JPH10274896A - Separation pawl of copying machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a separation pawl of a copying machine which is a formed body having excellent resistance against thermal load and resistance against thermal fatigue and to which a fluorocarbon resin is applied to enhance the non-adhesive property of the surface of the pawl by the intrinsic characteristics of the resin. SOLUTION: The base body of the separation pawl is a formed body of a polyether ketone resin, preferably consists of a formed body compsn. essentially comprising a polyether ketone resin expressed by the formula and having >=350 deg.C melting point with addition of specified proportions of the reinforcing material such as zinc oxide whisker and a solid filler such as graphite and fluorocarbon resin. Further, a fluorocarbon resin film such as tetrafluoroethylene- perfluoroalkylvinylether copolymer is formed by melting and applying on the surface of the body.

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 for separating copying paper from a roller surface.

[0002]

2. Description of the Related Art Generally, in a dry copier, a toner image is transferred to a paper surface, and the transferred toner image is heated and pressed by a fixing roller to fuse the toner image and the paper surface, thereby facilitating both. A fixing device that keeps the user from moving away is incorporated.

In such a fixing device, in order to reliably discharge the copy paper that has passed through the fixing roller without winding it around the roller, a separation claw is used, and the copying paper is copied while the leading end thereof is in close contact with the outer peripheral surface of the roller. Means of picking up the edges of the paper are taken.

[0004] The characteristics required for such a separating claw for a copying machine include that the frictional resistance is small and the surface of the roller is not damaged, that it has sufficient mechanical strength, and that it has high-temperature rigidity, The shape of the tip portion is formed with sufficient precision and does not deform, and further, the toner does not stick.

In particular, the adoption of the digital signal system in recent years has led to a so-called intelligent copying machine having not only a simple copying function but also a high-resolution image processing and editing function, a facsimile function, and an input / output device of another OA device. Therefore, higher copy speed, higher reliability, and longer life are required than ever, and the separation claw is also required to be increased due to the increase in the heating temperature of the fixing roller.
A heat resistance of at least ℃ is required.

As a molding material (structural base material) of a separating claw for a copying machine having a glass transition point of about 250 ° C. or more, there are polyether sulfone, polyetherimide, etc., which are lubricating and abrasion resistant. Is poor, the fluororesin film formed on the surface is worn away, and the function is extremely deteriorated when the base material comes into direct contact with the roller.

Conventionally known polyetherketone resins have a glass transition point of less than about 250 ° C., but the resin itself has toughness, so that only a small amount of reinforcing agent is required, and the resin is reinforced like potassium titanate fiber. Although the effect is small, it can be reinforced only with fibers that do not damage the sliding partner material. Therefore, the aggressiveness of the partner roll is low, the brittleness due to oxidative crosslinking is hardly exhibited, and the heat aging resistance is excellent.

Japanese Patent Application Laid-Open Nos. 60-257467 and 61-27575 disclose a separating claw for a copying machine comprising such a polyetherketone resin as a main material and a molding material reinforced with potassium titanate fiber. Have been described.

By the way, on the surface of the separating claw for a copying machine, in order to improve the non-adhesiveness for preventing the adhesion of toner and the like,
Usually, a fluororesin film is formed, and there are the following two types of this film in view of the structure.

One type is a coating made of an enamel type fluororesin coating agent in which a fluororesin is mixed with a binder resin such as an epoxy resin or a phenol resin in which an organic solvent is dispersed. In order to fix this to the surface of the separation nail substrate, the binder resin is heated to a melting temperature or a curing temperature (generally, about 180 to 250 ° C.). Since the resin and the binder resin are mixed, the non-adhesive property inherent to the fluororesin could not be exhibited.

Another type is a fused film of a fluororesin formed on the surface of the nail base by heating the fluororesin above its melting point. Since the entire surface of the film is made of a fluororesin, the non-adhesive property inherent to the fluororesin can be exhibited.
As a fluorine resin having good non-adhesiveness when fused, a melting point of a tetrafluoroethylene-perfluoroalkylvinyl ether copolymer (PFA) or the like is about 35.
Those having 0 degrees or more are mentioned.

