JP2013116971A - Slide member made of polyoxymethylene - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a slide member made of polyoxymethylene, which has excellent workability and durability while securing practically sufficient productivity.SOLUTION: In a slide member made of polyoxymethylene, a member (I) formed using an oxymethylene resin composition is brought into contact with a counterpart member (II), wherein the oxymethylene resin composition comprises: 100 pts.mass of the polyoxymethylene (A); and ≥1 pt.mass and <25 pts.mass of a lubricant (B) that shows a solid state at normal temperature. The member (I) has a Rockwell hardness (M scale) of 78 to 98. The counterpart member (II) is formed by using a resin other than the oxymethylene resin and has a Rockwell hardness (M scale) of 55 to 120.

Description

  The present invention relates to a polyoxymethylene slide part.

  Oxymethylene resin is a resin with high mechanical strength and rigidity, excellent oil resistance and organic solvent resistance, balanced in a wide temperature range, and easy to process. It is used for a wide range of applications, centering on mechanical parts of equipment, automobile parts and other mechanical parts. Oxymethylene resins are originally used for various slide parts because of their excellent self-lubricating properties.

  In slide parts, the shape of various sliding parts such as surfaces and surfaces, surfaces and lines, surfaces and points, the contact state of the sliding surface where the sliding surface is always constant or updated, The friction resistance and wear resistance of the member varies depending on the movement of parts such as continuous motion or reciprocating motion, and the usage environment such as temperature and humidity during sliding. In particular, since a tendency has not been simply derived for the friction resistance and wear resistance between resins, many proposals have been made so far.

  About an oxymethylene resin composition, in order to improve friction resistance and abrasion resistance, various structures are mentioned. For example, a composite resin composition composed of polyacetal resin, zinc oxide whisker, and fluororesin is excellent in friction resistance and wear resistance in continuous contact / continuous movement between the surface on which the composition is molded and the surface composed of iron material ( For example, refer to Patent Document 1), or a synthetic resin sliding member containing polyacetal resin (POM), silicon carbide, and tetrafluoroethylene polymer resin (PTFE) is a discontinuous material composed of pins and stainless steel made of the composition. It has been reported that excellent contact resistance and discontinuous movement have excellent friction resistance and wear resistance (see, for example, Patent Document 2).

  Various reports have been made on the combination of a member for sliding and a mating member of the member. For example, in a guide slider for a window lifting mechanism, a combination of a spherical material made of polybutylene terephthalate (PBT) resin and a guide made of polyacetal resin improves the occurrence of looseness in discontinuous contact and discontinuous movement. (For example, see Patent Document 3), and in a wear-resistant connector for a modular link type conveyor belt, a combination of a rod coated with polyester or polyamide and an acetal link allows continuous contact and non-contact. There have been reports of excellent friction resistance and wear resistance in continuous movement (see, for example, Patent Document 4).

  Moreover, various forms are mentioned about utilization to the slide components of oxymethylene resin.

  For example, in order to reduce changes in the coefficient of friction when a slider-formed plate is subjected to discontinuous contact and discontinuous movements after performing immersion and weather resistance tests on a slider, polyacetal resin, fluorine Proposals have been made such as using a composition comprising a resin and carbon black for the sliding membrane (see, for example, Patent Document 5). Also, in the sliding member and door check device using it, as a shoe to obtain wear resistance and smooth slidability when discontinuous contact / discontinuous movement between the shoe and arm There are proposals such as using a composition comprising a polyacetal resin, a thermoplastic polyester elastomer, and a lubricant, and using polyamide as an arm (see, for example, Patent Document 6).

JP-A-5-255571 JP-A-8-239682 JP-A-10-227176 Special table 2009-506962 gazette Japanese Patent Laid-Open No. 2002-188585 Japanese Patent Laid-Open No. 2005-187591

  In recent years, from the viewpoint of weight reduction and economy, there has been an active movement to change the material used from metal to resin, and the slide mechanism of resin and resin is also increasing in slide parts. For these resin slide parts, smooth operation and long-term durability are required as in the conventional case.

  However, the various members using the oxymethylene resin disclosed in Patent Documents 1 to 6 still have room for improvement in terms of operability and durability when sliding with a resin material having a specific hardness.

  Therefore, the present invention provides a polyoxymethylene slide part capable of realizing high operability and excellent durability when sliding with a resin material having a specific hardness while ensuring practically sufficient productivity. For the purpose.

  As a result of intensive studies in order to solve the above problems, the present inventors, as a member contacting when sliding with a resin material having a specific hardness, a member formed using a specific oxymethylene resin composition As a result, it has been found that a slide part having high operability and excellent durability can be obtained, and the present invention has been completed.

That is, the present invention is as follows.
[1]
The member (I) formed using the oxymethylene resin composition is a slide component that contacts the counterpart material (II),
The oxymethylene resin composition contains 100 parts by mass of polyoxymethylene (A) and 1 part by mass or more and less than 25 parts by mass of a solid lubricant (B) at room temperature,
The member (I) has a Rockwell hardness (M scale) of 78 to 98,
The polyoxymethylene slide part, wherein the counterpart material (II) is formed using a resin other than oxymethylene resin and has a Rockwell hardness (M scale) of 55 to 120.
[2]
The polyoxymethylene slide part of [1], wherein the oxymethylene resin composition has a melt flow rate (MFR) of 2 to 20 g / 10 minutes.
[3]
[1] or [2], wherein the polyoxymethylene (A) contains a comonomer unit other than an oxymethylene unit in an amount of 0 to 1.35 mol with respect to 100 mol of the oxymethylene unit. Polyoxymethylene slide parts.
[4]
The sliding part made of polyoxymethylene according to any one of [1] to [3], wherein the lubricant (B) has a melting point of 60 ° C or higher.
[5]
The sliding part made of polyoxymethylene according to any one of [1] to [4], wherein the lubricant (B) has a melting point of 200 ° C or higher.
[6]
The oxymethylene resin composition contains 100 parts by mass of polyoxymethylene (A) and 5 parts by mass or more and less than 10 parts by mass of a solid lubricant (B) at room temperature [1] to [5] ] The slide part made from polyoxymethylene in any one of.
[7]
The polyoxymethylene slide part according to any one of [1] to [6], wherein the counterpart material (II) uses a reinforced resin.
[8]
Use of the polyoxymethylene slide part according to any one of [1] to [7], wherein the polyoxymethylene slide part is used.
[9]
A method of using a slide component comprising a member (I) formed using an oxymethylene resin composition and a counterpart material (II) in contact with the member (I),
The method for using a polyoxymethylene slide part according to [8], wherein a steady sliding surface pressure between the member (I) and the counterpart material (II) is 20 to 150 MPa.
[10]
A method of using a slide component comprising a member (I) formed using an oxymethylene resin composition and a counterpart material (II) in contact with the member (I),
The steady sliding linear velocity between the member (I) and the counterpart material (II) is 0.08 to 2.3 m / sec, which is made of polyoxymethylene according to [8] or [9] How to use slide parts.
[11]
[1] A method of using a polyoxymethylene slide part according to any one of [1] to [7], wherein the polyoxymethylene slide part is constantly and intermittently operated.

  According to the present invention, it is possible to obtain a polyoxymethylene slide part which is improved in terms of operability and durability when sliding with a resin material having a specific hardness while ensuring practically sufficient productivity.

It is the figure which showed an example (example 1) of the slide component which concerns on this embodiment. It is the figure which showed the case where the slide component of an example (example 1) of the slide component which concerns on this embodiment slides. It is the figure which showed an example (example 2) of the slide component which concerns on this embodiment. It is the figure which showed an example (example 2) of the slide component which concerns on this embodiment from right side. It is the figure which showed an example (example 3) of the slide components which concern on this embodiment. It is the figure which showed the case where the slide part of an example (Example 3) which concerns on this embodiment slides, without rolling. It is the schematic of the apparatus which evaluates the slide components obtained in the present Example. It is a figure of the guide part front of the apparatus which evaluates the slide components obtained in the present Example. It is a figure of the slide pin front surface of the apparatus which evaluates the slide components obtained in the present Example.

  Hereinafter, modes for carrying out the present invention (hereinafter referred to as “the present embodiment”) will be described. The present invention is not limited to the following description, and various modifications can be made within the scope of the gist thereof.

  The usage aspect of the polyoxymethylene slide part and the polyoxymethylene slide part of this embodiment will be described in detail sequentially.

