KR100863482B1 - Coating composition coating composition for rccycleing roller with transfer a roller of image reproducting device - Google Patents

Abstract

A coating composition for recycling the roller for toner transfer of an image reproduction equipment is provided to improve the lifetime of a toner cartridge by preventing the abrasion of the polymer film of a roller for toner transfer. A coating composition comprises 35 wt% of a diglycidyl ether-based epoxy resin having at least two oxirane groups obtained by the reaction of bisphenol A and epichlorohydrin; 20 wt% of m-phenylene diamine as a curing agent; 3 wt% of graphite or carbon black as a conductive carbon material; and 42 wt% of xylene as a diluting solvent for the uniform coating process.

Description

COATING COMPOSITION COATING COMPOSITION FOR RCCYCLEING ROLLER WITH TRANSFER A ROLLER OF IMAGE REPRODUCTING DEVICE}

The present invention relates to a coating composition for regenerating rollers for toner transfer of an image reproducing apparatus including a conductive carbon material, an epoxy resin, a curing agent, and a dilution solvent, which is excellent in wear resistance, friction resistance, and conductivity, and a roller regenerated using the same.

According to Kirk-Othmer, EnCyclopedia of Chemical Technology, Vol. 9, pp. 245-277 (4th edition, 1994), the main operating principles of image reproducing machines such as laser printers, copiers, fax machines, etc. It is divided into transfer and transfer stages. That is, ions are made on the surface of the photosensitive drum in the charging step, and the drum surface directly exposed to light in the light exposure step is neutralized by the moving component in the photosensitive layer. Toner is a thermoplastic pigment powder material that can be electrically charged and attracted to a magnetic field, and is stored in a part of a toner cartridge, commonly called a toner hopper, and then stored in a photoreactive drum by a toner conveying roller. It is transferred to a photoreactive drum and attached to the part of the image that is charged. Finally, these toners are transferred from a photosensitive drum to a print medium such as paper to reproduce an image.

In general, a toner conveying roller is used in the image reproducing apparatus described above, and is a device for conveying toner from a toner hopper to a photoreactive drum. The urethane foam is enclosed, and these polyurethane foams are filled with graphite or carbon powder so as to have suitable electrical properties. In the case of such a toner conveying roller, toner conveyance defects are caused by wear depending on use, thereby causing a serious defect in the image printer.

Looking at the prior art related to the present invention, first of all, in the case of a primary charged roller similar to the roller for toner transfer, most regeneration is performed by coating an appropriate conductive material on the polymer film to reduce the electrical resistance of the primary charged roller to its original state. U.S. Patent No. 5,823,929 discloses a method in which 23 nm size graphite or carbon black is mixed with a polymer binder such as polyurethane to make a dispersed state, and then the composition is coated with a worn primary charging roller with a thickness of 0.5 mm and regenerated. This technique has a limitation in obtaining a uniform and dense coating due to the low solubility of the graphite or carbon black in the dispersion solvent, there was a technical difficulty in maintaining a constant dispersion state at all times.

And the Republic of Korea Patent No. 10-0359731 proposed a coating using a polyhydroxy fullerene as a conductive material and a regeneration method using the same, but there is a disadvantage that the price is expensive and 1-methyl-2-pyrrolidinone and propylene glycol methyl ether acetate There was a disadvantage in that a large amount of a specific organic solvent, such as to use.

Therefore, it is possible to disperse electrically conductive particle materials such as graphite and carbon black, which are highly competitive in price, and to form a uniform and dense protective film on the polymer film, and to improve the wear resistance of the film. The coating composition of the toner conveying roller and the toner conveying roller to which the same is applied are desperately necessary settings.

In order to solve the problems of the prior art, the present invention provides a coating composition of a roller for toner transfer for an image reproducing apparatus comprising a carbon material, an epoxy resin, a curing agent, and a diluting solvent, which are graphite or carbon black having excellent electrical conductivity. Its purpose is.

