Sliding member for transport device and resin composition

Abstract

The invention provides a sliding member for a transport device and a resin composition, which have excellent wear resistance and can be molded in a special-shaped cross section. The sliding member for a transport device is formed from a resin composition containing (A) a polyacetal resin, and has a wear groove cross-sectional area of 1000 [mu] m2 or less when a pin of JIS K7139 multipurpose test piece A1 type and S45C formed from the resin composition is slid back and forth for 40,000 times under conditions of a movement speed of 6000 mm / min, a load of 500 g, and a one-way movement distance of 20 mm. The polyacetal resin has a melt volume flow rate of 1.0 to 5.0 cm < 3 > / 10 min as measured in accordance with JIS K7210-1.

Description

Technical Field

[0001] The present invention relates to a sliding member for a conveyor device and a resin composition, and more particularly to a sliding member for a conveyor device containing a polyacetal resin as a main component. Background Art

[0002] Polyacetal resin is a plastic with excellent mechanical properties, electrical properties, chemical resistance and other chemical properties, and has been used in a wide range of applications.

[0003] Here, polyacetal resin has excellent wear resistance and is therefore sometimes used as a sliding member for a conveyor device (Patent Document 1, Patent Document 2).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2014-047262

[0007] Patent Document 2: Japanese Patent Application Publication No. 2006-001693 Summary of the invention

[0008] Problems to be solved by the invention

[0009] Although the use of polyacetal resin in sliding components for conveying devices has been studied as described above, it is assumed to be a component of a chain for conveying. That is, there has been no research on the use of polyacetal resin in rails for conveying devices. The reason for this is that the rails for conveying devices have special-shaped cross-sections such as a U-shape (a shape obtained by removing one side from a quadrilateral) and a hollow structure. In other words, when the rails for conveying devices are extruded, they are extruded into special-shaped cross-sections. However, polyacetal resin shrinks during extrusion molding, so it is difficult to adjust the size of the molded product with a special-shaped cross-section. In addition, so far, for rails for conveying devices, MC nylon (registered trademark) and the like have been molded into plates or round bars by extrusion molding, and then cut to form them. However, cutting processing will of course increase the number of operating steps.

[0010] An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a sliding member for a conveyor device which is excellent in wear resistance and can be molded into a special-shaped cross section, and a resin composition capable of providing the sliding member for a conveyor device.

[0011] Solutions to the problem

[0012] Based on the above problems, the present inventors have conducted research and found that the above problems can be solved by the following means.

[0013] <1> A sliding member for a conveying device, the sliding member being formed from a resin composition containing (A) a polyacetal resin,

[0014] Under the conditions of a moving speed of 6000 mm / min, a load of 500 g, and a one-way moving distance of 20 mm, when a pin of JIS K7139 multi-purpose test piece A1 type and S45C formed of the above resin composition is reciprocated for 40,000 times, the cross-sectional area of ​​the wear groove is 1000 μm 2 The melt volume flow rate of the polyacetal resin measured in accordance with JIS K7210-1 is 1.0 to 5.0 cm 3 / 10 points.

[0015] <2> The sliding member for a conveying device according to <1>, wherein

[0016] The sliding member for the conveying device is an extruded product with a special cross-section.

[0017] <3> The sliding member for a conveying device according to <1>, wherein:

[0018] The resin composition comprises, relative to 100 parts by mass of (A) polyacetal resin, 0.3 to 2.5 parts by mass of (B) a fatty acid metal salt containing calcium and / or magnesium, and 0.3 to 2.5 parts by mass of (C) a fatty acid ester, wherein the mass ratio of (B) / (C) is greater than 0.5 and less than 5.

[0019] <4> The sliding member for a conveying device according to <3>, wherein:

[0020] The fatty acid metal salt (B) has an aliphatic group having 10 to 50 carbon atoms.

[0021] <5> The sliding member for a conveying device according to <1>, wherein

[0022] The sliding component for the conveying device is a special-section extrusion-molded product. The resin composition comprises, relative to 100 parts by mass of (A) polyacetal resin: (B) 0.3 to 2.5 parts by mass of a fatty acid metal salt containing calcium and / or magnesium, and (C) 0.3 to 2.5 parts by mass of a fatty acid ester, wherein the mass ratio of (B) / (C) is greater than 0.5 and less than 5, and the fatty acid metal salt (B) has an aliphatic group having 10 to 50 carbon atoms.

