WO2019225086A1

WO2019225086A1 - Sliding member and method for manufacturing sliding member

Info

Publication number: WO2019225086A1
Application number: PCT/JP2019/006472
Authority: WO
Inventors: 広一上岡; 隆浩藤本; 寿大木; 将人馬場
Original assignee: 住友電工ファインポリマー株式会社; 住友電気工業株式会社
Priority date: 2018-05-22
Filing date: 2019-02-21
Publication date: 2019-11-28
Also published as: JP2021137963A

Abstract

A sliding member according to one aspect of the present disclosure is provided with a base layer, an intermediate layer and a sliding layer in this order, wherein the main component of the intermediate layer is a hot-melt fluororesin and the main component of the sliding layer is polytetrafluoroethylene.

Description

Sliding member and method of manufacturing sliding member

The present disclosure relates to a sliding member and a method for manufacturing the sliding member.
This application claims priority based on Japanese Patent Application No. 2018-97569 filed on May 22, 2018, and incorporates all the content described in the above Japanese application.

Polytetrafluoroethylene (PTFE) is excellent in mechanical strength, chemical resistance, slipperiness, heat resistance, wear resistance, weather resistance, non-flammability, etc., and is used to constitute the surface layer of sliding members It is done.

However, in general, a film containing PTFE as a main component (PTFE film) is difficult to firmly adhere to other members. Therefore, when a layer containing PTFE is laminated on another layer, the surface of the other layer to be laminated is roughened to increase the lamination area, or a dispersion in which PTFE powder is dispersed in a dispersant. The method of apply | coating to another layer and drying the said dispersing agent is employ | adopted.

Also, as a method for increasing the adhesion between the PTFE film and other layers, a method of plasma-treating the laminated surface with the other layers of the PTFE film is also employed (see JP-A-2015-189934).

JP2015-189934A

A sliding member according to an aspect of the present disclosure includes a base material layer, an intermediate layer, and a sliding layer in this order, the main component of the intermediate layer is a heat-meltable fluororesin, and the main component of the sliding layer Is polytetrafluoroethylene.

The manufacturing method of the sliding member concerning one mode of this indication heats the layered product laminated by the process of laminating an intermediate layer and a sliding layer in this order on one side of a base material layer, and the above-mentioned lamination process A step in which the main component of the intermediate layer is a heat-meltable fluororesin, the main component of the sliding layer is polytetrafluoroethylene, and in the heating step, the laminate is a melting point of polytetrafluoroethylene. Heat to above.

It is a typical sectional view showing a sliding member concerning one embodiment of this indication. It is a flowchart which shows the manufacturing method of the sliding member which concerns on one Embodiment of this indication.

[Problems to be solved by the present disclosure]
When the surface of the other layer is roughened, equipment for roughening is required, resulting in an increase in manufacturing cost. In addition, according to this method, the use is limited because the smoothness of the laminated surface is lowered.

Also, when a dispersion containing PTFE powder is used, a special facility is required, so that the manufacturing cost increases, and the production efficiency may decrease due to clogging of the powder.

Further, when the laminated surface of the PTFE film is plasma-treated as described in the above publication, the manufacturing cost increases because special equipment is required, and the PTFE film has a modified surface due to the modification of the laminated surface of the PTFE film. There is a risk of quality degradation.

The present disclosure has been made based on such circumstances, and a sliding member and a sliding member that can increase the adhesion of a sliding layer containing PTFE as a main component while suppressing deterioration in quality. It is an object to provide a method.

[Effects of the present disclosure]
The sliding member and the manufacturing method of the sliding member according to the embodiment of the present disclosure can increase the adhesion of the sliding layer containing PTFE as a main component while suppressing deterioration in quality.

[Description of Embodiment of Present Disclosure]
First, embodiments of the present disclosure will be listed and described.

As a result of intensive studies by the present inventors, even when the main component of the sliding layer is PTFE, the sliding layer is laminated on the base material layer through an intermediate layer mainly composed of a heat-meltable fluororesin. Thus, it was found that the sliding layer and the base material layer can be firmly adhered. Since the sliding member increases the adhesion between the sliding layer and the base material layer by interposing the intermediate layer, it is difficult to cause a decrease in quality due to the adhesion of the sliding layer. Therefore, the said sliding member can raise the contact | adhesion power of the sliding layer which has PTFE as a main component, suppressing the deterioration of quality.

