WO2005003233A1

WO2005003233A1 - Sliding parts made of polyacetal resin

Info

Publication number: WO2005003233A1
Application number: PCT/JP2004/009871
Authority: WO
Inventors: Sachio Anada
Original assignee: Polyplastics Co., Ltd.
Priority date: 2003-07-08
Filing date: 2004-07-05
Publication date: 2005-01-13
Also published as: JP2005029713A; KR101054589B1; TW200504143A; JP4563004B2; KR20050006061A; TWI339670B; CN100339438C; CN1576312A; DE112004001229T5

Abstract

A sliding part improved in sliding characteristics while retaining excellent mechanical properties and moldability inherent in polyacetal resin. Namely, a sliding part made of a composition comprising (A) 100 parts by weight of a polyacetal resin, (B) 0.05 to 20 parts by weight of a lubricating oil taking the form of a liquid at 200°C, and (C) 1 to 20 parts by weight of a core-shell polymer having both a core made of a rubbery polymer and a shell made of a glassy polymer consisting of a vinyl copolymer having oxygen-containing polar groups is reduced in the contact area in sliding by virtue of its being a molded article having a matte surface, thus exhibiting excellent sliding characteristics.

Description

Description Polyacetal resin sliding parts TECHNICAL FIELD OF THE INVENTION

The present invention relates to a sliding component made of a polyacetal resin composition. More specifically, the present invention relates to a sliding component which retains excellent mechanical properties, moldability, and the like inherently possessed by a polyacetal resin, and has more excellent sliding characteristics. Background art

Polyacetal resin has well-balanced physical properties and has excellent sliding properties as a resin, so it is widely used as sliding parts for automobiles, electrical and electronic products, office equipment, building materials, etc. I have. However, as their applications have expanded, so has the demand for sliding characteristics, and further improvements in sliding characteristics and long-term sustainability are required.

There have been attempts to blend various lubricating oils with polyacetal resins for the purpose of improving slidability in response to such demands. For example, a method of adding a fatty acid ester to a polyacetal resin (for example, see Japanese Patent Publication No. 53-1991), a method of adding a silicone oil and a silicone gum to a polyacetal resin (for example, Japanese Patent Publication No. 57-101) A method of adding a silicone oil having a viscosity of 150, OOOcSt or more to the polyacetal resin (see, for example, Japanese Patent Publication No. 63-2777263). A method of adding a silicone oil and an ester lubricant (see, for example, Japanese Patent Publication No. 3-69378) is mentioned.

However, lubricating oils such as silicone oils generally have extremely poor compatibility and affinity with polyacetyl resin, so it is extremely difficult to formulate them. In order to satisfy the demand, it is necessary to add a certain amount of oil, but even if such a composition can be prepared, when it is molded, the oil is easily stained on the resin surface, and its lubrication The action causes slippage between the resins or between the resin and the screw, resulting in poor biting into the molding machine, poor plasticization, and the like, making processing impossible in severe cases. In addition, there is also a disadvantage that the oil is easily stained and sticky to the surface of the molded product, thereby lowering the commercial value. Therefore, when lubricating oil is added for the purpose of improving sliding, it is ideally desirable to reduce the amount of lubricating oil added.

Therefore, for the purpose of remedying the above drawbacks, various studies have been made on the addition of a third substance as a holding material together with the lubricating oil. For example, activated carbon, graphite and the like can be cited as inorganic holding materials, and high molecular weight polyethylene and the like can be cited as organic polymer materials. However, activated carbon, graphite, and the like have low ability to adsorb and retain lubricating oil, and high molecular weight polyethylene and the like also have poor affinity for lubricating oil, and therefore have low beam retention power, which is a practically satisfactory effect. Not obtained. Further, in some cases, the third component may deteriorate the slidability.