[0023] <6> The sliding member for a conveyance device according to <1> or <5>, which is a conveyance rail.

[0024] <7> A resin composition comprising (A) a polyacetal resin, and containing: (B) 0.3 to 2.5 parts by mass of a fatty acid metal salt containing calcium and / or magnesium, and (C) 0.3 to 2.5 parts by mass of a fatty acid ester, relative to 100 parts by mass of the polyacetal resin (A), wherein the mass ratio of (B) / (C) is 0.5 or more and less than 5, and the melt volume flow rate of the polyacetal resin measured in accordance with JIS K7210-1 is 1.0 to 5.0 cm 3 / 10 points.

[0025] <8> The resin composition according to <7>, which is a conveyor rail.

[0026] Effects of the Invention

[0027] According to the present invention, there can be provided a sliding member for a conveyor device which is excellent in wear resistance and can be molded into a special-shaped cross section, and a resin composition which can provide the sliding member for a conveyor device. DETAILED DESCRIPTION

[0028] Hereinafter, a mode for implementing the present invention (hereinafter, simply referred to as "this embodiment") will be described in detail. It should be noted that the following this embodiment is an example for describing the present invention, and the present invention is not limited to this embodiment.

[0029] In addition, in this specification, "to" is used to mean that the numerical values ​​described before and after it are included as a lower limit and an upper limit.

[0030] In this specification, various physical property values ​​and characteristic values ​​are values ​​at 23°C unless otherwise specified.

[0031] The measurement methods and the like described in the standards shown in this specification may differ depending on the year, but unless otherwise specified, they are based on the standards as of January 1, 2022.

[0032] The sliding member for a conveyor device of the present embodiment is formed of a resin composition containing (A) a polyacetal resin, and the cross-sectional area of ​​the wear groove is 1000 μm when a pin of a JIS K7139 multi-purpose test piece A1 type and S45C formed of the above resin composition is reciprocated and slid 40,000 times under the conditions of a moving speed of 6000 mm / min, a load of 500 g, and a one-way moving distance of 20 mm. 2 The melt volume flow rate of the polyacetal resin measured in accordance with JIS K7210-1 is 1.0 to 5.0 cm 3 / 10 minutes. Such a member is a sliding member for a conveyor device that has excellent wear resistance and can be formed into a special-shaped cross section.

[0033] <Physical properties of resin composition>

[0034] In this embodiment, under the conditions of a moving speed of 6000 mm / min, a load of 500 g, and a one-way moving distance of 20 mm, a pin of JIS K7139 multi-purpose test piece A1 type and S45C formed of a resin composition containing a polyacetal resin is reciprocated and slid 40,000 times, and the cross-sectional area of ​​the wear groove is 1000 μm 2 As follows. As a method of reducing the cross-sectional area of ​​the wear groove, for example, one or more of the following methods can be cited: (B) a fatty acid metal salt containing calcium and / or magnesium, and (C) a fatty acid ester are added to the resin composition; and their mixing ratio is precisely adjusted. In particular, this can be achieved by using the following resin composition: the resin composition contains (A) a polyacetal resin, and relative to 100 parts by mass of the (A) polyacetal resin, contains (B) 0.3 to 2.5 parts by mass of a fatty acid metal salt containing calcium and / or magnesium, and (C) 0.3 to 2.5 parts by mass of a fatty acid ester, the mass ratio of (B) / (C) is greater than 0.5 and less than 5, the fatty acid metal salt (B) has an aliphatic group having 10 to 50 carbon atoms, and the melt volume flow rate of the polyacetal resin measured in accordance with JIS K7210-1 is 1.0 to 5.0 cm 3 / 10 points.

[0035] The cross-sectional area of ​​the wear groove is preferably 950 μm 2 Less than, more preferably 900 μm 2 Below, more preferably 850 μm 2 Below, more preferably 800 μm 2 Below, more preferably 750 μm 2 The lower limit of the cross-sectional area of ​​the wear groove is 0 μm. 2 is ideal, in practice 100μm 2 above.

[0036] Next, each component contained in the resin composition used in this embodiment is demonstrated.

[0037] <(A) Polyacetal resin>

[0038] The resin composition contains a polyacetal resin. By containing the polyacetal resin, a sliding member for a conveyor device having excellent slidability and mechanical strength can be obtained.