It is another object of the present invention to provide a recycled toner conveying roller for an image reproducing apparatus and a method of manufacturing the same, by forming a uniform and dense protective film on the polymer film of the toner conveying roller using a coating composition to prevent the coating from abrasion. Is in.

Still another object of the present invention is to provide a toner cartridge including the toner conveying roller.

In order to achieve the above technical problem, the present invention

(a) 20 to 40% by weight of an epoxy resin;

(b) 10 to 20% by weight of curing agent;

(c) 0.5 to 5% by weight conductive carbon material, which is graphite or carbon black;

(d) A coating composition for regenerating rollers for toner transfer of an image reproducing apparatus, which is composed of a mixture of 35 to 69.5% by weight of a diluting solvent for uniform coating, is its main technical configuration.

In addition, the present invention is a composition of the present invention comprising a toner conveying roller regenerated by applying the coating composition to a toner conveying roller of the toner cartridge so as to have a dry film thickness of 1.0 to 5.0 µm, and a toner cartridge including the roller.

The present inventors confirmed that the coating composition composed of the above composition ratio is excellent in abrasion resistance, friction resistance and conductivity, and the primary charge roller and the roller for transporting toner coated with the same have a uniform and dense protective film to prevent wear of the film. On the basis of this, the present invention has been completed.

Hereinafter, the present invention will be described in more detail.

The epoxy resin is characterized by having at least two oxirane groups and is prepared by the reaction of epichlorohydrine (pipihydrhydrin) and a substance having two or more hydroxyl groups, bisphenol-A and epichlorohi are typical It is a diglycidyl ether type produced by the reaction of drin. Epoxy resin is used at 20 to 40% by weight of the total coating composition, when less than 20% by weight, the efficiency of fixing the conductive carbon material to the polymer film is lowered, and when it exceeds 40% by weight, the viscosity of the coating Since the increase does not form a uniform coating, the epoxy resin is preferably used in 20 to 40% by weight of the total coating composition.

The curing agent may be any compound capable of reacting with the oxirane group of the epoxy resin to crosslink. Specifically, the curing agent uses m-phenylene diamine including two or more amine groups. In the case of the curing agent is used in 10 to 20% by weight of the total coating composition, if it is out of the use range it does not form a uniform coating and the drying time is long, the curing agent is used in 10 to 20% by weight of the total coating composition It is desirable to.

The conductive carbon material, which is graphite or carbon black, is used in an image reproducing apparatus such as an antistatic agent or a printer or a copying machine due to its own electrical conductivity, and is used at 0.5 to 5% by weight of the entire coating composition. In this case, when the amount is less than 0.5% by weight, the conductivity is insufficient, and when it exceeds 5% by weight, it is difficult to form a uniform film, so the conductive carbon material is 0.5 to 5% by weight of the entire coating composition. It is preferable to use.

The dilution solvent is a uniform coating operation, there is no particular limitation as a solvent to disperse the epoxy resin and the curing agent, specifically, alcohols, ketones, ethers, hydrocarbon compounds can be used, preferably acetone or xyl Use Ren.

In order to recover the used toner roller which is recovered, worn or physically damaged, the surface of the roller is first washed with ethanol to remove foreign substances, and then 20 to 40 wt% of the epoxy resin, 10 to 20 wt% of the curing agent, graphite or The coating composition composed of 0.5 to 5% by weight of conductive carbon material, carbon black and 35 to 69.5% by weight of dilute solvent is selected from submerged coating, spray coating or gravure coating, so that the dry film thickness is 1.0 to 5.0 μm. It is made by drying at 10 ~ 100 ℃ after applying to the roller, if the dry film thickness after the drying is less than 1.0㎛ the desired level of conductivity and wear resistance can not be obtained, if it exceeds 5.0㎛, the film thickness at drying May be partially uneven, so the dry film thickness of the coating composition for roller regeneration is 1.0-5.0 μm. It is preferable to.