The heat-meltable fluororesin may be a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA) or a tetrafluoroethylene-hexafluoropropylene copolymer (FEP). Thus, when the said heat-meltable fluororesin is PFA or FEP, the adhesive force of the said sliding layer and a base material layer can be raised easily and reliably.

The main component of the base material layer is preferably a liquid crystal polymer. Thus, when the main component of the base material layer is a liquid crystal polymer, the adhesion between the sliding layer and the base material layer can be easily and reliably increased.

The average thickness of the intermediate layer is preferably 10 μm or more and 200 μm or less. Thus, when the average thickness of the intermediate layer is within the above range, the adhesion between the sliding layer and the base material layer can be easily and reliably increased.

Moreover, the manufacturing method of the sliding member according to another aspect of the present disclosure includes a step of laminating an intermediate layer and a sliding layer in this order on one surface of the base material layer, and a laminating layer laminated in the laminating step. Heating the body, the main component of the intermediate layer is a heat-meltable fluororesin, the main component of the sliding layer is polytetrafluoroethylene, and in the heating step, the laminate is made of polytetrafluoroethylene. Heat above the melting point of fluoroethylene.

In the manufacturing method of the sliding member, in the heating step, the laminated body in which the base material layer, the intermediate layer, and the sliding layer are laminated in this order is heated to the melting point of PTFE or more. The layer can be firmly adhered. Since the manufacturing method of the sliding member increases the adhesion between the sliding layer and the base material layer by interposing the intermediate layer, it is difficult to cause a decrease in quality due to the adhesion of the sliding layer. . Therefore, the manufacturing method of the said sliding member can raise the adhesive force of the said sliding layer and base material layer, suppressing the deterioration of quality.

In the present disclosure, the “main component” refers to a component having the largest content ratio in terms of mass, for example, a component having a content ratio of 50% by mass or more. “Average thickness” means an average value of thicknesses at arbitrary 10 points. “Melting point” refers to a melting point peak temperature measured by a differential scanning calorimeter (DSC) in accordance with JIS-K7121: 2012 “Method for measuring plastic transition temperature”.

[Details of Embodiment of the Present Disclosure]
Hereinafter, the sliding member and the manufacturing method of the sliding member according to each embodiment of the present disclosure will be described in detail with reference to the drawings.

<Sliding member>
The sliding member of FIG. 1 includes a base material layer 1, an intermediate layer 2, and a sliding layer 3 in this order. The main component of the intermediate layer 2 is a heat-meltable fluororesin. The main component of the sliding layer 3 is PTFE.

As a result of intensive studies by the present inventors, even when the main component of the sliding layer 3 is PTFE, the sliding layer 3 is attached to the base material layer 1 via the intermediate layer 2 mainly composed of a heat-meltable fluororesin. It turned out that the sliding layer 3 and the base material layer 1 can be adhere | attached firmly by laminating | stacking. The sliding member increases the adhesion between the sliding layer 3 and the base material layer 1 by interposing the intermediate layer 2, and roughens or slides the facing surfaces of the sliding layer 3 and the base material layer 1. Since no modification treatment or the like of the moving layer 3 is required, it is difficult to cause quality deterioration due to the close contact of the sliding layer 3. Therefore, the said sliding member can raise the contact | adhesion power of the sliding layer 3 which has PTFE as a main component, suppressing the deterioration of quality. Moreover, since the said sliding member does not require the equipment for the roughening of the opposing surface of the sliding layer 3 and the base material layer 1, and the modification | reformation of the sliding layer 3, manufacturing cost can be suppressed.

