JP6095970B2 - Mechanical parts made of oxymethylene resin - Google Patents

Description

  The present invention relates to a mechanical component made of oxymethylene resin.

  Oxymethylene resins have excellent mechanical properties, slidability, and moldability, and are therefore used in a wide range of applications such as mechanical parts, electrical / electronic parts, and automobile parts. Oxymethylene resins are widely used in mechanical parts such as clips and buckles because they have excellent strength and rigidity. Furthermore, in general, polyoxymethylene resin is an electrically insulating material, but in recent years, certain mechanical parts often require electrical conductivity without greatly changing the current design. In many cases, electrical conductivity is required to impart antistatic properties, electromagnetic wave shielding properties and the like.

  For mechanical parts using oxymethylene resin, for example, a resin buckle molded product made of a specific polyoxymethylene copolymer resin (for example, see Patent Document 1), a fitting hinge using polyoxymethylene resin (for example, Patent Document 2), a protector with a clip in which a clip portion is formed of a polyoxymethylene resin (for example, refer to Patent Document 3) has been proposed.

  As a method for imparting conductivity to oxymethylene resins, compounding of a conductive agent is generally performed, and in particular, compounding of conductive carbon is well known, but in order to impart effective conductivity, conductive carbon is compared. It is necessary to add as much as possible. For this reason, the surface functional group of conductive carbon may cause the stability and toughness of the oxymethylene resin to deteriorate. Furthermore, when such an oxymethylene resin composition is recycled, it may cause deterioration of physical properties and deterioration of the working environment.

  On the other hand, the oxymethylene resin composition which improved the stability of the oxymethylene resin and imparted conductivity has been proposed. As such an oxymethylene resin composition, for example, a polyoxymethylene composition containing a substituted urea (see, for example, Patent Document 4), a polyoxymethylene resin composition containing a quinoline compound having a specific structure as a thermal stabilizer ( For example, see Patent Document 5).

  There has also been proposed an oxymethylene resin composition imparted with conductivity by reducing the activity of the surface functional group by adding a third component resin to enhance the stability. Examples of such an oxymethylene resin composition include a polyoxymethylene resin composition containing a specific amount of an epoxy compound (see, for example, Patent Document 6), and a polyoxymethylene resin composition containing a specific amount of a thermoplastic polyurethane resin. Thing (for example, refer patent document 7) etc. are mentioned.

  Furthermore, a method for producing a composition has been proposed in order to enhance the dispersibility of the conductive component and not to reduce the stability during production. For example, a method for producing a conductive composition in which a masterbatch having a specific viscosity is formed and mixed (for example, see Patent Document 8), a crude polyoxymethylene polymer previously pulverized into a specific particle size, and mixed with carbon black. The manufacturing method (for example, refer patent document 9) etc. of an oxymethylene copolymer composition etc. are mentioned.

  Furthermore, proposals have also been made on the morphology of the dispersed state of the conductive component in the obtained molded article. For example, in a molding material composed of reinforcing fibers and two types of resins (A) and (B), after forming a composite of reinforcing fibers and resin (A), a molded product coated with resin (B) (for example, , See Patent Document 10) A molded product in which a sea-island structure is formed with two types of thermoplastic resins and a conductive inorganic filler is unevenly distributed on the island side which is a discontinuous phase (see, for example, Patent Document 11). Etc. are disclosed.

JP 2004-238440 A Japanese Patent Laid-Open No. 10-96362 JP 9-329274 A Special table 2010-510373 gazette JP-A-10-265646 JP 2009-269996 A JP-A-11-130934 Special table 2008-528768 gazette Japanese Patent Laid-Open No. 11-241000 JP 2002-88259 A JP-A-10-204305

  In recent years, there has been a demand for a mechanical component made of oxymethylene resin that has practically sufficient productivity, conductivity, and high durability. However, the techniques disclosed in Patent Documents 1 to 11 still have room for improvement in terms of conductivity and durability in the oxymethylene resin mechanism parts.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an oxymethylene resin-made mechanical component having good productivity, conductivity, and excellent durability. .

  The present inventors have made extensive studies to solve the above problems. As a result, a molded product containing polyoxymethylene, a predetermined stabilizer, a conductive carbon-based filler, a thermosetting resin, and a predetermined curing agent, and further obtained by pulverization and molding has a predetermined characteristic. It has been found that an oxymethylene resin-made mechanical part made of an oxymethylene resin composition can solve the above-mentioned problems, and the present invention has been completed.

That is, the present invention is as follows.
[1]
100 parts by mass of polyoxymethylene (A),
0.02 to 1.00 parts by mass of two or more kinds of stabilizers (B),
Conductive carbon black (C) 5.0-15.0 parts by mass;
0.5 to 5.0 parts by mass of thermosetting resin (D),
And two or more curing agent (E) 0.3 to 3.0 parts by weight, only contains, and
The stabilizer (B) includes an oxymethylene resin composition, which is a reactive nitrogen-containing compound, a metal salt of an inorganic acid, a metal oxide, or a metal salt of an organic acid ,
The molded product obtained by pulverizing and molding the molded product of the oxymethylene resin composition has a tensile yield strength of 45 MPa or more and a tensile breaking elongation of 10% or more.
Mechanical parts made of oxymethylene resin.
[2]
The mechanical component made of oxymethylene resin according to [1] above, wherein the polyoxymethylene (A) contains 0.3 mol or more of a comonomer unit other than oxymethylene units with respect to 100 mol of the oxymethylene units.
[3]
[1] or [1], wherein the stabilizer (B) contains 50% by mass or more of a reactive nitrogen-containing compound.
2] The mechanical component made of oxymethylene resin according to 2).
[4]
The thermosetting resin (D) comprises Epoxy resins, items [1] oxymethylene resin mechanical part according to any one of to [3].
[5]
Wherein the curing agent (E) is a basic re down of compounds containing more than 80 wt%, items [1] oxymethylene resin mechanical part according to any one of to [4].
[6]
The mechanical component made of oxymethylene resin according to any one of [1] to [5] , further including a sliding agent.

  According to the present invention, it is possible to realize a mechanical component made of oxymethylene resin having good productivity, conductivity and excellent durability.

(A), (b) is an image figure of the coupling component fixed as a position with unevenness as an example of a mechanism component. (A), (b) is an image figure of the container which fixes a lid | cover with a nail | claw part as an example of a mechanism component. (A), (b) is an image figure of the joining components fixed by operation | movement of an arm part as an example of a mechanism component. It is an image figure of the mechanism component made from oxymethylene resin used for evaluation in the Example. It is a photograph which shows the evaluation site | part of the mechanical component made from oxymethylene resin used for evaluation in the Example. It is an image figure explaining the test method of the mounting force evaluation of the oxymethylene resin mechanism components performed in the Example, and attachment / detachment evaluation. It is an image figure explaining the test method of fitting retention property evaluation of the oxymethylene resin mechanism parts performed in the Example.

  Hereinafter, a mode for carrying out the present invention (hereinafter referred to as “the present embodiment”) will be described in detail. In addition, this invention is not limited to the following embodiment, It can implement by changing variously within the range of the summary.

  Hereinafter, the oxymethylene resin mechanism part, the oxymethylene resin composition forming the oxymethylene resin mechanism part, and the manufacturing method of the oxymethylene resin mechanism part will be described in this order.

[1. Mechanical parts made of oxymethylene resin]
The mechanical component made of oxymethylene resin used in this embodiment is
100 parts by mass of polyoxymethylene (A),
0.02 to 1.00 parts by mass of two or more kinds of stabilizers (B),
Conductive carbon-based filler (C) 5.0-15.0 parts by mass;
0.5 to 5.0 parts by mass of thermosetting resin (D),
An oxymethylene resin composition containing 0.3 to 3.0 parts by mass of two or more kinds of curing agents (E),
The strength of the molded body obtained by pulverizing and molding the molded body of the oxymethylene resin composition is 45 MPa or more, and the elongation is 10% or more.

  The mechanical component made of oxymethylene resin of this embodiment has conductivity by including a conductive carbon-based filler, and is excellent in productivity and durability, so that it is used as a component that requires conductivity. Can do. In particular, it is suitable to be used as a component for suppressing the influence of static electricity generated by the movement of substances and electromagnetic waves generated by the movement of electricity on the periphery.

  For example, when static electricity is generated by the movement of a substance, the product is charged and dust or dust around the product adheres to it, or it may cause a conveyance failure when the product is conveyed. Furthermore, if the amount of charge increases and sparks are generated during discharge, it may cause unpleasant pain to the human body, and if there is a flammable liquid around it, it may cause a fire. Therefore, by using the mechanical component made of oxymethylene resin according to the present embodiment and neutralizing the product, the possibility of the above problem occurring can be significantly reduced.

  In addition, when electromagnetic waves are generated due to the movement of electricity, noise or malfunction occurs in telecommunication devices, sensors, circuits, or the like, or these devices are destroyed. Furthermore, the generation of electromagnetic waves has an adverse effect on the human body. Therefore, by using the oxymethylene resin mechanism part of the present embodiment and shielding electromagnetic waves, the possibility of the above problem occurring can be significantly reduced.

  Since the mechanical component made of oxymethylene resin according to the present embodiment is excellent in durability, it may be used in a mechanism that uses a reaction force generated by deformation of a part or the whole of the component. The parts of the mechanism using the reaction force are not particularly limited, but are, for example, joined parts and fitting parts, such as bosses, ribs, clips, buttons, holders, connectors, joints, snap fits, wheels, rollers, Examples include rollers, washers, spacers, bushes, rotors, bats, swivels, bearings, shaft holes, shafts, pulleys, and gears. All of these parts or the mechanism part may be the oxymethylene resin-made mechanism part of the present embodiment. Furthermore, the oxymethylene resin-made mechanism component of the present embodiment can be used as a component related to storage of a lid portion, a trunk portion, a bottom portion of a container, a cover, a case, a door, and the like. All of these parts or a part of fixed parts, operating parts, locking parts, etc. can be used as the mechanical parts made of oxymethylene resin of this embodiment.

  Although the image of the mechanical component made from oxymethylene resin of this embodiment is shown in FIGS. 1-3, the mechanical component made from oxymethylene resin is not restricted to these. FIGS. 1A and 1B are image diagrams of a coupling component that is fixed by aligning with unevenness as an example of a mechanical component. FIG. 1A shows the state of the component before joining, and FIG. 1B shows an image of the joined component viewed from above. Indicates. Moreover, FIG. 2 is an image figure of the container which fixes a lid | cover by moving a nail | claw part as an example of a mechanism component, (a) shows the state of the components before fixation, (b) shows the state which fixed the lid | cover. An image of the container seen from the side is shown. Further, FIG. 3 is an image diagram of a joined part that is fixed by operating an arm as an example of a mechanical part. FIG. 3A shows a state of the part before fixing, and FIG. 3B is an image of the part in the joined state. Indicates. In any part, the shaded part corresponds to the part of the mechanism using the reaction force.

[2. Oxymethylene resin composition for forming mechanical parts made of oxymethylene resin]
The oxymethylene resin composition forming the oxymethylene resin mechanism part of the present embodiment is composed of 100 parts by mass of polyoxymethylene (A) and 0.02 to 1.00 parts by mass of two or more kinds of stabilizers (B). , Conductive carbon-based filler (C) 5.0 to 15.0 parts by mass, thermosetting resin (D) 0.5 to 5.0 parts by mass, and two or more kinds of curing agents (E) 0. 3 to 3.0 parts by mass. This will be described in more detail below.

[Polyoxymethylene (A)]
The oxymethylene resin composition used in the present embodiment contains 100 parts by mass of polyoxymethylene (A). The polyoxymethylene (A) used in the present embodiment includes a polyoxymethylene homopolymer (A-1) having only an oxymethylene unit in the main chain, an oxymethylene unit in the molecule, and a comonomer unit other than the oxymethylene unit. Or a mixture of polyoxymethylene homopolymer (A-1) and polyoxymethylene copolymer (A-2). In particular, the oxymethylene resin composition used in the present embodiment preferably contains a polyoxymethylene copolymer (A-2). The polyoxymethylene homopolymer (A-1) and the polyoxymethylene copolymer (A-2) can be produced by the following polymerization process, terminal stabilization process and granulation process.

<Polyoxymethylene homopolymer (A-1)>
(1) Polymerization process The polyoxymethylene homopolymer (A-1) used in the present embodiment represents a polymer having only oxymethylene units in the main chain. Note that both ends or one end of the polyoxymethylene homopolymer (A-1) may be blocked with an ester group or an ether group. The polymerization mode in the production of the polyoxymethylene homopolymer (A-1) is carried out using a known slurry polymerization method (for example, the method described in Japanese Patent Publication Nos. 47-6420 and 47-10059). be able to. Thereby, the crude polyoxymethylene whose terminal is not stabilized can be obtained.