[Polyoxymethylene slide parts]
The slide part made of polyoxymethylene of this embodiment is a slide part in which the member (I) formed using the oxymethylene resin composition is in contact with the counterpart material (II), and the oxymethylene resin composition is 100 parts by weight of polyoxymethylene (A) and 1 part by weight or more and less than 25 parts by weight of a solid lubricant (B) at room temperature, and the member (I) has a Rockwell hardness (M scale) of 78 to 98 The counterpart material (II) is formed using a resin other than oxymethylene resin and has a Rockwell hardness (M scale) of 55 to 120.

[Member (I)]
The polyoxymethylene slide part of the present embodiment includes a member (I) formed using a specific oxymethylene resin composition described later.

[Oxymethylene resin composition]
The oxymethylene resin composition used in the present embodiment contains the following polyoxymethylene (A) as a main component, and further contains a specific amount of a lubricant (B) that is solid at room temperature.

(Polyoxymethylene (A))
The polyoxymethylene (A) used in this embodiment is a polyoxymethylene homopolymer (A-1) having only an oxymethylene group in the main chain, or an oxyalkylene unit having 2 or more carbon atoms in the molecule. It is a polyoxymethylene copolymer (A-2).

  The polyoxymethylene (A) preferably contains 0 to 1.35 mol, more preferably 0 to 1.33 mol of comonomer units other than oxymethylene units with respect to 100 mol of oxymethylene units. More preferably, it is more preferably 0 to 1.31 mol. When the content of the comonomer unit other than the oxymethylene unit is within the above range, the slide part including the member (I) formed using the oxymethylene resin composition can maintain high productivity and has excellent operability. And tends to be durable.

The quantification of the comonomer unit can be determined by the following procedure using ¹ H-NMR method. The obtained polyoxymethylene (A) was dissolved with 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 ).

  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 an oxymethylene group in the main chain. Both ends of the polymer chain 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 JP-B-47-6420 and JP-B-47-10059). be able to. Thereby, the crude polyoxymethylene whose terminal is not stabilized can be obtained.

1) Monomer As the monomer used for the production of the 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. A known method (for example, a method described in JP-B-5-32374 and JP-A-2001-521916) can be used as a purification method of formaldehyde.

  The formaldehyde gas used in the present embodiment is preferably one that contains as little impurities as possible, such as water, methanol, and formic acid, which have a polymerization termination and chain transfer action during the polymerization reaction. If these impurities are not contained as much as possible, an unexpected chain transfer reaction can be avoided and a polyoxymethylene homopolymer (A-1) having a target molecular weight can be easily obtained. In particular, water is preferably 100 ppm or less, and more preferably 50 ppm or less.

2) Chain transfer agent As chain transfer agent used for manufacture of polyoxymethylene homopolymer (A-1), alcohols and acid anhydrides can be generally used. In order to obtain a block polymer or a branched polymer, a polyol, a polyether polyol, or a polyether polyol / alkylene oxide may be used.

  Moreover, it is preferable to use a chain transfer agent that does not contain impurities as much as possible. Among these, water is preferably 2000 ppm or less, more preferably 1000 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 a method of removing impurities and purifying them. The chain transfer agent used here may be used alone or in combination of two or more.

3) Polymerization catalyst Examples of the polymerization catalyst used for the polymerization reaction in the production of the polyoxymethylene homopolymer (A-1) include onium salt polymerization catalysts. As the onium salt-based polymerization catalyst used in the polymerization reaction, those represented by the following general formula (1) can be used.

[R ₁ R ₂ R ₃ R ₄ M] ⁺ X ⁻ (1)
In the general formula (1), R ₁ , R ₂ , R ₃ and R ₄ each independently represents an alkyl group, M represents an element having a lone pair, and X represents a nucleophilic group.

  Among the onium salt polymerization catalysts represented by the general formula (1), quaternary ammonium salt compounds and quaternary phosphonium salt compounds are preferably used. More preferably, tetramethylammonium bromide, dimethyl distearyl ammonium acetate, tetraethylphosphonium iodide, or tributylethylphosphonium iodide is used.

4) Reactor As a polymerization reactor in the production of the polyoxymethylene homopolymer (A-1), there are a batch type reaction vessel with a stirrer, a continuous type kneader, a twin screw type continuous extrusion kneader, and a twin screw paddle. A 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 blocking the terminal stabilization of the crude polyoxymethylene with an ether group, there is a method described in JP-B 63-452, and a method for blocking with an acetyl group is the United States. A method of using a large amount of acid anhydride described in Japanese Patent No. 3,459,709 in a slurry state and an acid anhydride gas described in US Pat. No. 3,172,736 There is a method in the gas phase. In the present embodiment, any of the above methods can be adopted and is not particularly limited.

  The etherifying agent used for blocking with an ether group includes orthoesters, usually orthoesters of aliphatic or aromatic acids with aliphatic, alicyclic or aromatic alcohols. Specific examples of such orthoesters include 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 by converting 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 in the etherification reaction include low-boiling aliphatics such as pentane, hexane, cyclohexane and benzene, alicyclic and aromatic hydrocarbons, halogenated lower aliphatic compounds such as methylene chloride, chloroform and carbon tetrachloride, etc. These organic solvents are mentioned.

  On the other hand, when the terminal of the polymer is blocked with an ester group, examples of the organic acid anhydride used for esterification include organic acid anhydrides represented by the following general formula (2).

R ₅ COOCOR ₆ (2)
In the general formula (2), R ₅ and R ₆ each independently represents an alkyl group. R ₅ and R ₆ may be the same or different.

  Among the organic acid anhydrides represented by the general formula (2), propionic anhydride, benzoic anhydride, acetic anhydride, succinic anhydride, maleic anhydride, glutaric anhydride, phthalic anhydride and the like are preferable, and acetic anhydride is preferable. Particularly preferred. One organic acid anhydride may be used, but two or more organic acid anhydrides may be used.

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

It is preferable that the terminal hydroxyl group concentration is reduced to 5 × 10 ⁻⁷ mol / g or less by blocking the end of polyoxymethylene with an ether group and / or an ester group. The concentration of the terminal hydroxyl group is preferably 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.

(3) Granulation step After the terminal stabilized polyoxymethylene powder is dried, it may be granulated using an extruder in order 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. When performing melt-kneading, it is preferable to carry out replacement with an inert gas and deaeration with a single-stage or multistage vent in order to maintain 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)>
(1) Polymerization process The polymerization form in the production of the polyoxymethylene copolymer (A-2) used in the present embodiment contains 1.35 mol or less of comonomer units other than oxymethylene units with respect to 100 mol of oxymethylene units. The content is preferably 1.33 mol or less, and more preferably 1.31 mol or less.

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

  Materials such as main monomers used in the polymerization step will be described below.

1) Main monomer As the main monomer used in the production of the polyoxymethylene copolymer (A-2), it is preferable to use cyclic oligomers such as formaldehyde or its trimer trioxane or tetramer tetraoxane.

  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 As the comonomer used for producing the polyoxymethylene copolymer (A-2), it is preferable to use a cyclic ether compound having an oxyalkylene unit having 2 or more carbon atoms in the molecule.

  Examples of such cyclic ether compounds include ethylene oxide, propylene oxide, 1,3-dioxolane, 1,3-propanediol formal, 1,4-butanediol formal, 1,5-pentanediol formal, and 1,6-hexanediol. One compound selected from the group consisting of formal, diethylene glycol formal, 1,3,5-trioxepane, 1,3,6-trioxycan, and a mono- or di-glycidyl compound capable of constituting a branched or crosslinked structure in the molecule or Mixtures of two or more are listed as suitable.

  When polymerizing the polyoxymethylene copolymer (A-2), as the main monomer and comonomer, those containing as little impurities as possible, such as water, methanol and formic acid, which have a polymerization stopping action and a chain transfer action during the polymerization reaction are used. It is preferable.

  By using a main monomer and a comonomer containing as little impurities as possible, an unexpected chain transfer reaction can be avoided, and a polymer having a desired molecular weight can be 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 a desired low-impurity main monomer and comonomer, a known method (for example, the main monomer is described in JP-A-3-123777 and JP-A-7-33761, the 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).

  As the chain transfer agent, for example, formaldehyde dialkyl acetals and oligomers thereof, and lower aliphatic alcohols such as methanol, ethanol, propanol, isopropanol and butanol are preferably used. 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 a polyether polyol and an alkylene oxide adduct of the polyether polyol. 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, those having a small number of unstable terminals are preferred.

