JP2001164472A - Fiber glue for pre-wet sizing - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To exhibit excellent embracing force even in a state where a sizing agent is adhered only near the surface layer by pre-wet sizing, the sizing film is broken by abrasion on a loom, etc. Provided is a fiber sizing agent capable of exhibiting sufficient weaving properties without using the same. A fiber sizing agent for pre-wet sizing comprising PVA substantially containing 2 to 19 mol% of an α-olefin unit having 4 or less carbon atoms in a molecule.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiber sizing agent having excellent weaving performance when weaving using various fibers. In particular, the present invention relates to an industrially useful fiber sizing agent which is suitable for a pre-wet sizing method which has been spotlighted in recent years and which can further exhibit the features obtained by the sizing method.

[0002]

2. Description of the Related Art Conventionally, polyvinyl alcohol-based polymers (hereinafter abbreviated as PVA), starches, carboxymethylcellulose, water-soluble acrylic sizing agents, etc. have been used as sizing agents for the purpose of reinforcing the warp of woven fabrics. ing. Of these, starch is a natural water-soluble polymer that has been used in warp sizing agents since the oldest, and because of its low price, it is still widely used, mainly in warp sizing agents for spun yarns. Since the size of the glue film was weak, it was necessary to increase the amount of glue adhered to the yarn with a high ratio of starch. In this respect, PVA has been used as a main component of a paste instead of starch, because it is effective as a water-soluble paste for long-term storage without decay, and the strength of the obtained film is extremely strong.

[0003]

The pre-wet (Pre-wet) sizing method, which has been receiving attention in recent years, is as follows.
This is a so-called two-stage gluing method in which the yarn is once passed through water just before gluing. The use of such a gluing method is characterized in that fluff is reduced, yarn strength is improved, and divide resistance during gluing is reduced as compared with a normal gluing method. In addition, since a wet core is present inside the yarn, the penetration of the sizing liquid into the yarn during sizing is suppressed, and the amount of the sizing liquid absorbed is reduced to reduce the amount of sizing. This is a revolutionary gluing method that can reduce the agent cost. However, unlike the conventional gluing method, there is no function that the glue penetrates into the yarn and adheres between the single fibers, and the glue coating on the surface layer of the glued yarn is destroyed by factors such as abrasion on the loom. In such a case, there is a problem that the non-conjugating raw yarn is exposed from the inside and the weaving property is reduced. The present invention has been made in view of the above circumstances to provide a fiber sizing agent that is optimal for a pre-wet sizing method.

[0004]

The present inventors have conducted intensive studies to develop a fiber sizing agent for pre-wet sizing having the above-mentioned preferable properties.
P containing from 2 to 19 mol% of the following α-olefin unit:
It has been found that the problem of the present sizing method can be solved by using a fiber sizing agent composed of VA, and the present invention has been completed.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. The PVA used for the fiber sizing agent suitable for the pre-wet sizing of the present invention is a vinyl ester and a carbon number 4
It is obtained by saponifying a copolymer with the following α-olefin unit. The method for producing PVA is not particularly limited, and a polyvinyl ester polymer obtained by polymerizing or copolymerizing a vinyl ester by a known polymerization method such as lump, solution, suspension or emulsification is saponified by a known method. Obtained by: The vinyl ester is not particularly limited, and examples thereof include vinyl formate, vinyl acetate, vinyl propionate, and vinyl pivalate, and vinyl acetate is often used.

The α-olefin unit having 4 or less carbon atoms used in the present invention is not particularly limited as long as it can be copolymerized with a vinyl ester, and examples thereof include ethylene, propylene, n-butene and isobutene. Ethylene is often used because of the availability of raw materials. The content of the α-olefin having 4 or less carbon atoms is 2 to 19 mol%.
Is essential, and preferably 2.5 to 17 mol%, more preferably 3 to 15 mol%, and particularly preferably 3.5 to 13 mol%. When the content of the α-olefin having 4 or less carbon atoms is less than 2 mol%, the effect of improving physical properties such as reduction of fluff, strong yarn strength and low divide resistance at the time of sizing is small, and exceeds 19 mol%. In such a case, the water solubility or water dispersibility is reduced, so that the desizing property of the woven fabric becomes poor, which is inappropriate. The content of the α-olefin in the α-olefin-containing PVA-based resin having 4 or less carbon atoms of the present invention is determined by proton NMR of the α-olefin-containing polyvinyl ester which is a precursor of the PVA.

