JP3044492B2 - Rotation mechanism parts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotating mechanism component comprising a thermotropic liquid crystal polymer and spherical glassy carbon.

[0002]

2. Description of the Related Art In recent years, synthetic resin products have been widely used as mechanical parts in order to reduce the weight of the machine and reduce the product cost, and synthetic resin products are often used as rotating mechanism parts which require slidability. Have been. Conventionally, these rotary mechanism parts include, as a resin composition having good slidability, resins such as polyamide, polyacetal, polyphenylene sulfide, and polytetrafluoroethylene, and improve the sliding properties of solid lubricants and lubricating oils. To which additives have been added. These can be used without any problems at relatively low loads and low speeds.However, they are more likely to wear as the load increases and the speed increases.
It becomes unusable due to melting. For this purpose, glass fiber, carbon fiber, various whiskers, etc. are added for the purpose of improving abrasion resistance and heat resistance.These fillers are used to wear metal and resin of mating materials used for sliding parts. There is a problem that it is.

[0003] On the other hand, as is often the case in OA equipment and the like, there is a problem that the temperature inside the machine rises remarkably due to the high density of parts due to the compactness of the machine or the improvement of the processing capability of the machine. Under a very high temperature, a sliding material mainly composed of a so-called general-purpose engineering plastic such as polyamide and polyacetal did not have heat resistance and was deformed and could not withstand the use conditions. Further, in plastics having a large linear expansion coefficient, even if deformation at high temperatures is suppressed, dimensional changes occur due to the large linear expansion coefficient, and precision required for precision parts may not be satisfied.

[0004] In other words, the sliding characteristics required for bearings used under high load, high speed, or high temperature are different from those of conventional bearings in terms of wear resistance, heat resistance, and other physical properties rather than the coefficient of friction. Therefore, the material must be selected from a completely different viewpoint from the conventional sliding member.

On the other hand, a thermotropic liquid crystal polymer has excellent mechanical properties, heat stability, chemical resistance, and ease of molding, has a small molding shrinkage, can be processed precisely, has a small linear expansion coefficient, and has a small coefficient of linear expansion. It is a new material with functions such as small dimensional change, and it should be taken into account that it has high heat resistance among many plastics. Therefore, seizure or melting due to frictional heat is less.

[0006] However, the thermotropic liquid crystal polymer itself has a drawback that it does not have abrasion resistance and has a low limit PV value, and thus is not suitable as a raw material for producing a rotating mechanism part.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art. In particular, the present invention is excellent in abrasion resistance, has a high limit PV value, and damages a mating material. Another object of the present invention is to provide an excellent rotating mechanism component having heat resistance, a low coefficient of linear expansion, and a low molding shrinkage, which are characteristics of the thermotropic liquid crystal polymer.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a thermotropic liquid crystal polymer (a) 90 to 50% by weight, and a spherical glassy carbon (b) 10 characterized by having a particle-like cross section having a glassy luster. A rotating mechanism component comprising about 50% by weight.

The details will be described below.

First, the rotating mechanism parts referred to in the present invention are parts constituting a machine having a rotating mechanism mechanically, and include a holder (B) for holding at least the rotating body (A),
A component having either a rotating shaft (C) that rotates in connection with the rotating body (A) or a bearing portion (D) that receives the rotating shaft (C). Rotating body (A), holder (B),
Both the rotating shaft (C) and the bearing portion (D) are in contact with each other, for example, the rotating body (A) / the holder (B), and the rotating shaft (C) / the bearing portion (D) are in contact with each other when the rotating mechanism component operates. Is what you do. These components constituting the machine having the rotating mechanism may include one or more of the holder (B), the rotating shaft (C), and the bearing portion (D) simultaneously or separately.

In the present invention, the holder (B) for holding the rotating body (A) may be formed integrally with the rotating body. Including the rotating body (A) integrated with the holding shaft (B), the rotating body (A) includes any rotating body that mechanically rotates a mechanical part regardless of its shape, For example, gears, bearings, cams, various motor rotors, screws, cylindrical rollers, rotors and the like can be mentioned. The holder (B) includes a retainer for the shaft.

