JP2019014891A - A composition for a slide member and the slide member - Google Patents

Abstract

To provide the composition for the sliding member that can maintain a lubricating effect even in an initial stage of sliding and over a long period of time and can provide the sliding member with suppressed abrasion.SOLUTION: The composition for the sliding member comprises: a base material, a first lubricant configured to act at an initial stage of sliding, and a second lubricant configured to act after the initial stage of the sliding and having a viscosity higher than that of the first lubricant, wherein in one embodiment, the composition for the sliding member may have the first lubricant configured to be supported on a carrier and the second lubricant may be a solid lubricant.SELECTED DRAWING: None

Description

  The present invention relates to a sliding member composition and a sliding member.

  Conventionally, for example, a sliding member such as a bearing has been provided with a lubricating function for the purpose of maintaining and improving its slidability.

In Patent Document 1, a fluororesin is used as a base material on both skirt surface surfaces in the diameter direction orthogonal to the piston insertion direction on the outer peripheral cylindrical surface of a piston of an internal combustion engine, and this base material is solid lubricated with MoS ₂ or graphite. It describes that a fluororesin film containing an agent is formed. By forming such a fluororesin film, it is said that it is possible to reduce piston slap noise generated by collision between the piston skirt and the cylinder, for example, by reducing the sliding resistance of the piston. Yes.

  Patent Document 2 describes a bearing cage in which a polyamideimide resin having continuous air holes is impregnated with a fully fluorinated oil such as perfluoropolyether or perfluoropolyalkylether. With such a structure, the polyamide-imide resin has self-lubricating properties, and the fully fluorinated oil impregnated in the continuous air vents gradually exudes, thereby exhibiting long-term lubricity that cannot be obtained by oiling. It is said that.

  Patent Document 3 includes an inner ring, an outer ring, a plurality of rolling elements that are freely rollable between the inner ring and the outer ring, and a cage that holds the rolling element between the inner ring and the outer ring. In the rolling bearing comprising: a rolling bearing in which the cage is made of a material containing a microcapsule containing at least one of oil, grease, and a lubricant additive. With such a configuration, when a load is applied to the cage or wear occurs, the microcapsule is broken, and at least one of the contained oil, grease, and lubricant additive is contained in the cage. It is said that it is supplied to the sliding contact portion with the inner and outer rings, the lubricity of this sliding contact portion is maintained well over a long period of time, and abnormal noise due to self-excited vibration of the cage and heat generation due to friction are suppressed.

JP-A-54-162014 Japanese Patent Laid-Open No. 61-6429 JP 2005-214255 A

  However, when using a solid lubricant as described in Patent Document 1, the lubricity can be maintained after the lubrication effect by the solid lubricant is expressed, but until the lubrication effect at the initial stage of the slide is expressed, Wear and abnormal noise may occur due to low slidability. As described in Patent Document 2, by impregnating a porous body having continuous air holes with a fully fluorinated oil, the fully fluorinated oil exudes even at the initial sliding stage, thereby obtaining a lubricating effect. On the other hand, it is expected that the lubricating effect will be maintained for a long time and wear will be suppressed, but there is a limit. Also, the fluorinated oil bleeds out from the portion that is not the sliding surface, and the equipment including the bearing is unavoidably contaminated. In addition, in injection molding and extrusion molding, kneading is generally performed using a screw. However, in the case of a resin composition impregnated with oil as in Reference 2, the resin slips on the screw due to the oil. A sufficient kneading process cannot be performed. By using a microcapsule as described in Patent Document 3, the microcapsule is broken by a load on the cage in the initial stage of sliding to obtain lubricity, and bleed out can be suppressed. However, there are limits to maintaining long-term lubrication effects and suppressing wear.

  Accordingly, an object of the present invention is to provide a composition for a sliding member that can provide a sliding member that can maintain a lubricating action even in the initial stage of sliding and for a long period of time and that has suppressed wear. .

  As a result of intensive studies, the present inventor has found that the above-described object can be achieved by using two types of lubricants having a predetermined configuration and different viscosities, and incorporating them into a base material. The headline and the present invention were completed. The gist of the present invention is as follows.

  The first of the present invention is a base material, a first lubricant configured to act at the early stage of sliding, and a second lubricant configured to act after the initial stage of sliding and having a higher viscosity than the first lubricant. The present invention relates to a composition for a sliding member containing a lubricant.

  In the embodiment of the present invention, the second lubricant may be a solid lubricant.

  In the embodiment of the present invention, the first lubricant may be configured to be carried on the carrier. In this case, the first lubricant may be configured such that the liquid lubricant is included in the microcapsule, or, for example, a compound that does not have an abrasive action on the counterpart material when used as a sliding member. It may be supported.

  In the embodiment of the present invention, both the first lubricant and the second lubricant are a combination of silicone lubricants, petroleum lubricants, synthetic hydrocarbon lubricants or fluorine lubricants. Alternatively, a combination of a petroleum lubricant and a glycol or ether lubricant may be used.

  In an embodiment of the present invention, the first lubricant contains, as a main component, at least one selected from silicone oil, petroleum oil, fluorine oil, glycol or ether oil, and synthetic hydrocarbon oil. The second lubricant may contain at least one selected from silicone wax, petroleum wax, fluorine wax and synthetic hydrocarbon wax as a main component.

  In the embodiment of the present invention, the base material may include a resin component. In this case, the resin component may be at least one selected from polyamide, polyolefin, polyphenylene sulfide, polyacetal, polyether ether ketone, polyether imide, fluororesin, phenol resin, epoxy resin, and urethane resin.

  2nd of this invention is related with the sliding member containing the molded object of the above-mentioned composition for sliding members.

  3rd of this invention is related with the bearing or gearwheel which consists of the above-mentioned sliding member.

  According to the composition for a sliding member according to the present invention, it is possible to provide a sliding member capable of maintaining a lubricating action even in the initial stage of sliding and for a long period of time. Further, according to the sliding member including the molded body of the composition for sliding member, it is possible to suppress the wear regardless of the surface roughness of the counterpart material, particularly in the region where the adhesive wear occurs. Therefore, for example, it is possible to provide a bearing or gear having good lubricity and suppressing wear even at the initial stage of sliding or for a long period of time.