1) Monomer Although it does not specifically limit as a monomer used for manufacture of a polyoxymethylene homopolymer (A-1), For example, formaldehyde can be used. At this time, in order to continuously obtain a polyoxymethylene homopolymer (A-1) having a stable molecular weight, it is preferable to use a formaldehyde gas which is purified and has a low impurity concentration and is stable. As a purification method of formaldehyde, a known method (for example, a method described in Japanese Patent Publication No. 5-32374 and Japanese Patent Publication No. 2001-521916) can be used.

  The formaldehyde gas used in the present embodiment is preferably one that contains as little impurities as possible, such as water, methanol, formic acid, and the like, which has polymerization termination and chain transfer action during the polymerization reaction. The fewer these impurities, the more unexpected chain transfer reaction can be avoided, and the desired molecular weight polyoxymethylene homopolymer (A-1) can be easily obtained. Especially, it is preferable that content of water is 100 ppm or less, and it is more preferable that it is 50 ppm or less.

2) Chain transfer agent Although it does not specifically limit as a chain transfer agent used for manufacture of a polyoxymethylene homopolymer (A-1), Generally, alcohols and an acid anhydride can be used. In order to obtain a block polymer or a branched polymer containing a polyacetal homopolymer in the main chain, a polyol, a polyether polyol, or a polyether polyol / alkylene oxide may be used.

  Further, as the chain transfer agent, it is preferable to use a chain transfer agent that contains as little impurities as possible, such as water, methanol, formic acid, or the like, during polymerization reaction and chain transfer. Especially, it is preferable that content of water is 2,000 ppm or less, and it is more preferable that it is 1,000 ppm or less. As a method for obtaining these chain transfer agents with a small amount of impurities, for example, a general-purpose chain transfer agent having a water content exceeding a specified amount is obtained, and this is bubbled with dry nitrogen, and an adsorbent such as activated carbon or zeolite. And the like, and the like. The chain transfer agent used here may be used individually by 1 type, or may use 2 or more types together.

3) Polymerization catalyst Although it does not specifically limit as a polymerization catalyst used for the polymerization reaction in manufacture of a polyoxymethylene homopolymer (A-1), An onium salt type polymerization catalyst is mentioned. As the onium salt-based polymerization catalyst used in the polymerization reaction, for example, one represented by the following formula (1) can be used.
[R ₁ R ₂ R ₃ R ₄ M] ⁺ X ⁻ (1)
(In formula (1), R ₁ , R ₂ , R ₃ and R ₄ each independently represents an alkyl group, M represents an element having a lone electron pair, and X represents a nucleophilic group.)

  Among the onium salt polymerization catalysts represented by the above formula (1), quaternary ammonium salt compounds and quaternary phosphonium salt compounds are preferably used. Among these, tetramethylammonium bromide, dimethyldistearylammonium acetate, tetraethylphosphonium iodide, and tributylethylphosphonium iodide are more preferably used.

4) Reactor The polymerization reactor in the production of the polyoxymethylene homopolymer (A-1) is not particularly limited. For example, a reaction tank with a batch type stirrer, a continuous type kneader, and a twin screw type continuous extrusion. A kneader, a biaxial paddle type continuous mixer, or the like can be used. The outer peripheries of these cylinders preferably have a structure capable of heating or cooling the reaction mixture.

(2) Terminal Stabilization Step As a method for stabilizing the terminal end by blocking the end of the crude polyoxymethylene homopolymer (A-1) with an ether group, there is a method described in JP-B 63-452. In addition, as a method of stabilizing the end by blocking the end of the crude polyoxymethylene with an acetyl group, a method of using a large amount of acid anhydride described in US Pat. No. 3,459,709 in a slurry state And an acid anhydride gas described in U.S. Pat. No. 3,172,736 in the gas phase. In the present embodiment, any of the above methods can be adopted and is not particularly limited.

  The etherifying agent in the case of blocking with an ether group is not particularly limited, and examples thereof include orthoesters. Usually, aliphatic acid or aromatic acid and aliphatic alcohol, alicyclic alcohol or aromatic alcohol And orthoesters. Examples of such orthoesters include, but are not limited to, methyl or ethyl orthoformate, methyl or ethyl orthoacetate and methyl or ethyl orthobenzoate, and orthocarbonates such as ethyl orthocarbonate.

  The etherification reaction is carried out using a Lewis acid type catalyst such as p-toluenesulfonic acid, medium strength organic acids such as acetic acid and hydrobromic acid, medium strength mineral acids such as dimethyl and diethyl sulfate, etc. It may be performed by introducing 0.001 to 0.02 parts by mass with respect to parts.

  Preferred solvents used for the etherification reaction are not particularly limited, but low boiling point aliphatics such as pentane, hexane, cyclohexane and benzene; alicyclic and aromatic hydrocarbons; halogenation such as methylene chloride, chloroform and carbon tetrachloride. Examples include organic solvents such as lower aliphatic compounds.

On the other hand, when the end of the crude polyoxymethylene is blocked with an ester group, the organic acid anhydride used for esterification is not particularly limited, and examples thereof include organic acid anhydrides represented by the following formula (2).
R ₅ COOCOR ₆ (2)
(In Formula (2), R ₅ and R ₆ each independently represent an alkyl group or a phenyl group. R ₅ and R ₆ may be the same or different.)

  Among the organic acid anhydrides represented by the above formula (2), propionic anhydride, benzoic anhydride, acetic anhydride, succinic anhydride, maleic anhydride, glutaric anhydride, phthalic anhydride, and the like are preferable. Acetic anhydride is more preferred. An organic acid anhydride may be used individually by 1 type, and may use 2 or more types together.

  Moreover, in the method of performing ester group blocking in the gas phase, it is preferable to perform terminal blocking after removing the onium salt polymerization catalyst by the method described in JP-A No. 11-92542. When the onium salt polymerization catalyst in the polyoxymethylene is removed, when the terminal is blocked, the decomposition reaction of the polyoxymethylene derived from the onium salt polymerization catalyst can be avoided, and the polymer yield in the stabilization reaction is improved. And coloring of polyoxymethylene can be suppressed.

The end of the polyoxymethylene homopolymer (A-1) is preferably blocked with an ether group and / or an ester group, so that the concentration of the terminal hydroxyl group is reduced to 5 × 10 ⁻⁷ mol / g or less. It is preferable for the concentration of the terminal hydroxyl group to be 5 × 10 ⁻⁷ mol / g or less because the thermal stability is excellent and the quality of the original polyoxymethylene resin can be maintained. More preferably, the concentration of the terminal hydroxyl group is 0.5 × 10 ⁻⁷ mol / g or less, and further preferably 0.3 × 10 ⁻⁷ mol / g or less.

(3) Granulation step After the terminal stabilized polyoxymethylene homopolymer (A-1) powder is dried, it may be granulated using an extruder to improve the handleability. At this time, it is preferable to perform granulation by melt kneading while adding a known stabilizer that can be added to ordinary polyoxymethylene. In the case of performing melt kneading, it is preferable to replace the atmosphere with an inert gas or to deaerate with a single-stage or multistage vent in order to maintain the quality and working environment. The temperature at the time of melt-kneading is preferably not lower than the melting point of the polyoxymethylene homopolymer (A-1) and not higher than 250 ° C.

<Polyoxymethylene copolymer (A-2)>
The polyoxymethylene copolymer (A-2) has a comonomer unit other than the oxymethylene unit. In the polyoxymethylene copolymer (A-2), the comonomer unit is preferably contained in an amount of 0.3 mol or more, more preferably 0.4 mol or more, and more preferably 0.5 mol or more with respect to 100 mol of the oxymethylene unit. More preferably, it is more preferably 0.6 mol or more, and even more preferably 1.2 mol or more. In addition, the polyoxymethylene copolymer (A-2) preferably contains 3.0 mol or less of comonomer units, more preferably 2.0 mol or less, and even more preferably 1.5 mol or less. Mechanical parts formed using an oxymethylene resin composition containing such a polyoxymethylene copolymer (A-2) tend to be more excellent in productivity, conductivity, and durability.

The quantification of the comonomer unit can be determined by the following procedure using ¹ H-NMR method. The obtained polyoxymethylene (A) was dissolved in hexafluoroisopropanol (HFIP) so as to have a concentration of 1.5% by mass over 24 hours, and ¹ H-NMR analysis was performed using this dissolved solution. From the ratio of the integral value of the assigned peak of the methylene unit and a comonomer unit other than the oxymethylene unit (for example, oxyalkylene unit), the molar ratio of the comonomer unit (b) to 100 mol (a) of the oxymethylene unit (b / a ).

(1) Polymerization process Both ends of the polyoxymethylene copolymer (A-2) may be blocked with an ester group or an ether group. In the production of the polyoxymethylene copolymer (A-2), a known polymerization method (for example, US Pat. No. 30,273,352, US Pat. No. 3,803,094, German Patent No. 1161411, Patent method 1495228, German patent invention No. 1720358, German patent invention No. 3018898, Japanese Patent Laid-Open No. 58-98322, and Japanese Patent Laid-Open No. 7-70267) Can do. Such a polymerization step yields a crude polyoxymethylene copolymer in which the ends of the polyoxymethylene copolymer are not stabilized.

Materials such as main monomers used in the polymerization step will be described below.
1) Main monomer Although it does not specifically limit as a main monomer used for manufacture of a polyoxymethylene copolymer (A-2), Cyclic oligomers, such as formaldehyde or its trimer trioxane, or a tetramer, tetraoxane are used. Is preferred. Here, the “main monomer” in this specification refers to a monomer unit that is contained in an amount of 50% by mass or more based on the total amount of monomers.

2) Comonomer Although it does not specifically limit as a comonomer used for manufacture of a polyoxymethylene copolymer (A-2), It is preferable to use the cyclic ether compound which has a C2 or more oxyalkylene unit in a molecule | numerator.

  The cyclic ether compound is not particularly limited, and examples thereof include ethylene oxide, propylene oxide, 1,3-dioxolane, 1,3-propanediol formal, 1,4-butanediol formal, 1,5-pentanediol formal, , 6-hexanediol formal, diethylene glycol formal, 1,3,5-trioxepane, 1,3,6-trioxocane, and a mono- or di-glycidyl compound that can form a branched or crosslinked structure in the molecule One type of compound or a mixture of two or more types may be mentioned as suitable.

  When polymerizing the polyoxymethylene copolymer (A-2), a main monomer and a comonomer that do not contain impurities having a polymerization stopping action and a chain transfer action during the polymerization reaction such as water, methanol and formic acid are used as much as possible. It is preferable. By using a main monomer and a comonomer that do not contain impurities as much as possible, an unexpected chain transfer reaction can be avoided, and a polymer having a desired molecular weight can be easily obtained. In particular, the content of impurities that induce hydroxyl groups in the polymer end groups is preferably 30 ppm by mass or less, more preferably 10 ppm by mass or less, and even more preferably 3 ppm by mass or less based on the total amount of monomers.

  As a method for obtaining the desired low-impurity main monomer and comonomer, a known method (for example, for the main monomer, the method described in JP-A-3-123777 and JP-A-7-33761, comonomer Can be used as described in JP-A-49-62469 and JP-A-5-271217.

3) Chain transfer agent It is preferable to use a chain transfer agent in the polymerization step of the polyoxymethylene copolymer (A-2). Although it does not specifically limit as a chain transfer agent, For example, it is preferable to use lower aliphatic alcohols, such as a dialkyl acetal of formaldehyde and its oligomer; and methanol, ethanol, propanol, isopropanol, and butanol. The alkyl group of the dialkyl acetal is preferably a lower aliphatic alkyl group such as methyl, ethyl, propyl, isopropyl and butyl.

  In order to obtain a long chain branched polyoxymethylene, it is preferable to use polyether polyol and an alkylene oxide adduct of polyether polyol as a chain transfer agent. Moreover, as a chain transfer agent, you may use the polymer which has 1 or more types of groups selected from the group which consists of a hydroxyl group, a carboxyl group, an amino group, an ester group, and an alkoxy group. Furthermore, the said chain transfer agent may be used individually by 1 type, and may use 2 or more types. In any case, the polyoxymethylene copolymer (A-2) obtained preferably has a small number of unstable terminals.

4) Polymerization catalyst The polymerization catalyst used in the polymerization step of the polyoxymethylene copolymer (A-2) is not particularly limited, but a cationically active catalyst such as Lewis acid, proton acid, and ester or anhydride of proton acid is preferable. .

  The Lewis acid is not particularly limited, and examples thereof include boric acid, tin, titanium, phosphorus, arsenic, and antimony halides. Specific examples include boron trifluoride, tin tetrachloride, titanium tetrachloride, phosphorus pentafluoride, phosphorus pentachloride and antimony pentafluoride, and complex compounds or salts thereof.

