JPH05107977A - Separation claw for copier - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a separating claw for a copying machine, which is excellent in thermal deformation resistance, thermal shock resistance, and non-attack to a partner roll, and has excellent dimensional accuracy. [Structure] Separation claws for a copying machine, thermotropic liquid crystal polymer (a) 90 to 30% by weight, and spherical glassy carbon (b) 10 to 70% by weight characterized by having a glassy luster on the particle fracture surface. Compose by.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a separating claw for a copying machine, which comprises a thermotropic liquid crystal polymer resin composition.

[0002]

2. Description of the Related Art In a conventional apparatus such as a dry copying machine, an electrostatic latent image formed on the surface of a photosensitive drum corresponding to characters and figures is converted into toner, and then this toner image is fed into a paper feed cassette. The toner image and the paper fiber are fused and transferred to each other, and the toner image and the paper fiber are fused and separated from each other. A mechanism to prevent it is incorporated. In order to reliably discharge the copy paper that has passed through the fixing roller without wrapping around the roller, a method is used in which a separation claw is used and the end of the copy paper is scooped up while the tip of the copy claw is in close contact with the outer peripheral surface of the roller. .. Therefore, in such a separating claw, the frictional resistance against the outer peripheral surface of the roller is small, the surface is not damaged, the mechanical strength is particularly high, and the rigidity is high, and the tip shape is sufficiently accurate. In addition, characteristics such as not adhering the toner are required.

Particularly in recent years, with the increase in copying speed,
In many cases, the heating temperature of the fixing roller is set to a high temperature, and heat resistance of 250 ° C. or higher, particularly 300 ° C. or higher is required for the separating claw.

Among the required characteristics of the separating claw, for improving the non-adhesiveness to the toner, for example, a coating of a fluororesin or a specific low molecular weight fluororesin polymer is formed on the separating claw or the fluororesin is used. The method of kneading non-adhesiveness improver such as the above into the separating nail material is taken,
The high-temperature rigidity, thermal shock resistance, and non-aggressiveness of the mating roll largely depend on the type of heat-resistant resin composition or filler used for the separating nail material. Specific examples of the separating nail material include polyimide, polyamide, polyphenylene sulfide, polyether ketone, polyether sulfone, polyetherimide, polysulfone, and aromatic polyester. Among them, for example, 250 ° C. or higher. In order to function as a separating nail at high temperature, resins such as polyether sulfone, polyether imide and polysulfone have a glass transition point of 2 or less.
Since it is less than 50 ° C. and is amorphous, it softens at a temperature above the glass transition point, and therefore its heat resistance is too low. Further, resins such as polyphenylene sulfide and polyether ketone have a glass transition point of less than 250 ° C. similarly, but since they are crystalline resins, glass fibers, potassium titanate fibers, heat resistant fibers such as carbon fibers, Or, due to the reinforcing effect based on the addition of an inorganic powder filler such as mica or talc to these fibers, the heat resistance is significantly improved, but on the other hand, the problem of damaging the mating roll and the nail tip of these reinforcing agents If the filling is poor, there is a problem of reliability that the heat distortion resistance is significantly reduced. Further, among the polyimide resins, the thermosetting polyimide resin that forms a three-dimensional network is fragile, so it is necessary to reinforce it with a filler like the above-mentioned polyphenylene sulfide resin, and the same problem. Have a point. Further, the polyamide-imide resin has heat resistance of 250 ° C. or higher as a separating nail material without adding a reinforcing agent, but absorbs water (or absorbs moisture).
At times, it has the drawback of lowering the heat resistance, and when absorbing a relatively large amount of water, the heat resistance becomes very poor. Specifically, when a molded product is rapidly heated while absorbing water, the moisture inside the molded product becomes high-pressure steam, causing a dimensional change in the molded product with a certain size or more, and a phenomenon such as swelling or foaming of the surface. It is well known that the minimum temperature (this is called thermal shock temperature) that causes heat is significantly lowered, and what has heat resistance of about 280 ° C at the time of absolute drying is lowered to about 210 ° C by a large amount of water absorption. There's a problem.
In addition, among polyimide resins, there is a polyimide resin made of a polymer having a very large molecular weight called a thermoplastic polyimide, for example, polyimide “Vespel” manufactured by DuPont USA, etc. These are melt-molded such as injection molding. Therefore, it is excellent in heat resistance but not suitable for practical use.

