JP2931583B2 - Copier - Google Patents

Description

BACKGROUND OF THE DETAILED DESCRIPTION OF THE INVENTION [0001] This invention is related to a copying machine. 2. Description of the Related Art A dry-type copying machine, which has undergone rapid progress and development with the socialization of information, uses an electrostatic latent image formed on the surface of a photosensitive drum corresponding to characters, figures, etc. of a document as a toner. After the toner image is converted into an image, the toner image is transferred to the paper surface supplied from the paper supply cassette, and the surface is heated and pressed by a heated fixing roller to fix the transferred toner image on the paper surface. It has a mechanism for fusing the image and the paper fibers so that they do not separate easily. However, in such a device, for example, in the final fixing step, the paper heated and pressed by the fixing roller rotates while keeping in close contact with the roller surface, and there is a great risk of causing paper jams. It is important to lift the edge of the paper that is in close contact with the roller by using a separation claw whose tip is pressed against the surface of the roller to smoothly separate it. Therefore, it is natural that the separation claw needs to have heat resistance so that the tip does not deform, but at the same time, the radius of curvature of the tip (hereinafter, abbreviated as the tip R).
The small or comb, and or to have a lubricity to the separation claw, (which is hereunder referred to as separating direction failure) the fixing sheet to the fixing roller side send it would separation failure or paper at the separating claw unit jamming (hereinafter this Is simply called a paper jam). Further, the surface of the fixing roller is 170-27.
Since the temperature rises to 0 ° C., the toner adhered to the paper fuses to the separation claw, and if the amount increases, the fused toner may cause paper jam or cause the toner adhering to the paper to be scraped off. In many cases, white streaks (hereinafter referred to as nail marks) are formed in the toner fixing portion of the toner, so that the separating nails must be non-adhesive to the toner in order to avoid this. [0006] In order to satisfy the conditions to be met by such a separating claw, conventionally, polyimide, polyamideimide, polyarylene sulfide, aromatic polyetherketone, aromatic polysulfone, aromatic polyetherimide, aromatic polyamide, aromatic polyamide, Resins such as polyester or those obtained by mixing such resins with fluororesins such as tetrafluoroethylene resin or graphite or other solid lubricants. Further, for example, Japanese Utility Model Publication No. 54-18921,
As disclosed in JP-A-1111569, a resin in which the surface of a resin as described above is coated with a fluorine-containing polymer to improve lubricity and non-adhesion has been put to practical use. [0007] However, the separation claw whose surface is not coated with a fluorine-containing polymer has insufficient lubricity and non-adhesiveness even if mixed with a fluororesin or a solid lubricant, so that paper jamming occurs. Even with separation nails that cause the problem of nail marks and that have a surface coated with a fluorine-containing polymer, both the expected lubricity and anti-adhesion are insufficient, and long-term continuous use or depending on the type of toner, paper The problem of jamming and nail marks occurs as in the case described above. Generally, the thickness of the coating film at the tip of the separation claw is 30 μm on average and at least 10 μm or more in order to exhibit lubricity and non-adhesive effects. The tip R of the nail becomes large, and the separation direction is poor, and paper jams are likely to occur. Therefore, in order to prevent the tip R of the separation claw from being increased by the thickness of the coating film, a measure may be taken to reduce the tip R in consideration of the film thickness when forming the separation claw. However, in such a treatment, the tip is naturally susceptible to thermal deformation, not only lowering the usable temperature, but also the resin-made separation claw body and the fluorine-containing polymer are not usually firmly bonded. Therefore, interface peeling of the coating film easily occurs, and in order to coat the fluorine-containing polymer, a method of applying a fluorine-containing polymer dispersed in a polar solvent to about 20 to 40 μm by spraying is usually adopted. In addition, there are many problems, for example, since the splash is scattered around the separation claw, the product yield is reduced, and the cost is very high. There is an attempt to form a thin film of silicone oil on the surface of the separation claw by, for example, a dipping method so as to exhibit lubricity and non-adhesiveness. Long-term maintenance is not possible. [0010] As described above, the tip coating of the separation claw based on the prior art has lubricating properties, non-adhesiveness, and the like.
None of them are excellent in all aspects of adhesion strength and thin film forming ability, and there is a problem that undesired phenomena such as thermal deformation, poor separation direction, paper jam, and nail marks often occur. [0011] In order to solve the above-mentioned problems, according to the present invention, the surface of the roller is set to 170.