It is the figure which showed the time-dependent change of the friction coefficient of Example 1 and Comparative Examples 1-3, and is a result in case a counterpart material is SUS440C. It is an enlarged view of the test time initial stage of FIG. It is the figure which showed the time-dependent change of the friction coefficient of Example 1 and Comparative Examples 1-3, and is a result in case a counterpart material is S45C. FIG. 4 is an enlarged view of an initial test time in FIG. 3. It is the figure which showed the time-dependent change of the friction coefficient of Example 2. It is an enlarged view of the test time initial stage of FIG. It is the figure which showed the time-dependent change of the friction coefficient of the comparisons 4 and 5. FIG. It is an enlarged view of the test time initial stage of FIG. It is the figure which showed the time-dependent change of the friction coefficient of the comparison reference 6. It is the figure which showed the time-dependent change of the friction coefficient of the comparison reference 7. FIG. 6 is a diagram showing a change with time of a friction coefficient of Comparative Example 8. It is the figure which showed the time-dependent change of the friction coefficient of the comparison reference 9. It is the figure which showed the time-dependent change of the friction coefficient of the comparison reference 10. It is the figure which showed the time-dependent change of the friction coefficient of Example 3. It is the figure which showed the time-dependent change of the friction coefficient of Example 4 and Comparative Controls 11 and 12. FIG. 16 is an enlarged view of the initial test time of FIG. 15.

  The composition for sliding members which concerns on embodiment of this invention contains a base material, a 1st lubricant, and a 2nd lubricant. The first lubricant is configured to act at the initial stage of sliding. The second lubricant is configured to act after the initial sliding and has a higher viscosity than the first lubricant.

  Since the first lubricant in the embodiment of the present invention has a relatively lower viscosity than the second lubricant, it can spread quickly over the entire sliding surface. That is, during the period from the start of sliding until the transfer film is formed, the surface lubricant on the sliding surface is quickly covered with the first lubricant to form the lubricating film. On the other hand, after the lubricant film is formed, the second lubricant covers the first lubricant. And since the second lubricant has a higher viscosity than the first lubricant, no excessive bleed-out of the second lubricant occurs on the non-sliding surface, and a relatively low viscosity like the first lubricant. It is possible to maintain the lubricating action for a longer period than in the case of the lubricant alone.

  The first lubricant is configured to act at the initial stage of sliding. As such a configuration, for example, when an external force is applied, when the pressure exceeds a predetermined pressure, when the temperature exceeds a predetermined temperature, etc., the first lubricant is triggered by an action from the external environment. Is configured to flow out to the sliding surface. More specifically, the first lubricant can be configured to be supported on the carrier. The carrier can be configured to collapse due to the action from the external environment as described above and the first lubricant flows out. Examples of the structure of such a carrier include microcapsules and porous fine particles.

  The porous fine particles may be either inorganic fine particles or organic fine particles. As inorganic substances, carbonates such as calcium carbonate and barium carbonate; silicates such as calcium silicate, barium silicate and magnesium silicate; phosphorus such as calcium phosphate, barium phosphate, magnesium phosphate, zirconium phosphate and apatite Examples include acid salts; metal oxides such as silicon dioxide (silica) and alumina; graphite; zeolites; As the layered clay mineral, a layered silicate mineral is preferable. Smectites such as wright, vermiculites, phlogopite, biotite, muscovite, and other mica, brittle mica, and chlorite. Examples of the organic substance include polyethylene, polyurethane, cellulose, polyamide, polyvinyl formal, phenol resin, epoxy resin, urea resin, and the like. However, for example, when a sliding member is used, it is necessary that the member does not have an abrasive action on the counterpart material.

  Examples of the method of supporting the first lubricant on the porous fine particles include a method of impregnating the porous lubricant with the first lubricant. Examples of the impregnation method include a method in which the porous fine particles are immersed in the first lubricant and subjected to heat treatment, reduced pressure treatment, or both.

  The microcapsule is a film formed of, for example, a resin-containing composition, and a first lubricant is included therein. In general, the sliding member, particularly in adhesive wear, has a surface protrusion on the relative surface as the contact area of the sliding surface increases from the beginning of sliding until the transfer film is formed on the surface of the counterpart material. The coefficient of friction increases due to the effect of. On the other hand, in the embodiment using the microcapsule in the present invention, the microcapsule is ruptured by the surface protrusion from the start of sliding, and the first lubricant contained therein spreads quickly over the entire sliding surface. After the good lubricating film is formed, friction between the adhesion films occurs, so that no excessive bleed-out of the first lubricant occurs on other than the sliding surface. As a result, in the embodiment of the present invention, the sliding characteristics with a low friction coefficient are stably exhibited from the start of sliding to the formation of the transfer film without causing bleed out.

  The structure of the microcapsule is not particularly limited, and may be a single layer film or a multilayer film. From the viewpoint of suppressing the generation of pinholes, a multilayer film is preferable.

  Examples of the resin contained in the microcapsule include polyurethane resin, polyester resin, polyamide resin, polyurea resin, phenol resin, polyvinyl alcohol resin, melamine resin, polyethylene resin, polystyrene resin, cellulose, Examples include gelatin. These may be contained alone or in combination of two or more.

  Microcapsules can be obtained by employing a conventionally known method. For example, a method of depositing a substance to be coated on the surface of the substance to be encapsulated (interface deposition method), or a method of forming a film using a reaction on the surface of the substance to be encapsulated (interface reaction method) can be employed. Examples of the interface deposition method include a phase separation method, a submerged drying method, a melt dispersion cooling method, a spray drying method, a pan coating method, an air suspension coating method, and a powder bed method. Examples of the interfacial reaction method include an interfacial polymerization method, an in situ polymerization method, a submerged cured film method, and the like. These methods can be appropriately selected in consideration of the first lubricant, the material constituting the microcapsules, and the like.

  Among the above-mentioned carriers, from the viewpoint of imparting good lubricity at the initial stage of sliding, microcapsules, graphite-made porous fine particles and layered clay mineral-made porous fine particles are preferable, and microcapsules and graphite-made fine particles are preferable. Porous fine particles are more preferable.

  The average particle diameter of the microcapsules and the porous fine particles is not particularly limited, but is preferably 15 μm or more from the viewpoint that the microcapsules and the porous fine particles burst and the first lubricant is supplied to the sliding surface as needed. Moreover, 100 micrometers or less are preferable from a viewpoint which suppresses the damage at the time of manufacturing the composition for sliding members, and the viewpoint which ensures the content of the microcapsule and porous microparticles | fine-particles in the composition for sliding members more than fixed. Therefore, the average particle diameter of the microcapsules and the porous fine particles is preferably 15 to 100 μm. More preferably, it is 20-90 micrometers, More preferably, it is 30-80 micrometers. The average particle diameter can be measured by a measuring method such as a laser diffraction disturbance method or a sieving method.

  The content of the first lubricant with respect to the microcapsules and the porous fine particles is 40 to 80% by mass from the viewpoint of imparting good lubricity and the strength of the microcapsule film and the amount of adsorbed and retained on the porous fine particles. preferable.

  The content of the microcapsule containing the first lubricant and the composition of the porous fine particles in the sliding member composition is 2 to 10 mass from the viewpoint of imparting good lubricity and ensuring the strength of the sliding member. % Is preferable, and 2 to 7% by mass is more preferable.