On the other hand, various attempts have been made to mix specific core-shell polymers with polyacetal resins. A method of adding a core shell polymer having a core of a rubbery polymer and a shell of a glassy polymer and a polyhydric alcohol fatty acid ester to a polyacetal resin (see, for example, JP-A-6-107758); A core-shell polymer having a glassy polymer shell consisting of a vinyl-based copolymer having a core of a rubber-like polymer, a vinyl-based copolymer having an oxygen-containing polar group, and 2 to 8 carbon chains adjacent to the polyacetal resin A method of adding an oxyalkylene polymer (for example, see Japanese Patent Application Laid-Open No. 6-29047), a core-shell polymer having a rubber-like polymer core and a glass-like polymer shell in a polyacetylene resin. A method of adding a lubricant (for example, see Japanese Patent Application Laid-Open No. Hei 6-107579), a method of adding a rubber-like polymer core and a glassy polymer to a high-molecular-weight polyacetal resin. Core shell with mer shell A method of adding a polymer and a silicone oil (for example, see Japanese Patent Application Laid-Open No. 2000-265360) and the like can be mentioned. Disclosure of the invention

However, these prior documents are written for the purpose of improving impact resistance, fluidity, or weather resistance, but are not written for the purpose of improving slidability. As described above, conventionally known methods cannot provide a sliding part made of a polyacetone resin composition having good workability and excellent sliding properties in a short term and a long term. Further improvements have been desired.

The present inventors have conducted intensive studies in order to respond to the strong demands, and as a result, by forming a sliding component from a resin composition in which a lubricating oil and a specific core-shell polymer are blended with polyacetyl resin, the sliding component is formed. The present invention has been found that the surface of the molded part of the moving part is in an opaque state, the contact area during sliding is reduced, and excellent sliding characteristics are generated. That is, the present invention includes (B) 0.05 to 20 parts by weight of a lubricating oil having a liquid form at 200 ° C., and (C) a rubbery polymer core with respect to (A) 100 parts by weight of a polyacetal resin. A sliding component comprising a polyacetal resin composition comprising 1 to 20 parts by weight of a core-shell polymer having a shell of a glassy polymer composed of a vinyl copolymer having an oxygen polar group.

The present invention also provides a use of the above-mentioned polyacetal resin composition as a sliding part or an article transfer apparatus in which a plurality of the above-mentioned sliding parts are used and arranged so that their central axes are parallel. I do. Detailed description of the invention

Hereinafter, the present invention will be described in detail. First, polyacetal used in the present invention evening - Le resin (A), a high amount that a predominant constituent units Okishimechiren group (-CH ₂ 0-) The compound may be any of polyacetal homopolymer, polyacetal copolymer (including block copolymer) having a small amount of other structural units in addition to oxymethylene groups, and Yuichii polymer. It may have a structure. Also, two or more kinds of polyacetal resins having different characteristics can be blended and used.

In the present invention, among such polyacetal resins, polyacetal copolymers obtained by copolymerizing a comonomer component in an amount of 1 to 30% by weight, particularly 1 to 5% by weight, are preferred, and thus, excellent heat stability is obtained. And moldability can be maintained. It is known that various cyclic ether compounds or cyclic formal compounds can be used as one comonomer component used in the production of polyacetal copolymer, and the comonomer is not particularly limited. Oxide, 1,3-dioxolan, diethylene glycol formal, 1,4-butanediol formal, 1,3-dioxane, propylene oxide and the like.

Next, the lubricating oil used as the component (B) in the present invention has a liquid form at 200 ° C. That is, at a temperature of about 190 to 220 ° C. used for forming polyacetal, it can be in a state of night or close to it.

