Resin composition for chip seal and chip seal for scroll-type refrigerant compressor

Abstract

To provide a resin composition for a chip seal which enables formation of an injection molded article having good heat resistance and abrasive resistance even if rotation speed of a scroll member is higher than conventional rotation speed, and has good moldability by injection molding of a thin and long chip seal, and a chip seal for a scroll type refrigerant compressor which is an injection molding of the resin composition for the chip seal.SOLUTION: A resin composition for a chip seal contains 70 to 90 wt.% of a polyether ether ketone resin, and 2 to 20 wt.% of an inorganic filler having Mohs hardness of 4 or more and thermal conductivity of 60 [W / m K] or less, and a solid lubricant and carbon fibers as remainders.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a resin composition for tip seals and a tip seal for scroll-type refrigerant compressors which is an injection-molded product of the resin composition for tip seals. [Background technology]

[0002] As shown in Figures 1 and 2, a scroll-type refrigerant compressor has a fixed scroll member 1 attached to the main body, and a movable scroll member 2 assembled to the fixed scroll member 1. Thin, long tip seals (scroll-type refrigerant compressor tip seals) 3 and 4 are attached along the end faces of the spiral-shaped partition walls 5 and 6 of both scroll members 1 and 2 to seal against the mating members. External power is used to revolve the movable scroll member 2 around the axis of the fixed scroll member 1, and the compression chamber formed between the partition walls 5 and 6 moves toward the center of the spiral shape, compressing the refrigerant, such as a gas. The tightness of the compression chamber is ensured by the tip seals 3 and 4, which are attached along the end faces of both scroll members 1 and 2 and come into sliding contact with the bottom faces 9 and 8 of the opposing scroll members, as described above.

[0003] As mentioned above, tip seals used in scroll-type refrigerant compressors slide in contact with the bottom surface of the scroll member to ensure the hermeticity of the compression chamber, so they are required to have wear resistance and sealing properties (hermeticity) during sliding. Furthermore, because they come into contact with the refrigerant passing through the compression chamber and slide in the presence of refrigeration oil (lubricant), they are required to be resistant to both the refrigerant and refrigeration oil (lubricant) (chemical resistance). Furthermore, because tip seals have a thin, elongated shape as shown in Figures 1 and 3, they also require moldability during injection molding.

[0004] Patent Document 1, for example, describes a spiral tip seal for scroll compressors that uses a specified refrigerant and refrigeration oil. The seal is made by molding a resin composition containing 5 to 30 volume percent of a specified carbon fiber, 1 to 30 volume percent of a specified tetrafluoroethylene resin, and the remainder being an aromatic polyether ketone resin into a spiral shape. The resin composition has a melt viscosity of 50 to 300 Pa·s under specified conditions. This tip seal is said to provide a tip seal that is superior in load-bearing capacity, wear resistance, and non-damage to mating materials, as well as excellent moldability, even when the refrigerant in a scroll refrigerant compressor is changed from chlorofluorocarbons or chlorofluorocarbon substitutes to carbon dioxide. It also describes that the resin composition may contain an inorganic compound with a Mohs hardness of 3 or less. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 4482262 Summary of the Invention [Problem to be solved by the invention]

[0006] Scroll-type refrigerant compressors are used in heat exchange devices such as automotive air conditioners and household electrical appliances. As mentioned above, scroll-type refrigerant compressors use an external power source to revolve the moving scroll. In automotive air conditioners, a belt-driven engine-belt type external power source has typically been used. However, in recent years, motor-driven, electrically-driven scroll compressors have been increasingly adopted as external power sources for scroll-type refrigerant compressors, due to reasons such as avoiding engine idling during temporary stops and minimizing the impact on driving, primarily during acceleration, and the increasing global production and sales of electric vehicles. Furthermore, various functions in modern automobiles have been electrically powered, and many electronic circuit boards are installed, and air conditioners are also used to cool these electronic circuit boards. As a result, in order to increase the processing capacity of air conditioners, the rotational speed of the moving scroll member of scroll-type refrigerant compressors needs to be increased. In particular, electric scroll compressors allow for higher scroll speeds than belt-driven engine compressors. This places a greater strain on the tip seals than conventional scroll compressors, making it necessary to maintain the airtightness of the compression chambers even at higher rotational speeds. This creates a greater need than ever before to prevent melting and wear of the tip seals caused by the high-speed rotation of the scrolls. Furthermore, aluminum alloys are used for the scrolls to reduce weight, and one of the scrolls is anodized to prevent friction between the scrolls. This anodized surface is relatively rough. Because the bottom surface (8 and 9 in Figures 1 and 4), which serves as the sliding surface for the tip seal, is relatively rough, there is concern that high-speed rotation will further exacerbate wear.

