JP2003219903A - Polyacetal resin made fastener - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyacetal resin fastener in which cracking characteristics occurring by impacts of a sewing-machine needle or the like in sewing is improved. <P>SOLUTION: This is the fastener having an entanglement row of teeth 4, top/bottom stopping fixtures 1, 5, and a box body insertion part 7 consisting of a polyacetal resin copolymer having a melting point from 150°C to 163°C. This polyacetal resin is a polyoxymethylene copolymer obtained by carrying out terminal stabilizing treatment of an oxymethylene-oxyalkylene polymer containing 0.1 to 20 wt.% of an oxyalkylene unit of carbon number 2 to 8, produced from cyclic oligomer of formaldehyde trimer (trioxane) or formaldehyde tetramer (tetraoxane) or the like and cyclic formal or the like of the cyclic oligomer raw material, ethylene oxide, propylene oxide, epichlorohydrin, 1,3-dioxolane, 1,4-butanediol, formal of glycol and formal of diglycol or the like added of a hindered phenol series antioxidant 10 to 500 ppm. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fastener having a meshing tooth row, upper and lower stoppers, and a box accommodating portion made of a polyacetal resin copolymer having a temperature of 150 ° C to 163 ° C.

[0002]

2. Description of the Related Art Polyacetal resin is a material with excellent slidability, high rigidity / high strength, chemical resistance, and creep resistance, and is widely used in various mechanical parts such as automobiles, electric / electronic parts, and clothing. Has been done. The reason why polyacetal resins are used for clothing is that they are excellent in solvent resistance (dry cleaning resistance) such as perchlorethylene, cyclic fatigue characteristics, and slidability. Specifically, buckles and fasteners are used. And used for its sliders and buttons.

However, since the polyacetal resin is a highly crystalline resin, it lacks in toughness as compared with the polyamide resin, and when sewing a fastener having a meshing tooth row and the like to a cloth, the sewing machine needle is made of the polyacetal resin. The upper and lower stoppers and the box insertion part will be cracked. Further, since many of the upper and lower stoppers made of polyacetal resin and the box insertion portion are made of a material colored with a pigment or the like, the toughness is further lowered and the crack is aggravated. Therefore, the main body of the fastener (dental teeth)
Is a polyacetal resin, and the upper and lower stoppers against which the sewing machine needle hits and the box insertion portion are made of a polyamide resin having a toughness superior to that of the polyacetal resin. From the market, simplification of the forming process and the attaching process of the meshing tooth row and the upper and lower stoppers is strongly desired.

[0004]

If the toughness of the polyacetal resin can be improved, the cracking property at the time of sewing the cloth can be improved,
Furthermore, the fastener body (the meshing tooth row), the upper and lower stoppers, and the box body insertion portion can be integrally molded, and the process can be simplified. The present invention provides a polyacetal resin fastener in which these problems are improved.

[0005]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the inventors have found that a polyacetal resin copolymer having a melting point of 150 to 163 ° C. is effective, and arrived at the present invention. That is, the present invention is a fastener having a meshing tooth row made of a polyacetal resin copolymer having a melting point of 150 ° C to 163 ° C, an upper and lower stopper, and a box insertion portion,
Is.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The polyacetal resin referred to in the present invention means a cyclic oligomer such as formaldehyde trimer (trioxane) or tetramer (tetraoxane), the above raw materials and a hindered phenolic antioxidant in an amount of 10 to 5
Ethylene oxide, propylene oxide, epichlorohydrin, 1.3-dioxolane added at 00 ppm,
0.1-butanediol, 0.1 to 2 units of oxyalkylene units having 2 to 8 carbon atoms produced from cyclic formal such as glycol formal or diglycol formal
It is a polyoxymethylene copolymer obtained by subjecting an oxymethylene-oxyalkylene copolymer containing 20% by weight to a terminal stabilization treatment.