  Specific examples of the protonic acid, its ester or anhydride are not particularly limited. For example, perchloric acid, trifluoromethanesulfonic acid, perchloric acid-tertiary butyl ester, acetyl perchlorate, and trimethyloxonium hexafluoro Examples include phosphate. Moreover, you may use together the catalyst which reduces the production | generation of the terminal formate group described in Unexamined-Japanese-Patent No. 05-05017, for example as needed. Among these, boron trifluoride, boron trifluoride hydrate, and a coordination complex compound of an organic compound containing an oxygen atom or a sulfur atom and boron trifluoride are preferable. Boron trifluoride diethyl ether, trifluoride Boron di-n-butyl ether is more preferred.

For example, when trioxane and cyclic ether and / or cyclic formal are used, the polymerization catalyst is preferably used in an amount of 1 × 10 ⁻⁶ to 1 × 10 ⁻³ mol with respect to 1 mol of the monomer, and 5 × 10 ^−6. ˜1 × 10 ⁻⁴ mol is more preferable. When the usage-amount of a polymerization catalyst is in the said range, the reaction stability at the time of superposition | polymerization and the thermal stability of the molded object obtained will improve more.

  The polymerization catalyst can be deactivated after the polymerization step by introducing the polymer into an aqueous solution or an organic solvent solution containing a catalyst neutralization deactivator and stirring in a slurry state for generally several minutes to several hours. it can.

  Although it does not specifically limit as a catalyst neutralization deactivator, For example, Amines, such as ammonia, a triethylamine, and tri-n-butylamine; Alkali metal and alkaline earth metal hydroxide; Inorganic acid salt; From organic acid salt 1 type or more selected from the group which consists of.

  In addition, a method of deactivating a polymerization catalyst by contacting a vapor such as ammonia and triethylamine with a polyoxymethylene copolymer (A-2), a mixer with at least one of hindered amines, triphenylphosphine and calcium hydroxide It is also possible to use a method of deactivating the catalyst by contacting with.

(2) Terminal stabilization step and granulation step A stable polyoxymethylene is obtained by decomposing and removing unstable terminal portions contained in the crude polymer of the polyoxymethylene copolymer (A-2) obtained by the polymerization step described above. A copolymer (A-2) can be obtained.

  The method for decomposing and removing the unstable terminal portion contained in the crude polyoxymethylene copolymer is not particularly limited. For example, a known single-screw extruder with a vent or a twin-screw extruder with a vent may be used. Examples thereof include a method in which a crude polyoxymethylene copolymer is melted to decompose and remove unstable terminal portions in the presence of a decomposition and removal agent, which will be described later, which is a basic substance.

  When performing melt-kneading for terminal stabilization, it is preferable to replace the atmosphere with an inert gas or to deaerate with a single-stage or multistage vent in order to maintain the quality and working environment. Moreover, it is preferable that the temperature at the time of melt-kneading shall be more than melting | fusing point of polyoxymethylene copolymer (A-2) and 260 degrees C or less. Furthermore, it is preferable to perform granulation by melt mixing while adding a known stabilizer that can be added to ordinary polyoxymethylene.

1) Decomposition remover Decomposition remover used for decomposing and removing the unstable terminal portion contained in the crude polymer of polyoxymethylene copolymer (A-2) includes, for example, aliphatic amines such as ammonia, triethylamine and tributylamine; water Known basic substances such as alkali metal or alkaline earth metal hydroxides such as calcium oxide; inorganic weak acid salts; and organic weak acid salts can be used.

Among the decomposition and removal agents, a method of treating a thermally unstable terminal with at least one quaternary ammonium compound represented by the following formula (3) can be suitably used.
[R ₇ R ₈ R ₉ R ₁₀ N ⁺ ] _n Y ⁿ⁻ (3)
(In formula (3), R ₇ , R ₈ , R ₉ and R ₁₀ are each independently an unsubstituted alkyl group or substituted alkyl group having 1 to 30 carbon atoms; an aryl group having 6 to 20 carbon atoms; An aralkyl group in which the unsubstituted alkyl group having 1 to 30 or the substituted alkyl group is substituted with at least one aryl group having 6 to 20 carbon atoms; the aryl group having 6 to 20 carbon atoms having 1 to 1 carbon atoms It represents one selected from the group consisting of 30 unsubstituted alkyl groups or alkylaryl groups substituted with substituted alkyl groups.
The unsubstituted alkyl group or the substituted alkyl group may be linear, branched, or cyclic.
In the above unsubstituted alkyl group, aryl group, aralkyl group, and alkylaryl group, a hydrogen atom may be substituted with a halogen.
n represents an integer of 1 to 3.
Y represents a hydroxyl group or any acid residue selected from the group consisting of carboxylic acids having 1 to 20 carbon atoms, hydrogen acids, oxo acid inorganic thioacids, and organic thioacids having 1 to 20 carbon atoms. )

  The quaternary ammonium compound is not particularly limited. For example, tetramethylammonium, tetraethylammonium, tetrapropylammonium, tetra-n-butylammonium, cetyltrimethylammonium, tetradecyltrimethylammonium, 1,6-hexamethylenebis (Trimethylammonium), decamethylene-bis- (trimethylammonium), trimethyl-3-chloro-2-hydroxypropylammonium, trimethyl (2-hydroxyethyl) ammonium, triethyl (2-hydroxyethyl) ammonium, tripropyl (2-hydroxy) Ethyl) ammonium, tri-n-butyl (2-hydroxyethyl) ammonium, trimethylbenzylammonium, triethylbenzylammonium , Tripropylbenzylammonium, tri-n-butylbenzylammonium, trimethylphenylammonium, triethylphenylammonium, trimethyl-2-oxyethylammonium, monomethyltrihydroxyethylammonium, monoethyltrihydroxyethylammonium, okdadecyltri (2-hydroxy And hydroxides such as ethyl) ammonium and tetrakis (hydroxyethyl) ammonium.

Other examples of quaternary ammonium compounds include hydrogenates other than halogenated compounds such as hydrogen azide; sulfuric acid, nitric acid, phosphoric acid, carbonic acid, boric acid, chloric acid, iodic acid, silicic acid, perchloric acid Oxo acid salts such as chlorous acid, hypochlorous acid, chlorosulfuric acid, amidosulfuric acid, disulfuric acid and tripolyphosphoric acid; thioic acid salts such as thiosulfuric acid; formic acid, acetic acid, propionic acid, butanoic acid, isobutyric acid, pentanoic acid And carboxylates such as caproic acid, caprylic acid, caprylic acid, benzoic acid and oxalic acid. Among these, hydroxide (OH ⁻ ), sulfuric acid (HSO ₄ ⁻ , SO ₄ ²⁻ ), carbonic acid (HCO ₃ ⁻ , CO ₃ ²⁻ ), boric acid (B (OH) ₄ ⁻ ), and carvone. Acid salts are preferred. Of the carboxylic acids, formic acid, acetic acid and propionic acid are more preferred. The said quaternary ammonium compound may be used individually by 1 type, and may use 2 or more types together.

The addition amount of the quaternary ammonium compound is 0.05 to 50 mass in terms of the amount of nitrogen derived from the quaternary ammonium compound represented by the following formula (α) with respect to the crude polyoxymethylene copolymer. Preference is given to ppm.
Addition amount of quaternary ammonium compound = P × 14 / Q (α)
(In the formula (α), P represents the concentration (mass ppm) of the quaternary ammonium compound relative to the crude polyoxymethylene copolymer, “14” represents the atomic weight of nitrogen, and Q represents the molecular weight of the quaternary ammonium compound. .)

  The decomposition removing agent such as a quaternary ammonium compound may be added in advance before the crude polyoxymethylene copolymer is melted, or may be added to the melted crude polyoxymethylene copolymer. In addition, as a decomposition removal agent, you may use together the quaternary ammonium compound mentioned above with ammonia, a triethylamine, and / or a boric acid compound which are well-known decomposition removal agents.

(Stabilizer (B))
The oxymethylene resin composition used in the present embodiment contains 0.02 to 1.00 parts by mass of two or more stabilizers (B) with respect to 100 parts by mass of polyoxymethylene, preferably 0.06 to 0.00. 45 parts by mass, more preferably 0.10 to 0.30 parts by mass. By being in the above range, the mechanical component made of oxymethylene resin tends to be more excellent in productivity, conductivity, and durability.

  The two or more kinds of stabilizers (B) used in the present embodiment are a mechanism such as formaldehyde remaining and formic acid generated by the modification thereof in producing an oxymethylene resin composition or an oxymethylene mechanism part. A product that adversely affects the productivity, conductivity, and durability of a component is added in order to capture or suppress the influence. Examples of such two or more stabilizers (B) include reactive nitrogen-containing compounds, metal salts of inorganic acids, metal oxides, and metal salts of organic acids. Among these, it is preferable that the stabilizer (B) contains as little impurities as acid and / or the stabilizer is a compound that hardly generates acid, and contains 50% by mass or more of such a stabilizer. A stabilizer that does not contain an acid as much as possible and / or hardly generates an acid is not particularly limited, but specifically, it is a reactive nitrogen-containing compound, such as a polyamide-based resin, an acrylamide-based polymer, or an aminotriazine. System compounds and the like. Further, “two or more kinds of stabilizers” means that the above reactive nitrogen-containing compounds are two or more kinds, or one or more kinds of reactive nitrogen-containing compounds and one or more kinds of inorganic acid metal salts. Often means two or more different stabilizers as compounds.

<Reactive nitrogen-containing compound>
The stabilizer (B) preferably contains the reactive nitrogen-containing compound in an amount of 50 to 100% by mass of the stabilizer (B), more preferably 55 to 100% by mass, and further preferably 60 to 100% by mass. . By being in the above range, the mechanical component made of oxymethylene resin tends to be more excellent in productivity, conductivity, and durability.

  Although it does not specifically limit as a reactive nitrogen containing compound, For example, (1) Polyamide-type resin, (2) Acrylamide and its derivative (s), or the polymer containing them, (3) Hindered amine type compound, (4) Amino triazine type Compounds, (5) guanamine compounds, (6) urea compounds, and (7) hydrazide compounds. The above reactive nitrogen-containing compounds are used in a form supported on layered materials and porous materials (hydrotalcite, montmorillonite, silica gel, alumina, titania, zirconia, sepiolite, smectite, palygorskite, imogolite, zeolite, activated carbon, etc.) Is also possible.

(1) Polyamide-based resin The polyamide-based resin is not particularly limited. For example, nylon 4-6, nylon 6, nylon 6-6, nylon 6-10, nylon 6-12, nylon 12 and the like and copolymers thereof. Examples thereof include nylon 6 / 6-6, nylon 6 / 6-6 / 6-10, nylon 6 / 6-12, and the like.

(2) Acrylamide and its derivatives, or polymers containing them Acrylamide and its derivatives, or polymers containing them are not particularly limited, and examples include poly-β-alanine copolymers. These polymers and copolymers are disclosed in JP-B-6-12259 (corresponding to US Pat. No. 5,015,707), JP-B-5-87096, JP-B-5-47568 and JP-A-3-234729. It can manufacture by the method of each gazette description.

(3) Hindered amine compound The hindered amine compound is not particularly limited, and examples thereof include 4-acetoxy-2,2,6,6-tetramethylpiperidine, 4-stearoyloxy-2,2,6,6-tetramethyl. Piperidine, 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-tetramethylpiperidine, 4- (Phenylcarbamoyloxy) -2,2,6,6-tetramethylpiperidine, bis (2,2,6,6-tetramethyl-4-piperidine) -carbonate, bis (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. Of these, bis (2,2,6,6-tetramethyl-4-piperidyl) -sebacate is preferable.

(4) Aminotriazine-based compound The aminotriazine-based compound is not particularly limited. For example, melamine; melamine condensates such as melam, melem, and melon; melamine resins such as melamine formaldehyde resin; N, N ′, N ″ -N-hydroxyarylalkyl melamine compounds such as mono, bis, tris, tetrakis, pentakis, or hexakis (o-, m- or p-hydroxyphenylmethyl) melamine.

(5) Guanamin-based compound The guanamine-based compound is not particularly limited. For example, aliphatic guanamine-based compounds such as valerologamine, caproguanamine, heptanoguanamine, capuliguanamine, stearanamin; succinoguanamine, gluco Alkylenebisguanamines such as tagologamine, adipogguanamine, pimeloganamine, suboguanamine, azeroguanamine, sebacoguanamine; cyclohexanecarboguanamine, norbornenecarboguanamine, cyclohexenecarboguanamine, norbornanecarboguanamine, and functional group-substituted derivatives thereof Alicyclic guanamine compounds of the above; aromatic guanamine compounds such as benzoguanamine, α- or β-naphthoguanamine and their functional group-substituted derivatives; Polyguanamines such as isophthalologamine, terephthaloguanamine, naphthalenediguanamine, biphenylene diguanamine; aralkyl or aralkyleneguanamine such as phenylacetoguanamine, β-phenylpropioguanamine, o-, m- or p-xylylenebisguanamine Acetal group-containing guanamines, dioxane ring-containing guanamines, tetraoxospiro ring-containing guanamines, and isocyanuric ring-containing guanamines.