[0012]

However, as described above, the conventional separation claw for a copying machine made of a polyetherketone resin is excellent in heat aging resistance, but depending on the fiber reinforcing material, sufficient heat deformation resistance is not obtained. When a paper jam occurs under the same temperature condition as the surface temperature of the fixing roller (about 150 ° C. to 250 ° C.) and a force larger than usual is applied to the nail tip, the nail tip cannot be maintained. There is a problem in heat load resistance as seen in the phenomenon of creep deformation.

In addition, the separation nail for a copying machine made of the above-mentioned polyetherketone resin, when exposed to a temperature higher than the glass transition point for a long time, rapidly deteriorates in mechanical properties such as an elastic modulus. There is also a problem.

In a separating nail for a copying machine having a fluororesin film formed on the surface, the fluororesin is heated to a melting point or higher to form a fused film of non-adhesive fluororesin on the surface of the nail base. In order to do so, the nail base material is required to have heat resistance of 350 ° C. or more, but a resin material having such heat resistance and having the heat load resistance and heat fatigue resistance as described above has been separated. No examples have been tried as nail bases.

Therefore, an object of the present invention is to solve the above-mentioned problem, and to provide a separation claw for a copying machine excellent in heat load resistance to such an extent that the claw tip does not undergo creep deformation even under a condition where a load is applied at a high temperature. In addition, it is necessary to form a molded body having excellent thermal fatigue resistance so that it does not fatigue even when exposed to a temperature higher than the glass transition point for a long time.

Another object of the present invention is to provide a separation nail for a copying machine in which a coating excellent in the inherent non-adhesive property of a fluororesin is formed on the surface of a nail base.

[0017]

In order to solve the above-mentioned problems, according to the present invention, a separating claw for a copying machine is used.
It was composed of a molded product of a polyetherketone resin at 50 ° C. or higher.

Further, the separation claw for a copying machine has a melting point of 350 ° C.
Using the above molded product of polyetherketone resin as a base material,
A fused film of a fluororesin was formed on the surface.

The copying machine referred to in the present invention includes a dry electrostatic copying machine of a toner image transfer type, a wet electrostatic copying machine, a laser beam printer, a liquid crystal printer, a facsimile printer, and the like, such as PPC, LBP, LED, LCD, CR
It refers to general image forming apparatuses such as printers such as T and printing machines.

As the polyetherketone resin, a polyetherketone resin represented by the following formula (2) can be employed.

[0021]

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In the above-described separation claw for a copying machine,
It is also possible to adopt a configuration in which the molded body is made of a composition in which a fibrous reinforcing material is further blended with 10 to 50% by weight to a polyetherketone resin.

Further, in the above-described separation claw for a copying machine,
The molded body contains a solid filler in an amount of 3 to 15% by weight, and the total amount of the solid filler and the fibrous reinforcing material is 50% by weight or less of the total composition. You can also.

The details will be described below. As the polyetherketone resin (hereinafter abbreviated as PEK) used in the present invention, a ketone polymer having a melting point of 350 ° C. or more can be employed without limitation. Polyetherketone resin has an ether bond (-O-) and a ketone bond (-
And C0-) and having an aromatic ring bonded thereto. Examples thereof include those represented by the following Chemical Formula 2 and those represented by the following Chemical Formulas 3 and 4. These are all crystalline resins, and their physical properties and trade names of commercial products are as follows.

[0025]

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[0026]

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[PEK represented by Chemical Formula 2] Glass transition point (Tg) = about 170 to 175 ° C., melting point (Tm) = 37
5-381 ° C, manufactured by BASF: Ultrapek-A2
000, [PEK represented by Chemical Formula 3] Glass transition point (Tg) =
165 ° C, melting point (Tm) = 365 ° C, manufactured by ICI: VI
CTREX PEK-220G, [PEK represented by Chemical Formula 4] Glass transition point (Tg) =
160 ° C., melting point (Tm) = 360-380 ° C., manufactured by Hoechst: HOSTATEC, and other commercially available products having a melting point of 350 ° C. or higher that can be used in the present invention include Kadel, manufactured by Amoco. These polyketone polymers are made of PE
KEKK, PEKK, PEAK, etc. may be subdivided and referred to.