4) Polymerization catalyst The polymerization catalyst used in the polymerization step of the polyoxymethylene copolymer (A-2) is preferably a cationically active catalyst such as Lewis acid, protonic acid, and ester or anhydride of protonic acid.

  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, but perchloric acid, trifluoromethanesulfonic acid, perchloric acid-tertiary butyl ester, acetyl perchlorate, and trimethyloxonium hexafluorophosphate are included. Can be mentioned. If necessary, for example, a catalyst for reducing the formation of terminal formate groups described in JP-A No. 05-05017 may be used in combination. Among these, boron trifluoride; boron trifluoride hydrate; a coordination complex compound of an organic compound containing oxygen atom or sulfur atom and boron trifluoride is 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 amount of the polymerization catalyst is preferably 1 × 10 ⁻⁶ to 1 × 10 ⁻³ mol with respect to 1 mol of the total amount of monomers, 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 organic solvent solution containing a catalyst neutralization deactivator and stirring in a slurry state for generally several minutes to several hours. it can.

  The catalyst neutralization deactivator is not particularly limited, but examples thereof include amines such as ammonia, triethylamine and tri-n-butylamine, and alkali metal and alkaline earth metal hydroxides, inorganic acid salts, and organic acids. 1 or more types selected from the group which consists of salt are mentioned.

  In addition, the catalyst is deactivated by contacting a vapor such as ammonia and triethylamine with polyoxymethylene to deactivate the polymerization catalyst, or by contacting with at least one of hindered amines, triphenylphosphine and calcium hydroxide in a mixer. A deactivation method can also be used.

(2) Terminal stabilization step and granulation step An oxymethylene resin composition 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. To obtain a polyoxymethylene copolymer (A-2).

  The method for decomposing and removing the unstable terminal portion contained in the crude polymer is not particularly limited. For example, a known basic substance can be obtained using a vented single-screw extruder or a vented twin-screw extruder. In the presence of a decomposition / removal agent to be described later, there is a method in which the crude polymer is melted to decompose and remove the unstable terminal portion.

  When performing melt-kneading for terminal stabilization, it is preferable to perform replacement with an inert gas and deaeration with single-stage and multistage vents in order to maintain quality and working environment.

  The temperature at the time of melt-kneading is preferably not lower than the melting point of the polyoxymethylene copolymer (A-2) and not higher than 260 ° C.

  Furthermore, it is preferable to perform granulation by melt mixing while adding a known stabilizer that can be added to ordinary polyoxymethylene.

1) Decomposition removing agent Examples of the decomposing / removing agent used for decomposing and removing the unstable terminal portion contained in the crude polymer of the polyoxymethylene copolymer (A-2) include aliphatic amines such as ammonia, triethylamine and tributylamine, and Well-known basic substances such as alkali metal or alkaline earth metal hydroxides such as calcium hydroxide, inorganic weak acid salts and organic weak acid salts may be mentioned.

  Among the decomposition and removal agents, at least one quaternary ammonium compound represented by the following general formula (3) is preferable.

  A method of treating a thermally unstable terminal using such a quaternary ammonium compound can be suitably used.

[R ₇ R ₈ R ₉ R ₁₀ N ⁺ ] _n Y ⁿ⁻ (3)
In the 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; carbon An unsubstituted alkyl group having 1 to 30 carbon atoms or an aralkyl group in which the substituted alkyl group is substituted with at least one aryl group having 6 to 20 carbon atoms; an 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 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, capric 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 carboxylic acid The salt of is preferred. Among such carboxylic acids, formic acid, acetic acid and propionic acid are more preferable.

  The said quaternary ammonium compound may be used individually by 1 type, and may be used in combination of 2 or more type.

  The addition amount of the quaternary ammonium compound is 0.05 to 50 mass ppm in terms of the amount of nitrogen derived from the quaternary ammonium compound represented by the following formula (α) with respect to the crude polymer. Is preferred.

Addition amount of quaternary ammonium compound = P × 14 / Q (α)
In the above formula (α), P represents the concentration (mass ppm) of the quaternary ammonium compound relative to the crude polymer, “14” represents the atomic weight of nitrogen, and Q represents the molecular weight of the quaternary ammonium compound.

  A decomposition removing agent such as a quaternary ammonium compound may be added in advance before the crude polymer is melted, or may be added to the melted crude polymer.

  The decomposition / removal agent may be a combination of ammonia, triethylamine and boric acid compounds, which are known decomposition / removal agents, and a quaternary ammonium compound.

<Lubricant (B)>
The oxymethylene resin composition used to form the polyoxymethylene slide part of this embodiment contains a specific amount of a lubricant (B) that is solid at room temperature as an additive. Moreover, the other additive (C) may be included. In this embodiment, “normal temperature” means 25 ° C.

  In the oxymethylene resin composition, the content of the lubricant (B) is from 1 part by weight to less than 25 parts by weight and preferably from 3 parts by weight to less than 20 parts by weight with respect to 100 parts by weight of (A). More preferably, it is 5 parts by mass or more and less than 10 parts by mass. By making the content of the lubricant (B) within this range, the productivity, operability and durability of the slide part can be improved.

  The melting point of the lubricant (B) is preferably 60 ° C. or higher, more preferably 160 ° C. or higher, and further preferably 200 ° C. or higher. By making the melting point of the lubricant (B) within this range, the productivity, operability and durability of the slide part can be improved. In general, the melting point refers to the temperature at which a solid melts and liquefies, but in addition to this, the melting point in this embodiment refers to a softening point in the case of an amorphous substance and a decomposition point in the case of a thermosetting resin. And Moreover, in this embodiment, melting | fusing point can be measured by the method as described in the below-mentioned Example.

In the oxymethylene resin composition, the dispersed state of the lubricant (B) is preferably uniform. The average dispersed particle diameter D ₅₀ of the lubricant (B) is preferably ₅₀ μm or less, more preferably 30 μm or less, and even more preferably 10 μm or less. Thereby, a slide part having stable physical properties can be obtained. In the present embodiment, the average dispersed particle diameter D ₅₀ of the lubricant (B), for example, using a scanning electron microscope (SEM) from the cutting surface of the member formed from oxymethylene resin composition (I), required A phase in which the particle diameter of the lubricant to be dyed and inspected according to the conditions was photographed at a magnification of 1,000 to 50,000 times, and the maximum diameter of randomly dispersed particles of at least 50 lubricants (B) was randomly selected. Indicates the value of the arithmetic mean.

  Specific lubricants (B) include hydrocarbon lubricants (paraffin wax, olefin wax, etc.), higher fatty acid lubricants (such as stearic acid and palmitic acid), salts of these higher fatty acids, higher alcohol lubricants. (Stearyl alcohol, behenyl alcohol, etc.), fatty acid amides (lauric acid amide, stearic acid amide, etc.), fatty acid esters (ethylene glycol distearate, cetyl myristate, etc.), synthetic resin lubricants, boron nitride, graphite, And molybdenum disulfide.

  As the lubricant (B) used in the present embodiment, a synthetic resin lubricant is particularly preferable. Synthetic resin lubricants include olefin resin lubricants, silicon resin lubricants, fluororesin lubricants, and the like.

  As the olefin resin-based lubricant used in the present embodiment, homopolymers synthesized using simple alkenes such as polyethylene and polypropylene as monomers, copolymers containing several units in the skeleton, and modified parts such as maleic anhydride and glycidyl groups are used. Examples thereof include modified olefins.

  In addition, the silicon resin-based lubricant used in the present embodiment refers to a resin having a structure having a siloxane bond (Si—O—Si) in the main skeleton. For example, a silicone resin, a modified silicone resin having a methyl group, a phenyl group, or a glycidyl group on Si can be used.

  Furthermore, the fluororesin-based lubricant used in the present embodiment refers to a fluorine-containing polyolefin such as a fully fluorinated resin, a partially fluorinated resin, and a fluorinated resin copolymer. Specifically, for example, polytetrafluoroethylene (PTFE), ethylene / tetrafluoroethylene copolymer (ETFE), perfluoroalkoxy fluororesin (PFA), and the like can be given.

  Two or more kinds of the lubricants (B) may be used in combination.

(Other additives (C))
The oxymethylene resin composition used in the present embodiment may contain other conventionally known additives (C) as long as the object of the present embodiment is not impaired.

  Other additives (C) include, for example, antioxidants, heat stabilizers, formaldehyde and formic acid scavengers, weathering (light) agents, lubricants, various inorganic and organic fillers, crystal nucleating agents, mold release agents, pigments・ Appearance improvers such as dyes are listed.