[0039] The polyacetal resin used in this embodiment has an acetal structure -(-O-CRH-) n- (wherein R represents a hydrogen atom or an organic group) as a repeating structure of the polymer, usually R is a hydrogen atom of the oxymethylene (-CH2O-) as the main constituent unit. The polyacetal resin used in this embodiment, in addition to the acetal homopolymer formed only by the repeating structure, also includes copolymers (including block copolymers), terpolymers, etc. containing one or more constituent units other than the above-mentioned oxymethylene, and in addition, not only has a linear structure, but also can have a branched, cross-linked structure.

[0040] As constituent units other than the above-mentioned oxymethylene groups, for example, optionally branched oxyalkylene groups having 2 to 10 carbon atoms, such as oxyethylene groups (-CH2CH2O-), oxypropylene groups (-CH2CH2CH2O-), and oxybutylene groups (-CH2CH2CH2CH2O-), are mentioned, among which optionally branched oxyalkylene groups having 2 to 4 carbon atoms are preferred, and oxyethylene groups are particularly preferred. In addition, the content of such oxyalkylene constituent units other than the oxymethylene groups is preferably 0.1 mol% to 20 mol%, and more preferably 0.1 mol% to 15 mol% in the polyacetal resin.

[0041] The polyacetal resin used in the present embodiment can be produced by any method known in the art. For example, as a method for producing a polyacetal resin having oxymethylene and oxyalkylene having 2 or more and 4 carbon atoms as constituent units, a method of producing a polyacetal resin having oxymethylene and oxyalkylene having 2 or more and 4 carbon atoms as constituent units can be exemplified by: alkane), tetramer (tetra The present invention can be produced by copolymerizing a cyclic oligomer of an oxymethylene group such as ethylene oxide, 1,3-dioxolane, 1,3,6-trioxocane, and 1,3-dioxepane with a cyclic oligomer of an oxyalkylene group having 2 to 4 carbon atoms.

[0042] Among them, the polyacetal resin used in the present invention is preferably tri- Alkane, tetra The copolymer of cyclic oligomers such as oxirane and ethylene oxide and / or 1,3-dioxolane is particularly preferred. In this case, the total amount of ethylene oxide and / or 1,3-dioxolane is preferably 1 to 20% by mass based on 80 to 99% by mass of the cyclic oligomer.

[0043] The melt volume flow rate (MVR) of the polyacetal resin is 1.0 cm / s when measured under the conditions of JIS K7210-1. 3 / 10 points or more, preferably 1.5cm 3 / 10 minutes or more, more preferably 2.0 cm 3 / 10 minutes or more. In addition, the above MVR is 5.0cm 3 / 10 minutes or less, preferably 4.5cm 3 / 10 minutes or less, more preferably 4.0 cm 3 / 10 minutes or less, more preferably 3.5 cm 3 By adjusting the MVR of the polyacetal resin, there is a tendency that the generation of voids during molding (particularly during extrusion molding) can be effectively suppressed.

[0044] When the resin composition contains two or more polyacetal resins, it is preferred that the MVR of the mixture satisfies the above range.

[0045] The resin composition preferably contains (A) polyacetal resin at a ratio of 80% by mass or more of the resin composition, more preferably at a ratio of 85% by mass or more, further preferably at a ratio of 90% by mass or more, and further preferably at a ratio of 95% by mass or more. The upper limit is the amount of the total amount of polyacetal resin other than (B) fatty acid metal salt and (C) fatty acid ester described later.

[0046] The resin composition may contain only one kind of (A) polyacetal resin or two or more kinds of them. When containing two or more kinds of them, the total amount is preferably within the above range.

[0047] <(B) Fatty acid metal salt containing calcium and / or magnesium>

[0048] The resin composition preferably contains 0.3 to 2.5 parts by mass of (B) a fatty acid metal salt containing calcium and / or magnesium, relative to 100 parts by mass of (A) the polyacetal resin. By containing the fatty acid metal salt (B), slidability can be imparted to the molded article.

[0049] The (B) fatty acid metal salt used in the present embodiment contains a calcium salt and / or a magnesium salt, and preferably contains at least a calcium salt.

[0050] The fatty acid metal salt (B) used in the present embodiment preferably has an aliphatic group having 10 to 50 carbon atoms. The carbon number is preferably 12 or more, more preferably 14 or more, and preferably 36 or less, more preferably 28 or less, further preferably 25 or less, and further preferably 20 or less.