The lubricating oil used in the present invention is based on one or more selected from the group consisting of silicone oils, polyalkylene glycols, a-olefin oligomers, paraffin oils, alkyl-substituted diphenyl ethers, and fatty acid esters. It is preferable to use a lubricating oil as a lubricant, and particularly preferable are a silicone oil-based lubricating oil, a fatty acid ester-based lubricating oil, and a one-year-old olefin oligomer-based lubricating oil. Here, as the silicone oil, polydimethylsiloxane, polymethylphenylsiloxane, and the like represented by the structure of the following formula (1) are preferably used. RRR

I I I

R— S ί O— (— S i — O—) _n — S u R (1)

I I I

R R R

(Where R is a methyl group, some of which may be an alkyl group, a phenyl group, a halogenated alkyl group, a halogenated phenyl group, etc.)

The viscosity of the silicone oil used in the present invention is not particularly limited.However, considering the slidability and its durability, dispersibility of the oil in the resin, workability during melt-kneading and molding, etc. 100 ~ 100, OOOcSt (25 ° C) is preferred. In the present invention, it is also possible to use a mixture of two or more types of silicone oils having different structures or different viscosities. Is also possible.

The one-year-old olefin oligomer is an aliphatic hydrocarbon having a structure in which a one-year-old fin having C6 to C20 is mainly polymerized or a copolymer of ethylene and a C3-(: 20 α-olefin is copolymerized. In the above, an ethylene * polyolefin oligomer having a number average molecular weight of 400 to 4,000 is preferably used.

Fatty acid esters are esters of monohydric or polyhydric aliphatic alcohols with monohydric saturated or unsaturated fatty acids or dibasic acids.Practically preferred are saturated fatty alcohols having 16 or more carbon atoms. An ester with a saturated fatty acid having 16 or more carbon atoms or a polybasic acid. Examples of the saturated aliphatic alcohol having 16 or more carbon atoms include cetyl alcohol, stearyl alcohol, isostearyl alcohol, behenyl alcohol, erucyl alcohol, hexyldecyl alcohol, and octyldodecyl alcohol. Fatty acids having 16 or more carbon atoms include linear chains such as palmitic acid, stearic acid, isostearic acid, arachidic acid, behenic acid, and montanic acid. Or a branched fatty acid. Either such a monovalent fatty acid and a monovalent aliphatic alcohol ester can be preferably used. Examples of the dibasic acid that forms an ester by bonding to the aliphatic alcohol having 16 or more carbon atoms include phthalic acid, adipic acid, sebacic acid, and trimellitic acid. Such an ester composed of a dibasic acid and an aliphatic alcohol is preferably a full ester in order to maintain the thermal stability of the polyacetal. Among these aliphatic esters composed of a carboxylic acid and an alcohol, particularly preferred are stearyl stearate, behenyl behenate, distearyl dipate, in view of price, ease of acquisition (synthesis, purification), and friction and wear characteristics. And distearyl phthalate. In the present invention, one or more selected from these aliphatic esters are preferably used.

In the present invention, the lubricating oil (B) is blended in an amount of 0.05 to 20 parts by weight based on 100 parts by weight of the polyacetal resin (A), and exhibits an effect of improving the friction and wear characteristics. When the amount is less than 0.05 part by weight, the effect of reducing the friction coefficient is not sufficiently exhibited, and when the amount exceeds 20 parts by weight, the moldability and the frictional characteristics are extremely deteriorated, which is not preferable. Particularly preferably, it is 0.5 to 5 parts by weight.

Next, the core-shell polymer (C) used in the present invention has a rubber-like polymer core and a glass-like polymer shell composed of a vinyl copolymer having an oxygen-containing polar group. Such a core-shell polymer (C) is generally obtained by a continuous multi-stage emulsion polymerization method in which a polymer in a previous stage is successively coated with a polymer in a later stage, in general, in a side emulsion polymerization method. .