The molecule may have not only a linear structure but also a branched structure or a crosslinked structure. The molecular weight of the polyacetal resin is not particularly limited, but a polyacetal resin copolymer having a melt flow rate (MFR) of 5 to 45 g / 10 min is preferable from the viewpoint of moldability. Among the above polyacetal resins, 1.3-
A polyacetal resin copolymer containing dioxolane as a comonomer component is preferable, and 1-3-dioxolane is contained in an amount of 3 to 3.
Copolymerization of 20% by weight is preferable because it is easy to adjust the melting point to a desired range, has excellent cracking property when sewing with a sewing machine, and is capable of integrally forming the engaging tooth row, the upper and lower stoppers, and the box insertion portion.

The melting point of the polyacetal resin referred to in the present invention can be measured by using a differential scanning calorimeter (DSC). Specifically, the polyacetal resin is added from room temperature to 20
Incubate at 0 ° C for 2 minutes. Then, the temperature is lowered to 130 ° C. at a rate of 10 ° C./min. When the temperature is further raised at a rate of 2.5 ° C./min, an endothermic peak is detected. The peak top of the detected endothermic peak was defined as the melting point in the present invention. The polyacetal resin copolymer of the present invention has a temperature of 150 ° C to 1 ° C.
It is necessary to have a melting point of 63 ° C. When the melting point of the polyacetal resin is higher than 163 ° C, the toughness is low,
When the temperature is lower than 0 ° C, the strength is lowered, and the effect aimed at by the present invention cannot be obtained.

The polyacetal resin copolymer fastener of the present invention includes a separable bottom end stop, and is not particularly limited. Metals such as zinc die cast and aluminum die cast which have been conventionally used, and ordinary polyacetal resin are used. Alternatively, it can be applied to any fastener manufactured from a reinforced polyacetal resin or a thermoplastic resin.
In the polyacetal resin fastener of the present invention, conventionally known additives such as an antioxidant, a flame retardant, a release agent, an antistatic agent, a colorant, a lubricant, within a range that does not impair the effect thereof.
Lubricants, plasticizers, heat stabilizers, weathering agents, rust inhibitors, nucleating agents such as boron nitride and talc, glass fibers and glass beads, potassium whisker titanate, welllastonite, reinforcing agents such as calcium carbonate, pigments, etc. It is possible to use a polyacetal resin material containing a compound that has been conventionally added to a polyacetal resin.

Specifically, octadecyl-3- (3,5
-Di-t-butyl-4-hydroxyphenyl) propionate, 1,6-hexanediol-bis [3- (3,3
5-di-t-butyl-4-hydroxyphenyl) propionate], pentaerythrityl-tetrakis [3-
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionate] or triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate] or the like, a compound containing formaldehyde-reactive nitrogen or a polymer thereof, an alkali metal Or alkaline earth metal hydroxide,
Examples of the heat stabilizers include inorganic acid salts and carboxylates.

Examples of the compound containing formaldehyde-reactive nitrogen or a polymer thereof include amino-substituted triazines and co-condensates of amino-substituted triazines with formaldehyde,
Polyamide resin, acrylamide and its derivatives, or polymers obtained by polymerizing acrylamide and its derivatives with other vinyl monomers in the presence of metal alcoholate, acrylamide and its derivatives, or acrylamide and its derivatives and other vinyl monomers. Polymers obtained by polymerizing in the presence of radical polymerization, polymers containing nitrogen groups such as amines, amides, urea and urethanes can be mentioned.