[0051] The aliphatic group is preferably a straight-chain aliphatic group. In addition, the aliphatic group may be a saturated aliphatic group or an unsaturated aliphatic group, but is preferably a saturated aliphatic group.

[0052] More specifically, examples of the fatty acid constituting the fatty acid metal salt include myristic acid, pentadecanoic acid, palmitic acid, heptadecanoic acid, stearic acid, arachidic acid, heneicosanoic acid, behenic acid, lignoceric acid, hexacosanoic acid, and montanic acid, and stearic acid is preferred.

[0053] In the present embodiment, (B) the fatty acid metal salt is preferably calcium stearate or magnesium stearate, and more preferably calcium stearate.

[0054] Relative to 100 parts by mass of polyacetal resin, the content of (B) fatty acid metal salt in the above-mentioned resin composition is preferably more than 0.3 parts by mass, more preferably more than 0.4 parts by mass, further preferably more than 0.6 parts by mass, further preferably more than 0.8 parts by mass, and further preferably more than 0.9 parts by mass. By being set to more than the above-mentioned lower limit, there is a tendency of slippage during molding when used in combination with fatty acid esters that can be effectively suppressed. In addition, relative to 100 parts by mass of polyacetal resin, the content of (B) fatty acid metal salt is preferably less than 2.5 parts by mass, more preferably less than 2.2 parts by mass, further preferably less than 2.0 parts by mass, further preferably less than 1.5 parts by mass, and further preferably less than 1.2 parts by mass. By being set to less than the above-mentioned upper limit, there is a tendency of discoloration when heat is applied to the molded product that can be effectively suppressed.

[0055] The resin composition may contain only one type of (B) fatty acid metal salt or two or more types. When containing two or more types, the total amount is preferably within the above range.

[0056] <(C) Fatty acid ester>

[0057] The resin composition of the present embodiment preferably contains 0.3 to 2.5 parts by mass of the (C) fatty acid ester relative to 100 parts by mass of the (A) polyacetal resin. By containing the (C) fatty acid ester, the slidability of the obtained molded article can be improved.

[0058] (C) fatty acid ester is a compound having one or more ester bonds in the molecule, preferably a fatty acid full ester. Fatty acid ester generally refers to a compound obtained by reacting the COOH of a fatty acid with the OH of an alcohol, and is a compound obtained by esterifying the COOH from a fatty acid with the OH from an alcohol. By using a fatty acid full ester, the limiting PV value for a resin component can be further improved. It should be noted that, for the fatty acid full ester in the present embodiment, when using a commercial product, etc., a compound containing unreacted free COOH from a fatty acid and free OH from an alcohol can sometimes be contained in a part thereof within the range generally allowed by those skilled in the art.

[0059] The number of ester groups in one molecule of the fatty acid ester (C) is preferably 1 to 4, more preferably 1 to 3, further preferably 1 or 2, and further preferably 1.

[0060] The molecular weight of the fatty acid ester (C) is preferably 300 to 2000. In particular, when the fatty acid ester (C) has one ester group, the molecular weight is preferably 300 to 800, when the fatty acid ester (C) has two ester groups, the molecular weight is preferably 300 to 800, when the fatty acid ester (C) has two ester groups, the molecular weight is preferably 300 to 1000, when the fatty acid ester (C) has three ester groups, the molecular weight is preferably 500 to 1200, and when the fatty acid ester (C) has four ester groups, the molecular weight is preferably 800 to 2000.

[0061] In addition, the (C) fatty acid ester used in the present embodiment preferably has an aliphatic group having 10 to 50 carbon atoms, and the above-mentioned carbon number is more preferably 12 or more, and further preferably 14 or more, and is preferably 36 or less, more preferably 28 or less, further preferably 25 or less, and further preferably 20 or less.

[0062] The aliphatic group is preferably a straight-chain aliphatic group. In addition, the aliphatic group may be a saturated aliphatic group or an unsaturated aliphatic group, but is preferably a saturated aliphatic group.

[0063] More specifically, examples of the fatty acid constituting the (C) fatty acid full ester include myristic acid, pentadecanoic acid, palmitic acid, heptadecanoic acid, stearic acid, arachidic acid, heneicosanoic acid, behenic acid, lignoceric acid, hexacosanoic acid, and montanic acid, and stearic acid is preferred.

[0064] As the fatty acid ester (C), stearyl stearate, glycol distearate, pentaerythritol tetrastearate, and stearic acid triglyceride are preferred, stearyl stearate, pentaerythritol tetrastearate, and stearic acid triglyceride are more preferred, and stearyl stearate is further preferred.