A specific example of a rotating mechanism component according to the present invention will be described with reference to FIG. FIG. 1 is a schematic diagram of a rotation mechanism using a rotation mechanism component according to the present invention. That is, FIG.
Is a rotating body (A), gears 4, 4 ′ and 4 ″, a holder (B), a shaft 8 integrally formed with the rotating mechanism component 2, and a rotating shaft (C) of 5. And 6, a rotating mechanism parts 2 and 3 having bearings 7, 7 'and 7 "as a bearing part (D), a motor 9, and a case 1 capable of storing the motor 9.

First, when the motor 9 rotates, the torque of the motor is transmitted to the gear 4 attached to the rotating shaft 5. Here, the bearing 7 of the rotating mechanism component 2 is in contact with the rotating shaft 5 of the motor 9 and serves as a bearing of the rotating shaft 5. The torque transmitted to the gear 4 is further transmitted to the rotating shaft 6 via a gear 4 ′, which is a rotating body held by the shaft portion 8, and a gear 4 ″ attached to the rotating shaft 6.
The rotating shaft 6 is supported by bearings 7 and 7 'of the rotating mechanism parts 2 and 3. In this embodiment, the rotating mechanism parts 2 and 3 are made of the composition according to the present invention. In the example of FIG. 1, the gears 4, 4 ', 4 "and the rotating shaft 5,
6 are each made of metal and are not made by the composition of the present invention, but at least a part of them can be made by the composition according to the present invention if desired. In this case, for example, the rotating shaft 6 and the gear 4 may be integrally formed.

The thermotropic liquid crystal polymer referred to in the present invention is a thermoplastic meltable polymer exhibiting optical anisotropy when melted. Such a polymer exhibiting optical anisotropy at the time of melting has a property that polymer molecular chains take a regular parallel arrangement in a molten state. The properties of the optically anisotropic molten phase can be confirmed by a normal polarization inspection method using an orthogonal polarizer.

For example, liquid crystalline polyester, liquid crystalline polycarbonate, liquid crystalline polyesterimide and the like can be mentioned. Specifically, (whole) aromatic polyester, polyester amide, polyamide imide, polyester carbonate, polyazomethine and the like are used.

[0016] Thermotropic liquid crystal polymers are generally made from monomers that are elongated, flat, rigid and have a plurality of chain-extended bonds in either a coaxial or parallel relationship along the long chain of the molecule. Is done.

The thermotropic liquid crystal polymer used in the present invention can be produced from the above compound by various ester forming methods such as a melt acidification method and a slurry polymerization method. In the thermotropic liquid crystal polymer used in the present invention, a thermoplastic resin in which a part of one polymer chain is composed of a polymer segment forming an anisotropic molten phase and the remaining part does not form an anisotropic molten phase And a polymer composed of the following segments. Further, a composite of a plurality of thermotropic liquid crystal polymers is also included.

As the polymer forming the optically anisotropic molten phase as described above, for example, a wholly aromatic polyester,
Examples thereof include wholly aromatic polyester amides, and the constituent components thereof include (A) at least one kind of aromatic dicarboxylic acid, (B) at least one kind of aromatic hydroxycarboxylic acid compound, and (C) aromatic diol compound. (D) (D1) aromatic dithiol, (D2) aromatic thiophenol, (D3) at least one aromatic thiol carboxylic acid compound, (E) aromatic hydroxyamine, aromatic diamine compound At least one of the above. Although these may be constituted independently, in many cases (A), (C) and (A)
And (D), (A) (B) and (C), (A) (B) and (E), or (A) (B) (C) and (E). .

The aromatic dicarboxylic acid compound (A) includes terephthalic acid, 4,4'-diphenyldicarboxylic acid, 4,4'-triphenyldicarboxylic acid, 2,6-
Naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, diphenylether-4,4'-dicarboxylic acid, diphenoxyethane-4,4'-dicarboxylic acid, diphenoxybutane-4,
4'-dicarboxylic acid, diphenylethane-4,4'-dicarboxylic acid, isophthalic acid, diphenyl ether-3,
3'-dicarboxylic acid, diphenoxyethane-3,3'-
Aromatic dicarboxylic acids such as dicarboxylic acid, diphenylethane-3,3′-dicarboxylic acid, 1,6-naphthalenedicarboxylic acid or chloroterephthalic acid, dichloroterephthalic acid, bromoterephthalic acid, methylterephthalic acid,
Alkyl, alkoxy or halogen-substituted aromatic dicarboxylic acids such as dimethyl terephthalic acid, ethyl terephthalic acid, methoxy terephthalic acid, ethoxy terephthalic acid and the like.