Examples of amino-substituted triazines include:
Guanamine (2,4-diamino-sym-triazine), melamine (2,4,6-triamino-sym-triazine), N-butylmelamine, N-phenylmelamine, N, N-diphenylmelamine, N, N-diallyl Melamine, N, N ', N "-triphenylmelamine, N-methylolmelamine, N, N'-dimethylolmelamine, N, N', N" -trimethylolmelamine, benzoguanamine (2,4-diamino- 6-phenyl-sym-triazine), 2,4-diamino-6-
Methyl-sym-triazine, 2,4-diamino-6-
Butyl-sym-triazine, 2,4-diamino-6-
Benzyloxy-sym-triazine, 2,4-diamino-6-butoxy-sym-triazine, 2,4-diamino-6-cyclohexyl-sym-triazine,
2,4-diamino-6-chloro-sym-triazine,
2,4-diamino-6-mercapto-sym-triazine, 2,4-dioxy-6-amino-sym-triazine (amelite), 2-oxy-4,6-diamino-s
Examples include ym-triazine (amerine), N, N ′, N′-tetracyanoethylbenzoguanamine and the like.

Examples of the co-condensation product of amino-substituted triazine and formaldehyde include melamine-formaldehyde polycondensation product. Among these, dicyandiamide, melamine, and melamine-formaldehyde polycondensate are preferable. As a polyamide resin, nylon 4
-6, nylon 6, nylon 6-6, nylon 6-1
0, nylon 6-12, nylon 12, etc., and copolymers thereof, such as nylon 6 / 6-6, nylon 6 /
6-6 / 6-10, nylon 6 / 6-12 and the like.

Examples of the polymer obtained by polymerizing acrylamide and its derivative or acrylamide and its derivative and other vinyl monomer in the presence of a metal alcoholate include poly-β-alanine copolymer. These polymers are disclosed in JP-B-6-12259 and JP-B-5.
-87096, Japanese Examined Patent Publication No. 5-47568, and Japanese Patent Laid-Open No. Hei 3
It can be manufactured by the method described in each publication of No. 234729. Acrylamide and its derivatives, or polymers obtained by polymerizing acrylamide and its derivatives with other vinyl monomers in the presence of radical polymerization are disclosed in Japanese Patent Laid-Open Publication No. HEI 3/1989.
It can be manufactured by the method described in JP-A-28260.

Examples of the alkali metal or alkaline earth metal hydroxide, inorganic acid salt, carboxylate or alkoxide include hydroxides of sodium, potassium, magnesium, calcium or barium, carbonates of the above metals, and the like. Examples include phosphates, silicates, borates, and carboxylates. The carboxylic acid of the carboxylic acid salt is 10 to
These include saturated or unsaturated aliphatic carboxylic acids having 36 carbon atoms, which carboxylic acids may be substituted with hydroxyl groups. As the saturated aliphatic carboxylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, montanic acid, melissic acid,
Examples include ceroplastic acid. Unsaturated aliphatic carboxylic acids include undecylenic acid, oleic acid, elaidic acid,
Cetoleic acid, erucic acid, brassic acid, sorbin
Acid, linoleic acid, linolenic acid, arachidonic acid, propiolic acid, stearolic acid and the like can be mentioned. Further, examples of the alkoxide include methoxide and ethoxide of the above metals.

As the weather resistance (light) stabilizer, benzotriazole type substances, oxalic acid anilide type substances, and hindered amine type substances are preferable. Examples of the benzotriazole-based substance include 2- (2′-hydroxy-5′-methyl-phenyl) benzotriazole, 2- [2′-hydroxy-3,5-di-t-butyl-phenyl] benzotriazole, 2 -[2'-hydroxy-3,5-di-isoamyl-phenyl] benzotriazole, 2- [2 '
-Hydroxy-3,5-bis- (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2-
(2'-hydroxy-4'-octoxyphenyl) benzotriazole etc. are mentioned. As the oxalic acid anilide-based substance, for example, 2-ethoxy-2'-ethyl oxalic acid bisanilide, 2-ethoxy-5-
Examples thereof include t-butyl-2′-ethyl oxalic acid bisanilide and 2-ethoxy-3′-dodecyl oxalic acid bisanilide.