When the core-shell polymer has an intermediate phase as described later, the intermediate phase is formed by a multi-stage emulsion polymerization method in which the polymer at the later stage enters the polymer at the earlier stage. There is also. At the time of particle-generating polymerization, it is preferable to start the emulsion polymerization reaction by adding a monomer, a surfactant and water to a reactor, and then adding a polymerization initiator. The first stage of polymerization is a reaction that forms a rubbery polymer. The

Examples of the monomer constituting the rubbery polymer which is the core of the core-shell polymer (C) used in the present invention include a conjugated gen or an alkyl acrylate having an alkyl group having 2 to 8 carbon atoms or a mixture thereof. Can be These monomers are polymerized to form a rubbery polymer. Examples of such a conjugated diene include butadiene, isoprene, and chloroprene. Examples of the alkyl acrylate having an alkyl group having 2 to 8 carbon atoms include, for example, ethyl acrylate, propyl acrylate, butyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, and the like. I can list them. Butyl acrylate is particularly preferably used as the rubbery polymer. In the first stage of polymerization, copolymerizable monomers such as co-gen and alkyl acrylate, for example, aromatic vinyls such as styrene, vinyltoluene, and para-methylstyrene, aromatic vinylidene, acrylonitrile, and methacrylonitrile It is also possible to copolymerize vinyl cyanide, vinylidene cyanide, alkyl methacrylate such as methyl methacrylate, and butyl methacrylate.

The shell phase is formed of a glassy polymer composed of a vinyl copolymer having an oxygen-containing polar group. The oxygen-containing polar group, for example, a hydroxyl group, a group that have a ether bond (e.g., glycidyl group), an amido group (- C0NH-), and although a nitro group (N0 _2), and the like, in particular hydroxyl group and an ether bond Is preferred. A core-shell polymer having no oxygen-containing polar group in the shell phase has almost no matting effect, and does not have the effect of improving the sliding properties of the sliding component comprising the polyacetal resin composition, which is the object of the present invention.

As a monomer constituting the vinyl copolymer having an oxygen-containing polar group, for example, a (meth) acrylate of an alcohol having two or more oxygen-containing polar groups in a molecule is used. Here, an alcohol having two or more oxygen-containing polar groups in the molecule Represents an alcohol having at least one oxygen-containing polar group in addition to the hydroxyl group of the alcohol moiety. As the (meth) acrylate of an alcohol having an oxygen-containing polar group, for example, a (meth) acrylate of an alcohol having a hydroxyl group and a Z or glycidyl group is used. Examples of the (meth) acrylate of the alcohol having a hydroxyl group include hydroxyethyl (meth) acrylate and hydroxypropyl (methyl) acrylate. Preferably, hydroxyethyl (methyl) acrylate is used. . As the (meth) acrylate of the alcohol having a glycidyl group, for example, glycidyl (meth) acrylate may be mentioned, but glycidyl methacrylate is preferably used. In addition, vinyl monomers having an oxygen-containing polar group such as aryloxyethanol and arylglycidyl ether other than the above (meth) acrylate may also be used as constituent components of the vinyl copolymer having an oxygen-containing polar group. Can be. Examples of the monomer constituting the glassy polymer other than the monomer having an oxygen-containing polar group include alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, and butyl (meth) acrylate, and styrene. And vinyl polymerizable monomers such as aromatic vinyl such as vinyltoluene and α-methylstyrene, vinyl cyanide such as aromatic vinylidene, acrylonitrile and methacrylonitrile, and vinylidene cyanide. Particularly preferred is methyl. Methacrylate, styrene, acrylonitrile and the like are used. The shell phase is preferably in the range of 10 to 50% by weight of the whole core-shell polymer.

An intermediate phase may be present between the first stage and the final polymerization phase. For example, a polymerizable monomer having a functional group such as glycidyl methacrylate, methacrylic acid, hydroxyethyl methacrylate, or the like, a polymerizable monomer that forms a glassy polymer such as methyl methacrylate, or a rubbery polymer such as butyl acrylate An intermediate phase is formed by seed emulsion polymerization of a polymerization monomer or the like that forms a polymer. this Such an intermediate phase can be selected variously depending on the properties of the desired shell shell polymer. The structure of a core-shell polymer having such an intermediate phase is, for example, a multi-layer structure in which another layer exists between the core and the shell, or a structure in which the intermediate layer is finely granular in the core. And those having a dispersed salami structure.