The first lubricant has a lower viscosity than the second lubricant. From the viewpoint of facilitating spreading on the sliding surface in the early stage of sliding of the sliding member, a lubricant having good fluidity is preferable, and liquid lubricant is more preferable. For example, it preferably has the following 1500 mm ² / s kinematic viscosity at 40 ° C., and more preferably the following 1000 mm ² / s, more preferably those following 500 mm ² / s, particularly preferably not less 100 mm ² / s The most preferable is 50 mm ² / s or less. Liquid lubricant is also referred to as oil.

  Examples of the first lubricant include silicone lubricants, petroleum lubricants, fluorine lubricants, glycol or ether lubricants, and synthetic hydrocarbon lubricants. These may contain 1 type, or 2 or more types.

  As the silicone lubricant, silicone oil is preferable. Examples of the silicone oil include dimethyl silicone oil, methylphenyl silicone oil, methyl hydrogen silicone oil, and modified silicone oil obtained by modifying a part of the methyl group of dimethyl silicone oil.

  As the petroleum lubricant, petroleum oil is preferable. Examples of petroleum oils include aromatic hydrocarbons, paraffin hydrocarbons (also referred to as paraffin oil), and naphthene hydrocarbons.

  As the fluorine-based lubricant, fluorine-based oil is preferable. Examples of the fluorinated oil include fluoroethylene, trifluorinated ethylene chloride, perfluoropolyether, perfluoropolyalkyl ether, and the like.

  As the glycol-based or ether-based lubricant, glycol-based or ether-based oils are preferable. Examples of the glycol-based or ether-based oil include aromatic glycol-based or ether-based oils, aliphatic glycol-based or ether-based oils, and the like. Examples of the aromatic glycol-based or ether-based oil include alkyl diphenyl ether, monoalkyl triphenyl ether, dialkyl diphenyl ether, tetraphenyl ether, pentaphenyl ether, monoalkyl tetraphenyl ether, dialkyl tetraphenyl ether, and the like. Examples of the aliphatic glycol-based or ether-based oil include polyalkylene glycols such as polyethylene glycol and polypropylene glycol; polyethylene glycol monoalkyl ether, polypropylene glycol monoalkyl ether; and the like.

  As the synthetic hydrocarbon lubricant, a synthetic hydrocarbon oil is preferable. Examples of the synthetic hydrocarbon oil include normal paraffin, isoparaffin, polybutene, polyisobutylene, poly α-olefin or a hydride thereof, alkylbenzene, and alkylnaphthalene.

  Among the oils as described above, the first lubricant contains as a main component at least one selected from silicone oil, petroleum oil, fluorine oil, glycol or ether oil, and synthetic hydrocarbon oil. Those that do are preferred. The “main component” means containing 50% by mass or more in the entire first lubricant.

  The second lubricant is configured to act after the initial sliding and has a higher viscosity than the first lubricant. From the viewpoint of imparting a lubricating action for a longer period after the initial sliding, the viscosity of the second lubricant is preferably a melting point of 40 ° C. or higher or one that softens at 40 ° C. or higher. Here, the viscosity of the second lubricant is higher than that of the first lubricant. The first lubricant is a liquid lubricant such as petroleum oil, and the second lubricant is a solid lubricant such as petroleum wax. Means an agent.

  The size of the second lubricant in the base material is preferably 5 μm or more and 300 μm or less, more preferably 10 μm or more and 200 μm or less, more preferably 15 μm from the viewpoint of exhibiting good sliding characteristics. More preferably, it is 100 μm or less. In the case of such a size, the sliding characteristics tend to be exhibited well, and the toughness and surface hardness of the sliding member tend to be maintained well.

  The method for adjusting the size of the second lubricant is not particularly limited, but from the viewpoint of simplicity, for example, a method of forcibly mixing and dispersing using various mixing machines, and the type and basis of the second lubricant to be added. Examples thereof include a method of adding an appropriate dispersant according to the type of material, and a method of adding a substance that increases the melt viscosity of the base material when the second lubricant is added.

  From the viewpoint of imparting a lubricating effect for a longer period after the initial sliding, the second lubricant is preferably a solid lubricant. “Solid” means solid at normal temperature to the operating temperature of the sliding member.

  When the second lubricant is semi-solid like grease or paste, it may be mixed with a solidifying agent for making it solid. Examples of such a solidifying agent include metal soap, metal composite soap, urea compound, silica gel, bentonite, urethane compound, urea / urethane compound, sodium terephthalate compound, phthalocyanine, fluororesin and the like.

  Examples of the second lubricant include silicone lubricants, petroleum lubricants, fluorine lubricants, and synthetic hydrocarbon lubricants. These may contain 1 type, or 2 or more types.

  As the silicone lubricant, a silicone wax is preferable. Examples of the silicone wax include a graft copolymer composed of an acrylic polymer and dimethylpolysiloxane.

  As the petroleum lubricant, a petroleum wax is preferable. Examples of petroleum-based waxes include paraffin wax, microcrystalline wax and petrolatum as defined in JIS K 2235, and processed / modified waxes thereof. Of these, paraffin wax, microcrystalline wax, and processed / modified wax are preferred. Since petrolatum is semi-solid, it is preferable to use a solidifying agent as described above. As the paraffin wax and microcrystalline wax, those having a suitable melting point can be adopted depending on the application. The processed / modified wax is a wax obtained by modifying petroleum-based wax by chemical treatment or blending a synthetic resin having good compatibility with the wax. Examples of such a processed / modified wax include an oxidized wax such as an alcohol type wax and a maleated wax, and a blended wax. Examples of the oxidized wax include alcohol type waxes such as NPS-9210 and 9215 manufactured by Nippon Seiwa Co., Ltd., alcohol type oxide waxes such as OX-1949 and 020T, and maleated waxes such as MAW-9088.

  As the fluorine-based lubricant, fluorine-based wax is preferable. Examples of the fluorine-based wax include polyethylene / PTFE wax and PTFE-modified polyethylene wax.

  As the synthetic hydrocarbon-based lubricant, a synthetic hydrocarbon-based wax and a processed / modified wax thereof are preferable. Examples of the synthetic hydrocarbon wax include Fischer-Tropsch wax, polyethylene wax, and polypropylene wax. The synthetic hydrocarbon wax processed / modified wax is a wax obtained by modifying a synthetic hydrocarbon wax by chemical treatment or blending a synthetic resin having good compatibility with the wax. Examples of such processed / modified wax include oxidized wax, compounded wax and the like. Examples of the oxidized wax include High Wax (registered trademark) -4052E manufactured by Mitsui Chemicals.