  The functional group-substituted derivative in the alicyclic guanamine-based compound is not particularly limited. For example, an alkyl group, a hydroxy group, an amino group, an acetamino group, a nitrile group, a carboxy group, an alkoxycarbonyl group, a carbamoyl group, an alkoxy group, Examples include derivatives in which 1 to 3 functional groups such as a phenyl group, a cumyl group, and a hydroxyphenyl group are substituted with a cycloalkane residue. In addition, the functional group-substituted derivative in the aromatic guanamine compound is not particularly limited, and examples thereof include an alkyl group, a hydroxy group, an amino group, an acetamino group, a nitrile group, a carboxy group, an alkoxycarbonyl group, a carbamoyl group, and an alkoxy group. , A derivative in which 1 to 5 functional groups such as phenyl group, cumyl group, and hydroxyphenyl group are substituted with a phenyl residue of benzoguanamine or a naphthyl residue of naphthoguanamine. Such compounds include, for example, o-, m- or p-toruguanamine, o-, m- or p-xyloganamine, o-, m- or p-phenylbenzoguanamine, o-, m- or p- Hydroxybenzoguanamine, 4- (4'-hydroxyphenyl) benzoguanamine, o-, m- or p-nitrile benzoguanamine, 3,5-dimethyl-4-hydroxybenzoguanamine, 3,5-di-t-butyl-4-hydroxybenzoguanamine Is exemplified.

  The acetal group-containing guanamines are not particularly limited, and examples thereof include 2,4-diamino-6- (3,3-dimethoxypropyl-s-triazine. The dioxane ring-containing guanamines include Although not particularly limited, for example, [2- (4′-6′-diamino-s-triazin-2′-yl) ethyl] -1,3-dioxane, [2- (4′-6′-diamino-s) -Triazin-2'-yl) ethyl] -4-ethyl-4-hydroxymethyl-1,3-dioxane Further, the tetraoxospiro ring-containing guanamines are not particularly limited, and examples thereof include CTU. -Guanamine, CMTU-guanamine, and the isocyanuric ring-containing guanamines are not particularly limited. 1,3,5-tris [2- (4 ′, 6′-diamino-s-triazin-2′-yl) ethyl] isocyanurate, 1,3,5-tris [3- (4 ′, 6′- And diamino-s-triazin-2′-yl) propyl] isocyanurate.

(6) Urea compound The urea compound is not particularly limited, and examples thereof include a chain urea compound and a cyclic urea compound. Although it does not specifically limit as a chain | strand-shaped urea type compound, For example, polyalkylene or arylene ureas, such as condensates of urea and formaldehyde, such as biurea, biuret, and form nitrogen, and polynonamethylene urea are mentioned. Specific examples of the cyclic urea-based compound are not particularly limited, and examples thereof include: hydantoins, clotylidene diurea, acetylene urea, mono, di, tri, or tetraalkoxymethyl glycol such as mono, di, tri, or tetramethoxymethyl glycoluril. Examples include uril, cyanuric acid, isocyanuric acid, uric acid, and urazole. Although it does not specifically limit as hydantoins, For example, hydantoin, 5-methylhydantoin, 5-ethylhydantoin, 5-isopropylhydantoin, 5-phenylhydantoin, 5-benzylhydantoin, 5,5-dimethylhydantoin, 5,5- Pentamethylenehydantoin, 5-methyl-5-phenylhydantoin, 5,5-diphenylhydantoin, 5- (o-, m- or p-hydroxyphenyl) hydantoin, 5- (o-, m- or p-aminophenyl) Metal salts such as Al salts of allantoin such as hydantoin, allantoin, 5-methyl allantoin, and allantoin dihydroxyaluminum salt may be mentioned.

(7) Hydrazide compound The hydrazide compound is not particularly limited, and examples thereof include an aliphatic carboxylic acid hydrazide compound, an alicyclic carboxylic acid hydrazide compound, and an aromatic carboxylic acid hydrazide compound. Specific examples of the aliphatic carboxylic acid hydrazide compounds include monocarboxylic acid hydrazides such as lauric acid hydrazide, stearic acid hydrazide, 12-hydroxystearic acid hydrazide, 1,2,3,4-butanetetracarboxylic acid hydrazide; Acid mono or dihydrazide, glutaric acid mono or dihydrazide, adipic acid mono or dihydrazide, pimelic acid mono or dihydrazide, suberic acid mono or dihydrazide, azelaic acid mono or dihydrazide, sebacic acid mono or dihydrazide, dodecanedioic acid mono or dihydrazide, hexadecanedi Examples thereof include polycarboxylic acid hydrazides such as acid mono- or dihydrazide, eicosane diacid mono- or dihydrazide, and 7,11-octadecadien-1,18-dicarbohydrazide. Specific examples of the alicyclic carboxylic acid hydrazide compounds include monocarboxylic acid hydrazides such as cyclohexanecarboxylic acid hydrazide; dimer acid mono or dihydrazide, trimer acid mono, di or trihydrazide, 1,2-, 1,3- Alternatively, polycarboxylic acid hydrazides such as 1,4-cyclohexanedicarboxylic acid mono- or dihydrazide, cyclohexanetricarboxylic acid mono-, di- or trihydrazide may be mentioned. Specific examples of the aromatic carboxylic acid hydrazide compound include monocarboxylic acid hydrazides such as benzoic acid hydrazide and functional group-substituted derivatives thereof, α- or β-naphthoic acid hydrazide and functional group-substituted derivatives thereof; Dihydrazide, terephthalic acid mono- or dihydrazide, 1,4- or 2,6-naphthalenedicarboxylic acid mono- or dihydrazide, 3,3'-, 3,4'- or 4,4'-diphenyldicarboxylic acid mono- or dihydrazide, diphenyl ether dicarboxylic acid Acid mono or dihydrazide, diphenylmethane dicarboxylic acid mono or dihydrazide, diphenylethane dicarboxylic acid mono or dihydrazide, diphenoxyethane dicarboxylic acid mono or dihydrazide, diphenyl sulfone dicarboxylic acid mono or dihydrazide, diphenyl ketone Dicarboxylic acid mono or dihydrazide, 4,4 ″ -terphenyl dicarboxylic acid mono or dihydrazide, 4,4 ′ ″-quarterphenyl dicarboxylic acid mono or dihydrazide, 1,2,4-benzenetricarboxylic acid mono, di or trihydrazide And polycarboxylic acid hydrazides such as pyromellitic acid mono, di, tri or tetrahydrazide, 1,4,5,8-naphthoic acid mono, di, tri or tetrahydrazide. Examples of benzoic hydrazide and functional group-substituted derivatives thereof include o-, m- or p-methylbenzoic hydrazide, 2,4-, 3,4-, 3,5- or 2,5-dimethylbenzoic hydrazide. O-, m- or p-hydroxybenzoic acid hydrazide, o-, m- or p-acetoxybenzoic acid hydrazide, 4-hydroxy-3-phenylbenzoic acid hydrazide, 4-acetoxy-3-phenylbenzoic acid hydrazide, 4 -Phenylbenzoic acid hydrazide, 4- (4'-phenyl) benzoic acid hydrazide, 4-hydroxy-3,5-dimethylbenzoic acid hydrazide, 4-hydroxy-3,5-di-t-butylbenzoic acid hydrazide, etc. Alkyl group, hydroxy group, acetoxy group, amino group, acetamino group, nitrile group, carboxy group, alkoxycarbonyl group, Derivatives in which 1 to 5 functional groups such as a carbamoyl group, an alkoxy group, a phenyl group, a benzyl group, a cumyl group, and a hydroxyphenyl group are substituted on the phenyl residue of benzoguanamine can be mentioned. Examples of α- or β-naphthoic acid hydrazide and functional group-substituted derivatives thereof include 3-hydroxy-2-naphthoic acid hydrazide and 6-hydroxy-2-naphthoic acid hydrazide.

<Metal salt of inorganic acid, metal oxide and metal salt of organic acid>
(1) Metal salt of inorganic acid The stabilizer (B) preferably contains 0 to 50% by mass of the metal salt of inorganic acid, more preferably 0 to 30% by mass of the stabilizer (B). More preferably, the content is 20% by mass.

  The metal salt of the inorganic acid is not particularly limited, and examples thereof include aluminum salts, iron salts, calcium salts, magnesium salts, sodium salts, potassium salts, strontium salts, barium salts such as silicic acid and carbonic acid. Specific examples include hydrated magnesium silicate, silica, calcium silicate, aluminum silicate, kaolin, wollastonite, calcium carbonate, magnesium carbonate and the like. Of these, hydrated magnesium silicate and calcium carbonate are preferable from the viewpoint of productivity of the oxymethylene resin-made mechanism part.

(2) Metal oxide The stabilizer (B) preferably contains 0 to 50% by mass of the metal oxide, more preferably 0 to 30% by mass, and more preferably 0 to 20% by mass of the stabilizer (B). More preferably.

  Although it does not specifically limit as a metal oxide, For example, titanium oxide, zinc oxide, magnesium oxide, barium oxide, aluminum oxide etc. are mentioned. Among these, zinc oxide and hydrotalcite are preferable from the viewpoint of productivity of mechanical parts made of oxymethylene resin.

(3) Metal salt of organic acid The stabilizer (B) preferably contains 0-50% by mass of the metal salt of organic acid, more preferably 0-30% by mass of the stabilizer (B). More preferably, the content is 20% by mass.

The metal salt of the organic acid is not particularly limited, for example, butyric acid, caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, Aluminum salts, iron salts, such as montanic acid, mellic acid, oleic acid, linoleic acid, ricinoleic acid, 12-hydroxystearic acid,
Calcium salts, magnesium salts, sodium salts, potassium salts, strontium salts, barium salts and the like can be mentioned. Specific examples include calcium stearate, magnesium stearate, calcium behenate, magnesium behenate, 12-hydroxycalcium stearate, and 12-hydroxymagnesium stearate. Of these, calcium stearate, magnesium stearate, and calcium 12-hydroxystearate are preferable from the viewpoint of productivity of the mechanical parts made of oxymethylene resin.

(Conductive carbon filler (C))
The oxymethylene resin composition used in the present embodiment contains 5.0 to 15.0 parts by mass of a conductive carbon filler (C) with respect to 100 parts by mass of polyoxymethylene, and 5.5 to 13.5 parts by mass. Part is preferably included, and more preferably 6.0 to 12.0 parts by mass. By being in the above range, the mechanical component made of oxymethylene resin tends to be more excellent in productivity, conductivity, and durability.

  Although it does not specifically limit as a conductive carbon type filler (C), Specifically, carbon black, graphite, carbon fiber, etc. are mentioned. The shape of the conductive carbon filler (C) is not particularly limited, and may be powder, scale, plate, needle, sphere, fiber, tetrapod, or the like. Among these, it is preferable that the conductive carbon-based filler (C) includes a particulate conductive carbon-based filler that is less affected by orientation. Here, the term “particulate” means that the major axis and minor axis of the particles are about the same, and this ratio (major axis / minor axis) is preferably 8 or less, more preferably 6 or less, and further preferably 4 or less. Thereby, the mechanical component made of oxymethylene resin tends to be more excellent in productivity, conductivity, and durability. In addition, the major axis and minor axis of the conductive carbon filler (C) in this specification can be measured as follows. The conductive carbon-based filler to be inspected is sampled, and the sampled particle image is taken with a scanning electron microscope (SEM) at a magnification of 1,000 to 1,000,000, and at least 100 randomly selected in the obtained image The maximum particle diameter and the minimum particle diameter of each conductive carbon-based filler are measured, and the arithmetic average values of the obtained particle diameters are obtained as the average major axis and minor axis. Further, the average particle diameter shown below is the average major axis. The content of the particulate conductive carbon filler in the conductive carbon filler (C) is preferably 30 to 100% by mass, more preferably 40 to 100% by mass, and 50 to 100. More preferably, it is mass%.

<Carbon black>
Examples of the carbon black include conductive carbon black. Among the conductive carbon blacks, those having a small average particle diameter or a large surface area and a developed chain structure are preferable. Specifically, the average particle size is preferably 0.05 μm or less, more preferably 0.04 μm or less, and even more preferably 0.03 μm or less. The surface area of the DBP oil absorption (ASTM D2415-65T) is preferably 300 ml / 100 g or more, more preferably 350 ml / 100 g or more, and further preferably 400 ml / 100 g or more. If the particle diameter and DBP oil absorption are in the above ranges, good conductivity can be obtained even if the amount of carbon black added is small.