(B) Examples of the aromatic hydroxycarboxylic acid compound include aromatic hydroxycarboxylic acids such as 4-hydroxybenzoic acid, 3-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid and 6-hydroxy-1-naphthoic acid. Carboxylic acid or 3-methyl-4-hydroxybenzoic acid, 3,5
-Dimethyl-4-hydroxybenzoic acid, 2,6-dimethyl-4-hydroxybenzoic acid, 3-methoxy-4-hydroxybenzoic acid, 3,5-dimethoxy-4-hydroxybenzoic acid, 6, hydroxy-5-methyl -2-naphthoic acid, 6-hydroxy-5-methoxy-2-naphthoic acid,
2-chloro-4-hydroxybenzoic acid, 3-chloro-4
-Hydroxybenzoic acid, 2,3-dichloro-4-hydroxybenzoic acid, 3,5-dichloro-4-hydroxybenzoic acid, 2,5-dichloro-4-hydroxybenzoic acid, 3
-Bromo-4-hydroxybenzoic acid, 6-hydroxy-5
Alkyl, alkoxy or halogen-substituted aromatic hydroxycarboxylic acids such as -chloro-2-naphthoic acid, 6-hydroxy-7-chloro-2-naphthoic acid and 6-hydroxy-5,7-dichloro-2-naphthoic acid Is mentioned.

(C) As the aromatic diol, 4,4 ′
-Dihydroxydiphenyl, 3,3'-dihydroxydiphenyl, 4,4'-dihydroxytriphenyl, hydroquinone, resorcinol, 2,6-naphthalenediol, 4,4'-dihydroxydiphenylether, bis (4-hydroxyphenoxy) ethane, Aromatic diols such as 2,3'-dihydroxydiphenyl ether, 1,6-naphthalenediol, 2,2'-bis (4-hydroxyphenyl) propane, bis (4-hydroxyphenyl) methane or chlorohydroquinone, methylhydroquinone, t- Alkyl, alkoxy or halogen-substituted aromatic diols such as butylhydroquinone, phenylhydroquinone, methoxyhydroquinone, phenoxyhydroquinone, 4-chlororesorcin, 4-methylresorcin and the like.

(D1) Examples of the aromatic dithiol include benzene-1,4-dithiol, benzene-1,3-dithiol, 2,5-naphthalene-dithiol, and 2,7-naphthalene-dithiol.

(D2) As the aromatic thiophenol,
4-mercaptophenol, 3-mercaptophenol, 6-mercaptophenol and the like.

(D3) Examples of the aromatic thiol carboxylic acid include 4-mercaptobenzoic acid, 3-mercaptobenzoic acid, 6-mercapto-2-naphthoic acid, and 7-mercapto-2-naphthoic acid.

(E) As aromatic hydroxyamine and aromatic diamine compounds, 4-aminophenol, N-
Methyl-4-aminophenol, 1,4-phenylenediamine, N-methyl-1,4-phenylenediamine,
N, N'-dimethyl-1,4-phenylenediamine, 3
-Aminophenol, 3-methyl-4-aminophenol, 2-chloro-4-aminophenol, 4-amino-
1-naphthol, 4-amino-4'-hydroxydiphenyl, 4-amino-4'-hydroxydiphenyl ether, 4-amino-4'-hydroxydiphenylmethane,
4-amino-4'-hydroxydiphenyl sulfide,
4,4'-diaminophenyl sulfide (thiodianiline), 4,4'-diaminodiphenyl sulfone, 2,5
-Diaminotoluene, 4,4'-ethylenedianiline,
4,4′-diaminodiphenoxyethane, 4,4′-diaminodiphenylmethane (methylenedianiline),
4'-diaminodiphenyl ether (oxydianiline) and the like.

Particularly preferred in the present invention is at least a compound represented by the general formula:

Embedded image

(Co) polymer containing a monomer unit represented by the following formula: Specific examples of these are as follows.