  Among the above waxes, the second lubricant preferably contains at least one selected from silicone wax, petroleum wax, fluorine wax, and synthetic hydrocarbon wax as a main component. The “main component” means containing 50% by mass or more in the entire second lubricant.

  The content of the second lubricant in the sliding member composition is preferably 3 to 25% by mass, and 5 to 20% by mass from the viewpoint of imparting good lubricity and ensuring the strength of the sliding member. Is more preferable.

  The first lubricant and the second lubricant can be arbitrarily selected, but from the viewpoint of more effectively demonstrating the effects of the present invention, those that do not greatly differ from each other in molecular structure and polarity are selected. can do. For example, both the first lubricant and the second lubricant are a combination of silicone lubricants, petroleum lubricants, fluorine lubricants and synthetic hydrocarbon lubricants, or petroleum lubricants. And a combination of a glycol-based or ether-based lubricant. When the first lubricant and the second lubricant are in such a specific combination, it is considered that both tend to exist on the sliding surface at the same time. It is thought that it becomes easy to make it. In addition, when a sliding member composition containing such a specific combination of lubricants is used as a sliding member, frictional wear is caused regardless of the surface roughness of the counterpart material, particularly in a region where adhesive wear occurs. It can be suppressed even lower. The silicone lubricant, petroleum lubricant, fluorine lubricant, glycol or ether lubricant and synthetic hydrocarbon lubricant in the first and second lubricants are as described above.

  As such combinations, for example, the following can be mentioned as preferred examples. (A) The first lubricant is a liquid lubricant whose main component is silicone oil, and the second lubricant is a solid lubricant whose main component is a silicone wax. (B) The first lubricant is A liquid lubricant mainly composed of petroleum-based oil, wherein the second lubricant is a solid lubricant mainly composed of petroleum-based wax, and (c) the first lubricant is a liquid mainly composed of fluorine-based oil. (D) the first lubricant is a liquid lubricant whose main component is a synthetic hydrocarbon oil, and the second lubricant is a lubricant, the second lubricant is a solid lubricant whose main component is a fluorine-based wax. (E) The first lubricant is a liquid lubricant mainly composed of glycol-based or ether-based oil, and the second lubricant is petroleum-based. It is a solid lubricant mainly composed of wax. In addition, one type of various lubricants may be used, or two or more types of the same system may be combined. For example, if it is a silicone type, one type of silicone type may be sufficient and two or more types may be sufficient.

  As a base material, the material which can be used in the use of a sliding member is employable. Examples of the material include a resin component.

  As a resin component, what can be used as a sliding member is employable. Examples of such a resin component include thermoplastic resins, thermosetting resins, and the like. More specifically, for example, polyamide, polyolefin, polyphenylene sulfide, polyacetal, polyether ether ketone, polyether imide, and fluorine resin, A phenol resin, an epoxy resin, a urethane resin, etc. are mentioned. 1 type of these resin components may be contained and 2 or more types may be contained. In addition, when the resin is a thermosetting resin, the resin component can include a resin component before the reaction.

  Examples of polyamides include aliphatic polyamides and polyamides containing aromatic rings. Examples of the aliphatic polyamide include nylon (polyamide) 6, 11, 12, 46, 66, 610, 612 and the like. Examples of the polyamide containing aromatics include polyamide MDX-6. The polyamide (nylon) obtained by ring-opening polymerization of lactams may be obtained by a water polymerization method or may be obtained by an anionic polymerization method. The latter is known as so-called monomer casting nylon, and is known as polyamide (nylon) for sliding members.

  Examples of the polyolefin include polyethylene (PE) and polypropylene (PP). The polyethylene may be any of ultra high molecular PE (UHMWPE), high density PE (HDPE), and low density PE (LDPE), or may be linear low density PE (LLDPE).

  The polyphenylene sulfide (PPS) may be a linear type or a crosslinked type.

  The polyacetal (also referred to as POM or polyoxymethylene) may be a homopolymer type or a copolymer type.

  Examples of the fluororesin include polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-ethylene copolymer (ETFE), and tetrafluoroethylene-hexafluoropropylene copolymer. Examples thereof include a polymer (FEP) and polyvinylidene fluoride (PVDF), polyvinylidene fluoride (PVF), polychlorotrifluoroethylene (PCTFE), and vinylidene fluoride-hexafluoropropylene copolymer. These may be used alone or in combination of two or more.

  As a phenol resin, what is necessary is just a reaction material of phenols and aldehydes, and a well-known thing is employable. The phenols are not particularly limited, and examples thereof include alkylphenols (cresol, xylenol, etc.), polyhydric phenols (resorcinol, etc.), phenylphenol, aminophenol, and the like. Moreover, aldehydes are not specifically limited, Formaldehyde, paraformaldehyde, acetaldehyde, a furfural, etc. are mentioned. The phenol resin may be either a resol type or a novolac type. A modified phenolic resin may be used. These can be appropriately selected according to the use of the sliding member. As will be described later, when preparing a prepreg containing a resol type or novolak type phenol resin or the like, a novolak type phenol resin is preferable from the viewpoint of better integration with the dough.

  The resol type phenol resin is, for example, a product obtained by reacting phenols and aldehydes in an excess of aldehydes and in the presence of a base catalyst. The novolak type phenol resin is obtained by, for example, reacting phenols and aldehydes in an excess of phenols and under an acid catalyst. Commercially available resol type phenol resins and novolac type phenol resins can be used. For example, Sumilite Resin (registered trademark) PR series manufactured by Sumitomo Bakelite Co., Ltd. may be mentioned.

  It can be set as a sliding member by hardening a resol type phenol resin and a novolak type phenol resin. The resol type phenolic resin can be cured by heating or acid addition. The novolak type phenol resin can be cured by heating in the presence of a crosslinking agent. Examples of the crosslinking agent for curing the novolak type phenol resin include hexamethylenetetramine. Moreover, the conditions at the time of hardening can be suitably selected according to the kind etc. of a resole type phenol resin and a novolak type phenol resin.

  Examples of the epoxy resin include bisphenol A type, bisphenol F type, novolac type, cyclic aliphatic type, long chain aliphatic type, glycidyl ester type, glycidyl amine type, and the like.

  The urethane resin is a reaction product of an isocyanate and a compound having active hydrogen. Depending on the application, the type of the compound having an isocyanate and active hydrogen can be selected to obtain desired characteristics as a sliding member application. It is possible to employ one having Examples of isocyanates include diisocyanates such as tolylene diisocyanate, diphenylmethane-4,4'-diisocyanate, 1,5-naphthalene diisocyanate, adducts of diisocyanates and polyhydric alcohols, and isocyanate multimers. Examples of the compound having active hydrogen include polyhydroxy compounds (polyols) and polyamines.

  The content of the substrate is preferably 48 to 93% by mass in the sliding member composition.