[0007] For example, the tip seal described in Patent Document 1 uses an aromatic polyetherketone resin as a base material, which is thought to prevent melting during high-speed rotation. However, aromatic polyetherketone resins are generally known to have poor moldability, and it is not necessarily easy to injection-mold a thin, long, small-cross-sectional area tip seal, such as that used in scroll-type refrigerant compressors. Patent Document 1 also describes that the resin contains a predetermined amount of carbon fiber and tetrafluoroethylene resin. However, even in this case, it is currently difficult to ensure the wear resistance required for the high-speed rotation described above while also ensuring the injection-moldability of a thin, long, small-cross-sectional area tip seal.

[0008] Therefore, an object of the present invention is to provide a resin composition for tip seals that can form injection-molded articles having good heat resistance and abrasion resistance even when the rotational speed of the scroll member is higher than conventional ones, and that also has good moldability by injection molding for thin-walled, long tip seals, and a tip seal for a scroll-type refrigerant compressor that is an injection-molded article of the resin composition for tip seals. [Means for solving the problem]

[0009] The present inventors have conducted extensive research to solve the above-mentioned problems. As a result, they have found that the above-mentioned problems can be solved by using a resin composition for tip seals that contains a polyether ether ketone resin and an inorganic filler having predetermined properties, each in a specific range, and further contains a solid lubricant and carbon fiber, and by injection molding this resin composition. The gist of the present invention is as follows.

[0010] The first aspect of the present invention relates to a resin composition for chip seals, which comprises 70 to 90% by weight of polyether ether ketone resin, 2 to 20% by weight of an inorganic filler having a Mohs hardness of 4 or more and a thermal conductivity of 60 [W / m K] or less, and the remainder being a solid lubricant and carbon fiber.

[0011] In an embodiment of the present invention, the inorganic filler may have a Mohs hardness of less than 7.

[0012] In an embodiment of the present invention, the inorganic filler may be at least one selected from glass spheres and magnesium oxide.

[0013] In an embodiment of the present invention, the solid lubricant may be at least one selected from a fluororesin and a silicone resin.

[0014] In an embodiment of the present invention, the solid lubricant may be contained in an amount of 3 to 10% by weight, and the carbon fiber may be contained in an amount of 5 to 20% by weight.

[0015] In an embodiment of the present invention, the resin composition for a tip seal may have a melt viscosity of 100 to 250 [Pa·s] at a temperature of 400° C. and a shear rate of 1000 [1 / sec].

[0016] In an embodiment of the present invention, the resin composition for a chip seal may have a thermal conductivity of 0.30 to 0.45 [W / m·K].

[0017] The embodiments of the present invention may have any combination of the configurations of the above-described embodiments.

[0018] The second aspect of the present invention relates to a tip seal for a scroll-type refrigerant compressor, which is an injection-molded product of the resin composition for tip seals according to the first aspect of the present invention.

[0019] In an embodiment of the present invention, the injection-molded article has a length direction along the end face of the partition wall of the scroll member of the scroll-type refrigerant compressor and a cross-sectional direction perpendicular to the length direction, and has a cross-sectional area of ​​2.5 mm 2 Hereinafter, the length may be 120 mm or more.

[0020] In the embodiments of the present invention, the resin composition for a chip seal according to the first aspect of the present invention can use the constitutions of the respective embodiments alone or in any combination. [Effects of the Invention]

[0021] According to the present invention, it is possible to provide a resin composition for tip seals that can form injection-molded articles having good heat resistance and abrasion resistance even when the rotational speed of the scroll member is higher than conventional ones, and that can provide good moldability by injection molding of thin-walled, long tip seals, as well as a tip seal for a scroll-type refrigerant compressor that is an injection-molded article of the resin composition for tip seals. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 2 is a partially exploded perspective view of a scroll-type refrigerant compressor. [Figure 2] FIG. 2 is a cross-sectional view of the fixed scroll member and the movable scroll member assembled together. [Figure 3] FIG. [Figure 4] FIG. 4 is a partially enlarged cross-sectional view showing a state in which a tip seal is attached to a scroll member. DETAILED DESCRIPTION OF THE INVENTION

[0023] (Resin composition for chip seal) A resin composition for chip seals (hereinafter sometimes referred to as "resin composition") according to an embodiment of the present invention contains 70 to 90 wt % of polyether ether ketone (hereinafter sometimes referred to as "PEEK") resin, 2 to 20 wt % of an inorganic filler (hereinafter sometimes referred to as "inorganic filler") having a Mohs hardness of 4 or more and a thermal conductivity of 60 [W / m·K] or less, and the remainder being a solid lubricant and carbon fiber.