℃ and fixing roller that is heated above, a copying machine comprising a polyarylene sulfide resin separation claw for separating the fixing sheet from the fixing roller, the leading end portion of the separation claw
Is formed into an R shape having a radius of curvature of 0.1 mm or less, and the surface of at least the leading end of the separation claw on the paper passing surface is covered with the following predetermined fluorinated polyether polymer. The copying machine that was the feature was adopted. In the above means, the fluorinated polyether polymer is represented by the following formula: [0014] a main structural unit, Ru fluorinated polyether polymer der that is terminally linked at least one polar group. [0015] [action] fluorinated polyether polymer in the present invention, per se lubricity, both a polymer having a non-tacky, because it is capable of forming a thin film close to a single molecular layer, this Even if such a polymer is coated on the separation claw, particularly on the tip, the tip R does not increase, but exhibits lubricity and non-adhesion. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the polyarylenesal according to the present invention
The Fido resin, at ambient temperatures above 0.99 ° C., continuously available for example its mechanical strength as the fixing paper separating claw member, US off Irippusu Company RYTON (registered trademark)
Polyphenylene sulfide tree commercially available as
Fat, RE101JA manufactured by Asahi Glass Company, RFG1530 manufactured by the company
Synthetic resin such as JA . Next, the fluorinated polyether polymer having at least one polar end group used in the present invention comprises -C _X1 F _2X1 -O- units (where X ₁ is 1 to 4).
Is the main structural unit, and the number average molecular weight is about 1000
~ 5000 polymers, for example: And particularly preferably, A fluorinated polyether polymer having an average molecular weight of about 2000, which is commercially available under the trademark Fomblin Z-DISOC (registered trademark of Montenson, Italy) represented by the following formula: ## STR5 ## A fluorinated polyether polymer having an average molecular weight of about 2,000 and sold under the trademark Fomblin Z-DEAL (registered trademark of Montenson, Italy) represented by the following formula: ## STR6 ## And a fluorinated polyether polymer having an average molecular weight of about 2000 and sold under the trademark Fomblin Z-DOL of Montenson, Italy. The viscosity of the fluorinated polyether polymer is too high to form a thin film of the fluorinated polyether polymer in order to impart lubricity and non-adhesiveness to the separation claw for a copying machine. For example, Fomblin Z-DOL2
000 at 20 ° C. is about 80 cst and Fomb
The viscosity of lin Z-DEAL2000 at 20 ° C.
0 cst. The fluorinated polyether polymer may be dissolved in a highly fluorinated organic solvent such as Freon 113 and applied by an appropriate method, for example, by a spray method or a dipping method, but the dipping method is preferable. This is because the yield of the coating liquid is very good. The concentration of the fluorinated polyether polymer dissolved in the highly fluorinated organic solvent is not particularly limited. However, considering the cost, it is preferably about 0.3 to 10% by weight, and a particularly effective thin film is obtained. For this purpose, the content is preferably about 0.5 to 3% by weight. Further, after painting and drying, the surface is polished with a soft cloth or tissue paper or the like, and the slightly cloudy surface state is made glossy. This is to remove excess fluorinated polyether polymer. Since the film formed on the surface of the separation nail is very thin, it is difficult to measure the film thickness. Since the monomolecular layer of the fluorinated polyether polymer applied to the present invention is considered to be about 40 angstroms, it is considered that this coating has a thickness close to that and is at most 1 μm or less. Films that are too thick will contain excess fluorinated polyether and, as a result, will have many free reactive end groups that are not involved in binding to the separating nail resin matrix. This adversely affects the lubricity and non-adhesion required for the separating claw for a copying machine of the present invention. The above-mentioned method, that is, a fluorinated polyether polymer is dissolved at a suitable concentration in a highly fluorinated organic solvent on a separation nail base resin, and a film is formed by a suitable coating method such as dipping. Dry at an appropriate temperature, for example, in a hot air (50 ° C.) drying oven to remove the fluorinated organic solvent. The treatment may be carried out at a higher temperature after the drying or for the purpose of the drying, and it is preferable in view of the possibility of increasing the reactivity between the polar terminal group of the fluorinated polyether and the resin of the separated nail matrix. For example, this fluorinated polyether polymer-containing solution is applied by dipping to the surface of a base material obtained by injection molding TORLON, which is an aromatic polyamide-imide resin of Amoco Co., USA. 25