These substances may be used alone or in combination of two or more. As a hindered amine-based substance, 4-acetoxy-2,2,2
6,6-Tetramethylpiperidine, 4-stearoyloxy-2,2,6,6-tetramethylpiperidine, 4-
Acryloyloxy-2,2,6,6-tetramethylpiperidine, 4- (phenylacetoxy) -2,2,6
6-Tetramethylpiperidine-4-benzoyloxy-
2,2,6,6-tetramethylpiperidine, 4-methoxy-2,2,6,6-tetramethylpiperidine, 4-stearyloxy-2,2,6,6-tetramethylpiperidine, 4-cyclohexyloxy- 2,2,6,6-tetramethylpiperidine, 4-benzyloxy-2,2
6,6-Tetramethylpiperidine, 4-phenoxy-
2,2,6,6-tetramethylpiperidine, 4- (ethylcarbamoyloxy) -2,2,6,6-tetramethylpiperidine, 4- (cyclohexylcarbamoyloxy) -2,2,6,6-tetramethyl Piperidine, 4-
(Phenylcarbamoyloxy) -2,2,6,6-tetramethylpiperidine, bis (2,2,6,6-tetramethyl-4-piperidine) -carbonate, bis (2,2
2,6,6-Tetramethyl-4-piperidyl) -oxalate, bis (2,2,6,6-tetramethyl-4-)
Piperidyl) -malonate, bis (2,2,6,6-tetramethyl-4-piperidyl) -sebacate, bis (2,2,6,6-tetramethyl-4-piperidyl)-
Adipate, bis (2,2,6,6-tetramethyl-4
-Piperidyl) -terephthalate, 1,2-bis (2,2,6,6-tetramethyl-4-piperidyloxy) -ethane, α, α'-bis (2,2,6,6-tetramethyl-4) -Piperidyloxy) -p-xylene, bis (2,2,6,6-tetramethyl-4-piperidyl)
Tolylene-2,4-dicarbamate, bis (2,2,
6,6-Tetramethyl-4-piperidyl) -hexamethylene-1,6-dicarbamate, tris (2,2,6,
6-tetramethyl-4-piperidyl) -benzene-1,
3,5-tricarboxylate, tris (2,2,6,
6-tetramethyl-4-piperidyl) -benzene-1,
3,4-tricarboxylate and the like can be mentioned. The above hindered amine-based substances may be used alone or in combination of two or more.

Examples of the lubricant include long chain alcohols, low molecular weight alcohols, fatty acids, esters consisting of alcohols and fatty acids, esters consisting of aliphatic alcohols and dicarboxylic acids, polyalkylene glycols and silicon compounds. As the ester composed of dicarboxylic acid and aliphatic alcohol, dicarboxylic acid is oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid,
Suberic acid, azelaic acid, sebacic acid, undecanoic acid, brassic acid, maleic acid, fumaric acid, glutaconic acid, etc., and aliphatic alcohols are methyl alcohol, ethyl alcohol, propyl alcohol, n-butyl alcohol, isobutyl alcohol, tert. -Butyl alcohol, n-amyl alcohol, 2-pentanol, n-peptyl alcohol, n-octyl alcohol, n-nonyl alcohol, decyl alcohol, undecyl alcohol, lauryl alcohol, tridecyl alcohol, myristyl alcohol, pentadecyl alcohol , Cetyl alcohol, heptadecyl alcohol, stearyl alcohol, oleyl alcohol, nonadecyl alcohol, eicosyl alcohol, ceryl alcohol,
Behenyl alcohol, melysyl alcohol, hexyldecyl alcohol, octyldodecyl alcohol, decylmyristyl alcohol, decylstearyl alcohol,
Saturated / unsaturated alcohols such as uniline alcohol and the like, and an ester composed of both of them. These esters, whether monoesters or diesters,
Further, a small amount of unreacted aliphatic alcohol or dicarboxylic acid may be contained in the ester reaction process.