On the other hand, the thermotropic liquid crystal polymer does not cause a phenomenon such as a decrease in thermal shock temperature due to water absorption like polyamide resin does, and exhibits an orientation characteristic of the liquid crystal polymer, which results in exerting self-strengthening property. Since it is possible to improve the heat deformation resistance without a reinforcing material and therefore without damaging the mating roller with the edges of the fibers, etc., it has been tried as a separating claw, but the self-reinforcing property of this orientation If the variation is large and the variation is small, there is a problem that the heat deformation temperature of the separating claw is remarkably lowered.

[0006]

As described above, in the prior art, the separation for a copying machine, which is excellent in heat distortion resistance, thermal shock resistance, non-aggressiveness against a partner roll, and excellent in dimensional accuracy. There was a problem that nails could not be obtained.

[0007]

The present invention is directed to 90 to 30% by weight of thermotropic liquid crystal polymer (a), and spherical glassy carbon (b) 10 characterized by a particle fracture surface having a glassy luster. A separating claw for a copying machine, characterized in that the separating claw comprises 70% by weight.

The details will be described below. The thermotropic liquid crystal polymer referred to in the present invention is a thermoplastic meltable polymer that exhibits optical anisotropy when melted. Such a polymer exhibiting optical anisotropy when melted has the property that the polymer molecular chains take a regular parallel arrangement in the melted state. The properties of the optically anisotropic molten phase can be confirmed by a usual polarization inspection method using a crossed polarizer.

Examples thereof include liquid crystalline polyester, liquid crystalline polycarbonate, liquid crystalline polyesteride and the like. Specifically, (all) aromatic polyesters, polyester amides, polyamide imides, polyester carbonates, polyazomethines, and the like.

Thermotropic liquid crystal polymers are generally elongate, flat, composed of monomers that have multiple chain extension bonds in either rigid or coaxial or parallel relationship along the long chain of the molecule. Manufactured.

The thermotropic liquid crystal polymer used in the present invention can be produced by various ester forming methods such as the melt acidolysis method and the slurry polymerization method.

In the thermotropic liquid crystal polymer used in the present invention, a part of one polymer chain is composed of polymer segments forming an anisotropic melt phase, and the remaining part does not form an anisotropic melt phase. Also included are polymers composed of segments of thermoplastic resin. Further, it also includes a composite of a plurality of thermotropic liquid crystal polymers.

As the polymer which forms the optically anisotropic molten phase as described above, for example, wholly aromatic polyester,
Examples thereof include wholly aromatic polyester amides and the like. As its constituent component, at least one of (A) aromatic dicarboxylic acid is used.
Species, at least one kind of (B) aromatic hydroxycarboxylic acid compound, at least one kind of (C) aromatic diol compound, (D) (D1) aromatic dithiol, (D2) aromatic thiophenol, (D3) ) At least one kind of aromatic thiolcarboxylic acid compound, at least one kind of (E) aromatic hydroxyamine, aromatic diamine compound and the like. Although these may be configured independently, most of them are (A) and (C), (A) and (D), (A) (B) and (C), (A) (B) and ( E) or (A) (B)
(C) and (E) are combined and configured.

The above-mentioned (A) aromatic dicarboxylic acid type compounds include terephthalic acid, 4,4'-diphenyldicarboxylic acid, 4,4'-triphenyldicarboxylic acid, 2,6-
Naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, diphenyl ether-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,
Examples thereof include alkyl, alkoxy or halogen substitution products of the above aromatic dicarboxylic acids such as dimethyl terephthalic acid, ethyl terephthalic acid, methoxy terephthalic acid and ethoxy terephthalic acid.

(B) Aromatic hydroxycarboxylic acid compounds include aromatic hydroxy 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-
Alkyl, alkoxy or halogen substitution of aromatic hydroxycarboxylic acid such as 5-chloro-2-naphthoic acid, 6-hydroxy-7-chloro-2-naphthoic acid, 6-hydroxy-5,7-dichloro-2-naphthoic acid The body.

As the (C) aromatic diol, 4,4 '
-Dihydroxydiphenyl, 3,3'-dihydroxydiphenyl, 4,4'-dihydroxytriphenyl, hydroquinone, resorcin, 2,6-naphthalenediol, 4,4'-dihydroxydiphenyl ether, bis (4-hydroxyphenoxy) ethane, 3 Aromatic diols such as 3,3′-dihydroxydiphenyl ether, 1,6-naphthalene diol, 2,2-bis (4-hydroxyphenyl) propane and bis (4-hydroxyphenyl) methane, or chlorohydroquinone, methylhydroquinone, t-butyl Examples thereof include alkyl-, alkoxy- or halogen-substituted aromatic diols such as hydroquinone, phenylhydroquinone, methoxyhydroquinone, phenoxyhydroquinone, 4-chlororesorcin, and 4-methylresorcin.