In the present invention, the (C) core-shell polymer is blended in an amount of 1 to 20 parts by weight with respect to (A) 100 parts by weight of the polyacetal resin, and has an effect of improving the friction and wear characteristics by making the surface of the molded article opaque. If the amount is less than 1 part by weight, the effect of reducing the friction coefficient is not sufficiently exhibited, and if the amount is more than 20 parts by weight, the moldability and the frictional characteristics are extremely deteriorated, which is not preferable. Particularly preferably, it is 2 to 10 parts by weight.

In the present invention, in forming a sliding part from the polyacetal resin composition having the above-mentioned components, it is preferable that the polyacetal resin composition has a glossiness of 50% or less, particularly It preferably has a gloss of 30% or less, whereby a particularly excellent sliding effect is produced in the sliding component of the present invention. The glossiness can be adjusted mainly by using the core shell polymer selected as described above and particularly by the amount of addition, and is adjusted in consideration of the blending of the lubricant (B) and optional components. In addition, the glossiness referred to herein means a value measured by a measurement method described later.

The polyacetal resin used in the present invention may further contain various known additives. For example, various colorants, release agents, nucleating agents, antistatic agents, other surfactants, various polymers, and the like. If the performance of the molded article aimed at by the present invention is not significantly reduced, a known filler such as a fibrous, plate-like, or granular filler of inorganic, organic, or metal may be used. It is also possible to mix one or two or more of them. Examples of such fillers include, but are not limited to, glass fiber, glass peas, talc, myriki, osteonite, carbon fiber, and the like. The method for preparing the composition of the present invention is not particularly limited, and it can be easily prepared by known equipment and methods generally used as conventional resin composition preparation methods. For example, i) a method of mixing each component, kneading and extruding with an extruder to prepare pellets, and then molding, and ii) once preparing pellets having a different composition, mixing a predetermined amount of the pellets and molding. Any method can be used, such as a method of obtaining a molded article having a desired composition after molding, a method of directly charging one or more of each component to a molding machine. In addition, it is a preferable method to uniformly mix these components with a small amount of a resin component as a fine powder mixed with other components.

Further, the resin composition according to the present invention can be molded by any of extrusion molding, injection molding, compression molding, vacuum molding, blow molding, and foam molding.

The sliding component of the present invention has a columnar or cylindrical shape, such as a roller, and has a configuration in which a central axis is horizontally supported and rotated, and in particular, an upper portion of the circumferential surface thereof. A particularly remarkable effect occurs when the object moves while sliding. Therefore, it is particularly effective to use a plurality of such sliding parts and arrange them so that their central axes are parallel to form an article transfer device. Brief Description of Drawings

FIG. 1 is a diagram showing a co-molded product used in a practical characteristic test of an example. FIG. 2 is a plan view showing a configuration of a test article transfer device in which a mouth-formed product is arranged. FIG. 3 is a schematic side view showing the state of a practical characteristic test using a test article transfer device. Example

Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited thereto.

In the Examples and Comparative Examples, all “parts” indicate parts by weight. Also, in Examples and Comparative Examples The methods used to evaluate the surface gloss and the coefficient of friction were as follows.

(1) Surface gloss

Using a test piece (70 thigh x 40 thigh x 3 thigh thickness) molded under the following conditions and using a digital gonio-gloss meter (UGV-40, Suga Test Instruments Co., Ltd.) based on the gloss measurement of HS K7105. 45 ° —45 ° in reflection

The gloss was measured.