  Specific carbon blacks include, for example, ketjen black EC [DBP oil absorption: 350 ml / 100 g, particulate], EC-300J [DBP oil absorption: 365 ml / 100 g, particulate], EC-600JD [DBP oil absorption : 480 ml / 100 g, particulate form] (manufactured by Lion Akzo Corporation), Printex XE2-B [DBP oil absorption: 420 ml / 100 g, particulate form] (manufactured by Degussa Corporation), and the like. Carbon black may be used alone or in combination of two or more.

<Graphite>
The graphite is not particularly limited and can be appropriately selected from artificial products and natural products according to the purpose. The shape of the graphite powder is not particularly limited, and may be any of powder, scale, plate, needle, sphere, fiber, tetrapod, etc. Natural graphite is preferred. The average particle diameter of graphite is preferably in the range of 0.5 to 100 μm, more preferably 1 to 80 μm, and still more preferably 2 to 70 μm. When the thickness is 0.5 μm or more, more excellent conductivity tends to be exhibited, and when the thickness is 100 μm or less, the handling property and the molded product surface appearance retention tend to be superior. The average particle diameter can be measured by the same method as described above.

  Specific graphites include, for example, F # 3 [average particle diameter 60 μm, scaly], CPB [average particle diameter 19 μm, scaly], J-CPB [average particle diameter 5 μm, scaly] (manufactured by Nippon Graphite) , CNP15 [average particle diameter 15 μm, scaly], Z-5F [average particle diameter 5 μm, scaly] (manufactured by Ito Graphite Industries) and the like. In addition, graphite may be used individually by 1 type, or may use 2 or more types together.

<Carbon fiber>
The carbon fiber is not particularly limited, and any of fibers (PAN-based fiber or PITCH-based fiber) made by carbonizing acrylic fiber or pitch (by-products such as petroleum, coal, coal tar, etc.) at a high temperature as a raw material. Can also be selected. The carbon fiber used in the oxymethylene resin mechanism part used in the present embodiment has a fine diameter of preferably 1 to 25 μm, more preferably 2 to 20 μm, and even more preferably 3 to 18 μm. . The fiber length is preferably such that it is not oriented. In this specification, the fine diameter is obtained by sampling the carbon fiber in the same manner as described above, and photographing the sampled fiber image with a scanning electron microscope (SEM) at a magnification of 1,000 to 1,000,000 times. The diameters of at least 100 carbon fibers selected at random are measured, and the arithmetic average value of the obtained diameters is obtained as the average diameter. The ratio of the major axis to the minor axis in the carbon fiber is the ratio of the fiber length to the fiber diameter.

  Specific carbon fibers include, for example, trading card (manufactured by Toray Industries, Inc.), tenax (manufactured by Teijin Ltd.), pyrophil (manufactured by Mitsubishi Rayon Co., Ltd.), DIALEAD (manufactured by Mitsubishi Plastics), Creca (Manufactured by Kureha Co., Ltd.), Z-5F (manufactured by Ito Graphite Industries Co., Ltd.) and the like, all of which are fibrous with a fine diameter of 3-18 μm. In addition, carbon fiber may be used individually by 1 type, or may use 2 or more types together.

  In addition, in order to improve affinity with resin in an oxymethylene resin composition, what was processed with the well-known surface treating agent may be used for a conductive carbon type filler (C). Such a surface treatment agent is not particularly limited. For example, silane coupling agents such as aminosilane and epoxysilane, titanate coupling agents, fatty acids such as saturated fatty acids or unsaturated fatty acids, alicyclic carboxylic acids, resins Examples include acids, metal soaps, and resins. The addition amount of the surface treatment agent is preferably 3% by mass or less, and more preferably 2% by mass or less with respect to the conductive carbon filler (C).

(Thermosetting resin (D))
The oxymethylene resin composition used in the present embodiment includes 0.5 to 5.0 parts by mass, and 1.0 to 3.5 parts by mass of the thermosetting resin (D) with respect to 100 parts by mass of polyoxymethylene. It is preferable to include 1.5 to 3.0 parts by mass. By being in the above range, the mechanical component made of oxymethylene resin tends to be more excellent in productivity, conductivity, and durability.

  The thermosetting resin (D) is not particularly limited, and examples thereof include an epoxy resin, a phenol resin, a melamine resin, a urethane resin, a urea resin, and an allyl resin. Among these, the thermosetting resin (D) preferably contains an epoxy resin or a phenol resin, and more preferably contains an epoxy resin having a glycidyl group capable of reacting with either acid or alkali. In addition, a thermosetting resin (D) may be used individually by 1 type, or may use 2 or more types together.

<Epoxy resin>
The epoxy resin is a compound obtained by oxidizing a mono- or polyfunctional glycidyl derivative or a compound having an unsaturated bond to generate an epoxy group. Such an epoxy resin is not particularly limited. For example, 2-ethylhexyl glycidyl ether, 2-methyloctyl glycidyl ether, lauryl glycidyl ether, stearyl glycidyl ether, behenyl glycidyl ether, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether Glycidyl ether (unit of ethylene oxide; 2 to 30), propylene glycol diglycidyl ether (unit of propylene oxide; 2 to 30), neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, Glycerin triglycidyl ether, trimethylolpropane diglycidyl ether, trimethylolpropane triglycidyl Ether, bisphenol A diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, sorbitan monoester diglycidyl ether, sorbitan monoester triglycidyl ether, pentaerythritol triglycidyl ether, pentaerythritol tetraglycidyl ether, diglycerin triglycidyl ether, diglycerin Examples include tetraglycidyl ether, condensate of cresol novolak and epichlorohydrin (epoxy equivalent: 100 to 400, softening point: 20 to 150 ° C.), glycidyl methacrylate, coconut fatty acid glycidyl ester, soybean fatty acid glycidyl ester, and the like. Among these, a cresol novolak type epoxy resin that is a condensate of cresol novolak and epichlorohydrin is preferable, and an ortho cresol type epoxy resin that is a polyglycidyl etherified product of a polycondensate of orthocresol and formaldehyde is more preferable.

<Phenolic resin>
The phenolic resin is not limited as long as it is obtained by reacting phenol with formaldehyde, but a novolak type phenolic resin reacted with an acidic catalyst is preferable. The molecular weight is preferably one having a weight average molecular weight of 500 to 10,000. A phenolic resin further modified with paraxylylene or alkylbenzene is preferable, and an alkylbenzene-modified phenolic resin having a modification rate of 40% or more is more preferable. Furthermore, the unreacted phenol contained in the phenolic resin is preferably 5% by mass or less, and more preferably 2% by mass or less.

(Curing agent (E))
The oxymethylene resin composition used in the present embodiment contains 0.3 to 3.0 parts by mass of two or more curing agents (E) with respect to 100 parts by mass of polyoxymethylene, and 0.6 to 2.0 masses. Part, preferably 0.8 to 1.5 parts by mass. By being in the above range, the mechanical component made of oxymethylene resin tends to be more excellent in productivity, conductivity, and durability.

  Although it does not specifically limit as a hardening | curing agent (a hardening accelerator is included), For example, Basic phosphorus compounds; Basic nitrogen compounds, such as an aliphatic amine, a polyamidoamine, and an aromatic amine; Acid and an acid anhydride type compound; Substituted imidazole compounds; tertiary amine compounds; morpholine compounds; dicyandiamide derivatives and the like. The curing agent (E) preferably contains a basic phosphorus compound, and more preferably contains 80% by mass or more of the basic phosphorus compound. Further, the “two or more kinds of curing agents” may be two or more kinds of the basic phosphorus compounds or the like, or may be one or more kinds of basic phosphorus compounds and one or more kinds of basic nitrogen compounds. Means two or more different curing agents as compounds.

  Specifically, the curing agent (E) particularly preferably contains 80 to 100% by mass of a basic phosphorus compound, more preferably 85 to 100% by mass, and further preferably 95 to 100% by mass. . By being in the above range, the mechanical component made of oxymethylene resin tends to be more excellent in productivity, conductivity, and durability.

Although it does not specifically limit as said basic phosphorus type compound, For example, the triphenylphosphine, methyl substituted triphenylphosphine, methoxy substituted triphenylphosphine, etc. which are shown by following formula (I) are mentioned.
(In the formula (I), R, R ′ and R ″ are each a hydrogen atom, a methyl group or a methoxy group.)

  Although it does not specifically limit as a compound shown by Formula (I), Specifically, a triphenylphosphine, a tri-m-tolylphosphine, a tri-p-tolylphosphine, a di-m-tolylphenylphosphine, a di-p -Tolylphenylphosphine, m-tolyldiphenylphosphine, p-tolyldiphenylphosphine, tri-p-methoxyphenylphosphine, di (p-methoxyphenyl) phenylphosphine, (p-methoxyphenyl) diphenylphosphine and the like.

  The basic nitrogen compound is not particularly limited, and examples thereof include diethylenetriamine (DTA), triethylenetetramine (TTA), diethylaminopropylamine (DEPA), N-aminoethylpiperazine (N-AEP), and benzyldimethylamine (BDMA). ), Metaphenylenediamine (MPD), diaminodiphenylmethane (DDM), diaminodiphenylsulfone (DDS), dicyandiamide, boron trifluoride monoethylamine (BF3 · MEA), menthanediamine, xylylenediamine, bisaminopropyl Examples include tetraoxaspiroundecane adduct (BATUA), imidazole, 2-ethyl-4-methylimidazole (EMI), and the like.

  The acid anhydride compound is not particularly limited. For example, phthalic anhydride (PA), maleic anhydride (MA), dodecyl succinic anhydride (DDSA), hexahydrophthalic anhydride (HHPA), methyl nadic anhydride (MNA), pyromellitic anhydride (PMDA), benzophenone tetracarboxylic anhydride (BTDA) and the like.

Further, the curing accelerator is not particularly limited. For example, a substituted imidazole compound represented by the following formula (II), a tertiary amine compound represented by the formula (III), a morpholine compound represented by the formula (IV), And dicyandiamide derivatives represented by the formula (V).
(In the formula (II), R1 is a substituted or unsubstituted alkyl group, aryl group, allyl group or vinyl group, and R2, R3 and R4 are each a hydrogen atom, a substituted or unsubstituted alkyl group or an aryl group. Group, allyl group or vinyl group, which may be the same or different from each other.)
(In Formula (III), R5 is a substituted or unsubstituted alkyl group or aryl group having 8 or more carbon atoms, R6 and R7 are each a substituted or unsubstituted alkyl group or aryl group, and they are the same. May be different from each other.)
(In Formula (IV), R8 is a substituted or unsubstituted alkyl group or aryl group having 8 or more carbon atoms.)
(In the formula (V), R9, R10, R11, and R12 are _{each, (- C 2 H 4 O} ) x - (- C 3 H 6 O) y -H ( wherein, x and y are x + y = 1-20, x = 0-20, and y = 0-20, the random copolymer or block copolymer residues), which may be the same. And they may be different from each other.)

  In the above compound, when R1 to R7 are alkyl groups, those having 1 to 30 carbon atoms are preferred. Moreover, when R5 and R8 are alkyl groups, those having 8 to 30 carbon atoms are preferred.

  The substituted imidazole compound represented by the above formula (II) is not particularly limited. For example, 1-hydroxyethyl-2-methylimidazole, 1-cyanoethyl-2-heptadecylimidazole, 1-vinyl-2-phenylimidazole 1-lauryl-2-undecylimidazole, 1-allyl-2-isopropylimidazole, 1-benzyl-2-ethylimidazole, 1-stearyl-2-methyl-4-ethylimidazole, 1-ethyl-5-laurylimidazole 1-phenyl-4-ethylimidazole, 1-tolyl-2-heptadecylimidazole, 1-triphenylmethylimidazole, 1- (behenylbenzyl) -2-methylimidazole, 2- (behenylbenzyl) imidazole, 4- ( Behenylbenzyl) imidazo Le, 5- (behenyl benzyl) imidazole, and the like.

  The tertiary amine compound represented by the formula (III) is not particularly limited. For example, octyldimethylamine, octyldiethylamine, dioctylmethylamine, trioctylamine, stearyldimethylamine, stearyldiethylamine, distearylmethylamine, Distearylpropylamine, tristearylamine, behenylstearylmethylamine, behenyldimethylamine, behenyldiethylamine, dibehenylmethylamine, dibehenylisopropylamine, tribehenylamine, trilaurylamine, octyldihydroxyethylamine, benzyldimethylamine, benzyldibutylamine, Benzylstearylmethylamine, p-octylphenyldimethylamine, trisdimethylaminobenzene, trisdi Chill aminophenol, tris dimethylamino toluene, tris (dimethylaminomethyl) phenol, triflate El amines, tritolylamine, diphenyl tolyl amine, (behenyl benzyl) dimethylamine, di (behenyl benzyl) methylamine, and the like.