  The content of the additive (C) in the oxymethylene resin composition is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, relative to 100 parts by mass of the polyoxymethylene (A). More preferably, it is 3 parts by mass or less.

(Method for producing oxymethylene resin composition)
The oxymethylene resin composition is a component constituting the polyoxymethylene slide part of the present embodiment, and contains the polyoxymethylene (A) and the lubricant (B) as described above, and further if necessary. It contains the other additive (C). Below, the manufacturing method of the oxymethylene resin composition which contains all the polyoxymethylene (A), a lubricant (B), and another additive (C) is demonstrated exemplarily.

  Mixing of the above polyoxymethylene (A), lubricant (B), and other additives (C) adds the components (B) and (C) during granulation of the polyoxymethylene (A). Alternatively, it may be carried out by melt-kneading.

  Moreover, after granulating (A) component, after newly mixing (A) component-(C) component using a Henschel mixer, a tumbler, and a V-shaped blender, a kneader, a roll mill, a single screw extruder, two An oxymethylene resin composition can also be obtained by melt-kneading using a screw extruder or a multi-screw extruder.

  Moreover, in order to improve the dispersibility of the component (B) and the component (C) with respect to the polyoxymethylene (A), after pulverizing a part or all of the pellets of the polyoxymethylene (A) to be mixed, You may melt-mix. In this case, the dispersibility may be further increased by using a spreading agent. Examples of the spreading agent 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. Furthermore, 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.

(Physical properties of oxymethylene resin composition)
The melt flow rate (MFR) (ASTM 1238, temperature 190 ° C.) of the oxymethylene resin composition used in this embodiment is preferably 2 to 20 g / 10 minutes, more preferably 3 to 15 g / 10 minutes. . Depending on the influence of the addition of the lubricant (B) and other additives (C) on the MFR of the oxymethylene resin composition, the above-mentioned chain transfer agent is converted to 0.02 to 0.02 in terms of 1 mol of formaldehyde. It is preferable to polymerize polyoxymethylene (A) by adding 08 mol%. By setting the MFR of the oxymethylene resin composition within the above range, the productivity of the polyoxymethylene slide parts tends to be maintained, and the operability and durability tend to be improved.

[Method for producing member (I)]
The member (I) used in this embodiment can be obtained, for example, by molding the oxymethylene resin composition described above.

  As a manufacturing method of member (I) used for this embodiment, the various well-known shaping | molding methods using the conventional oxymethylene resin composition used as a raw material are mentioned.

  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. It can be molded by any one of molding methods such as 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 which different materials are combined and in-mold composite molding are 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.

[Rockwell hardness of member (I)]
The member (I) used in this embodiment is formed from the oxymethylene resin composition. The Rockwell hardness (M scale) of this member (I) is 78-98, and preferably 80-95. The slide part including the member (I) having such Rockwell hardness is excellent in operability and durability.

  In this embodiment, the Rockwell hardness (M scale) is a value measured by the method described in the examples described later.

[Partner material (II)]
The slide component made of polyoxymethylene of the present embodiment includes a counterpart material (II) in contact with the member (I) described above.

  The counterpart material (II) used in the present embodiment refers to a material that faces the member (I) when sliding.

  The counterpart material (II) used in the present embodiment has a Rockwell hardness (M scale) of 55 to 120, preferably 60 to 115. The slide component including the counterpart material (II) having such Rockwell hardness is excellent in operability and durability.

  In this embodiment, the Rockwell hardness (M scale) is a value measured by the method described in the examples described later.

  Further, the counterpart material (II) used in the present embodiment is formed using a resin other than the polyoxymethylene resin. Examples of resins other than polyoxymethylene resins include polyamide resins, polypropylene resins, polystyrene resins, nitrile resins, polyester resins, polyphenylene sulfide resins, polyphenylene ether resins, and the like. The resin forming the counterpart material (II) used in the present embodiment is a resin that can form the counterpart material (II) within the specified Rockwell hardness range, and a filler, a flexible material, etc. are added to the resin. Including those granted.

  Among these, a polyamide-based resin or a polyester-based resin is preferable from the viewpoint of durability. The polyamide-based resin is a polymer in which monomers are bonded by an amide bond (—CO—NR—). For example, polyamide 6, polyamide 11, polyamide 12, polyamide 66, polyamide 610, polyamide 6T, polyamide 6I, polyamide 9T , Polyamide M5T, polyamide 612, aramid and the like. Polyester resins are polycondensates of polycarboxylic acids (dicarboxylic acids) and polyalcohols (diols), such as polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate. Etc.

  The counterpart material (II) used in the present embodiment is preferably one using a reinforced resin. In the present embodiment, the reinforced resin refers to a resin obtained by adding a filler to the resin. It is preferable that the counterpart material (II) used in the present embodiment is a reinforced resin in which a filler is added to a polyamide resin or a polyester resin. This filler may contain an inorganic filler or an organic filler or a combination of both.

  Specific examples of the inorganic filler include metal powder (aluminum, stainless steel, nickel, silver, etc.), oxide (silicon oxide, iron oxide, alumina, titanium oxide, zinc oxide, etc.), hydroxide (aluminum hydroxide, Magnesium hydroxide, calcium hydroxide, etc.), silicates (talc, mica, clay, bentonite, etc.), carbonates (calcium carbonate, magnesium carbonate, hydrotalcite, etc.), carbon materials (carbon black, graphite, carbon fiber, etc.) ), Sulfate, boron nitride, silicon nitride and the like.

  Specific examples of the organic filler include natural products (such as linter, wood, rice husk, silk, and leather) and synthetic systems (such as aramid, Teflon (registered trademark), and viscose).

  Among these, it is preferable to select from among fillers that can be added to each conventional resin for maintaining stability, that is, selected from fillers that have been added to the resin and have a proven record as a product. The shape of the filler may be any of powder, scale, plate, needle, sphere, fiber, tetrapod, and the like, and is not particularly limited.

  A known surface treatment agent may be used as the filler in order to improve the affinity with the resin.

  Examples of surface treatment agents include silane coupling agents such as aminosilane and epoxysilane, titanate coupling agents, fatty acids (saturated fatty acids and unsaturated fatty acids), alicyclic carboxylic acids, resin acids, metal soaps, and resins. And the like.

  The addition amount of the filler is preferably 5 to 45% by mass, more preferably 15 to 35% by mass with respect to the resin forming the counterpart material (II).

  One type of filler may be used, or two or more types may be used in combination.

[Manufacturing method of counterpart material (II)]
As a manufacturing method of member (II) used for this embodiment, the various well-known shaping | molding methods using resin other than the polyoxymethylene resin mentioned above used as a raw material are mentioned.

  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. It can be molded by any one of molding methods such as 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 the resin forming the counterpart material (II) is usually molded are used. For example, in the case of a thermoplastic resin, the resin temperature is 10 ° C. or more from the melting point or softening point, and in the range of 10 ° C. or less from the decomposition temperature, and in the case of a thermosetting resin, molding is performed at a curing temperature and a curing time according to the curing agent. Do.

[Usage of Polyoxymethylene Slide Parts]
The slide part made of polyoxymethylene of the present embodiment may be the entire slide part of the apparatus or a part including the slide surface.

  The polyoxymethylene slide part of the present embodiment may have a different material insert and / or a joint with a different material for the purpose of improving workability and functionality. The polyoxymethylene slide part of the present embodiment is formed into a complicated shape or post-processed because the above-described oxymethylene resin composition has excellent productivity and is also excellent in workability. And the operability and durability can be further improved. Further, the surface state of the polyoxymethylene slide part of the present embodiment may be smooth or subjected to various embossing processes.

  The polyoxymethylene slide part of the present embodiment is preferably a slide part used at a steady sliding surface pressure of 20 to 150 MPa between the member (I) and the counterpart material (II). A slide part used at 40 to 120 MPa is preferable. At the time of sliding, the surface pressure of the component (I) and the counterpart material (II) may be constant or fluctuate like sliding with a spring load applied. In addition, the polyoxymethylene slide part of this embodiment is a slide part that is used at a steady sliding linear velocity of 0.08 to 2.3 m / sec between the above-described member (I) and the counterpart material (II). Preferably, it is a slide part used at 0.1 to 2.0 m / sec. The use of the polyoxymethylene slide component of the present embodiment at the preferred sliding surface pressure and / or sliding linear velocity described above can improve the operability and durability. In the present embodiment, the sliding surface pressure refers to the maximum load per unit area when the member (I) is in pressure contact with the opposing material (II) that is constantly opposed. The sliding surface pressure and the sliding linear velocity may vary within a preferable range in the case of steady movement.