Next, the type of the reinforcing material used in the present invention is not particularly limited, and potassium titanate whisker, titanium oxide whisker, zinc oxide whisker, aluminum borate whisker, graphite whisker, calcium sulfate whisker, carbonic acid whisker, Whiskers such as calcium whiskers, basic magnesium sulfate whiskers, silicon carbonate whiskers, wollastonite, zonolite, and magnesium oxide whiskers are fine, and can be efficiently reinforced at the tip of the nail, and are therefore preferred. These whiskers are relatively fine compared to general carbon fibers, glass fibers, and the like, and are generally in the form of powder and fibers. In addition, carbon fibers, glass fibers, aromatic polyamide fibers, and the like can be used in consideration of the degree of not attacking the partner roll.

Among the above-mentioned whiskers, titanium oxide whiskers, zinc oxide whiskers, and potassium titanate whiskers are preferable because they improve abrasion resistance. In addition,
As shown in FIGS. 1A and 1B, the zinc oxide whiskers are of a four-axis radial type and have a tapered shape in which each axis becomes smaller in diameter toward the tip. Commercially available such zinc oxide whiskers include Matsushita Amtech; Panatetra.

A zinc oxide whisker, such as ZnO, is vaporized from metal zinc and oxidized in the gas phase to synthesize the whisker.
At a high temperature oxidation of 00 ° C. or more and a high Zn concentration of about 4% or more, whiskers can be produced with an increase in the particle size.

It is considered that most of such zinc oxide whiskers are broken at the time of kneading and molding of the matrix resin, and exist in a tapered shaft state as shown in FIG. 1 (b). The tapered shaft is difficult to fall out of the resin when exposed to the sliding surface, and it is easy to orient and enter the tip of the claw,
That is, it is considered that the claw tip is efficiently reinforced. For this reason, the zinc oxide whisker has a length of each axis of 2 to 50.
Preferably, the diameter is 0.2 μm and the diameter of the shaft is 0.2 to 3 μm.

The amount of such a fibrous reinforcing agent in PEK is 10 to 50% by weight based on the total amount of the composition. If the amount of the fibrous reinforcing agent is less than 10% by weight, a sufficient reinforcing effect cannot be obtained.
This is because uniform mixing with the resin cannot be performed, and the fluidity of the resin is lost, making molding difficult.

As the solid filler used in the present invention, a known solid lubricant or the like having an effect of reducing the friction coefficient of the surface of the molded body serving as the nail base can be employed. Examples of such a solid lubricant include graphite, fluororesin powder, molybdenum disulfide, graphite fluoride, and lead monoxide. Among such solid lubricants, graphite and fluorocarbon resin are particularly preferable because they improve the non-aggressiveness to the roller together with the effect of reducing the frictional resistance.

Examples of the solid filler having a thermal decomposition temperature equal to or higher than the melting point of the predetermined polyetherketone polymer used in the present invention include a thermosetting resin or a thermoplastic resin having such a thermal decomposition temperature.

The pyrolysis temperature mentioned here can be measured by gravimetric analysis or the like. Specifically, it is determined by a thermal analysis (DSC, DTA, TGA, etc.) using a thermobalance weight loss curve (TG), a differential thermal analysis curve (DTA), and the like.
5 mg) in air or nitrogen gas at a heating rate of about 10 ° C./min, for example, at a temperature at which the specimen loses, for example, about 5%, or at a temperature, for example, at which about 5 mg loses weight. Examine the weight loss% at each temperature, and find the temperature corresponding to about 50% by weight using the 50% weight loss temperature by thermal decomposition as a guide, and evaluate it as the differential thermal decomposition onset temperature Can be.