It is also possible to mix a resin other than the polyacetal resin with the polyacetal resin.
The resin that can be mixed and used is not particularly limited as long as it is compatible with the polyacetal resin, and examples thereof include polyolefin such as polyethylene and polypropylene, polystyrene, ABS resin, polyvinyl chloride, polyamide,
Polycarbonate, modified polyphenylene ether, polyethylene terephthalate, polybutylene terephthalate, polyphenylene sulfide, polyimide, polyetherimide, polyarylate, polysulfone, polyethersulfone, polyetheresterketone, liquid crystal polymer, polytetrafluoroethylene, silicon compound, thermoplastic Examples thereof include an elastomer and a polymer composed of an isocyanate compound and polyalkylene oxide.

When a mixture composition of a polyacetal resin and another resin is used, the content of the polyacetal resin is 5
It is necessary to be 0% by weight or more, and if the content of the polyacetal resin is too small, the characteristics of the polyacetal resin are impaired, which is not preferable. As the silicon compound, low density polyethylene, linear low density polyethylene, high density polyethylene, ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer, ethylene ethyl acrylate copolymer, polymethylpentene, polypropylene and Polyolefin resin such as tetrafluoroethylene-ethylene copolymer (these may contain a small amount of vinyl-based monomer such as vinyl acetate, if necessary) and poly-resin represented by the following formula [Chemical formula 1] Those obtained by graft-polymerizing a silicon compound typified by dimethylsiloxane are also included.

[0021]

[Chemical 1]

(In the formula, the methyl group is hydrogen, an alkyl group, a phenyl group, an ether group, an ester group and a reactive substituent such as a hydroxy group, an amino group, an epoxy group, a carboxyl group, a carbinol group, a methacryl group, and a mercapto group. Group, phenol group, vinyl group, aryl group, polyether group,
It may be substituted with a substituent having a fluorine-containing alkyl group or the like, and it is necessary to have a substituent having a vinyl group or an aryl group, preferably a vinyl group for grafting. In the formula, n represents an average degree of polymerization, and n = 1,0
Examples of the polyolefin include an olefin compound composed of at least one olefin unit represented by the general formula [Chemical Formula 2].

[0023]

[Chemical 2]

(R ₁ and R ₂ are selected from hydrogen, an alkyl group, a substituted alkyl group, an aryl group, a substituted aryl group and an ether group, and they may be the same or different. K = 10 to 500. ) Further, for the polyolefin, an aromatic vinyl monomer alone,
Alternatively, a polyethylene graft-modified with it and an active hydrogen-containing vinyl monomer is also included. The aromatic vinyl monomer is a vinyl monomer having a benzene ring, and includes alkyl group-substituted styrene such as styrene, methylstyrene, and ethylstyrene.

The active hydrogen-containing vinyl monomer is 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxyethyl acrylate, hydroxypropyl acrylate, 2-hydroxybutyl methacrylate, p-hydroxyphenyl methacrylate, p-hydroxybenzyl methacrylate. , Hydroxyl group-containing esters of α, β-unsaturated carboxylic acids such as glycerin monomethacrylate, polyethylene glycol methacrylate, polypropylene glycol methacrylate, acrylic acid, methacrylic acid, acrylamide, allylamine, and allyl alcohol.

The polyethylene which constitutes the above-mentioned graft modified product is an ethylene unit of 90% by weight or more, and butene-
It is polyethylene composed of 10% by weight or less of a vinyl monomer unit such as 1 or propylene. The preferred molecular weight is 2,
It is preferably in the range of 000 to 1,000,000, has a specific gravity of 0.91 to 0.98 and a melting point of 100 to 140 ° C. Specific examples thereof include polyethylene wax, low-density polyethylene, linear low-density polyethylene, high-density polyethylene, and ultra-high-molecular-weight polyethylene. Low-density polyethylene that is a homopolymer of ethylene having a number average molecular weight of 20,000. Is preferred.

The content of aromatic vinyl monomer in the graft modified product is 20 based on the total amount of the graft modified product.
~ 40% by weight. Among the graft modified products of the present invention, preferred is styrene-α on polyethylene,
Polyethylene, which is a graft polymer of a hydroxyl group-containing ester copolymer of β-unsaturated carboxylic acid and is graft-modified with the above aromatic vinyl monomer alone or with an active hydrogen-containing vinyl monomer, is added to 100 parts by weight of a polyacetal resin. On the other hand, it is used at 0.5 to 25 parts by weight.