  You may add another additive to the composition for sliding members. Examples of such additives include heat-resistant agents, reinforcing agents, flame retardants, impact-resistant agents, colorants, crystal nucleating agents, and the like. In particular, when a crystal nucleating agent is contained, a decrease in surface hardness due to the first lubricant and the second lubricant can be suppressed. In the case of containing a reinforcing agent, it is possible to improve mechanical properties and wear resistance when used as a sliding member. Examples of such a reinforcing agent include cloth knitted with short fibers, long fibers, and continuous fibers, canvas, and the like. The type of fiber may be either artificial fiber or natural fiber. Examples of artificial fibers include synthetic fibers such as aramid fibers, polyvinyl alcohol fibers, nylon fibers, and fluororesin fibers; inorganic fibers such as glass fibers and carbon fibers; Examples of natural fibers include cellulose (plant) fibers such as cotton, hemp and flax.

  The composition for a sliding member is obtained by, for example, mixing an additive including a first lubricant having a predetermined configuration, a second lubricant having a predetermined configuration, a base material, and an optional reinforcing agent to be added as necessary. Can be obtained. When the base material is a thermoplastic resin, for example, the above-described materials can be kneaded using a melt kneader. Moreover, before supplying to a melt-kneader, the above-mentioned materials can be mixed with a mixer such as a Henschel mixer. Examples of the melt kneader include a single screw extrusion kneader, a twin screw extrusion kneader, a roll, a kneader, and a Brabender plastograph. When the first lubricant is supported on the carrier, particularly when it is contained in the microcapsule or impregnated in the porous microparticles, it is performed under conditions that prevent damage to the microcapsules and the porous microparticles. Keep in mind. Thus, the composition for sliding members obtained by kneading | mixing can be applied to extrusion molding, injection molding, compression molding, rotational molding etc., and a molded object can be obtained.

  When the substrate is a thermosetting resin, for example, a reactive component such as a monomer or prepolymer, an initiator or a crosslinking agent, a first lubricant having a predetermined configuration, a second lubricant having a predetermined configuration, and as required The composition for a sliding member can be obtained by mixing the additives to be added or by mixing these components and reacting the reactive components. In addition, the varnish which melt | dissolved the prepolymer etc. in the solvent is also contained in the composition for sliding members. Also, after impregnating the varnish into the dough, it is dried to obtain a prepreg, and this is laminated and heated and pressed to obtain a molded body composed of a laminate of the sliding member composition and the dough. it can. Such a laminate is suitable when the resin component is, for example, a phenol resin. Moreover, when forming a laminated body, as a cloth | dough which a varnish is immersed, a well-known thing can be used, For example, a cotton fabric, the textile fabric of various synthetic fibers, a knitted fabric, a nonwoven fabric etc. are mentioned. In order to improve the adhesion between the dough and the substrate, known surface treatments such as silane coupling treatment, titanium coupling treatment, and plasma coating treatment may be performed before the varnish is immersed in the dough.

  The obtained molded body can be suitably used as a sliding member. In addition, a sliding member having a desired shape can be obtained by performing machining such as cutting on the obtained molded body.

  When the resin component is produced by the monomer casting (MC) method, the monomer component or prepolymer component (monomer component, etc.) of the resin component, the first lubricant having a predetermined configuration, the second lubricant having a predetermined configuration, Arbitrary additives to be added as needed, catalysts and co-catalysts necessary for the polymerization reaction of monomers, monomer components, additives and environmental humidity in the atmosphere, and depolymerization and deformation after polymerization The composition for sliding members which contains a resin component as a base material is obtained by adding in the range quantity and conditions which do not affect etc. In this method, a molded product having a desired shape can be obtained by polymerizing the monomer in a desired casting mold. And the molded object can be used as a sliding member. Moreover, a sliding member can also be obtained by performing machining such as cutting on the obtained molded body. In addition, the composition for sliding members obtained by the monomer casting method is a molded body.

  An example in which a composition for a sliding member is obtained by producing polyamide (nylon) 6 as a resin component by the MC method will be described below. In the following, the polyamide 6 produced by the MC method may be referred to as MC polyamide 6.

  The monomer ε-caprolactam, alkali metal catalyst, cocatalyst, first and second lubricants of a predetermined constitution and optional additives are mixed at a temperature equal to or higher than the melting point of ε-caprolactam, and this mixture is 160 to 180 ° C. When it is poured into the mold within the temperature range, it is cured in about several minutes, and a composition for a sliding member (molded article) is obtained.

  Examples of the alkali metal catalyst include ε-caprolactam Na salt, ε-caprolactam K salt, ε-caprolactam Li salt, ε-caprolactam MgBr salt, and ε-caprolactam MgCl salt. Examples of the cocatalyst include acyl lactam, acid chloride, isocyanate, carbonate, ester and urea. Examples of the isocyanate include hexamethylene diisocyanate.

  From the viewpoint of uniformly dispersing the first and second lubricants having a predetermined configuration in the mixture, a compound having a polar group and a nonpolar group may be added. Examples of such a compound include a dispersant. Examples of the dispersant include a cationic surfactant type dispersant, an anionic surfactant type dispersant, an amphoteric surfactant type dispersant, and a polymer type dispersant. However, as a matter of course, those that do not affect the polymerization reaction are used. Such a compound may be added at the stage of producing the sliding member composition, or may be added directly to the microcapsules or the porous fine particles, or both. Moreover, not only manufacture of MC polyamide 6 but it can use.

  Since the polymerization of ε-caprolactam is anionic polymerization, in order to obtain a stable polymer, it is important to control the amount of water contained in the substance that inhibits the reaction, particularly in the system. For example, since water deactivates the activity of the alkali metal catalyst, it is conceivable that the alkali metal catalyst is added excessively in anticipation of this deactivation. However, if it is added excessively, the molecular weight of the polyamide 6 after polymerization becomes low, and the polymer may be deformed when heat treatment is performed for the purpose of relaxing internal stress or improving crystallinity. . Therefore, in consideration of the influence of moisture, the monomer is basically 98.65% by mass of ε-caprolactam as a monomer, 1.10% by mass of ε-caprolactam Na salt as a catalyst, and 0.25% by mass of hexamethylene diisocyanate as a promoter. It is preferable to carry out the polymerization in a range of up to 5 times the basic blending ratio for both the ε-caprolactam Na salt and hexadiisocyanate as the blending ratio (the sum of these three is 100 mass%). That is, ε-caprolactam is 91.90 to 98.65% by mass, ε-caprolactam Na salt is 1.10 to 5.50% by mass, hexamethylene diisocyanate is 0.25 to 1.25% by mass, The total of the three is preferably 100% by mass.