Examples of thermosetting resins that can satisfy such a thermal decomposition temperature include phenolic resins, urea resins, melamine resins, unsaturated polyester resins, diallyl phthalate resins, epoxy resins, and silicon resins. , Polyurethane-based resin, furan-based resin, polyimide-based resin, and the like, and as the polyimide-based resin, condensation-type polyimide resin and bismaleimide-based, terminal nadic acid-based, acetylene-based addition-type polyimide resin and the like. Can be Some of them show fusibility.

Among the above-mentioned thermosetting resins, phenolic resins, in particular, phenolic resins are generally used in terms of mechanical properties, heat / cold resistance, dimensional stability, solvent resistance, acid resistance, water resistance and price. In terms of physical properties, they are relatively well-balanced and excellent in mechanical strength retention especially at high temperatures, and the differential thermal decomposition onset temperature is about 405 ° C.

Among the phenolic resins, a novolak resin having relatively excellent moldability is used as a molding material, and a resol resin has a better thermal shock resistance than a novolak resin. Also, resol-based one-step molding materials are:
It requires more time for production than the two-step method, and has a characteristic that the curing speed is slow.

In addition to the phenolic resin, the epoxy resin, silicon resin, and polyimide resin have differential thermal decomposition onset temperatures of about 390 ° C., about 505 ° C., and about 40 ° C., respectively.
The temperature is about 0 to 550 ° C, and these resins are also excellent in mechanical strength at a high temperature and have a differential thermal decomposition onset temperature of about 390 ° C or more, preferably about 400 ° C or more. This is because the molding material is used at a high temperature of about 380 to 420 ° C. during pellet granulation in a twin screw extruder or at about 390 during injection molding.
Cylinder temperature of ℃ 420 ° C. and then about 250
This is because the thermal decomposition progresses relatively slowly at the time of heat treatment at 340 ° C., and also at various production steps such as firing at about 340 ° C. to 350 ° C. in the case of PFA resin.

3 to 10% by weight of these thermosetting resins,
Preferably, the addition of 5 to 8% by weight can further improve the impact resistance and wear resistance of the cutting edge of the separation claw.

In this case, a small amount of less than 3% by weight of the thermosetting resin has little effect on the improvement of impact resistance, abrasion resistance, heat resistance, etc. When a predetermined polyketone-based polymer is melted at a relatively high temperature such as about 390 to 420 ° C. to perform injection molding or the like, stable granulation and injection can be performed due to inconvenience such as progress of thermosetting in a cylinder. This is because moldability and dimensional accuracy cannot be expected.

On the other hand, as typical examples of the above-mentioned thermoplastic resins, there may be mentioned the following fluorinated resins.
In addition, [] shows the thermal decomposition temperature.

Polytetrafluoroethylene (PTF
E), [about 508-538 ° C] tetrafluoroethylene-perfluoroalkylvinyl ether copolymer (PFA), [about 464 ° C or more] tetrafluoroethylene-hexafluoropropylene copolymer (FEP), [about 419 ° C or more] ] Polychlorotrifluoroethylene (PCTFE)
[About 347 to 418 ° C] Tetrafluoroethylene-ethylene copolymer (ET
FE), [about 347 ° C. or more] chlorotrifluoroethylene-ethylene copolymer (ECTFE), [about 330 ° C. or more] polyvinylidene fluoride (PVDF), [about 4
00 to 475 ° C.] polyvinyl fluoride (PVF), [about 372 to
480 ° C.] tetrafluoroethylene-hexafluoropropylene-perfluoroalkylvinyl ether copolymer (E
PE).

The fluororesin may be a fluorinated resin such as two or more copolymers or terpolymers in which the above-mentioned fluororesin monomer has a polymerization amount of, for example, about 1:10 to 10: 1. It may be a polyolefin or the like, which also exhibits properties as a solid lubricant. Among these, PTFE, PF
Perfluoro fluororesins such as A and FEP have a form in which all around the carbon atoms as the skeleton are surrounded by fluorine atoms or trace amounts of oxygen atoms. It is excellent in various properties such as non-adhesiveness and low coefficient of friction and can be said to be preferable.