For the polyacetal resin, it is also possible to use a polymer obtained by polymerizing an isocyanate compound, a polyalkylene oxide, and optionally a low molecular weight diol compound. The isocyanate compound referred to here is tolylene diisocyanate, xylylene diisocyanate, naphthylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, cyclohexylene diisocyanate, diisocyanate methylhexane, hexamethylene diisocyanate, triphenylmethane triisocyanate, tris. (Isocyanate phenyl) is at least one selected from cyclic trimers of thiophosphate and hexamethylene didiisocyanate.

As the polyalkylene oxide, polyethylene glycol having a polymerization degree of 4 to 1,000,
Copolymer of ethylene oxide and propylene oxide, copolymer of ethylene oxide and 1,4-butanediol, copolymer of ethylene oxide and tetramethylene glycol, polypropylene glycol, poly-
It is at least one selected from 1,4-butanediol and polytetramethylene glycol. (The copolymer may be a block copolymer or a random copolymer.) The preferred degree of polymerization is in the range of 10 to 500. The ratio of the polyethylene oxide component in the polyalkylene oxide component to the component other than polyethylene oxide is 40% by weight or more of the polyethylene oxide component,
Preferably 60% by weight or more, more preferably 80% by weight
That is all.

Low molecular weight diol compounds used as necessary are ethylene glycol, propylene glycol, 1
4-butanediol, 1.6-hexanediol, polyalkylene oxide having a degree of polymerization of less than 4 (polyethylene glycol, ethylene oxide propylene oxide copolymer, polypropylene glycol, poly-1.4-
Butanediol, polytetramethylene glycol, etc.)
It is also possible to use ethylene glycol, propylene glycol, 1.4-butanediol, 1.6
-Hexanediol is preferred.

A polymer obtained by polymerizing this isocyanate compound, polyalkylene oxide, and optionally a low molecular weight diol compound is disclosed in JP-A-6-144889.
JP-A-7-316421 and JP-A-8-316421.
It can be manufactured by the method described in JP-A-92476. Specifically, it can be obtained by reacting an isocyanate compound with a polyalkylene oxide and optionally a low molecular weight diol compound using an extruder, a kneader, a Banbury mixer or the like. This reaction may use a solvent, in which case acetone, tetrahydrofuran, dimethylformamide, dimethylsulfoxide,
It is also possible to use solvents such as dioxane, methyl ethyl ketone and toluene, organometallic compounds such as dibutyl tin laurate and dioctyl tin laurate, and urethanization catalysts such as amines such as triethylamine and diazabicycloundecene.

The molecular weight of the polymer obtained by polymerizing an isocyanate compound, a polyalkylene oxide, and optionally a low molecular weight diol compound, is 10,000 to 500 in terms of polystyrene measured by gel permeation chromatography using chloroform as a solvent. 1,000
Is preferable, and more preferably 30,000 to 30.
It is in the range of 10,000. Wollastonite, which can be added as a reinforcing material, is a natural wollastonite or synthetic wollastonite that is normally found in nature and is finely pulverized. During the process of fine pulverization, it is in the form of elongated needles or particles (short rods). Is obtained. These wollastonite may be needle-like or particle-like, or may be a combination thereof, and the particle diameter thereof is 30 μm or less in terms of volume average particle diameter. Wollastonite may be surface-treated or non-surface-treated. As the surface treatment agent, conventionally known ones can be used.