  There is no particular limitation on how to add ε-caprolactam, ε-caprolactam Na salt, and hexamethylene diisocyanate, and (i) a predetermined amount of each of these three components of the polymerization system may be added individually, or (ii) ε-caprolactam Na salt and hexamethylene diisocyanate may be dissolved in ε-caprolactam at a high concentration, respectively, and the addition amount of ε-caprolactam may be adjusted to a predetermined addition amount, or (iii) a mixture Ε-caprolactam Na salt and ε-caprolactam solution adjusted to a desired concentration when mixed, and hexamethylene diisocyanate and ε-caprolactam solution adjusted to a desired concentration when mixed. May be. In addition, there is no particular limitation on how to add the first and second lubricants and optional additives having a predetermined configuration at this time, and a predetermined amount may be added individually, or the above (ii) and ( In the case of iii), a desired concentration may be obtained when a desired amount is added to any of the ε-caprolactam solutions to form a mixture.

  The temperature condition for the polymerization reaction can be appropriately selected within the above-described temperature range depending on the size of the molded article of the sliding member composition generated as a result of the polymerization reaction. The heating time can be appropriately selected according to the size of the molded body and the temperature conditions. For example, in the case of a cylindrical shape having a diameter of 50 mm, it is preferable to react at 160 ° C. to 180 ° C. for 2 hours after heating to 140 ° C. After completion of the reaction, it is cooled to room temperature. Moreover, it is preferable to heat-process after completion | finish of reaction from a viewpoint of internal stress relaxation, a viewpoint of the improvement of a crystallinity degree, etc.

  MC polyamide 6 is known to have excellent wear resistance, a low coefficient of friction, and excellent PV value characteristics. Therefore, the composition for a sliding member containing MC polyamide 6 and the first and second lubricants having the above-described predetermined configuration has characteristics as a sliding member that are even better than MC polyamide 6.

  The molded body or the sliding member of the sliding member composition preferably has a surface hardness of 75 to 85 in Shore D from the viewpoint of suitably functioning as a sliding member. The surface hardness can be measured according to JIS K 7215.

  The molded body of the composition for sliding member obtained as described above can be suitably used as a sliding member. Examples of the sliding member include a bearing, a gear, a piston ring, a seal member, and a chip seal for an air conditioner. Of these, bearings and gears are suitable because the pressure applied to the sliding surface at the initial stage of sliding is high. Of these, the bearings and gears are sliding members that increase the contact area and the friction coefficient on the sliding surface at the initial stage of sliding, so that the effects of the present invention are remarkable.

  Hereinafter, based on an Example, embodiment of this invention is described more concretely.

(Production Example 1): Production of microcapsules including the first lubricant After dissolving 3.5 g of polyethylene maleic anhydride (manufactured by SIGMA-ALDRICH JAPAN) in 50 g of distilled water, a 10% by mass aqueous sodium hydroxide solution was added. The pH was adjusted to about 4 using 065 g. To this aqueous phase was added 34.9 g of an organic phase petroleum oil (manufactured by MORESCO, product name Moresco Food Machine Lub FPL-32, kinematic viscosity: 29.9 mm ² / s), and a homogenizer (manufactured by POLYTRON, PT3100). ) Was stirred at 5000 rpm for 10 minutes to prepare an O / W emulsion. The prepared O / W emulsion was transferred to a jacketed separable flask. To this O / W emulsion was added an additional phase in which 5.66 g of melamine, 10.93 g of 37 wt% aqueous formaldehyde solution, 6.75 g of distilled water and 1.065 g of 10 mass% aqueous sodium hydroxide solution were added (pH about 12), and further 10 The pH of the entire reaction system was adjusted to about 4 by adding 24.98 g of a mass% citric acid aqueous solution. Then, the interfacial polymerization reaction was advanced by stirring at 300 rpm (manufactured by EYERA, NZ-1000) for 3 hours using a Teflon four-blade stirring blade at 80 ° C. to prepare microcapsules. The suspension containing the microcapsules was placed in a centrifuge tube and centrifuged at 8000 rpm for 15 minutes using a centrifuge (MX-307, manufactured by TOMY). After removing the supernatant, distilled water was poured into the centrifuge tube, and the microcapsules were washed by performing the same centrifugal separation operation 10 times as described above. The collected microcapsules were dried under low pressure in a vacuum desiccator for 48 hours. The average particle diameter of the obtained microcapsules was φ50 μm as measured with a product name Laser Microscope VK-8700 manufactured by Keyence Corporation. The content of the first lubricant with respect to the microcapsules was 80% by mass.

Production Example 2 Production of First Lubricant-Containing Graphite After drying graphite (CPB-3, manufactured by Chuetsu Graphite Industries Co., Ltd.) at 100 ° C. for 2 hours, an excess of petroleum oil (produced by MORESCO, product) No. Moresco Food Machine Lube FPL-32) was added and further heated at 100 ° C. for 2 hours. Then, after cooling to normal temperature, it filtered and dried and obtained the graphite which carry | supported petroleum oil. The amount of petroleum oil supported was 25% by mass with respect to graphite.

(Example 1): 4.6% by mass of microcapsules, 9.7% by mass of second lubricant
ε-Caprolactam Na salt (manufactured by Biosynth): 6.27 g and ε-caprolactam (manufactured by Wako Pure Chemical Industries, Ltd.): 46.79 g were taken in a test tube and filled with dry nitrogen and kept at 140 ° C.

  Hexamethylene diisocyanate (manufactured by Tokyo Chemical Industry Co., Ltd.): 1.02 g, ε-caprolactam (manufactured by Wako Pure Chemical Industries, Ltd.): 130.55 g, microcrystalline wax Hi-Mic-1080 (manufactured by Nippon Seiwa Co., Ltd.): 21 g and 10 g of the microcapsules of Production Example 1 were placed in a 300 mL Erlenmeyer flask, filled with dry nitrogen, and kept at 140 ° C.

  With the solution in the test tube and the solution in the Erlenmeyer flask at 140 ° C., the solution in the test tube was quickly poured into the Erlenmeyer flask and sufficiently stirred. After stirring, the stirring solution was poured into a polymerization tube (mold) having an inner diameter of 50 mm installed in an oil bath maintained at 160 ° C. A cured product of MC polyamide 6 was obtained in about 1 to 2 minutes, and a molded body of the composition for sliding member was obtained by allowing to stand for 1 hour. The obtained molded body was cooled to room temperature over 2 hours. A cylindrical sliding member having an outer diameter of φ5.5 mm was obtained by cutting the obtained molded product of φ50 mm. This sliding member was used for the following evaluation as a test piece.