These fluororesins are also preferred because they have a relatively high differential pyrolysis onset temperature. For example, PTFE, P
The decomposition points of VDF are about 490 ° C. and about 350 ° C., respectively.
5 ° C, about 460 ° C.
TFE, PFA, and FEP are preferable because they have excellent high-temperature characteristics. Therefore, it can relatively endure a number of heat histories as described above in the process of manufacturing a separation nail made of a predetermined polyketone-based polymer by melting or the like. In particular, the decomposition point of PTFE is preferable because it is higher than the melting point of a predetermined polyketone polymer. By adding these thermoplastic resins in an amount of 3 to 10% by weight, preferably 5 to 8% by weight, the aggressiveness of the cutting edge of the separation claw on the fixing roller surface can be reduced, and the impact resistance, fatigue resistance, and It is considered that the wear property can be improved.

If the added amount is less than 3% by weight, these effects cannot be expected. If the added amount is more than 10% by weight, their melting viscosities and the like may cause the above-mentioned problems during granulation or injection molding. This is because the load on a cylinder of a machine or the like is large, and stable granulation, injection moldability and dimensional accuracy cannot be expected.

Incidentally, the melt viscosities of PFA and FEP are about 10 ⁴ to 10 ⁵ poise and about 4 × at 380 ° C., respectively.
10 ⁴ to 10 ⁵ poise, especially about 34 in PTFE.
It becomes about 10 ¹¹ to 10 ¹² poise at 0 to 380 ° C., and a thermoplastic resin having a viscosity property of about 10 ⁴ to 10 ¹² poise even at such a high temperature has a high viscosity property. , And excellent in heat resistance.

As a solid lubricant other than those described above,
Aromatic polyamide resin (hereinafter aramid resin) powder is exemplified. This can further improve the abrasion resistance of the composition when added in an amount of 3 to 5% by weight. As a commercial product of the powdery aramid, Aramika ARP-P (average particle size: 20 μm) manufactured by Asahi Kasei Corporation can be mentioned.

The other aramid resin powder is represented by the following chemical formula
A typical example of an aramid resin having a meta-based molecular structure among such resins is Nomex (paper-like) manufactured by DuPont of the United States, manufactured by Teijin Limited. : Connex is mentioned,
Representative examples of resins having a para-based molecular structure include Kevlar (fibrous) manufactured by DuPont in the United States and Technora manufactured by Teijin Limited.

[0050]

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The para-aramid resin added to such a composition has high elasticity and high strength in the axial direction because the molecular chains are arranged in the axial direction, but the intermolecular force in the perpendicular direction is low. It is weak. As described above, the para-aramid resin can improve the abrasion resistance of the compounded resin composition by the strength in the axial direction, while the molecular chain buckles when subjected to a compressive force in a direction perpendicular to the molecular chain. Or, it is considered that the soft sliding partner material is not damaged because it is easily broken.

When an aramid resin other than a para-based resin is employed, a resin containing a predetermined amount of the above-mentioned fluororesin, such as ethylene tetrafluoride resin, is added.
Similar to the above composition, the composition has excellent abrasion resistance without damaging a soft sliding partner.

In this case, another fluorine-based resin can be used in combination. Among such aramid resins, the fibers have a fiber length of about 0.15 to 3 mm and an aspect ratio of about 1 to 230.

In the present invention, among the above-mentioned aramid resins, powdery or powdered ones are employed. In a resin composition containing a fibrous aramid resin, fibers oriented on the sliding surface appear like a brush, and the sliding partner is easily damaged, which is not preferable.

Then, such aramid resin powder is
It is preferable to employ one having an average particle size of about 5 to 50 μm. This is because, with small particles having an average particle size of less than about 5 μm, the resin composition cannot acquire sufficient abrasion resistance,
This is because large particles exceeding about 50 μm may damage the sliding partner material. As a commercially available powdery aramid satisfying all of these conditions, it is considered that Aramica ARP-P (average particle size: 20 μm) manufactured by Asahi Kasei Corporation is preferable.