  The slide component made of polyoxymethylene of this embodiment is preferably used in a contact form in which the contact surface between the member (I) and the counterpart material (II) is a line or a surface. The contact surface refers to a shape when the member (I) and the counterpart material (II) are in contact with or separated from each other when viewed macroscopically. For example, when the record needle and the record slide, the contact surface becomes a point. The polyoxymethylene slide part of this embodiment may be unsuitable because the contact form is a point and the surface pressure increases, resulting in scratching sliding and severe wear.

  Moreover, it is preferable that the movement at the time of steady sliding of the member (I) or the counterpart material (II) of the slide part is intermittent or intermittent. The movement is how the counterpart material (II) moves as viewed from the member (I). For example, in the above case, the record moves continuously when viewed from the record needle. If the surface pressure and the speed are increased by continuous movement, the polyoxymethylene slide part of this embodiment may become unsuitable because the temperature of the sliding surface rises and wear becomes intense.

  In addition, the sliding form of the contact surface of the slide component is preferably used when contacting continuously / discontinuously, discontinuously / continuously, continuously / continuously. The sliding form means a form in which the contact surface slides continuously or discontinuously. For example, in the above case, the record needle side slides continuously, but the record side slides discontinuously, so it becomes continuous / discontinuous. The polyoxymethylene slide part of the present embodiment may be difficult to obtain the effect when the speed and the surface pressure are reduced in the discontinuous / discontinuous sliding form.

  In the above method of use, the polyoxymethylene slide part of the present embodiment can achieve excellent operability and improved durability.

  In addition, the slide part made of polyoxymethylene according to the present embodiment adjusts the sliding speed by changing the sliding pressure or changing the shape of the sliding surface, and the member (I) or the counterpart material (II ) Can be determined. In particular, the opposing material (II) that opposes the member (I) is not a simple plane in which the sliding direction is perpendicular to the pressure direction, but has protrusions, depressions, irregularities of 1 mm or more, or 3 degrees or more A more remarkable effect can be seen when the inclination is as follows.

  The example of the specific form of the slide component made from polyoxymethylene of this embodiment is shown to FIGS. 1-1-3-2. The member (I) may be either (x) or (y) in FIGS. That is, the member (I) and the member (II) are a combination, and the above may be interchanged.

  Specific applications of slide parts made of polyoxymethylene include washers, spacers, bushes, rotors, pads, swivels, rollers, and parts thereof used in electrical equipment, automotive parts and other various mechanical parts. Is mentioned.

[How to use slide parts made of polyoxymethylene]
The method of using the polyoxymethylene slide part of the present embodiment uses the above-described polyoxymethylene slide part.

  The method of using the polyoxymethylene slide component of the present embodiment includes a member (I) formed using the above-described oxymethylene resin composition, and a counterpart (II) in contact with the member (I). It is the usage method using components, Comprising: It is preferable that the steady sliding surface pressure of a member (I) and a counterpart material (II) shall be 20-150 MPa, Furthermore, it is more preferable to set it as 40-120 MPa. .

  Further, the method of using the polyoxymethylene slide part of the present embodiment includes a member (I) formed using the above-described oxymethylene resin composition and a counterpart material (II) in contact with the member (I). It is a usage method using a slide part including, and it is preferable that the steady sliding linear velocity between the member (I) and the counterpart material (II) is 0.08 to 2.3 m / sec, and further 0 More preferably, it is set to 1 to 2.0 m / sec.

  As for the method for using the polyoxymethylene slide part, it is preferable that the above-mentioned polyoxymethylene slide part operates regularly and intermittently. For example, in slide parts that are used for manual reciprocation, reversible rotation, etc. by manually moving up and down, left and right, or using cams, clutches, electrical forward / reverse rotation, etc. There is a method in which the operation is repeatedly performed and stopped.

  Hereinafter, although a specific Example and a comparative example with this are given and demonstrated, this embodiment is not limited to the following Examples.

  First, the oxymethylene resin composition (P) and the counterpart material (II) that form the member (I) included in the slide part in Examples and Comparative Examples will be described.

[Oxymethylene resin composition (P) forming member (I)]
As raw materials for preparing the oxymethylene resin composition (P), the following polyoxymethylene (A) and lubricant (B) were used.

(raw materials)
<Polyoxymethylene (A)>
As polyoxymethylene (A), polyoxymethylene homopolymer and polyoxymethylene copolymer obtained by the following procedure were used.

-(A-1) Polyoxymethylene homopolymer The polyoxymethylene homopolymer was prepared as follows.

  A jacketed 5 L tank polymerization vessel 1 equipped with a stirrer was filled with 2 L of n-hexane and provided with a circulation line (inner diameter: 6 mm, length: 2.5 m). The n-hexane was circulated at 20 L / hr by a pump. 200 g / hr of dehydrated formaldehyde gas was directly supplied to this circulation line. Further, a catalyst (dimethyl distearyl ammonium acetate) was supplied to a circulation line immediately before the reactor. Furthermore, a chain transfer agent (acetic anhydride) is added to the hexane supplied to compensate for the decrease in the polymerization slurry sent to the next step, and the adjustment is performed within the range of 0.13 to 0.52 g / hr. Polymerization was carried out at 58 ° C. while feeding to a slurry to obtain a polymerization slurry containing a crude polymer. The amounts of the polymerization catalyst and chain transfer agent used were adjusted according to the final product composition.

  Stabilization was performed by reacting the obtained polymerization slurry in a 1: 1 mixture of hexane and acetic anhydride at 140 ° C. for 2 hours and acetylating the molecular ends. The polymer after the reaction was collected by filtration, depressurized to 2 mmHg or less, and dried for 3 hours with a vacuum dryer set at 80 ° C. to obtain a polyoxymethylene homopolymer powder.

  Furthermore, 100 parts by mass of this powder, 0.2 parts by mass of Irganox 245 (manufactured by Ciba Specialty Chemicals Co., Ltd.) and 0.2 parts by mass of H-3 (manufactured by Asahi Kasei Finechem Co., Ltd.) as stabilizers Mix for 1 minute with a Henschel mixer. Thereafter, the obtained mixture was adjusted to a screw rotation speed of 100 rpm with a screw-type twin screw extruder with a vent set to 200 ° C. (BT-30, L / D = 44 manufactured by Plastic Industry Co., Ltd.) at 24 amps. The mixture was melt-kneaded to obtain polyoxymethylene homopolymer pellets. From raw material input to pellet collection, the operation was performed while avoiding oxygen contamination as much as possible.

-(A-2) Polyoxymethylene copolymer The polyoxymethylene copolymer was prepared as follows.

  First, the polymerization process was performed as follows.

  A self-cleaning type biaxial paddle type continuous mixing reactor with a jacket through which a heat medium can pass (screw diameter 3 inches, length ratio to diameter (L / D) = 10) was adjusted to 80 ° C. Trioxane as the main monomer, 3750 g / hr, 1,3-dioxolane as the comonomer, 25-150 g / hr, and methylal as the chain transfer agent (both used for impurities reduction treatment) 2.0-8. Adjustment was made in the range of 0.0 g / hr, and the mixture was continuously fed to the continuous mixing reactor.

In addition, a 1% by mass cyclohexane solution of boron trifluoride di-n-butyl etherate as a polymerization catalyst was added to the continuous mixing reactor so that the catalyst was 2.0 × 10 ⁻⁵ mol with respect to 1 mol of trioxane. Polymerization was carried out by adding to a polymer flake. The amounts of the polymerization catalyst, chain transfer agent and comonomer used were adjusted for each composition as the final product.

  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 polymer flakes was sequentially filtered, washed and dried to obtain a crude polymer.

  Equivalent to an amount of 20 ppm when triethyl (2-hydroxyethyl) ammonium formate is converted into the amount of nitrogen using the following formula (α) as a quaternary ammonium compound with respect to 1 part by mass of the obtained crude polymer. 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 polymer, “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. The obtained dry polymer is added 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 further dried. 0.5 parts by mass of water was added to 100 parts by mass of the polymer. The average residence time was set to 1 minute, and vacuum degassing was performed while stabilizing the polymer ends.