[0024] Using PEEK resin as a base material allows tip seals for scroll-type refrigerant compressors (hereinafter sometimes referred to as "tip seals") to have better heat resistance than, for example, conventional PPS-based resin compositions, even under harsh conditions such as rotating scroll members at higher speeds than conventional ones. Furthermore, the PEEK resin's properties allow the tip seal to have good chemical resistance. Furthermore, by combining a specific inorganic filler, solid lubricant, and carbon fiber with the base material, (1) even when using PEEK resin, which is generally known to have poor moldability, the specific inorganic filler can suppress the decrease in fluidity of the resin composition during injection molding due to the high thermal conductivity of the carbon fiber, which functions as a reinforcing material, thereby ensuring moldability through injection molding suitable for mass production; and (2) even when the bottom surface of the scroll member, which serves as the sliding surface of the tip seal, has a relatively rough surface, the specific inorganic filler can polish it to a certain extent to reduce the surface roughness, and the solid lubricant can provide lubricity to the sliding surface, thereby ensuring the wear resistance of the tip seal even under harsher conditions such as high-speed rotation.

[0025] Each component of the resin composition will be described below.

[0026] PEEK resin generally has a melting point of 343°C, allowing for continuous use in heated water at 200 to 300°C. Its high heat resistance means it is resistant to melting even during high-speed rotation of scroll members. It also has excellent chemical resistance. That is, it is durable against the various refrigerants and lubricants used in scroll-type refrigerant compressors. Therefore, it is suitable as a base resin for scroll members that can rotate at higher speeds than conventional scroll members while in contact with refrigerants and lubricants. There are no particular limitations on the PEEK resin, as long as it has such heat resistance and chemical resistance and a melt viscosity sufficient to ensure fluidity during injection molding. Such a melt viscosity is preferably 70 to 200 [Pa·s] at a resin temperature of 400°C and a shear rate of 1000 [1 / sec].

[0027] The content of PEEK resin in the resin composition is 70 to 90% by weight. If it is less than 70% by weight, i.e., if the total amount of other components including inorganic filler, solid lubricant, and carbon fiber exceeds 30% by weight, thin-wall formability tends to decrease. If it is more than 90% by weight, i.e., if the total amount of the above-mentioned other components is less than 10% by weight, thin-wall formability is good, but sufficient wear properties tend to be insufficient.

[0028] The inorganic filler has a Mohs hardness of 4 or greater and a thermal conductivity of 60 [W / m·K] or less. As mentioned above, a Mohs hardness of 4 or greater reduces the surface roughness of the mating surface that contacts the sliding surface of the tip seal through a polishing effect, smoothing the surface and ensuring the wear resistance of the tip seal even during high-speed rotation. Furthermore, a Mohs hardness of less than 7.0 is preferable from the viewpoint of preventing excessive polishing of the mating surface that contacts the sliding surface. Furthermore, the lower the thermal conductivity, the better, as this suppresses the effects of the high thermal conductivity of carbon fiber and suppresses a decrease in fluidity due to a decrease in the temperature of the resin composition in the mold during injection molding, thereby ensuring moldability, and therefore there is no particular lower limit.

[0029] Examples of inorganic fillers with a Mohs hardness of 4 or more and a thermal conductivity of 60 [W / m·K] or less include glass spheres (Mohs hardness 4 to 6.5, thermal conductivity 0.55 to 1.1 W / m·K), magnesium oxide (Mohs hardness 4 to 6, thermal conductivity 42 to 60 W / m·K), barium titanate (Mohs hardness 4, thermal conductivity 1.4 W / m·K), and alumina (Mohs hardness 8 to 9, thermal conductivity 20 to 30 W / m·K). These inorganic fillers may be used alone or in combination of two or more. Among these inorganic fillers, at least one selected from glass spheres and magnesium oxide is preferred, with glass spheres being particularly preferred due to their low thermal conductivity.