The amount of the solid lubricant is 3 to 15% by weight of the total composition. When the amount is less than 3% by weight, the effect of reducing frictional resistance and the effect of non-aggression on the outer peripheral surface of the mating roller are not sufficient, and when the amount is more than 15% by weight, the fluidity of the composition is remarkably deteriorated. The reason for this is that the heat-resistant deformation resistance of the molded article also decreases significantly, which is not preferable. In view of such a tendency, a more preferable blending amount is 5 to 8% by weight.

The total amount of the solid lubricant and the above-mentioned fibrous reinforcing material is 50% by weight or less, preferably 10 to 50% by weight of the whole composition. If the total amount exceeds 50% by weight of the total composition, mixing cannot be sufficiently performed to obtain a homogeneous composition, and the melt fluidity of the resin is lost, making molding difficult. The total amount is 10% of the total composition.
If the amount is less than 10% by weight, a sufficient reinforcing effect cannot be obtained in the composition.

In order to mix the above-mentioned molding materials, they may be individually supplied to a melt mixer, or may be dry-mixed in advance with a general-purpose mixer such as a Henschel mixer, a tumbler mixer, a ribbon blender, or the like. May be supplied to the melt mixer.

Then, the mixed molding material is 400 to 4
After heating to a temperature range of 20 ° C. and plasticizing, the mixture is filled in a mold, solidified and released from the mold to obtain a separation claw for a copying machine made of a desired molded product.

The reason for the high temperature is that the melting point of the predetermined polyketone polymer is about 350 ° C. or more, and about 350 to 360 ° C. or more depending on the degree of polymerization of ether bond or ketone bond, measurement conditions, and the like. That's why.
Further, by performing a predetermined heat treatment on the separation claw, a separation claw for a copying machine having excellent heat resistance, dimensional stability, and abrasion resistance and having a long life can be obtained.

The heat treatment may be performed at about 150-340 ° C., preferably about 200-330 ° C., for about 0.5-24 hours or more, preferably about 0.5-8 hours or more. If the temperature exceeds about 340 ° C., remarkable thermal deformation occurs in the separation claw, which is not preferable in practical use.
If the temperature is less than the glass transition point (Tg), the crystallization does not progress relatively, so that the moldability and the heat deformation resistance cannot be improved.

[0062] Even if a polyketone-based polymer or a crystalline polymer is a polymer whose crystallinity is appropriately suppressed by a device of the molecular structure, it is excellent in dimensional stability, and heat treatment or the like is omitted. You may.

Next, the fused film of the fluororesin according to the present invention is obtained by coating the surface of the molding composition of the above-mentioned material with the powder or dispersion of the fluororesin and heating it to a melting point or higher during firing. It is formed by melting a fluorine-based resin and continuing to the surface of the molded body.

Among the above-mentioned fluorine-based resins that can be employed as the fusion coating component, among the above-mentioned compounds, tetrafluoroethylene resin (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), and tetrafluoroethylene- Low-molecular-weight fine powder (fused type) for powder coating, such as perfluoroalkyl vinyl ether copolymer (PFA), may be used.

As such a commercially available fusion type fluorine-based resin coating agent, there are PFA-X500CL manufactured by DuPont-Mitsui Fluorochemicals, Vidax AR manufactured by DuPont. A coating agent of the type to be fused may be added with a reinforcing agent or a lubricant to improve the abrasion resistance, and may be added with a conductivity imparting agent such as carbon black to prevent the separation nail from being charged. it can.

As a means for applying such a fluororesin to the surface of the resin composition, a spray coating method, a dip coating method, an electrostatic coating method, a powder coating method, or the like can be employed. Further, a predetermined primer may be applied before painting as needed.

Baking (heating) after such coating
In the process, the temperature may be increased stepwise and fired at a maximum of about 350 ° C. for about 30 minutes.

The thickness of the film to be formed is about 5 to 4
Preferably, it is 0 μm. This is because a thin film having a thickness of less than about 5 μm is inferior in wear resistance, and a thick film having a thickness of more than about 40 μm is difficult to form a predetermined round shape of a nail tip required for a separation nail.