The sliding member is used as a member such as a fixing roller or a bearing. The base material layer 1, the intermediate layer 2, and the sliding layer 3 are directly laminated. In the sliding member, the base material layer 1, the intermediate layer 2, and the sliding layer 3 are firmly adhered to each other. Specifically, the interface fracture occurs at each interface of the base material layer 1, the intermediate layer 2, and the sliding layer 3. It adheres to such an extent that it does not produce. The sliding layer 3 constitutes the outermost layer of the sliding member. That is, the said sliding member has the sliding layer 3, the intermediate | middle layer 2, and the base material layer 1 in this order from the outermost surface side. The sliding member may further include another layer on the back surface side of the base material layer 1 (the side opposite to the side on which the intermediate layer 2 is laminated). In addition, in FIG. 1, a planar sheet-like configuration is illustrated, but the shape of the sliding member is not particularly limited, for example, a shape having a curved surface such as a cylindrical shape or an arch shape. The shape may be other than the sheet shape.

(Sliding layer)
The sliding layer 3 has PTFE as a main component as described above. This PTFE is preferably crosslinked by, for example, irradiation with ionizing radiation. The sliding layer 3 can enhance wear resistance by cross-linking PTFE.

The laminated surface of the sliding layer 3 with the intermediate layer 2 is preferably not modified. The sliding member is provided with the intermediate layer 2 between the sliding layer 3 and the base material layer 1 so that the surface of the sliding layer 3 on the base material layer 1 side (lamination surface with the intermediate layer 2). Even when not modified, the adhesion between the sliding layer 3 and the base material layer 1 can be sufficiently increased. Moreover, the said sliding member can prevent the fall of the quality of the sliding layer 3 resulting from modification | reformation because the sliding layer 3 is not modified | denatured.

The laminated surface of the sliding layer 3 with the intermediate layer 2 is preferably not roughened. The sliding member is provided with the intermediate layer 2 between the sliding layer 3 and the base material layer 1 so that the surface of the sliding layer 3 on the base material layer 1 side (lamination surface with the intermediate layer 2). Even when the surface is not roughened, the adhesion between the sliding layer 3 and the base material layer 1 can be sufficiently increased. Moreover, the said sliding member can prevent that a use application is limited by roughening by not roughening the lamination | stacking surface with the intermediate | middle layer 2 of the sliding layer 3. FIG. In the case where the laminated surface of the sliding layer 3 with the intermediate layer 2 is not roughened, the upper limit of the arithmetic average roughness Ra of the laminated surface of the sliding layer 3 with the intermediate layer 2 is preferably 0.50 μm, for example. 10 μm is more preferable, and 0.05 μm is even more preferable. Moreover, as a minimum of arithmetic mean roughness Ra of the laminated surface with the intermediate | middle layer 2 of the sliding layer 3, it can be set to 0 micrometer. The “arithmetic mean roughness Ra” means a value measured with a cutoff value (λc) of 2.5 mm and an evaluation length (l) of 8 mm in accordance with JIS-B0601: 2001.

PTFE may contain polymerized units derived from other copolymerizable monomers as long as the effects of the present disclosure are not impaired. For example, perfluoro (alkyl vinyl ether), hexafluoropropylene, (perfluoroalkyl) ethylene, It may contain polymerized units such as chlorotrifluoroethylene. As an upper limit of the content rate of the polymerization unit derived from said other copolymerizable monomer, it can be set as 3 mol%, for example.

The content ratio of PTFE in the sliding layer 3 is 50% by mass or more. As a minimum of the above-mentioned content rate, 60 mass% is preferred, 85 mass% is more preferred, and 98 mass% is still more preferred. The content is particularly preferably 100% by mass. If the content is less than the lower limit, characteristics such as wear resistance and heat resistance may not be sufficiently improved.

The sliding layer 3 may contain other optional components. Examples of the optional component include a solid lubricant and a reinforcing material. When the sliding layer 3 contains a solid lubricant, a reinforcing material, etc., the slipperiness can be further improved. Examples of the solid lubricant include molybdenum disulfide. Examples of the reinforcing material include glass fillers such as glass fiber (glass fiber) and spherical glass, and inorganic fillers such as carbon fiber, calcium carbonate, talc, silica, alumina, and aluminum hydroxide.

The lower limit of the melting point (crystal melting point) of PTFE is preferably 320 ° C. When the melting point is smaller than the lower limit, the wear resistance may be insufficient due to a decrease in heat resistance or the like. On the other hand, the upper limit of the melting point is, for example, preferably 340 ° C., and more preferably 335 ° C. Moreover, as typical melting | fusing point of this PTFE, 327 degreeC is mentioned, for example.