Embedded image

That is, a particularly preferred wholly aromatic polyester of the present invention is a polyester having a repeating unit derived from each of three compounds of p-hydroxybenzoic acid, phthalic acid and biphenol, or p-hydroxybenzoic acid and hydroxy. It is a polyester having a repeating unit derived from each of two compounds of naphthoic acid.

The glassy carbon referred to in the present invention has a turbostratic structure with a very small crystal size as its basic structure, and has a non-oriented structure as a fine structure, such as a phenol resin, a furan resin, and an epoxy resin. , Unsaturated polyester resin, urea resin, melamine resin, alkyd resin,
It is manufactured by carbonizing a thermosetting resin such as a xylene resin at a high temperature.

The vitreous carbon is characterized in that its fracture surface has a vitreous luster. In addition, the diffraction angle of the spectrum (2
θ) It is also confirmed by having a broad peak around 23 to 25 degrees. The X-ray diffraction method is based on the usual method,
It is measured by the u-Kα ray (double line). A conventional carbon material such as graphite does not have such a broad peak, but shows a sharp _d002 peak due to crystallinity at another diffraction angle (2θ = 26.4 ° C.). It is preferable that the glassy carbon of the present invention has substantially no peak characteristic of graphite. In addition, a mere organic carbonized material does not have a glassy gloss in its fractured surface, and of course, its X
In the X-ray diffraction spectrum, the glassy carbon does not have a specific diffraction angle peak characteristic of graphite, of course.

Incidentally, this glassy carbon sometimes contains an incompletely carbonized product or an uncarbonized product due to being produced by carbonizing a thermosetting resin such as a phenol resin as described above.

That is, even if it is confirmed that the fracture surface has a glassy gloss or that the X-ray diffraction spectrum has a wide peak at a specific diffraction angle, the glassy carbon is not. It may contain fully or uncarbonized material.

When glassy carbon is blended with a thermoplastic resin, the presence of the incompletely carbonized or uncarbonized material as described above causes a problem in the molding process of the thermoplastic resin or the molded product itself. Often not. That is,
This is because these incompletely carbonized products or uncarbonized products are considered to be the thermosetting resin itself, which is the raw material resin of glassy carbon, or its thermally decomposed low polymer.

On the other hand, the forming temperature of the thermotropic liquid crystal polymer is extremely high because one of its features is a high melting point which can be said to be abnormal among polymers. In such a case, the above-mentioned incomplete carbonized material or uncarbonized material contained in the glassy carbon is decomposed and easily causes gas generation. At high temperatures, especially in molding under high pressure, such as compression or injection molding, the generation of gas, even in trace amounts, can be a fatal defect in the working process or in the molding. For example, in an extreme case, the molding itself is difficult due to gas generation, or blisters and flow marks are observed on the surface of the molded article, and the commercial value of the molded article is lost.

Here, even if the fractured surface is glassy carbon characterized by having a glassy luster, the type of raw material resin, its preparation method, raw material particle shape, carbonization temperature,
Products with different properties are produced depending on the carbonization time, the type of atmospheric gas, the pressure during carbonization, and other conditions. That is, the content and properties of the incompletely carbonized or uncarbonized material in the produced glassy carbon are different.

In the rotary mechanism component of the present invention, in view of the fact that it is blended with the thermotropic liquid crystal polymer having a high melting point as described above, a spherical glass having a weight loss of 5% by weight or less under the conditions specific to the liquid crystal polymer. It is preferred to use carbon.

Here, the weight loss refers to the use of, for example, a thermobalance as a measuring device, and a heating rate of 35 ° C./min.
It is defined as the weight loss when heated to 0 ° C. and held at that temperature for 30 minutes.

Glassy carbon having a weight loss of more than 5% by weight under the above conditions, when combined with a thermotropic liquid crystal polymer having a high melting point, generates gas due to heating during molding, making molding difficult as described above. Or blisters or flow marks on the molded product, resulting in a decrease in productivity and commercial value.

On the other hand, the shape is preferably spherical, and more preferably a shape close to a true sphere. A non-spherical shape such as an irregular shape is not preferable when used for a member requiring slidability, such as the rotating mechanism component of the present invention, because the metal or resin of the mating material is worn away.