[0030] The Mohs hardness can be determined by rubbing a material against 10 different standard minerals of different hardness and seeing whether the standard mineral is scratched or not. A commercially available Mohs hardness scale can be used. Thermal conductivity can be measured by the hot wire method, steady heat flow method, laser flash method, etc.

[0031] The content of the inorganic filler in the resin composition is 2 to 20% by weight. If it is less than 2% by weight, the abrasion resistance tends to be insufficient, and if it is more than 20% by weight, the melt viscosity and thermal conductivity tend to be high.

[0032] The solid lubricant can be one that can provide lubrication during sliding of the tip seal. Examples of such solid lubricants include fluororesin, silicone resin, and graphite. Such solid lubricants can be used alone or in combination of two or more. Among these solid lubricants, from the viewpoint of thin-wall formability, those with a thermal conductivity of 60 [W / m·K] or less are preferred, such as fluororesin and silicone resin. For these reasons, the preferred solid lubricant is at least one selected from fluororesin and silicone resin.

[0033] Fluorine resins commonly used as solid lubricants can be used. Examples of such fluororesins include homopolymers or copolymers of fluorine-containing monomers such as tetrafluoroethylene, chlorotrifluoroethylene, vinylidene fluoride, hexafluoropropylene, and perfluoroalkyl vinyl ethers, as well as copolymers of the fluorine-containing monomers with copolymerizable monomers such as ethylene, propylene, and (meth)acrylates. More specifically, examples include polytetrafluoroethylene (PTFE), polychlorotrifluoroethylene, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene copolymers, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymers, ethylene-tetrafluoroethylene copolymers, and ethylene-chlorotrifluoroethylene copolymers. These fluororesins may be used alone or in combination of two or more. When using a mixture of fluororesins, solid lubricants of each fluororesin may be used in combination, or a mixture of fluororesins may be used as the resin component. Among these fluororesins, PTFE is particularly preferred from the viewpoints of frictional properties, wear properties, and heat resistance.

[0034] The PTFE is not particularly limited, and powder obtained by suspension polymerization or emulsion polymerization, or so-called recycled PTFE powder obtained by sintering or electron beam treatment of these, can be used. PTFE obtained by suspension polymerization or emulsion polymerization is prone to fibrillation under slight compressive shear force, which tends to reduce the fluidity of the resin composition, so it is preferable to use recycled PTFE.

[0035] Silicone resins that can be formed into powders can be used. Liquid silicone resins can also be used because bleeding from the resin composition can be suppressed by supporting them on a porous fine particle carrier such as silica. Such silicone resins can include those containing polysiloxanes. Examples of such polysiloxanes include polydimethylsiloxane, polydiphenylsiloxane, polyalkylmethylsiloxane, polydimethylsiloxane-diphenylsiloxane copolymer, alkylmethylsiloxane-arylalkylmethylsiloxane copolymer, poly(3,3,3-trifluoropropylmethylsiloxane), 3,3,3-trifluoropropylmethylsiloxane-dimethylsiloxane copolymer, polymethylsilsesquioxane, and other polyorganosiloxanes (e.g., organosiloxane homopolymers or copolymers), or mixtures thereof. Examples of polysiloxanes include functionalized polysiloxanes. Silicone compositions such as those described in JP 2008-143980 A, as well as copolymers such as dimethylsiloxane-butyl acrylate rubber, polydimethylsiloxane rubber, and dimethylsiloxane-diphenylsiloxane copolymer rubber, can also be used. Furthermore, for the purposes of improving workability and suppressing bleeding from the resin composition, the above-mentioned silicone resins can be supported on porous particulate carriers such as silica (silicon dioxide). Examples of carriers other than silica include carbonates such as calcium carbonate and barium carbonate, silicates such as calcium silicate, barium silicate, and magnesium silicate, phosphates such as calcium phosphate, barium phosphate, magnesium phosphate, zirconium phosphate, and apatite, metal oxides such as alumina, graphite, zeolite, layered clay minerals, polyethylene, polyurethane, cellulose, polyamide, polyvinyl formal, phenolic resin, epoxy resin, and urea resin. Among these, fumed silica, precipitated silica, pulverized silica, and / or calcined silica can be used as the carrier.Examples of commercially available products in which silicone resin is supported on silica include GENIOPLAST (registered trademark) Pellet S manufactured by Asahi Kasei Wacker Silicone Co., Ltd. and TREFIL F-202 manufactured by Toray Dow Corning Co., Ltd.