The lower limit of the average thickness of the sliding layer 3 is preferably 50 μm, more preferably 100 μm. On the other hand, the upper limit of the average thickness of the sliding layer 3 is preferably 1000 μm, more preferably 700 μm, and even more preferably 500 μm. If the average thickness is less than the lower limit, the durability of the sliding layer 3 may be insufficient. On the contrary, when the average thickness exceeds the upper limit, the flexibility of the sliding layer 3 is lowered, and there is a possibility that the usage is limited.

(Middle layer)
The intermediate layer 2 is an adhesive layer that bonds the base material layer 1 and the sliding layer 3 together. Since the sliding layer 3 contains PTFE as a main component, it is difficult to directly adhere to the base material layer 1. In contrast, according to the knowledge of the present inventors, the sliding layer 3 can be firmly adhered to the base material layer 1 by surprisingly interposing the intermediate layer 2 as an adhesive layer.

The intermediate layer 2 may be partially disposed between the base material layer 1 and the sliding layer 3, but from the viewpoint of increasing the adhesion between the base material layer 1 and the sliding layer 3, the base material layer 1 and It is preferable to be disposed in the entire region between the sliding layers 3.

As described above, the intermediate layer 2 is mainly composed of a heat-meltable fluororesin. Examples of the heat-meltable fluororesin include PFA and FEP. The sliding member can easily and reliably increase the adhesion between the sliding layer 3 and the base material layer 1 by the intermediate layer 2 when the heat-meltable fluororesin is PFA or FEP. In addition, the said heat-meltable fluororesin may contain the polymer unit derived from another copolymerizable monomer in the range which does not impair the effect of this indication. Moreover, the intermediate | middle layer 2 may contain another arbitrary component in the range which does not impair the effect of this indication.

The content ratio of the heat-meltable fluororesin in the intermediate layer 2 is 50% by mass or more. As a minimum of the above-mentioned content rate, 60 mass% is preferred, 85 mass% is more preferred, and 98 mass% is still more preferred. The content is particularly preferably 100% by mass. If the said content rate is less than the said minimum, there exists a possibility that the adhesive force of the base material layer 1 and the sliding layer 3 cannot fully be raised.

In the intermediate layer 2, the heat-meltable fluororesin may not be cross-linked or may be cross-linked. The melting point of the hot-melt fluororesin is lower than the melting point of PTFE. The melting point of PFA is, for example, 304 ° C. or higher and 310 ° C. or lower. The melting point of FEP is, for example, 270 ° C.

The lower limit of the average thickness of the intermediate layer 2 is preferably 10 μm, and more preferably 25 μm. On the other hand, the upper limit of the average thickness of the intermediate layer 2 is preferably 200 μm, and more preferably 150 μm. If the average thickness is less than the lower limit, the adhesion between the sliding layer 3 and the base material layer 1 may not be sufficiently increased. On the other hand, if the average thickness exceeds the upper limit, the thickness of the intermediate layer 2 becomes unnecessarily large, which may increase the manufacturing cost. On the other hand, when the average thickness is within the above range, the heat-meltable fluororesin appropriately flows when the base material layer 1, the intermediate layer 2, and the sliding layer 3 are bonded by heating. Thus, the gap between the bonding surface of the base material layer 1 and the intermediate layer 2 and the bonding surface of the intermediate layer 2 and the sliding layer 3 is filled. Thereby, the base material layer 1 and the intermediate | middle layer 2, and the intermediate | middle layer 2 and the sliding layer 3 can respectively adhere | attach the whole surface, and the adhesive force of the base material layer 1, the intermediate | middle layer 2, and the sliding layer 3 is made. It can be raised enough.

It is preferable that both surfaces of the intermediate layer 2 are not modified. Moreover, it is preferable that both surfaces of the intermediate | middle layer 2 are not roughened. When both surfaces of the intermediate layer 2 are not roughened, the upper limit of the arithmetic average roughness Ra of both surfaces of the intermediate layer 2 is, for example, preferably 0.50 μm, more preferably 0.10 μm, and even more preferably 0.05 μm. . Moreover, as a minimum of arithmetic mean roughness Ra of the intermediate | middle layer 2, it can be set to 0 micrometer.