Examples of the aromatic dithiol (D1) include benzene-1,4-dithiol, benzene-1,3-dithiol, 2,6-naphthalene-dithiol and 2,7-naphthalene-diol.

Examples of the aromatic thiophenol (D2) include
4-mercaptophenol, 3-mercaptophenol, 6-mercaptophenol and the like can be mentioned.

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

Examples of (E) aromatic hydroxyamine and aromatic diamine compounds include 4-aminophenol-methyl-4-aminophenol, 1,4-phenylenediamine, N-methyl-1,4-phenylenediamine and 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,
4'-diamino diphenyl ether (oxydianiline) etc. are mentioned.

Particularly preferred in the present invention is at least the general formula

[Chemical 2] Is a (co) polymer containing a monomer unit represented by: Specific examples of these are as follows.

[0022]

[Chemical 3]

That is, a particularly preferred wholly aromatic polyester of the present invention is a polyester having repeating units 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 repeating units respectively derived from two compounds of naphthoic acid.

The glassy carbon referred to in the present invention has a disordered structure having an extremely small crystal size as a basic structure and has a non-oriented structure as a fine structure. Phenolic resin, furan resin, epoxy resin , Unsaturated polyester resin, urea resin, melamine resin, alkyd resin,
It is obtained by carbonizing a thermosetting resin such as a xylene resin at a high temperature.

This glassy carbon is characterized in that its fracture surface has a glassy luster, but in addition to this, the diffraction angle (2) of the spectrum in the usual X-ray diffraction method is used.
It is also confirmed by having a broad peak around θ) of 23 to 25 degrees. The X-ray diffraction method is a conventional method, and C
It is measured by u-Kα ray (double line).

Conventional carbon materials such as graphite do not have such a broad peak and show a sharp d ₀₀₂ peak due to crystallinity at other diffraction angles (2θ = 26.4 ° C.).

The glassy carbon of the present invention is preferably one which does not substantially have the peak characteristic of graphite. Further, a mere organic carbonized product does not have a glassy luster in its fracture surface, and of course does not have the peak of the specific diffraction angle characteristic of graphite as well as the above glassy carbon in its X-ray diffraction spectrum.

By the way, this glassy carbon may contain an incomplete 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 the glassy carbon is confirmed by the fact that the fracture surface has a glassy luster or has a wide peak at a specific diffraction angle in the X-ray diffraction spectrum, the glassy carbon is not It may include completely carbonized or uncarbonized materials.

When glassy carbon is blended with a thermoplastic resin, the presence of incomplete carbonized or uncarbonized materials 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 materials or uncarbonized materials are considered to be the thermosetting resin itself which is the raw material resin for glassy carbon, or the thermally decomposed low polymer thereof.

On the other hand, one of the characteristics of the thermotropic liquid crystal polymer is a high melting point which can be said to be anomalous among the polymers, and therefore the molding temperature is extremely high. In such a case, the above-mentioned incompletely carbonized material or uncarbonized material contained in the glassy carbon is decomposed and is likely to cause gas generation. At high temperatures, especially in compression or molding under high pressure such as injection molding, the generation of gas, even in a small amount, becomes a fatal defect in a processing step or a molded product. For example, in an extreme case, molding itself is difficult due to gas generation, or blisters and flow marks are generated on the surface of the molded product, resulting in loss of the commercial value of the molded product.

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

In the separating claw for a copying machine of the present invention, in consideration of blending with the thermotropic liquid crystal polymer having a high melting point as described above, the weight loss under the conditions peculiar to the liquid crystal polymer is 5% by weight or less. It is preferred to use glassy carbon.

Here, the measurement of the weight loss is defined as the weight loss when heating from room temperature to 350 ° C. at a heating rate of 10 ° C./min and holding at that temperature for 30 minutes using, for example, a thermobalance. It Usually, the glassy carbon produced at a carbonization temperature above 800 ° C. has a weight loss of 5% by weight or less.

When the glassy carbon whose weight loss is more than 5% by weight under the above conditions is combined with the thermotropic liquid crystal polymer having a high melting point, gas is generated by heating during molding (non-carbonized thermosetting). It seems that the resin is decomposed), molding becomes difficult, the appearance of the molded product deteriorates, and blister (blister) occurs, resulting in a decrease in productivity and commercial value.

On the other hand, the shape is preferably spherical, and more preferably close to a true sphere. A non-spherical shape such as an irregular shape is not preferable when it is used for a member such as the separating claw for a copying machine of the present invention which requires sliding properties, because it causes abrasion of the metal or resin of the mating material.