[0069]

The separating claw for a copying machine according to the present invention has a melting point of 35.
Since it is made of a molded body of PEK at 0 ° C. or higher, it has excellent load resistance and thermal fatigue resistance during high-temperature heating. Molded with a composition filled with fibrous reinforcement, rigidity,
The mechanical strength is even better.

Further, those molded with a composition further containing a solid lubricant are excellent in abrasion resistance and impact resistance in addition to the above-mentioned characteristics, and become highly reliable separation nails that can be used for a long time.

Further, since a completely continuous fused film of a fluororesin is formed on the tooth tip or the entire surface of the separation claw, the adhesion of the toner can be prevented very efficiently due to the inherent non-adhesion of the fluororesin.

[0072]

EXAMPLES The raw materials used in Examples and Comparative Examples are collectively shown below. In addition, the compounding ratio of these raw materials is all shown below by weight%.

(1) Polyetherketone resin (PEK represented by the above formula (2)), manufactured by BASF: Ultra
pek-A2000, melting point 375-381 ° C., (2) polyetherketone resin (PEK represented by the above formula (3)) manufactured by ICI: PEK-220G, melting point 3
65 ° C., (3) polyetherketone resin (PEK represented by the above formula (4)) manufactured by Hoechst: HOSTATEC, melting point: 360-380 ° C., (4) polyetherketone resin (represented by the following formula (6)) PEK) manufactured by ICI: PEEK150P, melting point 33
4 ° C,

[0074]

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(5) Titanium oxide whisker manufactured by Ishihara Sangyo: FTL100 (6) Zinc oxide whisker manufactured by Matsushita Amtech: Panatetra, (7) Potassium titanate whisker manufactured by Otsuka Chemical: TISMO-N, (8) Graphite Kanebo Manufactured by: Bellpearl C2000 (9) Tetrafluoroethylene resin [PTFE] manufactured by Kitamura: KTL 610 (10) Coating primer solution: manufactured by Mitsui / DuPont Fluoro Chemical Co .: MP-902AL (11) Coated PFA solution: Mitsui / Dupont Fluoro Chemical Co .: X500CL [Examples 1 to 8, Comparative Examples 1 to 3] After the respective raw materials are dry-mixed in advance at the mixing ratios shown in Table 1 or Table 2, a twin-screw extruder (PCM- manufactured by Ikegai Iron Works Co., Ltd.) 30) and 380
The mixture was kneaded and extruded under the conditions of ~ 420 ° C and granulated. The obtained pellets are supplied to an injection molding machine and the cylinder temperature is 390.
Injection molding was performed under the conditions of ~ 420 ° C, injection pressure of 1000 kg / cm ² , and mold temperature of 200 ° C to obtain a molded product having a separation claw shape (a separation claw shape used in a general copying machine). This molded article is subjected to a heat treatment at 320 ° C. for 5 hours, spray-coated with a primer solution for coating (10), dried, and further coated with PF
A coating solution (11) was spray-coated in the same manner. It was heated at 350 ° C. for 30 minutes and fused to form a test piece.

With respect to the obtained test pieces, abrasion resistance,
The impact resistance and the amount of filling at the tip of the nail were examined.
Or, it is also described in Table 2. The measurement and evaluation methods are as follows.

Abrasion Resistance As shown in FIGS. 2A and 2B, the separation claw 1 is moved at a temperature of 196 ± 3 ° C. and a rotation speed of 148 rpm with respect to the mating roller 2.
m, a load of 20 gf, and a sliding contact under the conditions of 350 hours, and the difference (m) in the distance L ′ from the center of the hole diameter before and after the test to the tip of the claw (m
m) was measured.

Impact Resistance The impact was measured using a high impact tester (schematic diagram shown in FIG. 3) at the tip of the blade of the separation claw. That is, the lever (length L = 8
5 mm), the other end of the lever is rotatably supported, and when this is spontaneously rotated from an upright state to a horizontal state, the tip of the blade edge of the separation claw 1 is a roller. 2, load (W) 20 gf, contact angle (θ) 1
The collision was performed under the condition of 00 °, and the number of collisions until a defect occurred in the separation claw 1 was measured. The number of collisions is 1
0 times was the upper limit.