(Base material layer)
The base material layer 1 is mainly composed of, for example, metal or super engineering plastic. When the main component of the base material layer 1 is the said metal, the base material layer 1 may be foil shape and may be plate shape. When the main component of the base material layer 1 is a super engineering plastic, the base material layer 1 is, for example, a flexible film. Note that the "super engineering plastics", long-term heat resistance is 100 ° C. or higher, the thermal deformation temperature of 0.99 ° C. or higher, a tensile strength of 5 kgf · ^{mm -2} or more and flexural synthesis modulus of 245kgf · ^{mm -2} or more Refers to resin. However, the synthetic resin which has a fluororesin as a main component is not included.

Examples of the metal include aluminum, an aluminum alloy, copper, a copper alloy, an iron alloy such as iron and stainless steel, and nickel. Examples of the super engineering plastic include polyimide (PI), polyamideimide (PAI), polyetherimide (PEI), polyetheretherketone (PEEK), polyphenylene sulfide (PPS), polyarylate (PAR), and liquid crystal polymer (LCP). ), Polysulfone (PSF), polyethersulfone (PES), and the like. These can be used alone or in combination of two or more. Especially, as a main component of the base material layer 1, a liquid crystal polymer is preferable. Since the main component of the base material layer 1 is a liquid crystal polymer, the adhesion between the sliding layer 3 and the base material layer 1 can be easily and reliably increased by interposing the intermediate layer 2.

The average thickness of the base material layer 1 can be appropriately set according to the use application of the sliding member, and the lower limit thereof is preferably 10 μm, for example, and more preferably 100 μm. When the average thickness is smaller than the lower limit, the strength of the base material layer 1 may be insufficient. On the other hand, as an upper limit of the average thickness of the base material layer 1, it can be 10 cm, for example.

The laminated surface of the base material layer 1 with the intermediate layer 2 is preferably not roughened. The sliding member is provided with the intermediate layer 2 between the sliding layer 3 and the base material layer 1, so that even when the base material layer 1 is not roughened, the sliding layer 3 and the base material layer 1 Can be sufficiently enhanced. Moreover, the said sliding member prevents that the use application is limited by roughening by not roughening the surface by the side of the sliding layer 3 of the base material layer 1 (lamination surface with the intermediate | middle layer 2). can do. When the laminated surface of the base material layer 1 with the intermediate layer 2 is not roughened, the upper limit of the arithmetic average roughness Ra of the laminated surface of the base material layer 1 with the intermediate layer 2 is, for example, preferably 0.50 μm, 0 10 μm is more preferable, and 0.05 μm is even more preferable. Moreover, as a minimum of arithmetic mean roughness Ra of the laminated surface with the intermediate | middle layer 2 of the base material layer 1, it can be set to 0 micrometer.

In the sliding member, when the 180 ° peel test of the sliding layer 3 is performed, it is preferable that the base material layer 1 causes material destruction. In the sliding member, the adhesion between the intermediate layer 2 and the base material layer 1 and between the intermediate layer 2 and the sliding layer 3 is increased, so that the interface between the intermediate layer 2 and the base material layer 1 and the intermediate layer 2 are increased. And peeling at the interface with the sliding layer 3 can be prevented.

<Sliding member manufacturing method>
Then, with reference to FIG. 2, the manufacturing method of the sliding member of FIG. 1 is demonstrated. The manufacturing method of the said sliding member heats the laminated body laminated | stacked by the process (lamination process) which laminates | stacks the intermediate | middle layer 2 and the sliding layer 3 in this order on one surface of the base material layer 1, and the said lamination process. A process (heating process). The main component of the intermediate layer 2 is a heat-meltable fluororesin, and the main component of the sliding layer 3 is PTFE. The manufacturing method of the said sliding member heats the said laminated body more than melting | fusing point of PTFE at the said heating process.