The addition amount of spherical glassy carbon is 1
It is 0 to 70% 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 it is less than the above range, the wear resistance is insufficient, and even if the amount exceeds 70% by weight, further improvement of the wear resistance cannot be expected. In addition, the strength of the obtained molded product also decreases.

Various additives may be added to the thermotropic liquid crystal polymer composition used in the separating claw for a copying machine of the present invention.

The additives include inorganic fillers, organic fillers, stabilizers, UV absorbers, pigments, dyes, modifiers and the like. Among them, the inorganic filler is particularly important and is often used for improving workability and physical properties.

Examples of the inorganic filler include graphite, molybdenum disulfide, bronze, talc, mica, clay, sericite, calcium carbonate, calcium silicate, calcium phosphate, calcium pyrophosphate, silica, alumina, aluminum hydroxide, calcium hydroxide, fluorine. Graphite, potassium titanate and the like, glass fiber, carbon fiber,
It is possible to add various whiskers and the like as long as the effects of the present invention are not impaired.

The method for mixing the thermotropic liquid crystal polymer, the spherical glassy carbon, and the above-mentioned additive added to these is not particularly limited, and various means can be applied.

For example, they may be separately fed to the extruder for melt mixing, or they may be premixed with a mixer such as a Henschel mixer or a tumbler and then fed to the extruder.

In addition, the glassy carbon of the present invention can be added during the polymerization of the thermotropic liquid crystal polymer. Thus, even if the thermotropic liquid crystal polymer composition in which glassy carbon is blended at the time of polymerization is used, it goes without saying that when a processed product is produced, that is, the composition is prepared by molding such as injection molding or compression molding. In the case of molding, the thermotropic liquid crystal polymer is melt-molded and exposed to high temperature. Therefore, even in such a case, the predetermined effects of the present invention can be obtained.

Further, the separating claw for a copying machine according to the present invention is molded by a method such as injection, compression or extrusion of the composition thus obtained.

[0046]

The separating claw for a copying machine according to the present invention is most suitable as a separating claw for a copying machine operating at a high speed under a high load, when the mating member is a metal because of the following features.

(1) Among conventional plastics, since a polymer having a particularly high melting point is used, it is unlikely to cause melting and seizing due to frictional heat.

(2) Since a specific glassy carbon is used, less wear is obtained, and a metal material such as an aluminum alloy which is a counterpart member of the separating claw is less likely to be damaged.

(3) Since the composition used for the separating claw for a copying machine of the present invention uses a thermotropic liquid crystal polymer, it has a high melting point but has a good fluidity at the time of melting so that it can be easily molded. is there.

[0050]

EXAMPLES The present invention will be described in more detail by way of examples, which should not be construed as limiting the scope of the present invention, but showing preferred embodiments of the present invention. First, the raw materials used in Examples and Comparative Examples are collectively shown.

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

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

Spherical glassy carbons a to d are spherical glassy carbons obtained by firing carbonization of a thermosetting resin. a: Bell Pearl C-800 (trade name) b: Univex GCP-50 (H) (trade name) c: Bell Pearl C-2000 (trade name) d: Univex GCP-50 (L) (trade name) Bell Pearl ...・ Univex made by Kanebo Co., Ltd. ・ ・ ・ made by Unitika Co., Ltd.

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

It was confirmed that the fracture surfaces of the particles of each of these glassy carbons had a glassy luster, and
The X-ray diffraction spectrum measured by -Kα line (double line) also had a clear broad peak in the vicinity of the diffraction angle (2θ) of 23 to 25 °. Further, in the glassy carbon particles of a, b and d, the sharp peak peculiar to graphite was not substantially observed, but the carbon of c had a diffraction angle of 2θ.
At d = 26.4 degrees, the d ₀₀₂ peak was recognized as a shoulder.

Weight loss: from room temperature to 35 at a rate of 10 ° C./min.
Weight loss when the temperature was raised to 0 ° C and kept at this temperature for 30 minutes. (Seiko Denshi Kogyo's thermobalance SSC-5020
The measurement was performed by TG / DTA200. )

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

Glass fiber Milled glass fiber M manufactured by Asahi Fiber Glass Co., Ltd.
FA (trade name) Diameter 10 to 15 micron meter Length 30 to 100 micron meter

Examples 1 and 2 The above raw materials were blended in the proportions shown in Table 1, mixed with a Henschel mixer, and then melt-kneaded with a twin-screw extruder (PCM-30 type manufactured by Ikegai Tekko KK). (Temperature 420 ° C., screw rotation speed 200 rpm), and granulated into pellets.