(Evaluation)
Using a pin-on-disk type friction and wear tester (manufactured by Starlight Kogyo Co., Ltd., auto pin disk APD-101), the change with time of the friction coefficient of the test piece obtained in Example 1 was measured. The test conditions were a load of 1 MPa and a sliding speed of 0.15 m / s. The counterpart materials were stainless steel (SUS440C) with a surface roughness Ra of 0.07 μm for polishing and carbon steel (S45C) with a surface roughness Ra of 0.45 μm for lathe processing. As a comparative control, Quadrant Polypenco Japan Co., Ltd., MC nylon (registered trademark) MC901 (Comparative Control 1), MC900NC (Comparative Control 2), MC703HL (Comparative Control 3) were used. These are polyamide 6 obtained by the monomer casting method, MC900NC and MC901 are general grades, and MC703HL is a sliding grade. The evaluation results are shown in FIGS.

  FIG. 1 shows the results when the counterpart material is SUS440C, and FIG. 2 is an enlarged view of the initial test time of FIG. FIG. 3 shows the results when the counterpart material is S45C, and FIG. 4 is an enlarged view of the initial test time of FIG. As can be seen from FIGS. 1 and 3, in Example 1, the friction coefficient is almost the same regardless of the surface state of the counterpart material, whereas in Comparative Examples 1 to 3, the surface roughness of the counterpart material is all. It can be seen that the coefficient of friction increases as the value increases. As can be seen from FIGS. 2 and 4, it can be seen that the friction coefficient of Example 1 does not increase from the beginning of sliding. In this way, the first lubricant that is configured to act at the beginning of sliding and the second lubricant that is configured to act after the initial stage of sliding, which is higher in viscosity than the first lubricant, It can be seen that in the region where adhesive wear occurs, good lubricity is exhibited regardless of the surface condition of the counterpart material, and the lubricity can be maintained for a long period of time at the initial stage of sliding and thereafter.

(Example 2): 5.0% by mass of microcapsules, 15.4% by mass of second lubricant
[epsilon] -caprolactam Na salt (manufactured by Biosynth): 4.57 g, [epsilon] -caprolactam (manufactured by Wako Pure Chemical Industries, Ltd.): 47.41 g was taken in a test tube and filled with dry nitrogen and kept at 140 [deg.] C.

  Hexamethylene diisocyanate (manufactured by Tokyo Chemical Industry Co., Ltd.): 1.49 g, ε-caprolactam (manufactured by Wako Pure Chemical Industries, Ltd.): 106.48 g, microcrystalline wax Hi-Mic-1080 (manufactured by Nippon Seiwa Co., Ltd.): 31 g and 10 g of the microcapsules of Production Example 1 were placed in a 300 mL Erlenmeyer flask, filled with dry nitrogen, and kept at 140 ° C.

  Thereafter, in the same manner as in Example 1, a sliding member having an outer diameter of φ5.5 mm was obtained. Using this as a test piece, the same “evaluation” as in Example 1 was performed. However, the counterpart material was only stainless steel (SUS440C) having a polishing surface roughness Ra of 0.07 μm. The evaluation results are shown in FIGS.

(Comparative Control 4): Microcapsule: 0% by mass, second lubricant 9.7% by mass
[epsilon] -caprolactam Na salt (manufactured by Biosynth): 4.21 g, [epsilon] -caprolactam (manufactured by Wako Pure Chemical Industries, Ltd.): 51.19 g were taken in a test tube and filled with dry nitrogen and kept at 140 [deg.] C.

  Hexamethylene diisocyanate (manufactured by Tokyo Chemical Industry Co., Ltd.): 0.9 g, ε-caprolactam (manufactured by Wako Pure Chemical Industries, Ltd.): 129.19 g, microcrystalline wax Hi-Mic-1080 (manufactured by Nippon Seiwa Co., Ltd.): 20 g was placed in a 300 mL Erlenmeyer flask, filled with dry nitrogen, and maintained at 140 ° C.

  Thereafter, in the same manner as in Example 1, a sliding member having an outer diameter of φ5.5 mm was obtained. Using this as a test piece, the same “evaluation” as in Example 1 was performed. However, the counterpart material was only stainless steel (SUS440C) having a polishing surface roughness Ra of 0.07 μm. The evaluation results are shown in FIGS.

(Comparative Control 5): Microcapsule: 0% by mass, second lubricant 13.6% by mass
[epsilon] -caprolactam Na salt (manufactured by Biosynth): 4.27 g, [epsilon] -caprolactam (manufactured by Wako Pure Chemical Industries, Ltd.): 50.41 g was taken in a test tube and filled with dry nitrogen and kept at 140 [deg.] C.

  Hexamethylene diisocyanate (manufactured by Tokyo Chemical Industry Co., Ltd.): 0.76 g, ε-caprolactam (manufactured by Wako Pure Chemical Industries, Ltd.): 134.63 g, microcrystalline wax Hi-Mic-1080 (manufactured by Nippon Seiwa Co., Ltd.): 30 g was placed in a 300 mL Erlenmeyer flask, filled with dry nitrogen, and maintained at 140 ° C.

  Thereafter, in the same manner as in Example 1, a sliding member having an outer diameter of φ5.5 mm was obtained. Using this as a test piece, the same “evaluation” as in Example 1 was performed. However, the counterpart material was only stainless steel (SUS440C) having a polishing surface roughness Ra of 0.07 μm. The evaluation results are shown in FIGS.

  FIG. 5 is a diagram showing the change over time in the friction coefficient of the test piece obtained in Example 2, and FIG. 6 is an enlarged view of the initial test time of FIG. FIG. 7 is a diagram showing a change with time of the friction coefficient of the test pieces obtained in Comparative Controls 4 and 5, and FIG. 8 is an enlarged view of the initial test time of FIG. As can be seen from FIGS. 5 and 6, when the content of the second sliding member is increased from Example 1 to a predetermined value, comparisons 1 to 3 shown in FIGS. 1 and 2 and comparisons shown in FIGS. Compared to control 5, the friction coefficient at the initial stage of sliding is low, and the coefficient of friction has not increased from the initial stage of sliding, and it can be seen that the lubricity can be maintained for a long period of time at the initial stage of sliding and thereafter. . Moreover, from the comparison between Example 1 and Comparative Example 4, and Example 2 and Comparative Example 5 shown in FIGS. 1 to 6, a first lubricant having a predetermined configuration and a second lubricant having a predetermined configuration are used in combination. It can be seen that the desired effect can be obtained.