  Next, with respect to 100 parts by mass of the dried polymer, 0.2 parts by mass of Irganox 245 (manufactured by Ciba Specialty Chemicals Co., Ltd.) and H-3 (manufactured by Asahi Kasei Finechem Co., Ltd.) 0.2 as stabilizers. Part by mass was previously mixed with a Henschel mixer for 1 minute. 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 manufactured by Plastic Industry Co., Ltd.) = 44), the screw speed was 100 rpm, and melt kneading was performed at 24 amps to obtain polyoxymethylene copolymer pellets. From raw material input to pellet collection, the operation was performed while avoiding oxygen contamination as much as possible.

  The ratio of the oxyalkylene unit b (mol) to the oxymethylene unit a (100 mol) in the three types of oxymethylene copolymers obtained by adjusting the comonomers (hereinafter also referred to as “b / a”) is shown in Table 1 below. Here, (b / a) was obtained as follows. The obtained polyoxymethylene copolymer was dissolved in a solvent hexafluoroisopropanol (HFIP) -d2 (D conversion rate 97%, Wako Pure Chemicals 98% assay) over 24 hours, thereby producing a polyoxymethylene copolymer. A 1.5% by weight solution of was prepared.

  Using a 1.5% by mass solution of the above polyoxymethylene copolymer as a specimen, using a JEOL-400 nuclear magnetic resonance spectrometer (1H: 400 MHz), under conditions of 55 ° C. and 500 times of integration, oxymethylene unit a, 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.

<Lubricant (B)>
The following (B-1) to (B-5) were used as the lubricant (B).
(B-1): Fluororesin (Lublon L-5, manufactured by Daikin Industries, Ltd., melting point> 200 ° C.)
(B-2): Fluororesin (Lublon L-2, manufactured by Daikin Industries, Ltd., melting point> 200 ° C.)
(B-3): Silicone resin (KMP590, manufactured by Shin-Etsu Chemical Co., Ltd., curable resin, melting point (decomposition temperature)> 200 ° C.)
(B-4): Olefin resin system (Toughmer A70000, manufactured by Mitsui Chemicals, Inc., 160 ° C.> melting point> 60 ° C.)
(B-5): ester type (cetyl myristate, manufactured by NOF Corporation, solid at room temperature, melting point <60 ° C.)
(B-6): Ester system (diisodecyl adipate, manufactured by Daihachi Chemical Industry Co., Ltd., liquid at normal temperature)
The melting point of the lubricant (B) was measured with a differential scanning calorimeter (DSC measuring device: STA6000 manufactured by Perkin Elmer). The temperature of the solid lubricant at room temperature was raised from room temperature to 200 ° C. at 2.5 ° C./min. The exothermic peak when the horizontal axis represents temperature and the vertical axis represents heat flow was defined as the melting point.

(Preparation of oxymethylene resin composition (P))
Said raw materials (A) and (B) etc. were mix | blended according to the composition shown in following Table 1, and were mixed uniformly using the Henschel mixer. The obtained mixture was melt-mixed using 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 granulation was performed. Then, pellets of the oxymethylene resin compositions (P1) to (P19) were obtained.

  The melt flow rate (MFR) of the oxymethylene resin compositions (P1) to (P19) is shown in Table 1 below. Adjustment of MFR in the oxymethylene resin compositions (P1) to (P19) was performed by controlling the addition amount of the chain transfer agent and the lubricant (B) when preparing the raw material (A). Here, MFR was determined as follows.

  About the pellet of the obtained oxymethylene resin composition (P1)-(P19), melt flow rate (ASTM 1238, temperature 190 degreeC) was measured using the melt indexer (Toyo Seiki Co., Ltd. product, F-W01). .

The productivity of the oxymethylene resin composition pellets was evaluated by the following method. The evaluation results are shown in Tables 2-4.

<Productivity evaluation of oxymethylene resin composition>
The productivity evaluation of the oxymethylene resin composition was carried out by adjusting the average granulation amount per unit time of the oxymethylene resin composition when the granulation was carried out by adjusting the extruder torque to be constant at 25 amperes. It was performed comprehensively according to the condition, appearance and odor of the pellets.

  As evaluation criteria, it was defined as follows in comparison with the evaluation of productivity when the oxymethylene resin composition P1 containing no lubricant was passed through an extruder.

  Compared with the productivity evaluation of the oxymethylene resin composition P1 containing no lubricant, the case where it is good is ◯, the case where it is the same level is ◇, the case where it is slightly lowered is △, the case where it is clearly lowered is × As a result, productivity evaluation of each oxymethylene resin composition was performed.

  In addition, said "good" means the state where the increase in the average granulation amount per unit time was 10% or more when compared with the oxymethylene resin composition P1.

  The above “slightly reduced” means that the average granulated amount per unit time is within 20% to 40% when compared with the oxymethylene resin composition P1, and the resulting strand is stable without blistering or breaking. The pellets thus obtained can be wound up, and the resulting pellets have a slight facet and have an odor but do not deteriorate the workability.

  The above “obviously reduced” means that when compared with the oxymethylene resin composition P1, a decrease in average granulation amount per unit time is larger than 40%, or a biting defect or strand breakage occurs. This is the case where the removal has become unstable, or the appearance (color or shape) of the pellet is bad, or the odor of the pellet is strong, which affects workability.

[Resin forming the counterpart material (II)]
The following resins were used as the resin for forming the counterpart material (II).
(B-1): Polyamide / GF 30% (Leona 14G33, manufactured by Asahi Kasei Chemicals Corporation)
(B-2): Polyester / GF 30% (Novaduran 5010G30, manufactured by Mitsubishi Engineering Plastics)
(B-3): Epoxy resin (EP4100, manufactured by Adeka Corporation / curing agent EH101)
(B-4): Polyoxymethylene resin (Tenac C4520, manufactured by Asahi Kasei Chemicals Corporation)
(B-5): Polyethylene (Suntech M7620, manufactured by Asahi Kasei Chemicals Corporation)
(B-6): Phenolic resin (AV Light 811, manufactured by Asahi Organic Materials Co., Ltd./hardening agent paraform)
[Formation of mating material (II)]
Using the resins (b-1) to (b-6) as the counterpart material (II), the counterpart materials (II-1) to (II-6) were formed as follows.

-Formation of counterpart material (II-1) Using the resin (b-1), the counterpart material (II-1) was formed by a heat press as follows. The heating press was carried out using a heating press (manufactured by Sansho Industry Co., Ltd., two-stage heater press) at a press temperature of 280 ° C., a press pressure of 20 MPa, and a press time of 15 seconds. After the heating press, the plate was cooled at 80 ° C. for 45 seconds, and the obtained flat plate (thickness 3 mm) was used as the counterpart material (II-1). The counterpart material (II-1) had a Rockwell hardness (M scale) of 110.

  In this example, the Rockwell hardness (M scale) was measured using a hardness meter (ATK-F3000, manufactured by Akashi Seisakusho Co., Ltd.) by stacking two flat plates obtained by the heating press.

-Formation of mating material (II-2) Using the resin (b-2), except that the pressing temperature was 255 ° C and the cooling temperature after pressing was 90 ° C, the same as the mating material (II-1). Thus, a counterpart material (II-2) was obtained. The counterpart material (II-2) had a Rockwell hardness (M scale) of 105.
-Formation of counterpart material (II-3) The above-mentioned resin (b-3) was heated with a curing agent and premixed, and then the counterpart material (except for the press temperature of 120 ° C and the press time of 10 hours). The counterpart material (II-3) was obtained in the same manner as the formation of II-1). The counterpart material (II-3) had a Rockwell hardness (M scale) of 110.

-Formation of counterpart material (II-4) Using the resin (b-4), except that the press temperature was 200 ° C and the cooling temperature after press was 70 ° C, the same as the formation of the counterpart material (II-1) Thus, a counterpart material (II-4) was obtained. The counterpart material (II-4) had a Rockwell hardness (M scale) of 81.

-Formation of mating material (II-5) Using the resin (b-5), except that the pressing temperature was 200 ° C and the cooling temperature after pressing was 40 ° C, the same as the mating material (II-1). Thus, a counterpart material (II-5) was obtained. The counterpart material (II-5) had a Rockwell hardness (M scale) of 40.

-Formation of counterpart material (II-6) The above-mentioned resin (b-6) was used, except that after heating with a curing agent and premixing, the press temperature was 210 ° C and the press time was 10 hours. In the same manner as in the formation of II-1), a counterpart material (II-6) was obtained. The counterpart material (II-6) had a Rockwell hardness (M scale) of 125.