According to the knowledge of the present inventors, even if the main component of the sliding layer 3 is PTFE, a laminate in which the base material layer 1, the intermediate layer 2, and the sliding layer 3 are laminated in this order is PTFE. The sliding layer 3 and the base material layer 1 can be firmly adhered by heating to the melting point or higher. Since the manufacturing method of the sliding member increases the adhesion between the sliding layer 3 and the base material layer 1 by interposing the intermediate layer 2, the quality deteriorates due to the adhesion of the sliding layer 3. hard. Therefore, the manufacturing method of the said sliding member can raise the adhesive force of the sliding layer 3 and the base material layer 1 easily and reliably, suppressing the deterioration of quality. Moreover, since the manufacturing method of the said sliding member does not require the roughening of the opposing surface of the sliding layer 3 and the base material layer 1, or modification | reformation of the sliding layer 3, it can suppress manufacturing cost. it can.

(Lamination process)
In the laminating step, the base material layer 1, the intermediate layer 2, and the sliding layer 3 are directly laminated in this order. More specifically, in the laminating step, a base material layer forming film or base material layer forming plate material for forming the base material layer 1 of the sliding member of FIG. The material layer forming plate materials are collectively referred to as the base layer forming film), the intermediate layer forming film for forming the intermediate layer 2, and the sliding layer forming film for forming the sliding layer 3 in this order. Laminate directly. The components and average thickness of the base layer forming film are the same as those of the base layer 1 in FIG. The components and average thickness of the intermediate layer forming film are the same as those of the intermediate layer 2 in FIG. The components and average thickness of the sliding layer forming film are the same as those of the sliding layer 3 in FIG. In addition, in the said lamination process, you may further laminate | stack another layer etc. on the surface on the opposite side to the lamination surface with the intermediate | middle layer 2 of the base material layer 1. FIG.

The laminated surface of the sliding layer forming film laminated with the intermediate layer forming film laminated in the laminating step and the laminated surface of the base material layer forming film with the intermediate layer forming film are not modified. preferable. That is, it is preferable that the manufacturing method of the said sliding member does not have the process of modifying the surface of the said film for sliding layer formation, and the surface of the said film for base material layer formation.

The laminated surface of the sliding layer forming film laminated with the intermediate layer forming film and the laminated surface of the substrate layer forming film with the intermediate layer forming film laminated in the laminating step are roughened. Preferably not. That is, it is preferable that the manufacturing method of the said sliding member does not have the process of roughening the surface of the said film for sliding layer formation, and the surface of the said film for base material layer formation.

(Heating process)
In the heating step, the base material layer 1, the intermediate layer 2, and the sliding layer 3 laminated in the laminating step as described above are heated to the melting point of PTFE or higher. In the heating step, the laminate may be pressed at the same time as the laminate is heated to the melting point of PTFE or higher. When pressing the laminate, surface treatment such as embossing can be applied to the surface of the laminate by imparting a desired shape to the surface of the pressing mold. In addition, when PTFE contained in the sliding layer 3 manufactured by the manufacturing method of the said sliding member is bridge | crosslinked, it is preferable that PTFE is bridge | crosslinked before the said heating process. Moreover, when PFA and / or FEP contained in the intermediate layer 2 manufactured by the manufacturing method of the sliding member are cross-linked, it is preferable that PFA and / or FEP be cross-linked before the heating step.

In the heating step, for example, the laminated body is heated in a heating furnace. The heating atmosphere temperature in the heating step is equal to or higher than the melting point of PTFE. As the lower limit of the heating atmosphere temperature, a temperature 5 ° C. higher than the melting point of PTFE is preferable, and a temperature 10 ° C. higher than the melting point of PTFE is more preferable. Specifically, when the melting point of PTFE is 327 ° C., the lower limit of the heating atmosphere temperature in the heating step is preferably 332 ° C. and more preferably 337 ° C. According to the manufacturing method of the sliding member, PTFE becomes partially rubbery on the bonding surface of the sliding layer 3 and the intermediate layer 2 by the heating step, and the hot-melt fluororesin is partially melted and decomposed. Thus, it is considered that the adhesive force between the sliding layer 3 and the intermediate layer 2 is enhanced due to the branched molecular structure of the heat-meltable fluororesin. Therefore, if the heating atmosphere temperature is less than the lower limit, PTFE cannot be sufficiently softened, and the adhesive strength between the sliding layer 3 and the intermediate layer 2 may be insufficient. In addition, as an upper limit of the heating atmosphere temperature in the said heating process, the temperature 50 degreeC higher than the melting point of PTFE is preferable, for example, and the temperature 40 degreeC higher than the melting point of PTFE is more preferable. Specifically, when the melting point of PTFE is 327 ° C., the upper limit of the heating atmosphere temperature in the heating step is preferably 377 ° C. and more preferably 367 ° C. When the heating atmosphere temperature exceeds the upper limit, the heating temperature in the heating step becomes unnecessarily high, which may increase the production cost, and may cause the hot-melt fluororesin to be melted and decomposed excessively.