[0065] Relative to (A) polyacetal resin 100 mass parts, the content of (C) fatty acid ester in the resin combination of the present embodiment is preferably more than 0.3 mass parts, more preferably more than 0.5 mass parts, more preferably more than 0.8 mass parts, and more preferably more than 0.9 mass parts. By being set to more than the above-mentioned upper limit value, there is a tendency of further shortening the metering time during molding. In addition, relative to (A) polyacetal resin 100 mass parts, the content of above-mentioned (C) fatty acid ester is preferably less than 2.5 mass parts, more preferably less than 2.2 mass parts, more preferably less than 2.0 mass parts, more preferably less than 1.5 mass parts, and more preferably less than 1.2 mass parts. By being set to less than the above-mentioned upper limit value, there is a tendency that the metering stability during molding further improves.

[0066] The resin composition of the present embodiment may contain only one type of (C) fatty acid ester, or may contain two or more types. When containing two or more types, the total amount is preferably within the above range.

[0067] In the resin composition of the present embodiment, the mass ratio of (B) fatty acid metal salt to (C) fatty acid ester (mass ratio of (B) / (C)) is preferably 0.5 or more, more preferably 0.6 or more, further preferably 0.8 or more, and further preferably 0.9 or more. By setting it to above the above lower limit, there is a tendency that the metering time during molding can be further shortened. In addition, the mass ratio of the above (B) / (C) is less than 5, preferably 4 or less, more preferably 3 or less, further preferably less than 3, further preferably 2 or less, further preferably 1.5 or less, and further more preferably 1.2 or less. By setting it to below the above upper limit, there is a tendency that the dynamic friction coefficient for metal components can be further reduced.

[0068] <Other ingredients>

[0069] In the range that does not impair the purpose of the present invention, known additives and fillers can be added to the above-mentioned resin composition. As additives and fillers that can be used in this embodiment, specifically, for example, known thermoplastic polymers, antioxidants, antistatic agents, ultraviolet absorbers, heat stabilizers, light stabilizers, carbon fibers, glass fibers, glass flakes, talc, mica, calcium carbonate, potassium titanate whiskers, etc. can be cited.

[0070] The total content of these components is preferably 10% by mass or less of the resin composition.

[0071] The resin composition preferably contains substantially no other slidability improving agent other than (B) the fatty acid metal salt and (C) the fatty acid ester. Substantially containing no other slidability improving agent means that the content of the other slidability improving agent is 10% by mass or less, preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 1% by mass or less of the total amount of the fatty acid metal salt and (C) the fatty acid ester. Examples of the other slidability improving agent include silicone and fluororesin.

[0072] The MVR of the resin composition used in the present embodiment measured in accordance with JIS K7210-1 is preferably 6.0 cm 3 / 10 minutes or less, more preferably 5.0 cm 3 / 10 minutes or less, more preferably 4.0 cm 3 / 10 minutes or less, more preferably 3.5 cm 3 / 10 minutes or less. In addition, the lower limit of the above MVR is preferably 1.0 cm 3 / 10 points or more, can be 2.0cm 3 / 10 points or more, also 2.5cm 3 / 10 points or more, can also exceed 2.7cm 3 By setting it as such a range, there is a tendency that a sliding member for a conveyor device having a more excellent profile extrusion property can be obtained.

[0073] <Method for producing resin composition>

[0074] The resin composition used in the present embodiment can be easily prepared by a known method generally used as a method for preparing an existing thermoplastic resin composition. For example, the following methods can be used: (1) a method of mixing all the components constituting the resin composition, supplying them to an extruder, and melt-kneading them to obtain a granular composition; (2) a method of supplying a part of the components constituting the composition from the main feed port of the extruder, supplying the remaining components from the side feed port, and melt-kneading them to obtain a granular composition; (3) a method of temporarily preparing pellets of different compositions by extrusion, etc., mixing the pellets, and adjusting them to a given composition, etc.

[0075] Examples of the mixer include a kneader, a Banbury mixer, an extruder, etc. There are no particular restrictions on the various conditions and devices for mixing / kneading, and they can be appropriately selected and determined from any known conditions. Kneading is preferably carried out at a temperature above the melting temperature of the polyacetal resin, specifically above the melting temperature of the polyacetal resin (generally above 180° C.).