[0036] The form of the solid lubricant is not particularly limited, and may be in the form of powder, granules, etc., but from the viewpoint of imparting uniform properties, the powder form is preferred.

[0037] The content of the solid lubricant in the resin composition is preferably 3 to 10% by weight from the viewpoint of effectively imparting lubricity, with the total amount of the solid lubricant, carbon fiber, and optional components being the remainder of the PEEK resin and inorganic filler.

[0038] Carbon fiber functions as a fibrous reinforcing material for the tip seal. It is also less aggressive to the bottom surface of the scroll member, and can reinforce the tip seal while maintaining the airtightness of the compression chamber. Any type of carbon fiber that is generally usable as a reinforcing material, such as pitch-based or PAN-based, can be used. PAN-based fibers are preferred from the viewpoint of reinforcing effect. The size of the carbon fiber preferably has an aspect ratio of 100 to 1000 from the viewpoints of its effectiveness as a reinforcing material and thermal conductivity.

[0039] The content of the carbon fiber in the resin composition is preferably 5 to 20% by weight from the viewpoint of functioning as a reinforcing material and ensuring moldability during injection molding, with the total of the solid lubricant and optional components being the remainder of the PEEK resin and inorganic filler.

[0040] In addition to the components described above, other components (optional components) can be added to the resin composition as needed to the extent that they do not affect moldability during injection molding, but it is preferable that the remainder of the PEEK resin and inorganic filler is a solid lubricant and carbon fiber, and that no other components are included.

[0041] The resin composition can be obtained by mixing and kneading the aforementioned components in a predetermined ratio. Conventional kneading methods can be used. For example, the components are dry-mixed using a Henschel mixer or the like, and then melt-kneaded using a twin-screw kneading extruder to obtain the resin composition in the form of molding pellets.

[0042] From the viewpoint of moldability during injection molding, the resin composition thus obtained preferably has a melt viscosity of 100 to 250 [Pa·s] at a temperature of 400°C and a shear rate of 1000 [1 / sec]. Furthermore, from the viewpoint of suppressing temperature drop in the mold during injection molding and ensuring fluidity, the resin composition preferably has a thermal conductivity of 0.30 to 0.45 [W / m·K]. These properties can be achieved by adjusting the composition of each component described above. The melt viscosity can be measured, for example, using the molding pellets described above. It can also be measured using various resin compositions other than molding pellets. There is no substantial difference between these measured values. The thermal conductivity can be measured using an injection-molded product of the resin composition described below. Furthermore, when measured using the thermal conductivity measurement method for injection-molded products described below, there is no substantial difference between the measured values ​​of the resin composition and the injection-molded product. The melt viscosity and thermal conductivity can be measured, for example, using the methods described below.

[0043] (Chip seal for scroll type refrigerant compressor) A tip seal for a scroll refrigerant compressor according to an embodiment of the present invention is an injection-molded product obtained by injection molding the resin composition described above, such as the molding pellets described above. The tip seal has a structure corresponding to the shape of the end face of the scroll member of the scroll refrigerant compressor. For example, in the case of a scroll refrigerant compressor having a structure such as that shown in FIGS. 1 and 2, the tip seal can be a thin-walled, elongated spiral shape as shown in FIG. 3. FIG. 3 shows a tip seal 4 applied to a movable scroll member 2, but the tip seal 3 applied to a fixed scroll member 1, as shown in FIG. 1, also has a similar thin-walled spiral shape. As shown in FIG. 4, this spiral-shaped tip seal 4 is installed in a groove 7 formed in the end face of the spiral-shaped partition wall 6 of the scroll member 2 so that the tip seal 4 protrudes slightly. While FIG. 4 shows the movable scroll member 2 and the tip seal 4 applied thereto, the fixed scroll member 1 and the tip seal 3 applied thereto also have a similar configuration as shown in FIG. 1.