The lower limit of the heating time in the heating step is preferably 1 minute. On the other hand, the upper limit of the heating time in the heating step is preferably 90 minutes, and more preferably 70 minutes. If the heating time is less than the lower limit, PTFE may not be heated at a sufficient heating temperature. On the contrary, when the heating time exceeds the upper limit, the heating time in the heating step becomes unnecessarily long, which may increase the manufacturing cost, and may cause the hot-melt fluororesin to be melted and decomposed excessively. Moreover, when the said heating time exceeds the said upper limit, it will become easy to produce hydrofluoric acid by decomposition | disassembly of the said heat-meltable fluororesin. Therefore, for example, when the main component of the film for forming a base layer is a metal, the metal is corroded by the hydrofluoric acid, and the mechanical strength of the base layer 1 may be reduced.

The heating step may be performed in a pressurized atmosphere or a reduced pressure atmosphere. In the heating step, the adhesion between the intermediate layer 2 and the base material layer 1 and between the intermediate layer 2 and the sliding layer 3 due to expansion of bubbles such as hydrogen fluoride gas generated by the decomposition of the hot-melting fluororesin. There is a possibility that the In this regard, the intermediate layer 2, the base material layer 1, and the intermediate layer 2 are compressed by compressing bubbles by performing the heating step in a pressurized atmosphere, or by degassing by performing the heating step in a reduced pressure atmosphere. The adhesion force between the layer 2 and the sliding layer 3 can be more reliably increased.

The heating step is also preferably performed in a vacuum atmosphere or a nitrogen atmosphere. By performing the heating step in a vacuum atmosphere or a nitrogen atmosphere, oxidation of the metal can be prevented when the main component of the base layer forming film is a metal, and the mechanical strength of the base layer 1 Can be prevented.

(Other processes)
The manufacturing method of the said sliding member may be equipped with the process (washing | cleaning process) of wash | cleaning the lamination | stacking surface with the film for intermediate | middle layer formation of the said base material layer formation film before the said lamination process. The manufacturing method of the said sliding member removes the foreign material, stain | pollution | contamination, etc. of a lamination surface with the film for intermediate | middle layer formation of the said film for base material layer formation by providing the said washing | cleaning process, and the base material layer 1 and intermediate | middle layer 2 can be easily and reliably increased. In addition, the manufacturing method of the sliding member includes the step of laminating the intermediate layer forming film with the base layer forming film and / or the sliding layer forming film before the laminating step, or forming the sliding layer. You may provide the process of wash | cleaning the lamination | stacking surface with the film for intermediate | middle layer formation of the film for use.

[Other Embodiments]
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is not limited to the configuration of the embodiment described above, but is defined by the scope of the claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

For example, the intermediate layer may be a multilayer body having two or more layers.