(Comparison 6-10)
The obtained test piece with the comparator 4, petroleum oils on the sliding surface (kinematic viscosity at 40 ℃: 29.9mm ² / s) that is 0.6~0.7mL attaching (comparative 6 ), Aromatic glycol-based or ether-based oil (kinematic viscosity at 40 ° C .: 15.8 mm ² / s) adhered to the sliding surface 0.6 to 0.7 mL (Comparative Control 7), sliding A silicone oil 1 (kinematic viscosity at 40 ° C .: 4000 mm ² / s) attached to the surface (0.6 to 0.7 mL) (Comparative Control 8), and a silicone oil 2 (kinematic viscosity at 40 ° C. at the sliding surface) : 1335 mm ² / s) with 0.6 to 0.7 mL attached (Comparative Control 9), and with 0.7 mg of microcrystalline wax attached to the sliding surface (Comparative Control 10) Evaluation was performed in the same manner as in 1. The evaluation results are shown in FIGS.

  9 to 13 are diagrams showing changes with time in the friction coefficients of Comparative Controls 6 to 10, respectively. As shown in FIGS. 9 and 10, instead of the first lubricant having a predetermined configuration, petroleum-based oil or aromatic glycol-based or ether-based oil as the first lubricant is directly added to the sliding surface separately. In this case, the friction coefficient as low as that of Example 1 is maintained from the start of the test to a certain period, but it can be seen that the friction coefficient increases after that. In addition, as shown in FIGS. 11 and 12, in the case where silicone oil as the first lubricant is directly added to the sliding surface instead of the first lubricant having a predetermined configuration, Example 1 is started from the start of the test. It can be seen that the coefficient of friction is higher. Furthermore, as shown in FIG. 13, when the petroleum-based wax as the second lubricant was added directly to the sliding surface without using the first lubricant having a predetermined configuration, from the start of the test, Example 1 It can be seen that the coefficient of friction is high. From these results, it can be seen that by including the first lubricant as a predetermined configuration as in Example 1, for example, the lubricity can be maintained over a long period of time at the initial stage of sliding and thereafter.

  On the other hand, as shown in FIGS. 9 and 10, in Comparative Controls 6 and 7, a low coefficient of friction was maintained from the start of the test to a certain period, whereas as shown in FIGS. In Controls 8 and 9, it can be seen that the friction coefficient is high from the start of the test. In these results and Comparative Example 4, considering that petroleum wax is contained as the second lubricant, petroleum-derived oil that is the same petroleum lubricant as the second lubricant is applied to the sliding surface. It can be said that the comparison 6 added and the comparison 7 added with glycol-based or ether-based oil on the sliding surface suggest that the friction coefficient can be kept low in the presence thereof. .

(Example 3): Petroleum oil-supported graphite 4.6% by mass, second lubricant 9.7% by mass
A sliding member having an outer diameter of φ5.5 mm was obtained in the same manner as in Example 1 except that the microcapsule obtained in Production Example 1 was replaced with graphite carrying the petroleum oil obtained in Production Example 2. Got. Using this as a test piece, the same “evaluation” as in Example 1 was performed. However, the counterpart material was only stainless steel (SUS440C) having a polishing surface roughness Ra of 0.07 μm. The evaluation results are shown in FIG.

  From the results shown in FIG. 14, it can be seen that even when the first lubricant is supported on the porous fine particles, the lubricity can be maintained for a long period of time at the initial stage of sliding and thereafter.

(Example 4)
46% by weight of novolac-type phenolic resin (manufactured by Sumitomo Bakelite Co., Ltd., Sumilite Resin (registered trademark) PR-50252), 4% by weight of cross-linking agent (hexamine), 38% by weight of solvent (methanol), obtained in Production Example 1 A varnish (composition for sliding member) of 4% by weight of microcapsules and 8% by weight of a second lubricant (manufactured by Nippon Seiwa Co., Ltd., NPS-9210 250 μm or less) was prepared. After impregnating this varnish with a cotton cloth (manufactured by Toko Kosen Co., Ltd., No. 11, canvas, density: 340 g / m ² , thickness: 0.6 mm, tensile strength: 30 N / mm ² ), the varnish was dried at 70 ° C. for 60 minutes and prepreg Got. The impregnation ratio of the phenol resin containing the microcapsules and the second lubricant in the prepreg was set to 50%. After 22 layers of prepregs were laminated in the thickness direction, they were heated and pressurized at 180 ° C. and 5 MPa for 60 minutes to obtain a molded body composed of the sliding member composition and cotton cloth. By cutting this molded body, a cylindrical sliding member having an outer diameter of φ5.5 mm was obtained. “Evaluation” was performed in the same manner as in Example 1 except that the sliding member was a test piece and the test condition was that the load was 0.83 MPa.

(Comparison 11)
A sliding member was obtained and evaluated in the same manner as in Example 4 except that the varnish was prepared by adding 38% by weight of the solvent and 50% by weight of the solvent without adding the microcapsules and the second lubricant.

(Comparative Control 12)
A sliding member was obtained and evaluated in the same manner as in Example 4 except that the varnish was prepared by adding 38% by weight of solvent and 42% by weight without adding microcapsules.

The evaluation results of Example 4 and Comparative Controls 11 and 12 are shown in FIGS. FIG. 16 is an initial enlarged view of the test time of FIG. As shown in FIGS. 15 and 16, even when a thermosetting resin such as a phenol resin is used, the first and second lubricants are included in the same manner as in Examples 1 to 3, so that the initial sliding and that It turns out that lubricity can be maintained over a long period thereafter.

Claims (11)

  Sliding comprising a base material, a first lubricant configured to act at the beginning of sliding, and a second lubricant configured to act after the initial sliding and having a higher viscosity than the first lubricant Composition for members.   The composition for a sliding member according to claim 1, wherein the second lubricant is a solid lubricant.   The composition for a sliding member according to claim 1 or 2, wherein the first lubricant is supported on a carrier.   The composition for a sliding member according to claim 3, wherein the first lubricant is configured such that liquid lubricant is contained in the microcapsule.   Both the first lubricant and the second lubricant are a combination of silicone lubricants, petroleum lubricants, synthetic hydrocarbon lubricants or fluorine lubricants, or a petroleum lubricant and The composition for a sliding member according to any one of claims 1 to 4, which is a combination of a glycol-based or ether-based lubricant.   The first lubricant contains, as a main component, at least one selected from silicone oil, petroleum oil, fluorine oil, glycol or ether oil, and synthetic hydrocarbon oil, and the second lubricant The composition for a sliding member according to any one of claims 1 to 5, comprising at least one selected from silicone wax, petroleum wax, fluorine wax and synthetic hydrocarbon wax as a main component. .   The composition for a sliding member according to any one of claims 1 to 6, wherein the substrate contains a resin component.   8. The sliding member according to claim 7, wherein the resin component is at least one selected from polyamide, polyolefin, polyphenylene sulfide, polyacetal, polyether ether ketone, polyether imide, fluororesin, phenol resin, epoxy resin, and urethane resin. Composition   The sliding member containing the molded object of the composition for sliding members as described in any one of Claims 1-8.   A bearing comprising the sliding member according to claim 9. A gear comprising the sliding member according to claim 9.