[0044] Thus, the tip seal has a long structure formed continuously along the end face of the partition wall of the scroll member. If the direction along the end face of this partition wall is defined as the length direction, the length of the tip seal can be determined according to the size of the scroll member. Furthermore, the cross-sectional area in the cross-sectional direction perpendicular to the length direction can be determined taking into consideration the need to maintain the hermeticity of the compression chamber, etc., but the tip seal has a thin-walled structure with a significantly smaller thickness than the length direction. The length and cross-sectional area of ​​the tip seal can be determined taking these points into consideration, but a cross-sectional area of ​​2.5 mm 2 Hereinafter, when the length is 120 mm or more, it is preferable in that the significance of injection molding using the above-mentioned resin composition can be enjoyed.

[0045] A tip seal can be obtained as an injection-molded product by using a mold having a cavity corresponding to the shape shown in FIG. 3, melting the resin composition using an injection molding machine, injecting the molten resin composition into the cavity, and then cooling it in the mold to fill the entire cavity. The mold is then demolded at a predetermined temperature. When filling the cavity with the molten resin composition, it is preferable to provide one gate at a position corresponding to one end of the tip seal. Providing multiple gates can result in welds, which can lead to problems such as (a) reduced strength at the weld, (b) undulations in the tip seal's length, which can prevent flatness in a spiral shape and reduce hermeticity, and (c) reduced ease of fitting the tip seal into a groove formed on the end face of a scroll member. Therefore, tip seals without welds are preferred. When molding a thin-walled, long spiral-shaped tip seal with a small cross-sectional area, as shown in FIGS. 1 and 3, the gate may be provided at either the outer end or the inner end of the spiral shape. In this way, even when a gate is provided at one end of the tip seal, the temperature of the resin composition described above is suppressed from decreasing in the mold and its fluidity is maintained, so that even when the molten resin composition is filled from a gate provided at a position corresponding to one end of the tip seal, it is filled throughout the entire thin-walled, long cavity with a small cross-sectional area extending to the other end, resulting in an injection-molded tip seal without welds. Furthermore, the obtained tip seal contains each component in the same content as the formulation of the resin composition described above, and has good wear resistance, heat resistance, and chemical resistance even when the scroll member rotates at higher speeds than conventional ones.

[0046] The tip seal described above can be applied to various scroll-type refrigerant compressors, but is particularly suitable for electrically driven scroll-type compressors in which the scroll member rotates at higher speeds than conventional compressors. Furthermore, such electrically driven scroll-type refrigerant compressors are suitable for use in vehicles, particularly electric vehicles. [Example]

[0047] Hereinafter, embodiments of the tip seal according to the present invention will be described based on examples.

[0048] (Examples 1 to 7, Comparative Examples 1 to 7) The components were mixed in the ratios shown in Table 1 using a Henschel mixer according to a standard method, then melt-kneaded in a twin-screw extruder, passed through a die with a diameter of 2.5 mm to form strands, cooled with water, and then cut into pellets for molding using a strand cutter to obtain a resin composition. Each of the resulting pellets for molding was injection-molded using an in-line injection molding machine to obtain injection-molded products (test specimens) for evaluation, which will be described later.

[0049] The components used in the examples and comparative examples are as follows. (1)PEEK resin Victrex PEEK90P, melt viscosity 90 Pa·s (resin temperature 400°C, shear rate 1000 [1 / sec]) (2) Inorganic fillers Glass balls Potters-Parotini, GB301SA, Mohs hardness 4.0-6.5, thermal conductivity 1.0W / m·K, Magnesium oxide Kyowa Chemical Industry Co., Ltd., Kyowa Mag 30, Mohs hardness 4.0-6.0, thermal conductivity 40-60 W / m·K, ·talc Nippon Talc Co., Ltd. MS-P, Mohs hardness 1.0, thermal conductivity 5-10W / m·K, (3) Solid lubricants ·PTFE resin Kitamura Co., Ltd., KT-600M, thermal conductivity 0.25W / m·K, Silicone resin Genioplast pellet S, manufactured by Asahi Kasei Wacker Silicone Co., Ltd., thermal conductivity 0.25 W / m·K, ·graphite Chuetsu Graphite Industries Co., Ltd., CPB100, thermal conductivity 70W / m·K or more, (4) Fibrous reinforcing material Carbon fiber Teijin Ltd., HT-C217-6MM, Glass fiber Owens Corning Japan, 03MA409C

[0050] (evaluation) <Melt viscosity> The melt viscosity of the molding pellets prepared in Examples 1 to 7 and Comparative Examples 1 to 7 was measured using a capillary rheometer (RHEOGRAPH 20, manufactured by Rheo Labo) at a temperature of 400°C and a shear rate of 1000 [1 / sec].