The amount of spherical glassy carbon added is 1
It is 0 to 50% by weight, preferably 25 to 40% by weight. In this range, the abrasion resistance and the like are sufficient, and the effects of the present invention can be exhibited.

The addition amount of spherical glassy carbon is 10% by weight.
If the amount is less than 50%, the abrasion resistance is insufficient. Even if the amount exceeds 50% by weight, further improvement of the abrasion resistance cannot be expected. Further, the strength of the obtained molded article is also reduced.

Here, various additives can be added to the thermotropic liquid crystal polymer composition used for the rotating mechanism component of the present invention.

The additives include inorganic fillers, organic fillers, stabilizers, ultraviolet absorbers, pigments, dyes, modifiers and the like. Of these, inorganic fillers are particularly important, and are often used for improving workability, physical properties, and the like.

Examples of inorganic fillers include graphite, molybdenum disulfide, bronze, talc, mica, clay, sericite, calcium carbonate, calcium silicate, calcium phosphate, calcium pyrophosphate, silica, alumina, aluminum hydroxide, calcium hydroxide, and calcium hydroxide. Graphite graphite, potassium titanate, etc., as well as glass fiber, carbon fiber,
Various whiskers can be added as long as the effects of the present invention are not impaired.

Examples of the organic filler include various thermoplastic and thermosetting resins. In particular, a fluororesin represented by polytetrafluoroethylene is preferably used. The method of mixing the thermotropic liquid crystal polymer and the spherical glassy carbon and the above-mentioned additives to be added thereto,
There is no particular limitation, and various means can be applied.
For example, they may be separately supplied to an extruder and melt-mixed, or may be preliminarily mixed by a mixer such as a Henschel mixer or a tumbler and then supplied to the extruder.

In addition, the glassy carbon used in the present invention can be added during the polymerization of the thermotropic liquid crystal polymer. Even in the case of a thermotropic liquid crystal polymer composition in which glassy carbon is blended at the time of polymerization as described above, naturally, when a processed product is produced therefrom, that is, the composition is formed by molding such as injection molding or compression molding. When molding, the thermotropic liquid crystal polymer is melt-molded and exposed to a high temperature. Therefore, even in such a case, the predetermined effect of the present invention is achieved.

Further, the composition obtained in this way is molded into a rotating mechanism part of the present invention by a method such as injection, compression, extrusion or the like. It may be blended and shaped.

In many cases, lubricating oils and the like are used as lubricants for rotating mechanism parts. These are inactive at normal temperature, but exhibit corrosiveness to contact members other than at high temperatures due to frictional heat. Sometimes. However, the resin composition comprising the thermotropic liquid crystal polymer and the spherical glassy carbon in the present invention has sufficient chemical resistance at high temperatures, so even under a high temperature atmosphere when lubricating oil is used for the sliding portion. It is not affected by lubricating oils or other chemicals.

In addition, the rotating mechanism parts used in precision machines are required to have dimensional accuracy of products and dimensional stability against temperature changes due to their properties. The bearing of the present invention is also excellent in this respect. That is, the thermotropic liquid crystal polymer exerts a shear force at the time of melting, whereby the molecular chains are oriented in the shearing direction and exhibit extremely good fluidity. And, since it shows a crystalline state at the time of melt flow, there is very little change in structure and change in specific volume when it is cooled and solidified in a mold. As a result, molding shrinkage is small and precision molding can be easily performed. Further, since the molecules are highly oriented and form a rigid molecular chain, the coefficient of linear expansion is small. Therefore, the processing accuracy can be maintained over a wide temperature range, and there is no malfunction due to a temperature change.

[0050]

The rotating mechanism component according to the present invention has the following features, and is particularly suitable for use under high load, high speed and high temperature. (1) Since a polymer having a particularly high melting point is used among conventional plastics, melting, seizure, and the like due to frictional heat are less likely to occur. (2) Since a thermotropic liquid crystal polymer having a small linear expansion coefficient is used as a material, a processing temperature can be maintained over a wide temperature range. In addition, precision molding is possible because of a small molding shrinkage. (3) At high temperatures due to frictional heat, lubricating oil or the like, which should normally be inert, may show corrosiveness to members in contact therewith. However, the rotating mechanism component of the present invention is also stable against them.