[0076] <Sliding member for conveyor device>

[0077] The sliding member for the conveying device of the present embodiment is formed by the above-mentioned resin composition. The sliding member for the conveying device of the present embodiment is preferably manufactured by granulating the above-mentioned resin composition and then performing profiled cross-section extrusion molding. In addition, the sliding member for the conveying device of the present embodiment can also be manufactured by directly performing profiled cross-section extrusion molding on the resin composition after melt kneading using an extruder. That is, the sliding member for the conveying device of the present embodiment is preferably a profiled cross-section extrusion molding. As a method that can perform profiled cross-section extrusion molding, it can be achieved, for example, by the following method: (B) a fatty acid metal salt containing calcium and / or magnesium, (C) a fatty acid ester are added to the polyacetal resin; and their mixing ratio is precisely adjusted.

[0078] The transport sliding member of the present embodiment is preferably a transport rail.

[0079] In addition, the transport sliding member of the present embodiment may be used as a transport sliding member combined with other resin sliding members, fiber-reinforced resin sliding members, and ceramic or metal sliding members. Of course, the sliding members of the present embodiment may be used in combination with each other.

[0080] Example

[0081] Below, give embodiment and the present invention is described more specifically.As long as do not depart from the gist of the present invention, the material, dosage, ratio, processing content, processing steps etc. shown in the following embodiment can be appropriately changed.Therefore, the scope of the present invention is not limited to the specific example shown below.

[0082] When the measuring equipment used in the examples is difficult to obtain due to discontinuation of production or the like, other equipment having equivalent performance may be used for measurement.

[0083] 1. Raw materials

[0084] The raw materials shown in Table 1 were used.

[0085] [Table 1]

[0086]

[0087] The melt volume flow rate (MVR, unit: cm 3 / 10 points).

[0088] 2. Production of resin composition (pellets, POM-1 to POM-17)

[0089] The components shown in Table 2 or Table 3 were uniformly mixed using a roller in the ratio (parts by mass) shown in Table 2 or Table 3. The obtained mixture was melt-shear mixed using a twin-screw extruder (PCM30 manufactured by Ikegai Co., Ltd.) at a barrel temperature of 190° C., a screw speed of 120 rpm, and a discharge rate of 10 kg / h to produce pellets of the resin composition.

[0090] [Table 2]

[0091]

[0092] [Table 3]

[0093]

[0094] The MVR in Tables 2 and 3 above indicates the MVR of the resin composition.

[0095] 3. Examples 1 to 9, Comparative Examples 1 to 10

[0096] <JIS K7139 Multipurpose Test Specimen A1 Molding>

[0097] Using the pellets obtained above (commercially available products were used in Comparative Examples 1 and 2), JIS K7139 multipurpose test piece A1 type (plate) was molded by EC100SX manufactured by Shibaura Machine Co., Ltd. at a cylinder temperature of 195°C, a mold temperature of 90°C, a holding pressure of 80 MPa, and an injection speed of 19.3 mm / s.

[0098] <Wear groove cross-sectional area>

[0099] The wear groove cross-sectional area was measured when the JIS K71 39 multipurpose test piece A1 type (plate) and the S45C pin obtained above were reciprocated 40,000 times under the conditions of a moving speed of 6,000 mm / min, a load of 500 g, and a one-way moving distance of 20 mm using SURFCOM 3000A manufactured by ACCRETECH.

[0100] <Special Shape Extrusion>

[0101] The pellets obtained above (commercial products were used in Comparative Examples 1 and 2) were extruded by FS50 manufactured by Ikegai Co., Ltd. at a barrel temperature of 180° C., a screw speed of 9.0 rpm, and a cooling die temperature of 60° C. The cross section of the extruded pellets was in the shape of a U.

[0102] The case where it is suitable for profile extrusion molding is "suitable", and the case where it is not suitable for profile extrusion molding is "unsuitable". An example of unsuitability for profile extrusion molding is the generation of voids. The judgment is made by 5 experts by majority vote.

[0103] <Cutting>

[0104] The case where profile extrusion molding is possible and cutting processing is not required is marked as “not required”, and the case where profile extrusion molding is not possible and cutting processing is required is marked as “required”.