  The morpholine compound represented by the formula (IV) is not particularly limited, and examples thereof include cutyl morpholine, lauryl morpholine, cetyl morpholine, stearyl morpholine, behenyl morpholine, phenyl morpholine, p-lauryl phenyl morpholine, tolyl morpholine, Examples thereof include benzylmorpholine, p-methylbenzylmorpholine, behenylbenzylmorpholine and the like.

  Although it does not specifically limit as a dicyandiamide derivative represented by the said formula (V), For example, what added ethylene oxide, propylene oxide, or both to dicyandiamide is mentioned. Examples of such dicyandiamide derivatives include, but are not limited to, for example, 4 mol ethylene oxide adduct of dicyandiamide, 4 mol propylene oxide adduct to dicyandiamide, 10 mol ethylene oxide adduct to dicyandiamide, 10 mol propylene to dicyandiamide. Oxide adduct, 4 mol ethylene oxide / 7 mol propylene oxide copolymer adduct to dicyandiamide, 10 mol ethylene oxide / 7 mol propylene oxide copolymer adduct to dicyandiamide, 10 mol ethylene oxide / 30 mol propylene to dicyandiamide Oxide copolymer adduct (however, one mole or more of ethylene oxide or propylene oxide added to all four active hydrogens of dicyandiamide) One ethylene oxide added to the active hydrogen, that the total number of moles of added propylene oxide does not exceed 20 mol), and the like.

(Other additives (F))
The oxymethylene resin composition used in the present embodiment may contain other conventionally known additives (F) as necessary. The content of the other additive (F) contained in the oxymethylene resin composition is preferably 0 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the polyoxymethylene (A). The amount is more preferably 8 parts by mass or less, and further preferably 0 part by mass or more and 5 parts by mass or less.

  Other additives (F) are not particularly limited. For example, antioxidants other than those mentioned above, heat stabilizers, weathering (light) agents, lubricants, various inorganic / organic fillers, crystal nucleating agents, release agents And other thermoplastic resins / thermoplastic elastomers, appearance improvers such as pigments / dyes, and the like. In particular, it is preferable that the other additive (F) further includes a sliding agent. In particular, as with the stabilizer (B) and the curing agent (E), the additive (F) contains as little acid as possible and / or contains an acid. A sliding agent that does not easily occur is preferred. Specific examples include olefin-based sliding agents, silicon-based sliding agents, fluorine-based sliding agents, alkylene oxide-based sliding agents, and high molecular weight alcohols. Thus, durability may be improved by including a sliding agent.

(Method for producing oxymethylene resin composition)
Below, the manufacturing method of the oxymethylene resin composition containing (A) component-(E) component is demonstrated exemplarily. Said polyoxymethylene (A), two or more types of stabilizers (B), conductive carbon filler (C), thermosetting resin (D), two or more types of curing agents (E), and as required Accordingly, the other additive (F) is mixed. This mixing can be performed by adding the components (B) to (F) and granulating the polyoxymethylene (A) during granulation.

  In addition, after granulation of polyoxymethylene (A), after newly mixing components (A) to (F) using a Henschel mixer, tumbler, or V-shaped blender, kneader, roll mill, single screw extrusion An oxymethylene resin composition can also be obtained by melt-kneading these using a machine, a twin-screw extruder, or a multi-screw extruder. In addition, the components (A) to (F) may be divided and added several times during melt-kneading.

  Moreover, in order to improve the dispersibility of (B) component-(F) component with respect to polyoxymethylene (A), the part or whole quantity of the pellet of polyoxymethylene (A) to mix is grind | pulverized, and (B) component It may be melt-mixed after being previously mixed with the component (F). In this case, the dispersibility may be further increased by using a spreading agent. The spreading agent is not particularly limited, and examples thereof include aliphatic hydrocarbons and aromatic hydrocarbons, modified products thereof and mixtures thereof, and fatty acid esters of polyols.

  It is preferable that the temperature of the said melt mixing is 180-230 degreeC. Further, from the viewpoint of maintaining the quality and working environment, it is preferable to perform deaeration by replacement with an inert gas or single-stage and multistage vents.

  Furthermore, the oxymethylene resin composition used in the present embodiment may be obtained from a molded product. For example, the molded product may be pulverized and the obtained flakes may be used in place of the pellets. Moreover, you may mix a part of grind | pulverized flake with the pellet obtained from the above.

  The following method is mentioned as a manufacturing method of a preferable oxymethylene resin composition. As the apparatus, a twin-screw extruder equipped with a decompression device and a plurality of side feeders is preferable. The polyoxymethylene resin composition of the present embodiment can be obtained by melting and kneading the above components using such an apparatus. In the melt-kneading method, all components except the component (C) are supplied from the top, melt-kneaded, and the component (C) is supplied from the side feeder located downstream from the top. Furthermore, it is not necessary to add other components from at least one of the side feeders provided downstream from the top. Furthermore, it is preferable to supply (C) component from two side feeders. At this time, the decompression degree of the extruder is preferably 0 to 0.07 MPa.

[3. Manufacturing method of mechanical parts made of oxymethylene resin]
The mechanical component made of oxymethylene resin used in the present embodiment can be obtained, for example, by molding the oxymethylene resin composition described above. As a manufacturing method of the mechanical component made of oxymethylene resin used in the present embodiment, various known molding methods using a conventional oxymethylene resin composition as a raw material can be employed. In addition, a molded product until the initial molding conditions are stabilized, or a runner portion that is molded at the same time as the product at the time of molding may not be used as a product, and this may be mixed with resin pellets and molded.

  The molding method is not particularly limited. For example, extrusion molding, injection molding, vacuum molding, blow molding, injection compression molding, decorative molding, multicolor molding, gas assist injection molding, firing injection molding, low pressure molding, super molding, etc. Examples of molding methods include thin-wall injection molding (ultra-high-speed injection molding) and in-mold composite molding (insert molding, outsert molding). In particular, from the viewpoint of productivity, extrusion molding / injection molding / injection compression molding, or multicolor molding / in-mold composite molding in which different materials are combined is preferable. As the molding conditions, recommended conditions under which polyoxymethylene is usually molded are used. For example, it is preferable to perform molding at a resin temperature of 180 to 230 ° C. and a mold temperature of 60 to 120 ° C. Further, the surface state of the oxymethylene resin mechanism part used in the present embodiment may be smooth or subjected to various embossing processes.

[4. Recycled physical properties of molded products]
The oxymethylene resin composition is a component constituting the oxymethylene resin mechanical component used in the present embodiment, and the strength of the molded body obtained by pulverizing and molding the molded body of the oxymethylene resin composition is 45 MPa or more. Yes, the elongation is 10% or more. The physical properties shown here are values measured at an environmental temperature of 23 ± 2 ° C. and a humidity of 50 ± 10%.

<Molded product obtained by pulverizing and molding a molded product of the oxymethylene resin composition>
By molding the oxymethylene resin composition, the oxymethylene resin composition is heated and melted, and pressure is applied to form a mechanical component. Hereinafter, a molded product obtained by pulverizing and molding a molded product of the oxymethylene resin composition is also referred to as a recycled material.

<Strength of recycled materials>
The strength of the 100% by mass recycled material used in the present embodiment is 45 MPa or more, preferably 46 MPa or more, and more preferably 47 MPa or more. The test piece for evaluation used for the measurement of strength is a type I injection molded piece based on ASTM D638. This test piece for evaluation is confirmed to be free of short shots or burrs using, for example, a molding machine (Toshiba Machine; IS-100E, cylinder temperature 200 ° C., mold temperature 80 ° C., cooling time 30 seconds). While molding. Further, after molding, the substrate is left and adjusted for 16 hours or more at an environmental temperature of 23 ± 2 ° C. and a humidity of 50 ± 10%. As with the above, the strength of the recycled material is determined according to ASTM D638 by, for example, using a universal testing machine (Shimadzu Corporation; Autograph AGS-X, equipped with an extensometer), etc., at a test speed of 5 mm / min. Test and evaluate. Strength has a uniform and stable morphology, and tends to increase when thermal stability is maintained, resulting in agglomeration and poor dispersion of the conductive carbon filler, poor thermal stability, and The density tends to decrease as the density decreases.

<Elongation of recycled materials>
The elongation of the 100 mass% recycled material used in the present embodiment is 10% or more, more preferably 12% or more, and further preferably 14% or more. The test piece for evaluation used for measuring the elongation is a type I injection-molded piece conforming to ASTM D638 as described above. The elongation of the recycled material is in accordance with ASTM D638 in the same manner as described above, for example, with a universal testing machine (Shimadzu Corporation; Autograph AGS-X, equipped with extensometer), etc., at a test speed of 5 mm / min. Perform a tensile test and evaluate. Elongation, like strength, has a uniform and stable morphology and tends to increase when thermal stability is maintained, causing conductive carbon fillers to agglomerate and poorly disperse, and thermal stability. However, when the density of the recycled material is low, it tends to be small.

  When the physical property values of the strength and elongation of the recycled material are in the above numerical range, the mechanical component made of oxymethylene resin is excellent in productivity, conductivity, and durability.

  Further, the physical properties of the recycled material being in the above numerical range indicate that the recycled material tends to be excellent in thermal stability. Therefore, the additive (F) as described above can be further added, and functions such as weather resistance, slidability, and good appearance can be imparted.

  Furthermore, by confirming the specific composition of the present invention and the physical properties of the recycled material, the stability of the mechanical behavior of the original polyoxymethylene resin composition, the detachability of additives, the change in morphology, etc. Can be determined. For example, due to the physical properties of recycled materials, it can be seen that the mechanical parts have a decrease in electrical conductivity that cannot be noticed during the manufacture of mechanical components, and the odors that occur during the pulverization of molded products and the molding of recycled materials I understand the decline.

  From the above, in addition to the features of the polyoxymethylene resin composition, the physical properties of the molded body (also referred to as “100% by mass recycled material” in the present specification) formed by pulverizing the molded body of the oxymethylene resin composition are as described above. By satisfying this value, it is possible to maintain the productivity of the mechanical parts made of oxymethylene resin and improve the durability.

[5. Use of mechanical parts made of oxymethylene resin]
The use environment and applications of the oxymethylene resin mechanism parts of this embodiment will be described below.

<Usage environment>
The mechanical component made of oxymethylene resin according to the present embodiment is mainly preferably used indoors, and can be used outdoors, that is, under an environment such as ultraviolet rays or rain. In addition, when using mechanical parts made of oxymethylene resin as a joining part, it is preferable to maintain the joining state safely, and it is excellent in durability when displacement at a high speed or an instantaneous impact load is applied. Is preferred. Moreover, it is preferable that the said joining component is excellent also in durability, when repeated joining and removal are performed.

  The mechanism component made of oxymethylene resin according to the present embodiment uses a mechanism that utilizes a reaction force generated by deforming a part or the whole of the component, such as matching the shape of unevenness or the like, or having a snap fit structure. Therefore, when used, creep may occur constantly or intermittently. As described above, the joining component is composed of a male part and / or a female part. Either of these may be the joining component of the present embodiment, or both.

<Application>
The oxymethylene resin mechanism component of the present embodiment is not particularly limited. For example, the boss, rib, clip, button, holder, connector, joint, snap fit, wheel, roller, roller, washer, spacer, bush, rotor, It is preferably a component having at least one mechanism selected from the group consisting of a bat, a swivel, a bearing, a shaft hole, a shaft, a pulley, and a gear.

  Although it does not specifically limit as a use of the oxymethylene resin mechanism parts of this embodiment, For example, OA equipment, music, video, information communication equipment, electrical and electronic equipment, automobile, industrial equipment, agricultural equipment, medical equipment, clothing And use for joint parts such as sundry goods. More specifically, exterior decorative plates, various electrical piping, clips used for fixing gaseous or liquid fuel piping to the body of automobiles and industrial facilities (piping clips), telecommunications equipment And sensor holders (sensor holders), connectors for connecting and connecting metal tubes and cables (cable connectors), and the like.

  Hereinafter, the present invention will be described in more detail with reference to specific examples and comparative examples. However, the present invention is not limited to the following examples.

First, the oxymethylene resin composition (P) and the like that form the oxymethylene resin-made mechanism parts in Examples and Comparative Examples will be described.
[Oxymethylene resin composition (P) forming mechanical parts made of oxymethylene resin]
As raw materials for preparing the oxymethylene resin composition (P), the following polyoxymethylene (A) and stabilizer (B) were used.

