezing with a pressure roller, blowing with air, and suction may be used.

In step B of the present invention, polyester fibers are treated with a first treatment bath, and after IC, dried at a temperature of 120 to 250°C,
Next, heat treatment is carried out at a temperature of 160 to 250°C, especially 180 to 230°C.
After treatment in the treatment bath, drying at a temperature of 100-250°C, followed by pre-treatment 3! at a temperature of 200-260°C, especially 210-250°C! l! It is desirable to If the heat treatment temperature is too low, the adhesion to the rubber will be insufficient, and if the heat treatment temperature is too high, the polyE sprue fibers will melt, resulting in a significant decrease in strength, which is not preferred.

The polyester fibers thus treated by the method of the present invention have general properties such as excellent tensile strength and dimensional stability for rubber reinforcement, have good moldability and excellent fatigue resistance, and are compoundable. Ship buried in rubber III! The adhesion between the polyester fiber and the rubber was extremely good when subjected to a peel adhesion test after peeling, and this can be said to be a high level of performance that particularly meets the performance requirements of power transmission belts.

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

Examples 1 to 7 and Comparative Examples 1 to 7 A polyethylene phthalate filament yarn of 1500 denier and 288 filaments was melt-spun using a conventional method, and the spinning oil shown in Table 1 was applied to the yarn using an oiling roller.
After applying the film, it was stretched at 250°C at a stretching ratio of 5.5 times using a hot roller, and the stretchability at this time was evaluated. The amount of oil applied to the obtained yarn is 0.9 weight ff1
%Met.

The stretchability was evaluated by the number of thread breakages that occurred during stretching of 1 ton of polyethylene terephthalate filament with a weight of s#in.

Next, an untreated cord of 1500/2/3, a number of first twists of 30 T/iQcm, and a number of final twists of 20 T/cm was obtained from the above polyethylene terephthalate filament 1-system, and this was mixed with an isocyanate compound (manufactured by Nippon Polyurethane Co., Ltd., "Millionate"). MR200'') and toluene (Kataniku Kagaku Kogyo Co., Ltd. reagent grade 1) were mixed in a dipping liquid of the first treatment bath in a ratio of 10/90, and then after drying,
Pretreatment PI at °C! L/ta.

Meanwhile, water 2930, resorcinol 13g1 formalin 14
9. Blend 13 g of strength soda and age for about 2 hours while stirring, then blend 182 g of neoprene rubber latex (Neobrene 650'' manufactured by Showa Neoprene Co., Ltd.), stir evenly, and age for another 24 hours. A second treatment bath was prepared.Next, the first treatment bath treatment cord was passed through this second treatment bath, and after drying, heat treatment was performed at 230°C to obtain a treatment cord.In this way, (q treatment In the cord, the solid content of the first treatment bath was 5.0% by weight, and the solid content of the second treatment bath was 6.0% by weight, each of which was attached to the fibers.

Next, the above-mentioned treated cord was embedded in chloroprene rubber, and the reinforced rubber material obtained by heating and vulcanizing at 150°C for 30 minutes was subjected to CRA method (the treated cord embedded in the rubber was peeled off from the rubber using Tensilon). Adhesiveness was evaluated by (measurement). The results are also shown in Table-1.

As is clear from the results in Table 1, the rubber reinforcing polyester IMM prepared by the method of the present invention has significantly improved adhesion to rubber, and has lζ performance suitable for power transmission belt applications. There is. On the other hand, when no silicone oil is added, there are many thread breakages during stretching (Comparative Example 2), and when a large amount of silicone oil is added to cover the stretchability, the adhesion to the rubber decreases (Comparative Example 2). 3)
. Furthermore, adhesion cannot be improved even when other common emulsifiers are used as components (a) J3 and (b) (Comparative Examples 4 and 6).

Examples 6 to 9 a3 and Comparative Examples 6 to 8 Polyethylene prephthalate filament yarn of 100 denier and 192 filaments was melt-spun in a conventional manner, and the spinning oil shown in Table 2 was applied to it using an A-iling roller. Thereafter, the film was stretched at 220° C. using a hot roller at a stretching ratio of 5.4 times. The amount of oil agent A11 was 0.7% by weight with respect to the obtained yarn.

Hereinafter, the first treatment bath and the second treatment bath were applied in the same manner as in Examples 1 to 7, and the adhesiveness of the obtained treated cords to rubber was evaluated. These results are also shown in Table-2.

As is clear from the results in Table 2, the method of the present invention
Even if the spinning oil contains other components within a permissible range, a treated cord having excellent adhesiveness that can be used satisfactorily for power transmission belts can be obtained. On the other hand, when a normal smoothing agent is used in a large amount to the extent that it is contained in a general spinning oil (
Comparative Examples 8 to 10) have low adhesion to rubber and are undesirable.

Claims (1)

[Scope of Claims] Polynisder fiber is Δ, (a> ethylene oxide and/or propylene' of aliphatic amine having 8 to 22 carbon atoms)
;A4 Niside f = at least one selected from J additives;
(l)) contains at least b1 species a3 selected from polyhydric alcohols and ethylene oxide and/or propylene A oxide fq adducts of polyhydric alcohols; l)) and (C)
If Kt100i1 [in part (a) b<40~80
f12full, (b) lfi 10 to '50 parts by weight, treated with a spinning oil in which (C) accounts for 0.5 to 10 parts by weight, and then treated with a treatment bath containing B, an isocyanate compound, Then C. 1. A method for producing polyester fibers for rubber reinforcement, which comprises treating with a treatment bath containing a resorcinol-formaldehyde-rubber latex mixture.