In the above embodiment, the configuration in which the base material layer is a plate shape, a foil shape, or a film shape has been described, but the base material layer may have a three-dimensional shape other than the plate shape, the foil shape, and the film shape.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

[No. 1 and no. 2]
A film for forming a base layer having a thickness of 1200 μm made of aluminum, and a film for forming an intermediate layer having a thickness of 50 μm mainly composed of PFA (melting point: 304 to 310 ° C.) (“NEOFRON (registered trademark) PFA made by Daikin Industries, Ltd.) )) And a 200 μm-thick sliding layer-forming film (“VALFLON (registered trademark)” manufactured by VALQUA INDUSTRY CO., LTD.), Which is mainly composed of uncrosslinked PTFE (melting point: 327 ° C.), were laminated in this order. (Lamination process). In addition, each laminated surface of the film for base material layer formation, the film for intermediate | middle layer formation, and the film for sliding layer formation is not roughened, and the surface treatment is not performed. The arithmetic average roughness Ra of the laminated surface of the base layer forming film and the intermediate layer forming film is 0.4 μm, the arithmetic average roughness Ra of both surfaces of the intermediate layer forming film is 0.4 μm, and the sliding layer forming The arithmetic average roughness Ra of the laminated surface of the film with the intermediate layer forming film is 0.4 μm. A stainless steel plate having a thickness of 120 μm is placed on the surface of the film for forming the sliding layer of the laminated body laminated in this lamination step, sandwiched by a crimping jig, accommodated in a heating furnace, and heated as shown in Table 1. Heated at temperature and heating time (heating step). Then, after taking out from the heating furnace and cooling to room temperature (25 degreeC), the board | plate material and the crimping | compression-bonding jig were removed and the sliding member was obtained.

[No. 3 to No. 7]
No. 1 except that the base material layer forming film of Table 1 was used instead of the base material layer forming film of No. 1. No. 1 as in No. 1. 3 to No. 7 sliding members were produced.

[No. 8 and no. 9]
Except that the heating temperature and heating time in the heating step were as shown in Table 1, A sliding member was produced in the same manner as in Example 1.

[No. 10]
In place of an intermediate layer forming film, an adhesive layer having a thickness of 50 μm made of an adhesive mainly composed of an epoxy resin (“epoxy adhesive for soft vinyl chloride 2081D” manufactured by ThreeBond Co., Ltd.) was disposed. . A sliding member was produced in the same manner as in Example 1.

<Adhesion>
A 5 mm wide intermediate layer and a sliding layer cut in a strip shape on the surface of the base material layer were laminated in this order. 1-No. Ten test pieces were prepared, a 180 ° peel test of the sliding layer and the intermediate layer was performed at room temperature (25 ° C.), and the adhesion was evaluated according to the following criteria. The evaluation results are shown in Table 2.
A: Peeling does not occur at the interface between the sliding layer and the intermediate layer (peeling strength could not be measured due to breakage of the sliding layer).
B: Peeling does not occur at the interface between the sliding layer and the intermediate layer (material destruction of the base material layer occurred at a load of 1.0 kgf / 5 mm or more).
C: Peeling does not occur at the interface between the sliding layer and the intermediate layer (material destruction of the base material layer occurred at a load of less than 1.0 kgf / 5 mm).
D: Peeling occurs at the interface between the sliding layer and the intermediate layer.

<Evaluation results>
As shown in Table 1 and Table 2, a base material layer, an intermediate layer mainly composed of a heat-meltable fluororesin, and a sliding layer mainly composed of PTFE are laminated in this order. No. obtained by heating above the melting point of PTFE. 1-No. The sliding member 7 has excellent adhesion.

1 base layer 2 intermediate layer 3 sliding layer

Claims

A base material layer, an intermediate layer, and a sliding layer are provided in this order,
The main component of the intermediate layer is a heat-meltable fluororesin,
A sliding member wherein the main component of the sliding layer is polytetrafluoroethylene.
The sliding member according to claim 1, wherein the heat-meltable fluororesin is a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer or a tetrafluoroethylene-hexafluoropropylene copolymer.
The sliding member according to claim 1 or 2, wherein a main component of the base material layer is a liquid crystal polymer.
The sliding member according to claim 1, wherein the intermediate layer has an average thickness of 10 μm or more and 200 μm or less.
A step of laminating an intermediate layer and a sliding layer in this order on one surface of the base material layer;
Heating the laminate laminated in the lamination step,
The main component of the intermediate layer is a heat-meltable fluororesin,
The main component of the sliding layer is polytetrafluoroethylene,
The manufacturing method of the sliding member which heats the said laminated body to more than melting | fusing point of polytetrafluoroethylene at the said heating process.