Molding machine; IS80 manufactured by Toshiba Corporation

(Molding condition)

Nozzle CI C2 C3

Cylinder temperature (° C); 200 200 180 160

Injection pressure: 65MPa

Injection speed; lm / min

Mold temperature; 85 ° C

(2) Friction coefficient

The above test pieces were used and evaluated according to ASTM D-1894. In addition, Zyuracon M90-44 manufactured by Polyplastics Co., Ltd. was used.

(3) Practical characteristics

First, a large number of roller molded products with the shape shown in Fig. 1 (a cylindrical main body with a diameter of 0.5 cm, a length of 5 cm, and a support provided at both ends with a diameter of 0.15 cm and a length of 0.15 cm) were prepared. Individually molded.

Next, prepare two polystyrene plates with a large number of 0.20 cm diameter support holes on the side, and fit the support of the above-mentioned roller molded product into the support holes, Formed the test article transfer device arranged in the state shown in FIG. The positions of the support holes are adjusted so that the upper surface of the placed roller molded product is higher than the upper surface of the polystyrene plate.

Tilt the transfer device to a 3 ° angle as shown in Fig. 3 and The time during which a PET bottle (245 ml: Itoen Oiichi Ocha) slips for a certain distance (30 cm) was measured.

Abbreviations used in Examples and Comparative Examples are as follows.

EA

Methyl methacrylate; View A

Butyl acrylate; BA

Butadiene; BD

2-Ethylhexylacrylate; EHA

2-hydroxyethyl methacrylate; HEMA

Examples 1 to: L3, Comparative Examples 1 to 13

As shown in Table 1, (A) polyacetal resin (manufactured by Polyplastics Co., Ltd., Duracon M270), (B) various lubricants, (C) rubbery polymer core and vinyl copolymer having oxygen-containing polar groups A core shell polymer (P0-0935, core: BAZMMA copolymer, shell; HEMAZMMA, manufactured by Ganz Kasei Co., Ltd.) having a shell of a glassy polymer composed of coalesced is mixed at a ratio shown in Table 1, and then a twin screw extruder is used. The mixture was melt-kneaded in the same manner to prepare a pellet-shaped composition. Next, test pieces were prepared by injection molding using the pellets, and each evaluation was performed. The results are shown in Table 1.

For comparison, as shown in Table 2, a composition not containing the core-shell polymer of the component (C), and a glass-like polymer made of a vinyl copolymer having no oxygen-containing polar group in the shell portion were used. The same evaluation was carried out for a composition containing the used core-shell polymer (P0-0198, manufactured by Ganz Kasei Co., Ltd., core; BDZEHA / MMA terpolymer, shell: MMA / EA copolymer). Table 2 shows the results. table 1

Example

1 2 3 4 5 6 7 8 9

(A) Polycarbonate resin 100 100 100 100 100 100 100 100 100 pairs B-1 B-1 B-1 B-1 B-1 B-2 B-3 B-4 B-5

(B) Lubricating oil

1.0 3.0 5.0 3.0 3.0 1.0 1.0 1.Q 1.0

C-1 C-1 C-1 C-1 C-1 C-1 C-1 C-1 C-1

(0 Coa I Lho. Lima-5.0 5.0 5.0 1.0 10.0 5.0 5.0 5.0 5.0 Sliding coefficient of static friction 0.246 0.103 0.089 0.125 0.115 0.276 0.281 0.245 0.233 Rating Dynamic friction coefficient 0.231 0.098 0.082 0.114 0.107 0.258 0.265 0.236 0.223 Value Gloss (%) 10.1 10.3 9.8 41.3 6.5 9.7 11.3 10.6 10.4 Practical characteristics (sec) 1.83 1.04 0.83 1.32 1.22 2.13 2.24 1.81 1.77

Table 2 Comparative examples

1 2 3 4 5 6 7 8 9

(A) Polyacetal resin 100 100 100 100 100.100 100 100 100 pairs B-1 B-1 B-1 B-2 B-3 B-4 B-5 B-6 B-7