[0051] <Thermal conductivity> For flat plate-shaped samples (fan gate, width 50 mm, thickness 3.5 mm, flow length 120 mm) injection molded from the molding pellets prepared in Examples 1 to 7 and Comparative Examples 1 to 7, the thermal conductivity was measured in thin film mode using a rapid thermal conductivity meter (QTM-500, manufactured by Kyoto Electronics Manufacturing Co., Ltd.) under the condition that the heat ray and the flow direction were parallel.

[0052] <Thin wall formability> The molding pellets prepared in Examples 1 to 7 and Comparative Examples 1 to 7 were used in an injection molding die having a spiral-shaped cavity (cross-sectional area: 2.04 mm 2 When injection molding was performed under reasonable standard conditions of a barrel temperature of 400°C and a mold temperature of 200°C for a sample (width 1.7mm, thickness 1.2mm, length 120mm), the injection filling peak pressure was evaluated on a two-point scale: "Good" if it was 100 to 250 MPa, and "Poor" if it consistently exceeded 250 MPa.

[0053] <Sliding performance with aluminum alloys> Using the molding pellets prepared in Examples 1 to 7 and Comparative Examples 2 to 5, injection-molded specimens (test specimens) with the sizes and shapes shown in Table 2 were obtained according to a standard method. Using the obtained test specimens, friction and wear tests were conducted using a thrust friction and wear tester (Takachiho Seiki, IIIT-2000N-5000N) under the test conditions shown in Table 2, and the wear height and average friction coefficient were measured. Furthermore, after the test, the test specimens were evaluated for wear resistance and aggressiveness toward the mating material, i.e., mating aggressiveness. Wear resistance was evaluated on a two-point scale: "Good" if the loss in height of the test specimen after 50 hours of testing was 0 to 30 μm, and "Poor" if it exceeded 30 μm. Mating aggressiveness was evaluated on a two-point scale: "Good" if the damage depth at the sliding portion of the aluminum alloy mating sliding member after 50 hours of testing was 0 to 30 μm, and "Poor" if it exceeded 30 μm. Note that Comparative Examples 1, 6, and 7 were not tested due to the difficulty of thin-wall moldability. In Comparative Examples 2, 3, and 4, the wear resistance or attack on the mating member was high when the mating member had a relatively low surface roughness and no surface treatment, so evaluation of the anodized aluminum treatment was not performed.

[0054] The evaluation results are shown in Table 1.

[0055] [Table 1]

[0056] [Table 2]

[0057] As shown in Table 1, by using a resin composition with a specified component composition, good moldability is achieved even for thin-walled, long shapes, and the injection-molded articles obtained using this resin composition have good wear resistance and are suitable as tip seals to be installed in scroll members that rotate at high speeds. [Explanation of symbols]

[0058] 1 Fixed scroll member 2. Movable scroll member 3, 4 Chip seal 5, 6 next door 7 ditch 8, 9 Bottom

Claims

1. A resin composition for chip seals comprising 70 to 90% by weight of polyether ether ketone resin, 2 to 20% by weight of glass spheres having a Mohs hardness of 4 or more but less than 7 and a thermal conductivity of 30 [W / m K] or less, and the remainder being a solid lubricant and carbon fiber.

2. 2. The resin composition for a chip seal according to claim 1, wherein the solid lubricant is at least one selected from the group consisting of fluororesins and silicone resins.

3. 3. The resin composition for chip seals according to claim 1, comprising 3 to 10% by weight of the solid lubricant and 5 to 20% by weight of carbon fiber.

4. The resin composition for chip seal according to claim 1 or 2, wherein the melt viscosity of the resin composition for chip seal at a temperature of 400 ° C. and a shear rate of 1000 [1 / sec] is 100 to 250 [Pa s].

5. The resin composition for a chip seal according to claim 1 or 2, wherein the thermal conductivity of the resin composition for a chip seal is 0.30 to 0.45 [W / m·K].

6. A tip seal for a scroll-type refrigerant compressor, which is an injection-molded product of the resin composition for tip seals according to claim 1 or 2.

7. The injection-molded article has a length direction along the end face of the partition wall of the scroll member of the scroll-type refrigerant compressor and a cross-sectional direction perpendicular to the length direction, and has a cross-sectional area of ​​2.5 mm ２ 7. The tip seal for a scroll-type refrigerant compressor according to claim 6, having a length of 120 mm or more.

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