Heat treatment at a high temperature of 0 to 270 ° C. for an appropriate time. Here, the high temperature refers to a temperature at which the base resin and the fluorinated polyether do not thermally deform or thermally decompose. Examples and comparative examples are shown below, and the mixing ratios of the raw materials are all represented by weight%. Separate toe
The radius of curvature of the end (tip R) is 0.1 mm or less, preferably
It is 0.05 mm or less. Reference Examples 1-3: 10% graphite, polyetherimide resin (ULTEM 1000, manufactured by General Electric Company, USA) 3
0% and polyamide-imide resin (Amoco
(RLON 4000T) 60% was mixed with a Henschel mixer, kneaded and extruded with a twin screw extruder, and the strand was cut to obtain pellets. This pellet was injection molded to obtain a molded product having a shape of a separated claw and a friction test piece. As the fluorinated polyether polymer, the following three types of products (the number average molecular weight was 2,000) were selected from the following Montedoson, Italy. That is, in Reference Example 1, Fomblin Z-DISOC In Reference Example 2, Fomblin
Z-DEAL Further, in Reference Example 3, Fombl
in Z-DOL Each of the fluorinated polyether polymers is immersed in a Freon 113 solution in which 1.5% of each is dissolved, and is applied to at least the paper passing surface at the leading end of the separation claw. After drying and heat treatment at 24 ° C for 24 hours,
The lubricity, non-adhesiveness, and functionality as a separation nail material were evaluated. The method of each evaluation is as follows. Lubricity: Using a thrust type friction tester, load 1 kg / c
The bearing steel (SUJ2) was tested under the conditions of m ² and a speed of 1 cm / sec. Non-adhesiveness: A contact angle with water and acetic acid was determined using a goniometer-type contact angle tester manufactured by Elma Optical Co., Ltd. using the separation nail as a test piece. Functionality as Separating Claw: Using a dry copying machine Z-60 manufactured by Sharp Corporation, a test piece having the same shape as the separating claw of the same type was attached in a fixed position, and 50,000 sheets of A4 size copy paper were passed continuously. Paper and repeat 50,000 times,
Number of copies at the time of paper separation failure (paper jam) from the fastening roller, presence / absence of toner image contamination due to claw marks, amount of toner attached to separation claw [No or small amount of toner attached ), A relatively small amount (marked with ○), a small amount (marked with Δ), and a large amount (marked with ×)]. Further, after the toner adhered to the separation nail after the paper passing test was wiped off with ethyl alcohol, the contact angles with water and acetic acid were measured. The results obtained are summarized in Table 1. [Table 1] Comparative Example 1 A test piece was obtained in exactly the same manner as in Reference Example 1, except that the coating film of the fluorinated polyether polymer was not formed on the surface of the separation nail, and the same measurement was carried out. Also shown in Table 1. As is clear from Table 1, the separation claws shown in Reference Examples 1 to 3 have good lubricating properties, and exhibit a contact angle comparable to that of a fluororesin alone, and are extremely excellent in non-adhesiveness. Thus, the practical functions of the copying machine were satisfactory. The contact angle of the sheet passing surface after or test also showed a large value of as before the test, there was a big difference between the contact angle of Comparative Example 1. This indicates that the fluorinated polyether polymer film was still present on the separation nail surfaces of Reference Examples 1 to 3 even after the test, and the fluorinated polyether polymer film of the present invention had good adhesion strength and abrasion resistance. It can be seen that it has the property. Examples 1 and 2 and Reference Examples 4 to 7 As a heat-resistant resin for separating nails, Example 1 was made of polyphenylene.
RE101JA made by Asahi Glass Co., Ltd.
Example 2 is polyphenylene sulfur
Asahi Glass RFG1530JA (15%
Reference Example 4 is an aromatic polyamide-imide resin, Torlon 4203 (3% titanium dioxide, 0.5%) manufactured by Amoco, USA.
%, Containing a polytetrafluoroethylene resin), and Reference Example 5 is Torlon, an aromatic polyamide-imide resin manufactured by Amoco, USA.
4301 (12% graphite, 3% ethylene tetrafluoride resin) , Reference Example 6 is a polystyrene ketone resin, PEEK-150P manufactured by ICI of the United Kingdom, and Tismo, a potassium titanate whisker manufactured by Otsuka Chemical Co., Ltd. D
101 30% melt blended, Reference Example 7 is an aromatic polyimide resin Vespe manufactured by DuPont, USA
1 SP-1 was used. Then, the molding method is the same as in Example 1,
2 and Reference Examples 4 to 6 were injection-molded in the same manner as Reference Example 1. In Reference Examples 4 and 5, the molded product was further heat-treated at 260 ° C. for 24 hours, and Reference Example 7 was cut out from a round bar. A molded test piece was obtained.