The viscosity average polymerization degree (hereinafter abbreviated as polymerization degree) of PVA used for the fiber sizing agent for pre-wet sizing of the present invention is 100 to 4000, more preferably 2 to 2.
00 to 3000, more often 300 to 2500. If the degree of polymerization is less than 100, satisfactory weavability may not be obtained, probably because the strength of the obtained sized yarn is reduced. If the degree of polymerization exceeds 4000, the viscosity of the aqueous solution at the time of sizing becomes high, the workability becomes poor, and the use thereof may be restricted. The degree of polymerization (P) of PVA is
It is measured according to JIS-K6726. That is, P
It is determined from the intrinsic viscosity [η] measured in water at 30 ° C. after re-saponifiing and purifying VA according to the following equation. P = ([η] × 10 ³ /8.29) ^{(1 / 0.62)}

The degree of saponification of the vinyl ester portion of the PVA used in the fiber sizing agent for prewet sizing of the present invention is not particularly limited, but is usually 60 to 100 mol%, and more preferably 70 to 99.9 mol%. There are many. Saponification degree 6
If it is less than 0 mol%, the water solubility or water dispersibility tends to decrease, and the viscosity at the time of sizing may become unstable, or the desizing of the woven fabric may be limited.
In addition, these PVA's having different degrees of polymerization and saponification may be used.
Mixing more than seeds can be used. Furthermore, as long as the effects of the present invention are not impaired, unmodified PVA
Alternatively, it may be used by mixing with a modified PVA of another modified species.

The vinyl alcohol copolymer containing from 2 to 19 mol% of an α-olefin unit having 4 or less carbon atoms in the molecule used in the present invention is different from the above in view of water solubility or water dispersibility. It can be further modified by a modified species. The comonomer unit is not particularly limited as long as it can be copolymerized with a vinyl ester. For example, α-olefins having 5 or more carbon atoms, itaconic acid (anhydride), maleic acid (anhydride), acrylic acid, methacrylic acid acid,
Acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, trimethyl- (3-acrylamido-3-dimethylpropyl) -ammonium chloride, ethyl vinyl ether, butyl vinyl ether, N
-Vinylpyrrolidone, vinyl chloride, vinyl bromide, vinyl fluoride, vinylidene chloride, vinylidene fluoride, tetrafluoroethylene, acrylamido-2-methylpropanesulfonic acid and its sodium salt, sodium vinyl sulfonate, sodium allyl sulfonate, etc. Examples include, but are not limited to: The comonomer content is often used at 10 mol% or less. If the content of the comonomer exceeds 10 mol%, the effect of the present invention may be inhibited, and the use thereof may be restricted.

[0010] The fiber sizing agent for pre-wet sizing of the present invention is a water-soluble polymer such as starch, a water-soluble cellulose compound, a water-soluble acrylic sizing agent and a smoothing agent such as wax and oil, as long as the effect is not impaired. Other additives may include antifoaming agents, antistatic agents, preservatives, fungicides, and the like.

As the starches, raw starch or processed starch obtained by subjecting raw starch to gelatinization (gelatinization), oxidation, esterification, etherification, grafting, carboxymethylation and the like can be suitably used. As a raw material for these starches, those produced from natural grains such as corn, potato, wheat, tapioca, rice and the like can be used. Examples of the water-soluble cellulose compound include, but are not limited to, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose, and the like. Similarly, the water-soluble acrylic paste, leveling agent, and other additives can be appropriately used without any particular limitation.

[0012]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. In the following, “parts” and “%” mean “parts by weight” and “% by weight”, respectively, unless otherwise specified.

EXAMPLE 1 A copolymer comprising 4.5 mol% of ethylene units and 95.5 mol% of vinyl acetate units was saponified to give a saponification degree of the vinyl acetate units of 95.0 mol% and a polymerization degree of 150.
0 was obtained as PVA-1. A size liquid having the following formulation was prepared using PVA-1, and sized with a pre-wet type test sizer to measure the physical properties of sized yarn instead of weaving. The effects of the present invention using PVA obtained using ethylene as the following α-olefin are clear. Table 1 shows the results. (1) Glue formulation PVA-1 92 parts Wax for fiber sizing agent (Wapset 600, manufactured by Takemoto Yushi Co., Ltd.) 8 parts (2) Gluing conditions Yarn: 100% cotton yarn (Toyobo Co., Ltd. “Goldfish”) 40/1) Gluing machine: 20 test sizers Gluing device 1 box 1 sheet type However, a water tank for pre-wet is installed in front of the glue tank (pre-wet tank squeezing pressure: 50 kg / cm) Pre-wet tank and size liquid temperature : 90 ° C Glue tank squeezing roll air pressure: 2.0kg / cm ² Yarn speed: 40m / min Drying temperature: 110-120 ° C