Amount of filling at the tip of the nail The side of the tip of the separating nail is mirror-finished using a lapping machine, and the amount of whisker is observed with a scanning electron microscope (SEM). The evaluation was made in three grades: a circle marked with a mark and a triangle marked with almost no filling.

[0080]

[Table 1]

[0081]

[Table 2]

As is clear from the results of Tables 1 and 2, Comparative Example 1 using PEK having a melting point of 350 ° C. or less was used.
Was deformed by the heat of firing of the coated PFA. In Comparative Example 2 in which the fibrous reinforcing material was not filled, the abrasion resistance,
The results of the impact resistance were inferior to those of the examples. Further, Comparative Example 3, in which a fibrous reinforcing material exceeding a predetermined amount was blended, could not be molded.

On the other hand, Examples 1 to 8 satisfying all conditions exhibited excellent results in all test items such as moldability, abrasion resistance, impact resistance, and whisker filling amount at the tip of the nail. Obtained.

[0084]

As described above, the present invention provides a polyetherketone resin having a predetermined melting point,
The separation claw for copiers has excellent heat load resistance so that the tip of the claw does not creep even under conditions where a load is applied at high temperatures, and does not fatigue even if exposed to temperatures above the glass transition point for a long time. There is an advantage that the thermal fatigue resistance is excellent.

Further, a fusion coating having excellent non-adhesive properties is formed on the surface of a nail base made of a molded article of a polyetherketone resin having a predetermined melting point by heating the fluororesin above the melting point. In the case where the adhesive coating is formed, there is an advantage that the completely non-adhesiveness of the fluororesin is exhibited by a completely continuous fused film of the fluororesin, and the adhesion of the toner can be prevented very efficiently.

[Brief description of the drawings]

FIG. 1A is an enlarged perspective view illustrating the crystal structure of a four-axis radial zinc oxide whisker. FIG. 1B is an enlarged perspective view illustrating the shape of a broken axis of the zinc oxide whisker.

2A is a side view of a separating claw for a copying machine used for a wear resistance test; FIG. 2B is a schematic side view illustrating a measurement state of a wear resistance test;

FIG. 3 is a schematic side view of an impact resistance tester.

[Explanation of symbols]

 1 Separating Claw 2 Roller 3 Weight R Separating Claw Tip Angle L 'Distance L Lever Length θ Contact Angle W Load

──────────────────────────────────────────────────の Continued on front page (51) Int.Cl. ⁶ Identification code FI (C08L 71/10 27:12)

Claims (9)

[Claims] 1. A separating claw for a copying machine comprising a molded product of a polyetherketone resin having a melting point of 350 ° C. or higher. 2. A separating claw for a copying machine, comprising a molded body of a polyetherketone resin having a melting point of 350 ° C. or higher and a fused film of a fluororesin formed on the surface thereof. 3. The separation nail for a copying machine according to claim 1, wherein the polyetherketone resin is a polyetherketone resin represented by the following formula: Embedded image 4. The separation nail for a copying machine according to claim 1, wherein the molded body is made of a composition obtained by further blending a reinforcing material with a polyetherketone resin in an amount of 10 to 50% by weight. Characteristic separation claw for copier. 5. The separation nail for a copying machine according to claim 4, wherein the molded body contains 3 to 15% by weight of a solid filler, and a total amount of the solid filler and the fibrous reinforcing material is a total composition. Of 50
A separating claw for a copying machine, wherein the separating claw is a molded product comprising a composition of not more than% by weight. 6. A separating claw for a copying machine, wherein the solid filler according to claim 5 is a resin having a thermal decomposition temperature equal to or higher than the melting point of the predetermined polyetherketone resin. 7. The separation claw for a copying machine according to claim 5, wherein the solid filler is a thermosetting resin. 8. The separating claw for a copying machine according to claim 5, wherein said solid filler is a thermoplastic resin. 9. The separation claw for a copying machine according to claim 5, wherein said thermoplastic resin is a fluorine-based resin.