[0051]

EXAMPLES The present invention will be described in more detail with reference to Examples, but these Examples do not limit the scope of the present invention, but show preferred embodiments of the present invention. First, raw materials used in Examples and Comparative Examples are collectively shown.

Thermotropic liquid crystal polymer A: A powder of a thermotropic liquid crystal polymer which is a terpolymer of terephthalic acid, 4-hydroxybenzoic acid and 4,4′-dihydroxydiphenyl. Melting point 42
0 ° C.

B: Powder of a thermotropic liquid crystal polymer which is a quaternary copolymer of terephthalic acid, isophthalic acid, 4-hydroxybenzoic acid and 4,4'-dihydroxydiphenyl. Melting point 350 [deg.] C.

Spherical glassy carbons ad are spherical glassy carbons obtained by firing and carbonizing a thermosetting resin. a: Bellpearl C-800 (trade name) b: Univex GCP-50 (H) (trade name) c: Bellpearl C-2000 (trade name) d: Univex GCP-50 (L) (trade name) Bellpearl …… Kanebo UNIVEX manufactured by Unitika Ltd.

The respective weight loss and average particle size are as follows. a: Weight loss 1.2%, average particle size 10 micrometer b: Weight loss 0.5%, average particle size 30 micrometer c: Weight loss 0.2%, average particle size 10 micrometer or less d: Weight loss 5.1% , Average particle size 30 microns

It has been confirmed that all of these glassy carbons have a glassy luster in the particle fracture surface,
The X-ray diffraction spectrum measured by -Kα ray (double ray) had a distinctly broad peak around a diffraction angle (2θ) of 23 to 25 degrees. In the glassy carbon particles a, b and d, sharp peaks unique to graphite were not substantially observed, but the diffraction angle 2θ was observed for carbon c.
At d = 26.4 degrees, a _d002 peak was observed as a shoulder.

Weight loss: 35 from room temperature at a rate of 10 ° C./min.
Weight loss when the temperature was raised to 0 ° C. and held at this temperature for 30 minutes. (Thermobalance SSC-5020 manufactured by Seiko Instruments Inc.
The measurement was performed by TG / DTA200. )

Graphite ACP (natural graphite, flaky, average particle size, manufactured by Nippon Graphite Co., Ltd.)
10 μm)

Glass fiber Mirdo glass fiber M manufactured by Asahi Fiber Glass Co., Ltd.
FA (trade name) Diameter 10-15 micrometer Length 30-100 micrometer

Examples 1 and 2 The above-mentioned raw materials were blended in the proportions shown in Table 1 and mixed with a Henschel mixer, followed by a twin-screw extruder (manufactured by Ikegai Iron Works:
(PCM-30 type), and the mixture was melt-kneaded (temperature: 420 ° C., screw rotation speed: 200 rpm) and pelletized.

Next, the pellets were obtained using an injection molding machine (Sumitomo Heavy Industries Machinery Co., Ltd .: Nestal SG25 type) at a cylinder temperature of 400 ° C., an injection pressure of 1000 kgf / cm ² and a mold temperature of 150 ° C., with a diameter of 5 cm and a thickness of A 3 mm disk was formed. The obtained test piece was subjected to a Suzuki friction and wear tester under the conditions of a pressure of 5 kgf / cm ² and a speed of 20 m / min.
Using a ring-shaped S45C steel or aluminum having an outer diameter of 25.6 mm and an inner diameter of 20 mm as a mating material, a wear coefficient and a wear amount of the mating material were measured.

Further, using the injection molding machine described above, a bending test piece was molded under the same conditions, and AS
The bending strength was measured according to TM D-790. Also,
Simultaneously, ten test pieces were continuously formed, the formability and the appearance were observed, and the number of blisters and flow marks generated was recorded.

The rotary mechanism parts 2 and 3 shown in FIG. 1 were molded under the same conditions using the above-mentioned injection molding machine. Further, assembling the rotating mechanism parts, the motor is driven at 50 / min.
It was operated at zero rotation, the ambient temperature was raised from room temperature to 150 ° C., and the state of the operation was observed. When the operating condition is good, ○, when the rotation is uneven, and when the shaft is blurred, △,
When a part was damaged, it was evaluated as x.