[0105] [Table 4]

[0106] Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Example 4 Board material POM-1 POM-2 POM-3 UHWPE MC Nylon POM-4 POM-10 <![CDATA[Wear groove cross-sectional area (μm 2 )]]> 740 640 700 2990 7210* 18005 704 Profile Extrusion Suitable Suitable Suitable Not suitable Not suitable Suitable Suitable Cutting unnecessary unnecessary unnecessary need need unnecessary unnecessary

[0107] [Table 5]

[0108] Example 5 Example 6 Example 7 Example 8 Example 9 Comparative Example 4 Board material POM-11 POM-12 POM-13 POM-14 POM-15 POM-5 <![CDATA[Wear groove cross-sectional area (μm 2 )]]> 866 225 750 780 380 3500 Profile Extrusion Suitable Suitable Suitable Suitable Suitable Suitable Cutting unnecessary unnecessary unnecessary unnecessary unnecessary unnecessary

[0109] [Table 6]

[0110] Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 Comparative Example 9 Comparative Example 10 Board material POM-6 POM-7 POM-8 POM-9 POM-16 POM-17 <![CDATA[Wear groove cross-sectional area (μm 2 )]]> 2000 800 87060 12650 255 8900 Profile Extrusion Suitable Not suitable Not suitable Not suitable Not suitable Suitable Cutting unnecessary need need need need unnecessary

[0111] In Comparative Example 2, the wear test was stopped because the upper limit of the friction force was reached during the test.

[0112] It is clear from the above results that in Examples 1 to 9, it is possible to form a molded product by extrusion molding with a special cross section. In particular, for a special extrusion molded product, a suitable special extrusion molded product as a molded product can be obtained without cutting. In addition, the wear resistance is also excellent.

[0113] In contrast, in Comparative Examples 1 and 2 using resins other than polyacetal resin, profile extrusion could not be performed and cutting was required.

[0114] In addition, even when polyacetal resin was used, profile extrusion could not be performed or the wear resistance was poor without adjusting the composition of the resin composition (Comparative Examples 3 to 10). In particular, in Comparative Examples 6 to 8, voids were generated in the molded products and profile extrusion molding could not be properly performed.

Claims

1. A sliding member for a conveying device, which is formed from a resin composition containing (A) a polyacetal resin, When the pins of JIS K7139 multi-purpose test pieces A1 and S45C formed of the resin composition were reciprocated 40,000 times under the conditions of a moving speed of 6,000 mm / min, a load of 500 g, and a one-way moving distance of 20 mm, the cross-sectional area of ​​the wear groove was 1,000 μm. 2 the following, The melt volume flow rate of the polyacetal resin measured according to JIS K7210-1 is 1.0 to 5.0 cm 3 / 10 points.

2. The sliding member for a conveying device according to claim 1, wherein: The sliding member for the conveying device is an extruded product with a special cross-section.

3. The sliding member for a conveying device according to claim 1, wherein: The resin composition comprises, relative to 100 parts by mass of the (A) polyacetal resin: (B) 0.3 to 2.5 parts by mass of a fatty acid metal salt containing calcium and / or magnesium, and (C) 0.3 to 2.5 parts by weight of fatty acid ester, The mass ratio of (B) / (C) is 0.5 or more and less than 5.

4. The sliding member for a conveying device according to claim 3, wherein: The fatty acid metal salt (B) has an aliphatic group having 10 to 50 carbon atoms.

5. The sliding member for a conveying device according to claim 1, wherein: The sliding member for the conveying device is an extruded product with a special cross section. The resin composition comprises, relative to 100 parts by mass of the (A) polyacetal resin: (B) 0.3 to 2.5 parts by mass of a fatty acid metal salt containing calcium and / or magnesium, and (C) 0.3 to 2.5 parts by weight of fatty acid ester, The mass ratio of (B) / (C) is 0.5 or more and less than 5, The fatty acid metal salt (B) has an aliphatic group having 10 to 50 carbon atoms. The sliding member for a conveying device according to claim 1 or 5, which is a conveying rail.

7. A resin composition comprising (A) a polyacetal resin, and comprising, relative to 100 parts by mass of the (A) polyacetal resin: (B) 0.3 to 2.5 parts by mass of a fatty acid metal salt containing calcium and / or magnesium, and (C) 0.3 to 2.5 parts by weight of fatty acid ester, The mass ratio of (B) / (C) is 0.5 or more and less than 5, The melt volume flow rate of the polyacetal resin measured according to JIS K7210-1 is 1.0 to 5.0 cm 3 / 10 points. The resin composition according to claim 7 , which is a conveyor rail.

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