For example, various coupling agents such as silane-based, titanate-based, aluminum-based, zirconium-based can be used. Specifically, N- (2-aminoethyl)-
Examples thereof include 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, isopropyltrisstearoyl titanate, diisopropoxyammonium ethyl acetate and n-butylzirconate. The pigment includes an inorganic pigment and an organic pigment.
Inorganic pigments are those commonly used for coloring resins, for example, zinc sulfide, zinc oxide, titanium oxide, barium sulfate, titanium yellow, iron oxide, ultramarine blue, cobalt blue, flame pigment, carbonic acid. Salt, phosphate, acetate, carbon black, acetylene black, lamp black, etc., organic pigments are condensed azo, isoindoline, disazo, monoazo, anthraquinone, heterocyclic, pennon, quinacridone. System, thioindico system,
Berylene-based, dioxazine-based, and phthalocyanine-based pigments.

The present invention will be described in detail below with reference to examples. The melt flow rate described in the examples is
It measured according to ISO1133 ('97) condition D. The crackability during sewing was evaluated and judged by the following method. (1) Crackability determination: According to the following criteria. ⊚: 90% or more of the 50 flat plates did not crack. ○: 80% or more of the 50 flat plates did not crack. X: 60% or more of 50 flat plates were cracked

(2) Sewing method: 1 mm thick flat plate (15 m
m × 50 mm) and a polyester cloth were sewn with a general household sewing machine, and the crackability was evaluated. The sewing conditions are as follows. a) Sewing machine used: Monami N manufactured by Nippon Singer Co., Ltd.
EW EX1748 type b) Sewing speed: 1 cm / sec c) Fabric thickness: 1 mm d) Maximum diameter of needle used: 0.9 mmφ

[0036]

Example 1 Trioxane and sterically hindered hindered phenolic antioxidant triethylene glycol-bis-
(3- (3-t-Butyl-5-methyl-4-hydroxyphenyl) propionate) 100 ppm was added to copolymerize 1,3-dioxolane (3.5% by weight), and then unstable terminal treatment was performed. . When the melting point and melt flow rate of the obtained polyacetal resin copolymer were measured, the melting point was 163 ° C. and the melt flow rate was 30 g.
/ 10 minutes. 100 parts by weight of this polyacetal resin copolymer, 0.1 part by weight of calcium stearate, 0.3 parts by weight of triethylene glycol-bis- (3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate), nylon 0.05 parts by weight of 6/6 polymer and 0.1 parts by weight of glycerin monostearate were added, and the mixture was granulated at 200 ° C. and pelletized. After this was dried at 80 ° C. for 5 hours, a flat plate was formed by an injection molding machine and the impact cracking property at the time of sewing the fabric was evaluated. The results are shown in Table 1.

[0037]

Examples 2 to 4 and Comparative Example 1 The same operation as in Example 1 was carried out except that the amount of comonomer was changed. The results are shown in Table 1.
It was shown to.

[0038]

Example 5 The same operation as in Example 1 was performed except that the fluidity of the polyacetal resin copolymer was changed. The results are shown in Table 1.

[0039]

[Table 1]

[0040]

INDUSTRIAL APPLICABILITY The polyacetal resin fastener of the present invention has improved cracking resistance when sewing cloth. Conventionally, different resins are used for the engagement tooth row, the upper and lower stoppers, and the box body insertion portion. The present invention realizes the simplification of the molding process and the mounting process by integrating the meshing tooth row, the upper and lower stoppers, and the box insertion portion with polyacetal resin.

[Brief description of drawings]

FIG. 1 shows a schematic view of a fastener made of polyacetal resin copolymer.

FIG. 2 illustrates a box body and an insertion portion of a fastener made of a polyacetal resin copolymer.

[Explanation of symbols]

1. Top stop 2. slider 3. Fastener tape 4. Dentition 5. Lower stopper 6. Box body (receiving part) 7. Insertion part

Claims (2)

[Claims] 1. A fastener having a meshing tooth row made of a polyacetal resin copolymer having a melting point of 150 ° C. to 163 ° C., an upper and lower stopper, and a box insertion portion. 2. The fastener according to claim 1, wherein the polyacetal resin is a polyacetal resin copolymer obtained by copolymerizing 3 to 20% by weight of a comonomer component.