Example 2 A test was conducted in the same manner as in Example 1 except that a size liquid having the following formulation was prepared using PVA-1. As a result, a high abrasion strength was obtained, and the α-olefin of the present invention was obtained. It is clear that PVA obtained by using ethylene as a component also has an effect when blended with fresh corn starch. Table 1 shows the results. (1) Glue formulation PVA-1 70 parts Raw corn starch 22 parts Fiber sizing wax 8 parts

Example 3 Saponification of a copolymer consisting of 5.0 mol% of ethylene units and 95.0 mol% of vinyl acetate units gave a degree of saponification of vinyl acetate units of 92.9 mol% and a degree of polymerization of 130.
0 was obtained as PVA-2. A test was conducted in the same manner as in Example 1 except that the size liquid having the following formulation was prepared using PVA-2. As a result, a high abrasion strength was obtained, and the effect of the present invention is clear. Table 1 shows the results. (1) Glue formulation PVA-2 70 parts Raw corn starch 22 parts Fiber sizing wax 8 parts

EXAMPLE 4 4.2 mol% of propylene units and 95.8 vinyl acetate units
By saponifying a copolymer consisting of a vinyl acetate unit of 90.2 mol% and a polymerization degree of 13
PVA-3 which was 00 was obtained. When a test similar to that of Example 1 was performed except that a size liquid having the following formulation was prepared using PVA-3, high wear strength was obtained. From this, the effect of the present invention obtained by using propylene as an α-olefin having 4 or less carbon atoms is apparent. Table 1 shows the results. (1) Glue formulation PVA-3 70 parts Raw corn starch 22 parts Fiber sizing wax 8 parts

Example 5 A saponification degree of a copolymer consisting of 8.5 mol% of ethylene units, 1 mol% of sodium allyl sulfonate units and 91.5 mol% of vinyl acetate units was obtained. 98.5 mol%, P having a polymerization degree of 1000
VA-4 was obtained. When a test similar to that of Example 1 was performed except that a size liquid having the following formulation was prepared using PVA-4, high wear strength was obtained. From this, carbon number 4
PV used in the present invention containing the following α-olefin
It is clear that A is effective even if it contains a sodium allyl sulfonate unit. Table 1 shows the results. (1) Glue formulation PVA-4 92 parts Fiber sizing wax 8 parts

Example 6 A test was conducted in the same manner as in Example 1 except that a size liquid having the following formulation was prepared using PVA-3 and PVA-4. As a result, high wear strength was obtained. From this, it is clear that two or more components may be mixed in the PVA used in the present invention. Table 1 shows the results. (1) Glue formulation PVA-3 46 parts PVA-4 46 parts Fiber sizing wax 8 parts

Comparative Example 1 PVA217 (manufactured by Kuraray Co., Ltd .: saponification degree: 88 mol%)
The same test as in Example 1 was conducted except that the polymerization degree was 1700), but the wear resistance was low. The results are shown in Table 2. From this, the effect of the present invention using PVA containing an α-olefin having 4 or less carbon atoms in the molecule is clear.

Comparative Example 2 A similar test was conducted except that PVA 217 was used in place of the PVA of Example 2, but the wear resistance was low. The results are shown in Table 2. From this, it is clear that even if raw corn starch is mixed, the effect of improving the wear strength cannot be obtained.

[0021]

[Table 1]

[0022]

[Table 2]

(Note) The value expressed as the amount of glue is
This value is a value measured by a method for correcting a part of fluff that has fallen off during desizing cleaning described in “Warp Gluing” (by Kaname Fukada and Teruhiko Kazumi, published by The Japan Textile Machinery Society) at pages 299-302. The wear strength was measured by a TM-type embracing force tester (manufactured by Daiei Kagaku Seiki Seisaku-Sho, Ltd.) until the load was cut at a load of 100 g / piece. The number of fluffs was measured using a fluff counter (DK-103 manufactured by Daiwabo Co., Ltd.) for 1 mm or more per 1 m.

[0024]

The fiber sizing agent for pre-wet sizing of the present invention exhibits excellent binding force even when the sizing agent adheres only to the surface layer by the same sizing method. Thereby, sufficient weaving properties can be exhibited without breaking the glue film.

Continued on the front page F term (reference) 3B154 BA05 BB02 BB12 BB32 BB76 BD04 BD17 BD18 DA22 4J100 AA02P AA03P AA04P AA05P AA06P AD02Q AG02Q AG03Q AG04Q CA04 CA31 HA08 4L033 AC12 CA12 CA29 CA69 CA70

Claims (1)

[Claims] 1. A fiber sizing agent for pre-wet sizing comprising a vinyl alcohol polymer containing 2 to 19 mol% of α-olefin units having 4 or less carbon atoms in the molecule.