(B) Lubricating oil

1.0 1.0 5.0 1.0 1.0 1.0 1.0 1.0 1.0

(0 Core Shiru I. Lima-Static friction coefficient 0.263 0.131 0.111 0.293 0.303 0.261 0.250 0.331 0.345 Characteristics Dynamic friction coefficient 0.245 0.121 0.104 0.277 0.297 0.255 0.240 0.319 0.328 Value Gloss (%) 72.4 70.6 68.8 71.6 70.3 68.6 66.6 68.3 71.3 Practical characteristics ( Sec) 2.10 1.42 1.20 2.34 2.38 2.05 1.91 2.49 2.63

B-1; Polydimethylsiloxane (60, OOOcSt, manufactured by Toray Industries, Ltd., SH-200)

B-2: Polypropylene glycol (580cSt, PP3000, manufactured by Sanyo Chemical Industries, Ltd.) B-3: Poly (ethylene glycol / propylene glycol copolymer) (1700cSt, 50HB-5100, manufactured by Sanyo Chemical Industries, Ltd.)

B-4: Olefin oligomer (900 cSt, manufactured by Mitsui Petrochemical Industries, Ltd., Lucant body)

B-5: Hyolefin oligomer (28000cSt, Mitsui Petrochemical Co., Ltd., Rouento HC600)

B-6; Paraffin oil (100OcSt, Idemitsu Co., Ltd., process oil)

B-7: Alkyl-substituted diphenyl ether (200cSt, manufactured by Matsumura Petrochemical Laboratory, Moresco High Loop)

B-8: Stearyl stearate

B-9: Distearyl adipate

C-1; Core-shell polymer (Gantz Kasei Co., Ltd., P0-0935, Core: BAZMMA copolymer, Shell: Thigh ZMMA)

C-2: Core-shell polymer (Gantz Kasei Co., Ltd., P0-0198, Core: BDZEHA / MMA Yuichi Polymer 1, Shell: Awake ZEA copolymer)

Claims

The scope of the claims

1. For (A) 100 parts by weight of polyacetal resin, (B) 0.05 to 20 parts by weight of lubricating oil that is in liquid form at 200 ° C, and (C) Rubber-like polymer core and oxygen-containing electrode A sliding component comprising a polyacetal resin composition comprising 1 to 20 parts by weight of a core shell polymer having a glassy polymer shell comprising a vinyl copolymer having a functional group.

2. The sliding component according to claim 1, wherein the polyacetal resin composition has a glossiness of 50% or less.

3. The sliding component according to claim 1, wherein the polyacetal resin composition has a glossiness of 30% or less.

4. The lubricating oil (B) is one or more selected from the group consisting of a silicone oil-based lubricating oil, a fatty acid ester-based lubricating oil and a thioolefin oligomer-based lubricating oil. The sliding component according to any one of claims 3 to 3.

5. The sliding component according to any one of claims 1 to 3, wherein the oxygen-containing polar group of the vinyl copolymer constituting the shell of the core-shell polymer (C) is a hydroxyl group and Z or dalicidyl group.

6. The vinyl-based copolymer having an oxygen-containing polar group constituting the shell of the core-shell polymer (C) is converted into a (meth) acrylate of an alcohol having at least two oxygen-containing polar groups in the molecule as a monomer component. 2. The sliding component according to claim 1, wherein one of the components is copolymerized.

7. The sliding component according to claim 6, wherein the (meth) acrylate of the alcohol having two or more oxygen-containing polar groups in the molecule is hydroxyethyl methacrylate or daricidyl methacrylate.

8. The sliding component according to claim 1, wherein the sliding component has a columnar or cylindrical shape, and rotates with a central shaft supported.

9. An article transfer device comprising a plurality of the sliding parts according to claim 8 arranged so that their central axes are parallel.

10. Use of the polyacetal resin composition according to any one of claims 1 to 3 as a sliding part.