Examples 3 and 4 The above-mentioned raw materials were blended in the proportions shown in Table 1 and mixed with a Henschel mixer, followed by a twin-screw extruder (Ikegai Iron Works:
(PCM-30 type), and the mixture was melt-kneaded (temperature: 350 ° C., screw rotation speed: 200 rpm) and granulated into pellets.

Next, the pellets were obtained using an injection molding machine (Nestal SG-25 type, manufactured by Sumitomo Heavy Industries, Ltd.) at a cylinder temperature of 340 ° C., an injection pressure of 1000 kgf / cm ² , and a mold temperature of 80 ° C. with a diameter of 5 cm. Then, a disk having a thickness of 3 mm was formed, and the wear characteristics were measured in the same manner as in Example 1.

Further, using the injection molding machine described above, a bending test piece and a rotating mechanism component were molded under the same conditions, and the same evaluation was performed.

In Examples 2 and 4, graphite was added as an inorganic filler. The above results are summarized in Table 1.

Comparative Examples 1, 3 and 5 The above-mentioned raw materials were blended in the proportions shown in Table 2 and
In the same manner as in Example 1, pellet granulation, forming of a disk, bending test piece, and rotating mechanism component were performed and evaluated. The results are shown in Table 2.

Comparative Examples 2, 4 and 6 The above-mentioned various raw materials were blended in the proportions shown in Table 2 and
In the same manner as in Example 1, pellet granulation, forming of a disk, bending test piece, and rotating mechanism component were performed and evaluated. The results are shown in Table 2.

Here, in comparison with Examples 1 to 4 and Comparative Examples 1 to 6, Examples 1 to 4 show that the proportions of the thermotropic liquid crystal polymer and glassy carbon and the glassy carbon at 350 ° C.
Because all of the weight loss in 30 minutes is in the desired range,
All of the abrasion characteristics, moldability, appearance, and characteristics as rotating mechanism parts were excellent.

On the other hand, in Comparative Examples 1 and 2, graphite and glass fiber, which have been used for improving the conventional slidability and abrasion resistance, were used, but the wear coefficient was large. The value of the wear amount of the mating material is also large. In particular, the difference is remarkable in the case of soft aluminum in terms of wear of the mating material. The evaluation as a rotating mechanism part is not good either.

In Comparative Example 3, spherical glassy carbon contained 10
Since the content is less than 10% by weight, the abrasion resistance is insufficient. Further, in Comparative Example 4, the mechanical strength was insufficient because the amount of spherical glassy carbon exceeded 70% by weight. As a result of the evaluation as a rotating mechanism part, the shaft portions were damaged in Comparative Examples 3 and 4.

Further, in Comparative Examples 5 and 6, the weight loss of glassy carbon in air at 350 ° C. for 30 minutes was more than 5% by weight, so that gas generation adversely affected the moldability and the appearance of the molded product. . That is, at the time of injection molding, a phenomenon was observed in which the resin nose dripped while foaming from the nozzle after the resin was measured, and flow marks and blisters were generated in the obtained molded article.

[0074]

[Table 1]

[0075]

[Table 2]

[Brief description of the drawings]

FIG. 1 is a schematic view of a rotation mechanism including a rotation mechanism component according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Case 2, 3 Rotating mechanism parts 4, 4 ', 4 "Gear (rotating body) 5 Rotating shaft 6 Rotating shaft 7, 7', 7" Bearing part 8 Holder 9 Motor

Claims (4)

(57) [Claims] 1. Thermotropic liquid crystal polymer (a) 9
A rotating mechanism component comprising 0 to 50% by weight, and 10 to 50% by weight of a spherical glassy carbon (b) characterized by a particle fracture surface having a glassy luster. 2. The rotating mechanism component according to claim 1, wherein a weight loss of the glassy carbon when held in air at 350 ° C. for 30 minutes is 5% by weight or less. 3. The rotating mechanism component according to claim 1, wherein the thermotropic liquid crystal polymer is a wholly aromatic polyester. 4. The thermotropic liquid crystalline polymer contains at least a monomer unit represented by the following general formula (co)
The rotating mechanism component according to any one of claims 1 to 3, which is a polymer. Embedded image