Next, the pellets were put into an injection molding machine (Nestal SG-25, manufactured by Sumitomo Heavy Industries Machinery Co., Ltd.) at a cylinder temperature of 400 ° C., an injection pressure of 1000 kgf / cm ² and a mold temperature of 150 ° C., and a diameter of 5 cm. A disk having a thickness of 3 mm was molded. The obtained test piece was subjected to a pressure and pressure of 5 kgf / cm ² and a speed of 20 m / min using a Suzuki type friction and wear tester.
The wear coefficient and the wear amount of the mating material were measured by using a ring-shaped S45C steel having an outer diameter of 25.6 mm and an inner diameter of 20 mm as the mating material and aluminum.

Further, a bending test piece was molded under the same conditions using the above injection molding machine, and the obtained test piece was used for AS.
Bending strength was measured by TM D-790. Also,
At the same time, the moldability and its appearance were observed with 10 test pieces, and the number of blisters and flow marks generated was recorded.

Further, the above-mentioned injection molding machine was used to mold the separating claws for a copying machine under the same conditions. Further, the separation claw was evaluated by the presence or absence of scratches on the surface of the fixing roller (made of aluminum alloy) after copying 50,000 sheets of A4 paper by a copying machine using this separation claw in the fixing section of the copying machine. .. No scratches on the surface of the fixing roller, some scratches, and some scratches were indicated by ◯, Δ, and ×, respectively.

Examples 3 and 4 The above raw materials were blended in the proportions shown in Table 1, mixed with a Henschel mixer, and then melt-kneaded with a twin-screw extruder (PCM-30 type manufactured by Ikegai Tekko KK). (Temperature: 350 ° C., screw rotation speed: 200 rpm), and pelletized.

Next, the pellets were subjected to an injection molding machine (Nestal SG-25, manufactured by Sumitomo Heavy Industries Machinery Co., Ltd.) under the conditions of a cylinder temperature of 340 ° C., an injection pressure of 1000 kgf / cm ² and a mold temperature of 80 ° C., and a diameter of 5 cm. A disc having a thickness of 3 mm was molded, and the wear characteristics were measured in the same manner as in Example 1.

Further, using the above-mentioned injection molding machine, bending test pieces and separating claws 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, 5 The above raw materials were blended in the proportions shown in Table 2, and
In the same manner as in 2, pellet granulation, a disk, a bending test piece, and a separating claw were molded and evaluated. The results are shown in Table 2.

Comparative Examples 2, 4 and 6 The above raw materials were blended in the proportions shown in Table 2, and
In the same manner as in 4, the pellet granulation, the disc, the bending test piece, and the separating claw were molded and evaluated. The results are shown in Table 2.

Comparing Examples 1 to 4 with Comparative Examples 1 to 6, Examples 1 to 4 show that the ratios of the thermotropic liquid crystal polymer and spherical glassy carbon and the glassy carbon in air at 350 ° C. and 30 Since all of the weight loss in the desired range are within the desired ranges, all of the wear characteristics, mechanical strength, moldability, appearance, and characteristics as a separating claw are excellent.

On the other hand, in Comparative Examples 1 and 2, graphite and glass fiber, which have been conventionally used for improving the sliding property and the wear resistance, were used, but the wear coefficient was large, and in the case of the glass fiber, Indicates that the amount of wear of the mating material is also large. Especially, in the case of wear of the mating material, the difference is remarkable in the case of soft aluminum.

In Comparative Example 3, the spherical glassy carbon was 10
Since it is less than wt%, abrasion resistance is insufficient. Furthermore, in Comparative Example 4, the mechanical strength is insufficient because the amount of spherical glassy carbon exceeds 70% by weight.

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

[Table 1]

[Table 2]

[Brief description of drawings]

FIG. 1 is a schematic view of a fixing unit of a copying machine.

[Explanation of symbols]

 1 Separation Claw 2 Fixing Roller 3 Pressing Roller 4 Copier

Claims (4)

[Claims] 1. Thermotropic liquid crystal polymer (a) 9
A separating claw for a copying machine, which comprises 0 to 30% by weight and 10 to 70% by weight of spherical glassy carbon (b) characterized by having a glassy glossy surface. 2. The separating claw for a copying machine according to claim 1, wherein the glassy carbon has a weight loss of 5% by weight or less when kept in air at 350 ° C. for 30 minutes. 3. The separating claw for a copying machine according to claim 1, wherein the thermotropic liquid crystal polymer is wholly aromatic polyester. 4. The thermotropic liquid crystalline polymer contains at least a monomer unit represented by the following general formula (co).
4. The separating claw for a copying machine according to claim 1, which is a polymer. [Chemical 1]