The same fluorinated polyether as in Reference Example 1 in these molded articles, except that the heat treatment after coating was performed in a hot air drying oven at 50 ° C., all coated in the same manner separated nail surface as in Reference Example 1, subjected to various tests Was. Table 2 summarizes the results. [Table 2] As is clear from Table 2, the separation claws shown in Examples 1 and 2 have very good lubricity, non-adhesiveness, and practical functions, similarly to the separation claws shown in Reference Examples 1 to 3. The value was shown. Further, from the result of the contact angle after passing the paper, satisfactory results were obtained in both the adhesion strength and the wear resistance of the coating. [0054] Comparative Example 2-8: as a separation claw for the heat-resistant resin, Comparative Examples 2, 3 and 8 participation
The same Torlon4203 as considered Example 4, Comparative Example 4 is an aromatic polyamide-imide resin U.S. Amoco Corp. Torl
on 4347 (12% graphite, 8% ethylene tetrafluoride resin), Comparative Example 5 was the same as that of Example 1 in RE101.
Comparative Example 6 was the same as REG1530JA in Example 2.
In Comparative Example 7, the same PEEK-150P and Teismo D101A as in Reference Example 6 were melt-blended at a weight ratio of 7: 3. These resins were injection-molded in the same manner as in Example 1, and Comparative Examples 2, 3, 4 and 8 were heat-treated at 260 ° C. for 24 hours after molding. Furthermore, Comparative Examples 3 and 5 are polyfluorocarbon tough coat enamel TC7105G manufactured by Daikin Industries, which is a fluororesin-containing resin enamel.
N and TC-7409BK were uniformly coated with a suction type spray gun to a film thickness of about 30 μm.
After drying at 00 ° C. for 30 minutes, Comparative Example 3, ie, TC7
105GN was heat-treated at 250 ° C. for 30 minutes, and Comparative Example 5, ie, TC7409BK, was heat-treated at 180 ° C. for 30 minutes. In Comparative Example 8, after heat treatment, FomblinZ-25 (manufactured by Inokuchi Montezeson Co., Ltd., a fluorinated polyether polymer having no polar group at the terminal (viscosity 25c at 20 ° C.)
St) was immersed in a solution in which 1.5% was dissolved in Freon R113, taken out, and dried at 50 ° C. The same test as in Example 1 was performed using these test pieces, and the results are shown in Table 3. [Table 3] As is clear from Table 3, the nails having no coating on the surface of the separated nails, ie, Comparative Examples 2, 4, 6 and 7, had poor lubricity and non-adhesiveness, and showed good results in the actual machine test. Could not be obtained. In addition, even if the coating is formed on the nail surface, 30
The increase in the tip R due to the thick film of μm causes poor separation due to insufficient lubricating properties, causes nail marks due to insufficient non-adhesiveness, and increases the amount of adhered toner. Even when a thin film of a fluorinated polyether polymer is formed on the nail surface as in Comparative Example 8, the lubricating property and non-adhesiveness before the test are very good, but since there is no polar group at the end, coating is performed. The adhesion strength between the base material and the base material was poor, and peeling occurred during the paper passing test, resulting in a poor result.
This is judged by a large decrease in the contact angle after the test. [0059] [Effect] As apparent from the above, the copying machine according to the invention, lubricity thereof separating claw, by thinning the adhesion strength improving and coating the non-adhesive both excellent coating and the substrate It can withstand long-term continuous use without causing poor separation direction or paper jam due to the increase in the tip R of the separation claw tip, which is a drawback of the conventional coating technology, and without impairing thermal conductivity and electrical conductivity. What you get. Therefore, it can be said that the significance of the present invention is extremely large.

Claims (1)

( 1) A copier having a fixing roller whose surface is heated to 170 ° C. or higher, and a polyarylene sulfide resin separation claw for separating the fixing paper from the fixing roller. The tip of the separation claw should have a radius of curvature of 0.1 mm or less.
It is formed in a lower R shape, and at least a tip portion of the separation claw is formed .
A copying machine characterized in that the surface of the paper passing surface is coated with a fluorinated polyether polymer having the following chemical structural unit as a main structural unit . Embedded image (2) The copying machine according to claim 1, wherein the fluorinated polyether polymer is a fluorinated polyether polymer terminally bound with at least one polar group. (3) The fluorinated polyether polymer is a polymer having a number average molecular weight of 1,000 to 5,000.
A copier according to the item. (4) The copying machine according to claim 1, wherein the polyarylene sulfide resin is a polyarylene sulfide resin containing an inorganic filler. (5) The copying machine according to claim 1, wherein the polyarylene sulfide resin is a polyarylene sulfide resin containing a tetrafluoroethylene resin. (6) The copying machine according to claim 1, wherein the polyarylene sulfide resin is a polyphenylene sulfide resin. (7) The copying machine according to claim 1, wherein the copying machine is a dry copying machine.