[Rockwell hardness of member (I)]
Using the pellets of the oxymethylene resin composition shown in Table 1, a flat plate was molded in the same manner as the counterpart material (II-4), and the Rockwell hardness was measured. The measurement results are shown in Table 1. Since the oxymethylene resin compositions (P5) and (P6) were not excellent in productivity, the Rockwell hardness was not measured.

[Example 1]
As a member (I) formed using the oxymethylene resin composition, a slide pin (Ia) is prepared as follows, and the following guide part (IIb) is used as a counterpart material (II) in contact with the member (I). It produced as follows.

(Production of slide pin (Ia))
Using the oxymethylene resin composition (P2) prepared above, a slide pin (Ia) was produced by injection molding as follows.

  The injection molding was performed using an injection molding machine (TI-30G, manufactured by Toyo Machine Metal Co., Ltd.) with a cylinder temperature of 200 ° C. and a mold temperature of 80 ° C. as a guide.

  As shown in FIG. 4-3, the dimensions of the slide pin (Ia) were a semicircular cylinder with a diameter of 5 mm, a width of 5 mm, and a slide pin length of 15 mm.

(Quality evaluation of slide pin (Ia))
The quality evaluation of the slide pin (Ia) produced using the oxymethylene resin composition was comprehensively performed by visually checking the appearance (silver, flow mark, etc.) and coloring of the molded product.

  The evaluation criteria are ○ when the mold transferability is good and the appearance such as smoothness and glossiness is good, ○ the case equivalent to Comparative Example 1 that does not contain a lubricant, and some defects such as silver and flow mark The evaluation was made with Δ when the defect was confirmed, and x when the defect was clearly confirmed on the sliding surface. Evaluation took the average of five of the produced slide pins (Ia). The evaluation results are shown in Table 2.

(Production of guide part (IIb))
A strip of 25 mm × 30 mm was cut out from the formed counterpart material (II-1), and the strip was fixed to a SUS jig of a slide component evaluation device described later to be a guide portion (IIb).

(Production of slide parts)
Using the slide pin (Ia) and the guide part (IIb) produced as described above, a slide part having a configuration as shown in FIG. 4-1 was produced. The slide part was evaluated as follows.

(Evaluation of productivity of slide parts)
The evaluation of the productivity of the slide part was performed based on the productivity of the oxymethylene resin composition described above and the quality evaluation of the slide pin (Ia) described above. The evaluation results are shown in Table 2.

(Evaluation of operability and durability of slide parts)
The evaluation of the operability and durability of the slide part was performed using a slide part evaluation apparatus described later. The sliding surface pressure between the slide pin (Ia) and the guide part (IIb) during the evaluation is 80 MPa, and the sliding linear velocity between the slide pin (Ia) and the guide part (IIb) is 1.0 m. Per second. In this example, the sliding surface pressure was measured with an existing pressure-sensitive paper (manufactured by Fuji Film Co., Ltd., prescale) before starting evaluation of the slide parts. The sliding linear velocity was measured with a tachometer (manufactured by Ono Sokki Co., Ltd., HT5500).

[Slide parts evaluation system]
FIGS. 4-1 to 4-3 show the slide component evaluation apparatus used for evaluating the operability and durability of the slide component.

  FIG. 4A is a schematic diagram of the slide component evaluation apparatus. As shown in FIG. 4A, the slide component evaluation apparatus includes a slide pin (Ia) and a guide portion (IIb). A load was applied from the upper part of the slide pin (Ia), and the guide part (IIb) was reciprocated in the longitudinal direction. 4-2 shows a front view and dimensions of the guide portion (IIb), and FIG. 4-3 shows a front view and dimensions of the slide pin (a).

  For the evaluation of slide parts, a reciprocating tester (AFT-15MS manufactured by Tokyu Seimitsu Co., Ltd.) was improved, and the motor capacity and load resistance were increased so that evaluation under each condition of this example was possible. Using. The measurement conditions were a reciprocating distance of 20 mm, an environmental temperature of 23 ° C., and a humidity of 50%. The load was balanced at the center position of the guide portion (IIb).

(Evaluation criteria for operability and durability)
The operability of the slide parts was evaluated by observing the operation state (sound generation and slide pin movement) when the slide test was started.

  The durability of the slide component was evaluated by observing changes (shape change and appearance) between the slide pin and the guide portion when a long-term slide test was performed. Specifically, the operability and durability of the slide parts were evaluated as follows.

<Operability>
About the generation | occurrence | production of a sound and the movement of a slide pin, when reciprocating 1 to 10 times from the start of a reciprocation test was observed. Each test was performed three times and evaluated by averaging.

  About generation | occurrence | production of a sound, it listened from the distance of 30 cm from the sliding part of a slide component evaluation apparatus, and it evaluated as follows by confirming the presence or absence of a sound. When no sound was generated, ◎, when the sound was generated within 5 times, ◯, when a short sound was always confirmed ◇, and when a large continuous sound was always confirmed, ×. The evaluation results are shown in Table 2.

  The evaluation criteria for the movement of the slide pin are as follows: Smooth operation from the first time ◎ Smooth operation within 5 times, ◎ Stick stick confirmed ◇ Always confirm stick slip The case where it was done was set as x. The evaluation results are shown in Table 2.

<Durability>
In addition, the durability of the slide parts was evaluated by observing changes in the shape of the slide pins and the appearance of the slide pins and guide portions when the reciprocating test was performed 100,000 times.

  The observation of the shape change was performed using a microscope (VHX-1000, manufactured by Keyence Corporation). The case where the wear amount of the slide pin is 20 μm or less is indicated by ◎, the case where it exceeds 20 μm and 35 μm or less is indicated by ◯, the case where it exceeds 35 μm and is 50 μm or less is indicated by ◇, and the case where it is greater than 50 μm is indicated by ×. The evaluation results are shown in Table 2.

  Regarding the appearance observation, the evaluation was made with ◎ when it was very good, ◯ when it was very good, ◇ when it was good, and × when it was bad. The evaluation results are shown in Table 2.

  The above “very good” refers to a state in which almost no peeling or the like was observed on the slide pin and the guide part. The above “very good” means a state in which the slide pin and / or the guide part is peeled off but almost no powder is generated. The above “good” means a state in which the slide pin and / or the guide part are peeled off, but the generation of powder is small. The term “defective” refers to a state in which the slide pin and / or the guide part has been peeled off, and further generation of powder has occurred.

[Examples 2 and 3 and Comparative Examples 1 and 2]
A slide pin (Ia), a guide part (IIb), and a slide part were produced and evaluated in the same manner as in Example 1 except that the oxymethylene resin composition of the type shown in Table 2 was used. The evaluation results are shown in Table 2. In Comparative Example 2, since a nonuniform portion was clearly confirmed in the appearance of the sliding surface in the slide pin (Ia), the subsequent evaluation was not performed.

As shown in Table 2 above, from the evaluation results of Examples 1 to 3 and Comparative Examples 1 and 2, a slide part made of polyoxymethylene using an oxymethylene resin composition containing a lubricant defined in this embodiment, It was found that high productivity can be maintained, and excellent operability and durability. It was found that the slide part using the oxymethylene resin composition not containing the prescribed lubricant in this embodiment is inferior in operability and durability.

  In addition, when an oxymethylene resin composition having a lubricant content larger than specified in this embodiment is used, surging or strand breakage occurs in the extruder, and color unevenness is confirmed on the polyoxymethylene slide parts. It was found that the quality was inferior and the productivity decreased.

[Comparative Example 3]
A slide pin (Ia), a guide part (IIb), and a slide part were produced in the same manner as in Example 1 except that the oxymethylene resin composition of the type shown in Table 2 was used, and each evaluation was attempted. . However, in Comparative Example 3, in the production of the pellet (P6) of the oxymethylene resin composition, since the biting failure or the strand was cut and the winding became unstable, the production of the slide pin (Ia) and the subsequent steps Was not evaluated.

  As shown in Table 2 above, from the evaluation results of Example 2 and Comparative Example 3, a slide part including a member formed using the oxymethylene resin composition containing a solid lubricant at room temperature according to this embodiment is It was found that high productivity can be maintained. It has been found that even when the same amount of lubricant at liquid temperature as that of the lubricant of this embodiment is fed, surging occurs and the productivity is remarkably lowered due to poor biting.