(raw materials)
<Polyoxymethylene (A)>
(1) Production of polyoxymethylene Polyoxymethylene was prepared as follows. First, the polymerization process was performed as follows. Self-cleaning type biaxial paddle type continuous mixing reactor with a jacket through which a heat medium can pass (screw diameter 3 inches, ratio of length L to diameter D (hereinafter referred to as “L / D”) = 10). Adjusted to 80 ° C. Trioxane was adjusted as 3,750 g / hr as a main monomer, 1,3-dioxolane as 25-150 g / hr as a comonomer, and methylal as a chain transfer agent was adjusted in a range of 2.0-8.0 g / hr, A continuous mixing reactor was continuously fed.

Further, a 1% by mass cyclohexane solution of boron trifluoride di-n-butyl etherate as a polymerization catalyst was adjusted so that the catalyst was 2.0 × 10 ⁻⁵ mol with respect to 1 mol of trioxane, and the continuous mixing was performed. Polymerization was carried out by adding to the reactor to obtain polymerized flakes.

  After pulverizing the obtained polymerization flakes, the pulverized product was put into a 1% by mass aqueous solution of triethylamine and stirred to deactivate the polymerization catalyst. Thereafter, a 1% by mass aqueous solution of triethylamine containing polymerized flakes was sequentially filtered, washed and dried to obtain a crude polyoxymethylene copolymer.

When 1 mass part of the obtained crude polyoxymethylene copolymer is converted to the amount of nitrogen by using the following formula (α), triethyl (2-hydroxyethyl) ammonium formate as a quaternary ammonium compound is 20 ppm. Was added and mixed uniformly, followed by drying at 120 ° C. for 3 hours to obtain a dry polymer.
Addition amount of quaternary ammonium compound = P × 14 / Q (α)
(In the formula (α), P represents the concentration (mass ppm) of the quaternary ammonium compound relative to the crude polyoxymethylene copolymer, “14” represents the atomic weight of nitrogen, and Q represents the molecular weight of the quaternary ammonium compound. .)

  Next, the terminal stabilization and granulation process were implemented as follows using the obtained dry polymer. Add the obtained dry polymer to the front part of a screw type twin screw extruder with a vent (Plastic Industry Co., Ltd., BT-30, L / D = 44, set temperature 200 ° C., rotation speed 80 rpm), and 0.5 parts by mass of water was added to 100 parts by mass of the dry polymer, and vacuum degassing was performed while stabilizing the polymer ends.

  Next, 0.2 parts by mass of Irganox 245 (manufactured by Ciba Specialty Chemicals Co., Ltd.) as a stabilizer was mixed in advance with a Henschel mixer for 1 minute with respect to 100 parts by mass of the dry polymer. The obtained mixture was added from the side feeder in the latter part of the above twin screw extruder and a screw type twin screw extruder with a vent set to 200 ° C. (BT-30, L / D = Plastic Industries Co., Ltd.). 44), the number of revolutions of the screw was 80 rpm, and the mixture was melt-kneaded at 24 amperes to obtain polyoxymethylene (A-1) pellets. From raw material input to pellet collection, the operation was performed while avoiding oxygen contamination as much as possible. Furthermore, the said comonomer and chain transfer agent were adjusted, and 3 types of polyoxymethylene (A-2)-(A-4) was obtained by the same operation.

(2) Evaluation of polyoxymethylene The melt flow rates (MFR) of the four types of polyoxymethylenes (A-1) to (A-4) obtained were measured. The results are shown in Table 1 below. Here, the melt flow rate was determined as follows. The pellets of the above polyoxymethylene (A-1) to (A-4) were used, and dried in an oven (GPH-102, manufactured by Espec Corp.) at 80 ° C. for 2 hours before measurement. Then, it measured based on ASTM D1238 (temperature 190 degreeC) using the melt indexer (Toyo Seiki Co., Ltd. product, F-W01).

  Moreover, the ratio (henceforth "b / a") of the oxyalkylene unit b (mol) with respect to the oxymethylene unit a (100 mol) of four types of polyoxymethylene (A-1)-(A-4) obtained. ) The results are shown in Table 1 below. Here, (b / a) was obtained as follows. By dissolving the polyoxymethylene pellets in a solvent hexafluoroisopropanol (HFIP) -d2 (D conversion rate 97%, Wako Pure Chemicals 98% assay) over 24 hours, the polyoxymethylene 1 A 5% by weight solution was prepared. Using a 1.5% by mass solution of the above polyoxymethylene as a specimen, using a JEOL-400 nuclear magnetic resonance spectrometer (1H: 400 MHz), under conditions of 55 ° C. and 500 accumulations, the oxymethylene unit a and the The assigned peaks with the oxyalkylene unit b excluding the unit a were integrated. From the integrated value thus obtained, the ratio of the oxyalkylene unit b (mol) to the oxymethylene unit a (100 mol) was determined.

<Stabilizer (B)>
The following (B-1) to (B-7) were used as the stabilizer (B).
(B-1): Reactive nitrogen-containing compound (Asahi Kasei Chemicals Corporation, polyamide compound / NA100)
(B-2): Reactive nitrogen-containing compound (manufactured by Nissan Chemical Industries, Ltd., melamine compound / 2,4,6-triamino-1,3,5 triazine)
(B-3): Reactive nitrogen-containing compound (Asahi Kasei Finechem Co., Ltd., poly β-alanine compound / H3)
(B-4): Reactive nitrogen-containing compound (Sankyo Lifetech Co., Ltd., hindered amine compound / Sanol LS-770)
(B-5): Reactive nitrogen-containing compound (Nippon Finechem Co., Ltd., hydrazide compound / SDH)
(B-6): Metal salt of organic acid (manufactured by Nitto Kasei Co., Ltd., calcium distearate / HCS)
(B-7): Metal salt of inorganic acid (manufactured by Nippon Talc Co., Ltd., hydrated metal silicate / MS talc)

<Conductive carbon filler (C)>
The following (C-1) to (C-34) were used as the conductive carbon filler (C).
(C-1): Carbon black (manufactured by Lion Akzo Co., Ltd., Ketjen EC, particulate form; (major axis / minor axis) ≦ 4)
(C-2): Carbon fiber (manufactured by Mitsubishi Rayon Co., Ltd., short fiber CF / TR06Q, fibrous; (major axis / minor axis)> 8)
(C-3): Carbon black (Eponic Degussa Japan Co., Ltd., Printex XE2, particulate form; (major axis / minor axis) ≦ 4)
(C-4): Carbon fiber (manufactured by Toray Industries, Inc., milled CF 30 μm / MLD 30, fibrous; 8 ≧ (major axis / minor axis)> 4)

<Thermosetting resin (D)>
The following (D-1) to (D-3) were used as the thermosetting resin (D).
(D-1): Epoxy resin (Asahi Kasei Chemicals Corporation ECN280)
(D-2): Epoxy resin (Asahi Kasei Chemicals Corporation ECN1299)
(D-3): Phenolic resin (manufactured by Sumitomo Durez Co., Ltd., PR50731)

<Curing agent (E)>
The following (E-1) to (E-3) were used as the curing agent (E).
(E-1): Basic phosphorus compound (Kitahiro Chemical Co., Ltd., TPP)
(E-2): Basic phosphorus compound (manufactured by Wako Chemical Co., Ltd., diphenyl (p-tolyl) phosphine)
(E-3): Dicyandiamide derivative (Nippon Carbide Corporation, dicyandiamide)

<Other additives (F)>
The following (F-1) to (F-4) were used as other additives (F).
(F-1): Olefin-based flexible material (manufactured by Mitsui Chemicals, Tuffmer A4085 / ethylene-butene copolymer)
(F-2): Alcohol-based sliding agent (manufactured by NOF Corporation, NAA-422 / behenyl alcohol)
(F-3): Silicone sliding agent (Shin-Etsu Chemical Co., Ltd., X22-2159 / polydimethylsiloxane-containing MB)
(F-4): Fatty acid ester-based sliding agent (manufactured by Nippon Oil & Fats Co., Ltd., Spam acetyl / cetyl myristate)

(Preparation of oxymethylene resin composition (P))
Using the raw materials (A) to (F), oxymethylene resin compositions (P0 to P44) were produced with the blending amounts shown in Tables 2 and 3 below. Specifically, a twin-screw extruder (TEM-48SS extruder manufactured by Toshiba Machine Co., Ltd. (L / D = 58.4, consisting of 1 to 14 independent barrel zones, top feed from 1 to 7 and 10) More side feed is possible, it has a vacuum vent port at 13. It also has a die head at the tip portion 15))) is melt kneaded and pelletized to produce pellets of the oxymethylene resin composition (P). did. The feed of the raw material was performed from the top by a mixture in which all components except the component (C) were uniformly mixed with a blender, and the component (C) was performed from the side from the barrel zone 7 alone. At this time, the side feeder in the barrel zone 10 was set to a state in which nothing was supplied (empty), and deaeration was performed from the barrel zone 13 by a vacuum pump. An oxymethylene resin composition (P) was obtained by melt-kneading under the conditions of a screw speed of 300 rpm and an extrusion rate of 200 kg / h, solidifying with a strand bath and pelletizing.

[Examples 1 to 20, Reference Examples 21 and 22, Examples 23 to 31, Comparative Examples 1 to 14, Reference Example 1]
[Production of mechanical parts made of oxymethylene resin]
Using the oxymethylene resin composition (P0 to P44), Examples 1 to 20, Reference Examples 21 and 22, Examples 23 to 31 and Comparative Examples having a fitting mechanism in the mechanism as shown in FIG. 1 to 14 and mechanical parts made of oxymethylene resin of Reference Example 1 were prepared as follows.

(Production of mechanical parts)
Using the prepared oxymethylene resin compositions (P0) to (P44), using an injection molding machine (manufactured by Nippon Seiko Co., Ltd., J110AD-180H), the cylinder temperature is 200 ° C. and the mold temperature is 80 ° C. Then, the mechanical parts as shown in FIG. 4 were produced by injection molding while sufficiently filling and confirming that no burrs were produced. In FIG. 5, the photograph of the evaluation site | part of the oxymethylene resin-made mechanism components used for evaluation in the Example is shown.

[Measurement of physical properties of recycled materials]
After producing a mechanical component as described above using the pellets (P0) to (P44) of the oxymethylene resin composition, the mechanical component was pulverized (manufactured by Hadano Sangyo Co., Ltd., pulverizer DD-2-3. The flakes were pulverized according to 7) to a maximum of 3 mm. Using these flakes, physical properties (strength and elongation) were measured by the following methods. All measurements were performed at an environmental temperature of 23 ± 2 ° C. and a humidity of 50 ± 10%, and were performed at n = 5, and the average was used as a physical property value. The results are shown in Tables 4 and 5 above.

(Strength)
The test piece for evaluation used for the strength measurement was a type I injection molded piece in accordance with ASTM D638. Molding was performed using an injection molding machine (Toshiba Machine; IS-100E, cylinder temperature 200 ° C., mold temperature 80 ° C., cooling time 30 seconds) while confirming that no short shots or burrs were generated. Further, after molding, the substrate was left and adjusted for 16 hours or more at an environmental temperature of 23 ± 2 ° C. and a humidity of 50 ± 10%. In addition, the strength was evaluated in accordance with ASTM D638 as described above, for example, by performing a tensile test with a universal testing machine (Shimadzu Corporation; Autograph AGS-X, equipped with an extensometer) at a test speed of 5 mm / min. It was set as the strength of the resin composition.

(Elongation)
The test piece for evaluation used for measuring the elongation was a type I injection-molded piece based on ASTM D638 as described above. In addition, the elongation is evaluated in accordance with ASTM D638 in the same manner as described above, for example, by performing a tensile test with a universal testing machine (Shimadzu Corporation; Autograph AGS-X, equipped with extensometer) at a test speed of 5 mm / min. It was set as the elongation of the methylene resin composition.

[Evaluation of mechanical parts made of oxymethylene resin]
Regarding the mechanical parts made of oxymethylene resin, the productivity, conductivity and durability were evaluated as follows. The evaluation results are shown in Table 4 and Table 5 below.

(Evaluation of productivity of mechanical parts made of oxymethylene resin)
The evaluation of the productivity of the oxymethylene resin mechanism part was performed by the following evaluation of the productivity of the oxymethylene resin composition and the moldability of the oxymethylene resin mechanism part.

<Productivity evaluation of oxymethylene resin composition>
The productivity evaluation of the oxymethylene resin composition is based on the average granulation amount per unit time at the same electric power based on the granulation of the oxymethylene resin composition P0 in which only polyoxymethylene and carbon black are melt-kneaded. The strand state, the appearance of the pellet and the odor were comprehensively performed. The evaluation criteria are shown below.
[Evaluation criteria]
×: When it is clearly reduced compared with the productivity of P0 ◇: When it is at the same level as compared with the productivity of P0 ○: Improved compared with the productivity of P0 Case ◎: When significant improvement is seen compared to P0 productivity

Note that the above “obviously reduced” means that when the average granulation rate reduction rate per unit time is larger than 40% when compared with P0, the bite is broken and the strands are broken and wound. Is unstable, or the appearance (color or shape) of the pellet is bad, or the odor of the pellet is strong, which affects workability.
The above “improvement” means that when the increase in the average granulation amount per unit time is 5% or more and less than 10% when compared with P0, the average granulation amount does not change significantly. When the appearance (color and shape) of the pellet is improved, or when the odor of the pellet is reduced and workability is improved.
Furthermore, the above “significant improvement” means that the increase in the average granulation amount per unit time is 10% or more and the appearance (color and shape) of the pellets is good when compared with P0. Or when the operability is improved by reducing the odor of the pellets.