[Examples 4 and 5 and Comparative Examples 4 to 6]
A slide pin (Ia) and a slide part were produced in the same manner as in Example 2 except that the guide part (IIb) was produced from the counterpart materials (II-2) to (II-6) as shown in Table 2. Each evaluation was conducted. The evaluation results of Examples 4 and 5 and Comparative Examples 4 to 6 are shown in Table 2.

  As shown in Table 2, from the evaluation results of Examples 2, 4, and 5 and Comparative Examples 4 to 6, it was formed using a resin other than polyoxymethylene resin, and the Rockwell hardness (M scale) was 55 to 120. It was found that the slide parts using the mating material had excellent operability and durability.

  Both the sound and the stick slip were confirmed in the operability evaluation of the slide part using the counterpart material formed from polyoxymethylene resin (POM). In addition, slide parts using a mating material softer than the prescribed Rockwell hardness had a change in appearance, such as peeling at the guide part after completion of the slide test, and further generation of dents and powder in the guide part. . In addition, the slide part using the counterpart material harder than the prescribed Rockwell hardness showed a large change in the shape of the slide pin, and further, a part of the slide pin was peeled off.

  Among the counterpart materials specified in the present embodiment, it has been found that the counterpart material formed from reinforced resin is particularly preferable from the balance of operability and durability.

[Comparative Examples 7 and 8]
In Comparative Example 7, an oxymethylene resin composition (P16) in which 3 parts by mass of an elastomer (Perprene P30B: manufactured by Toyobo Co., Ltd.) was added to the oxymethylene resin composition (P2) as another additive was used. In Comparative Example 8, an oxymethylene resin composition (P17) in which 25 parts by mass of glass fiber (ECS03T-851: manufactured by Nippon Electric Glass Co., Ltd.) was added as an additive to the oxymethylene resin composition (P2). . Other than that was carried out similarly to Example 1, and produced the slide pin (Ia), the guide part (IIb), and the slide component, and implemented each evaluation. The evaluation results of Comparative Examples 7 and 8 are shown in Table 2.

  As shown in Table 2, from the evaluation results of Examples 1 and 2 and Comparative Examples 7 and 8, the member (I) having a Rockwell hardness (M scale) of the polyoxymethylene resin composition of 78 to 98 was used. The slide parts have been found to have excellent productivity and durability. From this, it was suggested that the balance of hardness of member (I) and counterpart material (II) is important.

[Examples 6 to 9]
A slide pin (Ia), a guide part (IIb), and a slide part were produced in the same manner as in Example 1 except that the oxymethylene resin composition of the type shown in Table 3 was used, and each evaluation was performed. The evaluation results of Examples 6 to 9 are shown in Table 3.

As shown in Table 3 above, from the evaluation results of Example 2 and Examples 6 to 9, the slide part including the member formed using the preferred MFR oxymethylene resin composition of the present embodiment has improved productivity. It can be maintained and has been found to have excellent operability and durability. When the MFR of the oxymethylene resin composition was low, the productivity showed a tendency to decrease, and when it was high, the part of the guide part tended to peel.

[Examples 10 to 12]
A slide pin (Ia), a guide part (IIb), and a slide part were produced in the same manner as in Example 1 except that the oxymethylene resin composition of the type shown in Table 3 was used, and each evaluation was performed. The evaluation results of Examples 10 to 12 are shown in Table 3.

  As shown in Table 3 above, from the evaluation results of Example 2 and Examples 10 to 12, a slide including a member formed using a polyoxymethylene-containing composition in which the preferred comonomer amount of this embodiment is inserted It has been found that the parts can maintain high productivity and have excellent operability and durability. When the amount of inserted comonomer was large, the shape change of the slide pin tended to increase.

[Examples 13 to 16]
A slide pin (Ia), a guide part (IIb), and a slide part were produced in the same manner as in Example 1 except that the oxymethylene resin composition of the type shown in Table 3 was used, and each evaluation was performed. Table 3 shows the evaluation results of Examples 13 to 16.

  As shown in Table 3 above, from the evaluation results of Example 2 and Examples 13 to 16, the slide part including the member formed using the oxymethylene resin composition containing the preferred lubricant of this embodiment is high. It was found that productivity can be maintained, and excellent operability and durability are achieved. When a lubricant having a low melting point was used, the operability of the slide part was improved, but the durability of the slide part tended to decrease less. In addition, surging in the extruder, strand breakage, and silver etc. were confirmed in the slide pin, and the productivity tended to decrease.

[Examples 17 to 20]
The slide pin is the same as in Example 2 except that the sliding surface pressure between the slide pin (Ia) and the guide portion (IIb) when the operability and durability are evaluated is changed as shown in Table 4. (Ia), a guide part (IIb), and a slide part were produced and evaluated. The evaluation results of Examples 17 to 20 are shown in Table 4.

As shown in Table 4 above, from the evaluation results of Example 2 and Examples 17 to 20, excellent operability was achieved by using a polyoxymethylene slide part within the preferable sliding surface pressure range of this embodiment. And was found to be durable. When the sliding surface pressure decreases, the slide pin tends to move less smoothly, and when the sliding surface pressure increases, the sound tends to be generated.

[Examples 21 to 24]
The slide pin (Ia) and the guide portion (IIb) at the time of evaluating operability and durability were changed in the same manner as in Example 2 except that the sliding linear velocity was changed as shown in Table 4. (Ia), a guide part (IIb), and a slide part were produced and evaluated. Table 4 shows the evaluation results of Examples 21 to 24.

  As shown in Table 4 above, from the evaluation results of Example 2 and Examples 21 to 24, in this embodiment, by using a polyoxymethylene slide part within a preferable sliding linear velocity range, excellent operation is achieved. It has been found that it exhibits high performance and durability. When the sliding linear velocity is decreased, the slide pin tends to be unsmooth, and when the sliding linear velocity is increased, noise is generated.

  The present invention relates to one or more slide parts selected from the group consisting of washers, spacers, bushes, rotors, buds, swivels, rollers, etc., and parts thereof in electrical equipment, automobile parts and other various mechanical parts. As an industrial applicability.

Claims (11)

The member (I) formed using the oxymethylene resin composition is a slide component that contacts the counterpart material (II),
The oxymethylene resin composition contains 100 parts by mass of polyoxymethylene (A) and 1 part by mass or more and less than 25 parts by mass of a solid lubricant (B) at room temperature,
The member (I) has a Rockwell hardness (M scale) of 78 to 98,
The polyoxymethylene slide part, wherein the counterpart material (II) is formed using a resin other than oxymethylene resin and has a Rockwell hardness (M scale) of 55 to 120.   The slide part made of polyoxymethylene according to claim 1, wherein the melt flow rate (MFR) of the oxymethylene resin composition is 2 to 20 g / 10 minutes.   3. The polyoxymethylene according to claim 1, wherein the polyoxymethylene (A) contains 0 to 1.35 mol of a comonomer unit other than the oxymethylene unit with respect to 100 mol of the oxymethylene unit. Methylene slide parts.   The slide part made of polyoxymethylene according to any one of claims 1 to 3, wherein the lubricant (B) has a melting point of 60 ° C or higher.   The melting point of the lubricant (B) is 200 ° C or higher, and the polyoxymethylene slide part according to any one of claims 1 to 4.   The said oxymethylene resin composition contains 100 mass parts of polyoxymethylene (A), and 5 mass parts or more and less than 10 mass parts of solid lubricant (B) at normal temperature of Claims 1-5 characterized by the above-mentioned. The slide component made of polyoxymethylene according to any one of the above.   The slide member made of polyoxymethylene according to any one of claims 1 to 6, wherein the counterpart material (II) uses a reinforced resin.   A method for using a slide part made of polyoxymethylene according to claim 1, wherein the slide part made of polyoxymethylene according to claim 1 is used. A method of using a slide component comprising a member (I) formed using an oxymethylene resin composition and a counterpart material (II) in contact with the member (I),
9. The method of using a polyoxymethylene slide part according to claim 8, wherein a steady sliding surface pressure between the member (I) and the counterpart material (II) is 20 to 150 MPa. A method of using a slide component comprising a member (I) formed using an oxymethylene resin composition and a counterpart material (II) in contact with the member (I),
The slide part made of polyoxymethylene according to claim 8 or 9, wherein a steady sliding linear velocity between the member (I) and the counterpart material (II) is 0.08 to 2.3 m / sec. How to use.   The method for using a polyoxymethylene slide part according to any one of claims 1 to 7, wherein the polyoxymethylene slide part according to any one of claims 1 to 7 operates regularly and intermittently.