<Formability evaluation of mechanical parts made of oxymethylene resin>
The moldability evaluation of the mechanical part produced using the oxymethylene resin composition is based on the case where the mechanical part is molded using the oxymethylene resin composition P0 obtained by melt-kneading polyoxymethylene and carbon black. Then, the appearance (silver, flow mark, etc.), the colored state (bleeding, whitening), the mold deposit, etc. of the molded product after 1,000 shot molding were visually confirmed and performed comprehensively. The evaluation took the average of five of the molded mechanical parts. The evaluation criteria are shown below.
[Evaluation criteria]
×: When it is clearly reduced as compared with the moldability of P0 ◇: When it is at the same level as the moldability of P0 ○: Compared with the moldability of P0, an improvement was observed Case ◎: When significant improvement is seen compared to the moldability of P0

In addition, the above “obviously decreased” refers to a case where deterioration of mold deposits or obvious defects such as silver or flow mark are confirmed in the entire mechanical component.
The above-mentioned “improvement” means a case where improvement is observed in one or more points such as improvement of mold deposit, silver, flow mark, bleed and the like.
Furthermore, the “significant improvement” refers to the case where the mold transfer is greatly improved and the smoothness and glossiness are improved.

(Evaluation of conductivity of mechanical parts made of oxymethylene resin)
Four-probe ASP probe (four pins with 5mm between pins and 0.37mm pin tip, spring pressure 210g / 1, compatible with JIS K7194) at the AA 'portion of the oxymethylene resin mechanism part shown in FIG. The volume resistivity was measured at a measurement voltage of 90 V using a Loresta-GP manufactured by Mitsubishi Chemical Corporation and evaluated. The evaluation criteria for volume resistivity are shown below.
[Evaluation criteria]
×: When volume resistivity is 500 Ω · cm or more Δ: When volume resistivity is 100 Ω · cm or more and less than 500 Ω · cm ◇: When volume resistivity is 50 Ω · cm or more and less than 100 Ω · cm ○: Volume resistivity is When 10 Ω · cm or more and less than 50 Ω · cm ◎: When the volume resistivity is less than 10 Ω · cm

(Evaluation of durability of mechanical parts made of oxymethylene resin)
Evaluation of the durability of mechanical parts made of oxymethylene resin is based on repeated installation of the same pipes, the mounting force required when fitting pipes (Yazaki Kako Co., Ltd., 28Φ Elector Pipe HGA-4000) to oxymethylene mechanical parts. Evaluation was performed based on detachability when fitting, and fitting retention when a similar pipe was fitted and a load was applied under high temperature. All the evaluations were performed three times, and the average was used as the evaluation value.

<Evaluation of wearing power>
As shown in FIG. 6, the force when fixing the mechanical parts made of oxymethylene resin and fitting the pipe (50 mm / min) was measured using a universal testing machine (Shimadzu Corporation; Autograph AGS-X), The load at this time was used as an evaluation value of the mounting force. The mounting force was evaluated according to the following evaluation criteria.
[Evaluation criteria]
×: When the load is less than 100N △: When the load is 100N or more and less than 120N ◇: When the load is 120N or more and less than 130N ○: When the load is 130N or more and less than 140N ◎: When the load is 140N or more

<Evaluation of detachability>
As shown above, the mechanical parts made of oxymethylene resin are fixed as shown in FIG. 6, and the pipe is lowered and fitted at 100 mm / sec for 1 second and raised at 100 mm / sec for 0.5 second after fitting. “Removal, wait for 0.5 seconds” was repeated, and the number of times until destruction or loss of function was determined as an evaluation value of detachability. The detachability was evaluated according to the following evaluation criteria.
[Evaluation criteria]
×: When the number of times is less than 500 times △: When the number of times is 500 times or more and less than 800 times ◇: When the number of times is 800 times or more and less than 1,000 times ○: The number of times is 1,000 times or more and less than 1,500 times ◎ : When the number of times is 1,500 times or more

<Evaluation of fitting retention>
As shown in FIG. 7, the mechanical part made of oxymethylene resin is fixed, the pipe is fitted, the mechanical part is loaded so as to overlap with the pipe to 10 kg, and left in an oven at 80 ° C. in that state. The time until destruction or loss of function was taken as the evaluation value. The fitting retention was evaluated according to the following evaluation criteria.
[Evaluation criteria]
×: When the time is less than 400 hours Δ: When the time is 400 hours or more and less than 600 hours ◇: When the time is 600 hours or more and less than 800 hours ○: When the time is 800 hours or more and less than 1,000 hours ◎: Time Is over 1,000 hours

[Examples 1 to 3, Comparative Examples 1 to 4, Reference Example 1]
The evaluation results of the mechanical parts of Examples 1 to 3, Comparative Examples 1 to 4, and Reference Example 1 are shown in Table 4 below. From the evaluation results of Examples 1 to 3, Comparative Examples 1 to 4, and Reference Example 1, the oxymethylene resin composition contains two or more kinds of stabilizers in a predetermined range as defined in the present invention, and other raw materials. In addition, it was found that the mechanical parts made of oxymethylene resin are excellent in productivity, conductivity, and durability by satisfying the physical property regulations of the recycled material. Further, in Reference Example 1, as compared with the mechanical part molding, the mechanical part was pulverized and the test piece was molded, and the odor was significantly increased. On the other hand, each example had less odor than the reference example 1 even when the mechanical parts were pulverized and the test piece was molded.

[Examples 4 and 5, Comparative Examples 5 and 6]
The evaluation results of the mechanical components of Examples 4 and 5 and Comparative Examples 5 and 6 are shown in Table 4 below. From the evaluation results of Examples 2, 4, 5, Comparative Examples 5, 6, and Reference Example 1, the oxymethylene resin composition contains a conductive carbon-based filler within a predetermined range as defined in the present invention, It was found that the mechanical parts made of oxymethylene resin are excellent in productivity, conductivity, and durability by satisfying the physical property regulations of other raw materials and recycled materials.

[Examples 6 and 7, Comparative Examples 7 and 8]
The evaluation results of the mechanical parts of Examples 6 and 7 and Comparative Examples 7 and 8 are shown in Table 4 below. From the evaluation results of Examples 2, 6, 7, Comparative Examples 7, 8, and Reference Example 1, the oxymethylene resin composition contains a thermosetting resin in a predetermined range as defined in the present invention, and other raw materials. In addition, it was found that the mechanical parts made of oxymethylene resin are excellent in productivity, conductivity, and durability by satisfying the physical property regulations of the recycled material.

[Examples 8 and 9, Comparative Examples 9 to 12]
The evaluation results of the mechanical components of Examples 8 and 9 and Comparative Examples 9 to 12 are shown in Table 4 below. From the evaluation results of Examples 2, 8, 9 and Comparative Examples 9-12 and Reference Example 1, the oxymethylene resin composition contains two or more kinds of curing agents in a predetermined range as defined in the present invention, It was found that the mechanical parts made of oxymethylene resin are excellent in productivity, conductivity, and durability by satisfying the physical property regulations of other raw materials and recycled materials.

[Comparative Examples 13 and 14]
The evaluation results of the mechanical parts of Comparative Examples 13 and 14 are shown in Table 4 below. From the evaluation results of Example 2, Comparative Examples 13 to 14 and Reference Example 1, as specified in the present invention, the recycled material of the oxymethylene resin composition is within a predetermined physical property range, and other raw materials are within a predetermined range. It was found that the mechanical parts made of oxymethylene resin are excellent in productivity, conductivity, and durability. Moreover, the strength of the recycled material of Comparative Example 14 was greatly reduced as compared with the initial strength of the used composition P23.

[Examples 10 to 12]
The evaluation results of the mechanical parts of Examples 10 to 12 are shown in Table 5 below. From the evaluation results of Examples 2, 10 to 12, and Reference Example 1, the oxymethylene resin composition contains the preferred polyoxymethylene of the present invention and satisfies the provisions of physical properties of other raw materials and recycled materials. It has been found that the resin mechanical parts are excellent in productivity, conductivity, and durability.

[Examples 13 to 20]
The evaluation results of the mechanical parts of Examples 13 to 20 are shown in Table 5 below. From the evaluation results of Examples 2, 13 to 20, and Reference Example 1, the oxymethylene resin composition contained a predetermined amount of the preferred stabilizer of the present invention, and satisfied the provisions of physical properties of other raw materials and recycled materials. It was found that the mechanical component made of methylene resin is excellent in productivity, conductivity, and durability.

[ Reference Examples 21 and 22]
The evaluation results of the mechanical parts of Reference Examples 21 and 22 are shown in Table 5 below. From the evaluation results of Example 2, Reference Examples 21 and 22, and Reference Example 1, the oxymethylene resin composition contains a predetermined amount of the preferred conductive carbon-based stabilizer of the present invention, and defines the physical properties of other raw materials and recycled materials. When satisfied, the oxymethylene resin mechanical parts were found to be excellent in productivity, conductivity, and durability.

[Examples 23 and 24]
The evaluation results of the mechanical parts of Examples 23 and 24 are shown in Table 5 below. From the evaluation results of Examples 2, 23, and 24 and Reference Example 1, the oxymethylene resin composition contains a preferable thermosetting resin of the present invention, and satisfies the provisions of physical properties of other raw materials and recycled materials. It was found that the mechanical component made of methylene resin is excellent in productivity, conductivity, and durability.

[Examples 25 to 27]
The evaluation results of the mechanical parts of Examples 25 to 27 are shown in Table 5 below. From the evaluation results of Examples 2, 25 to 27, and Reference Example 1, the oxymethylene resin composition contains the preferable curing agent of the present invention, and satisfies the provisions of physical properties of other raw materials and recycled materials. The mechanical parts were found to be excellent in productivity, conductivity, and durability.

[Examples 28 to 30]
The evaluation results of the mechanical components of Examples 28 to 30 are shown in Table 5 below. From the evaluation results of Examples 2, 28 to 30 and Reference Example 1, the oxymethylene resin composition contains a preferable additive of the present invention, and satisfies the provisions of physical properties of other raw materials and recycled materials. The mechanical parts were found to be excellent in productivity, conductivity, and durability.

[Example 31]
Using the same composition as P3, it was divided from the top and barrel zone 7 at the ratio of (7: 3) that all components except component (C) were fed from the top during manufacturing. Evaluation was performed in the same manner as in Example 2 except that feeding was performed. The evaluation results are shown in Table 5 below. From the evaluation results of Examples 2 and 31, it was found that the oxymethylene resin composition was excellent in productivity, conductivity, and durability by using the above-described production method.

  The mechanical parts made of oxymethylene resin according to the present invention are excellent in productivity, conductivity, and durability, and therefore all or part of mechanical parts such as joints and fittings of electrical equipment, automobile parts and other various parts. As an industrial applicability.

Claims (6)

100 parts by mass of polyoxymethylene (A),
0.02 to 1.00 parts by mass of two or more kinds of stabilizers (B),
Conductive carbon black (C) 5.0-15.0 parts by mass;
0.5 to 5.0 parts by mass of thermosetting resin (D),
And two or more curing agent (E) 0.3 to 3.0 parts by weight, only contains, and
The stabilizer (B) includes an oxymethylene resin composition, which is a reactive nitrogen-containing compound, a metal salt of an inorganic acid, a metal oxide, or a metal salt of an organic acid ,
The molded product obtained by pulverizing and molding the molded product of the oxymethylene resin composition has a tensile yield strength of 45 MPa or more and a tensile breaking elongation of 10% or more.
Mechanical parts made of oxymethylene resin. The mechanical component made of oxymethylene resin according to claim 1, wherein the polyoxymethylene (A) contains a comonomer unit other than the oxymethylene unit in an amount of 0.3 mol or more with respect to 100 mol of the oxymethylene unit. The mechanical component made of oxymethylene resin according to claim 1 or 2, wherein the stabilizer (B) contains 50 mass% or more of a reactive nitrogen-containing compound. The thermosetting resin (D) comprises Epoxy resins, polyoxymethylene resin mechanical part according to any one of claims 1-3. Wherein the curing agent (E) is a basic re down of compounds containing more than 80 wt%, oxymethylene resin mechanical part according to any one of claims 1-4. The mechanical component made of oxymethylene resin according to any one of claims 1 to 5 , further comprising a sliding agent.