If the drying temperature is less than 10 ° C, the curing reaction of the resin is insufficient, so it is difficult to expect the effect of the coating film. If the drying temperature is higher than 100 ° C, the surface of the toner conveying roller may become uneven, so the drying temperature is 10 to 100 ° C. It is desirable to maintain.

In addition, a regeneration roller for transporting toner, which is regenerated using the coating composition for regeneration, may be attached to a toner cartridge.

As described above, using the coating composition for regeneration of the roller for toner transfer for an image reproducing apparatus according to the present invention, when the dry film thickness is maintained at 1.0 to 5.0 μm under a drying temperature of 10 to 100 ° C., the number of times of use is recovered A uniform and dense protective film is formed on the polymer film of the toner conveying roller which is worn, worn, or physically damaged, and thus the wear of the film is prevented, thereby effectively regenerating the roller.

Let us look at the specific details of the technical configuration through the embodiment. However, these embodiments are only examples for describing the present invention in more detail, but the protection scope of the present invention is not limited to the embodiments.

Examples 1 to 10 and Comparative Examples 1 to 7: manufacturing a coated toner conveying roller

Table 1: Recycled Toner Feed Rollers Applied  Physical properties of the film

division Additive (% by weight) Quality characteristic Epoxy resin Hardener Carbon black / graphite Electrical resistance Printer testing Wear resistance Example 1 30 15 0.5 ○ ○ ○ Example 2 30 15 One ○ ◎ ○ Example 3 20 10 2 ◎ ◎ ○ Example 4 40 20 3 ○ ◎ ○ Example 5 30 15 4 ◎ ◎ ○ Example 6 30 15 5 ◎ ◎ ◎ Example 7 35 20 3 ◎ ◎ ◎ Comparative Example 1 30 15 0 × × × Comparative Example 2 30 15 0.1 × △ × Comparative Example 3 10 5 One ○ △ △ Comparative Example 4 30 5 One ○ × × Comparative Example 5 10 10 One ○ △ △ Comparative Example 6 50 15 One △ × △ Comparative Example 7 30 30 One △ × △

(※ electrical resistance and abrasion resistance-◎: measured value / reference value = 10 or less, ○: measured value / reference value = 10 ~ 100, △: measured value / reference value = 100 ~ 1000, X: 1000 or more / printer test-◎: " Background (black background) "and" electrostatic ghosting ", △:" background "or some spots and streaks, X:" Background "and" electrostatic ghosting ")

According to the content shown in Table 1, epoxy resin (KE-300NS, KUMOH POLYMER), hardener (KH-700NS, KUMOH POLYMER), carbon black (40B2, Korea Carbon Black Co.) or graphite (crystalline vein graphite, Comex Carbon, Inc., a conductive carbon material and a diluting solvent were mixed to prepare a solution, and the solution was sufficiently mixed using an ultrasonic mill to prepare a coating solution.

After removing the toner conveying roller from the toner cartridge collected after use to remove all foreign matter on the surface with ethanol, the coating solution was prepared so that the dry film thickness is 5.0㎛ and dried at a temperature of 50 ℃.

The physical properties of the coating film applied to the recycled toner transfer roller were measured by the following method and the results are shown in Table 1 above.

Test Example 1: Electrical Resistance

Measure the electrical resistance value (Ω / sq.) Of the coated toner transfer roller using the surface resistance meter, and compare the electrical resistance value of the toner transfer roller comparative material separated from the unused toner cartridge as a reference value. The results are shown in Table 1 above. (The numerical values of the measured values / reference values were determined based on the ratio of these values.)

Test Example 2: Printer Test

The remanufactured toner cartridge (Samsung, ML800 toner cartridge) using the coated toner transfer roller was mounted on the original laser printer (Samsung, 68H laser printer), and 16,000 sheets were printed under the same conditions as the original product. And the appearance of the "electrostatic ghosting" phenomenon was evaluated, the results are shown in Table 1 above.

Test Example 3: Wear Resistance

After collecting the roller for transporting the toner from the toner cartridge after the printer test, the foreign material on the surface was removed, and the electrical resistance value was measured. same.

As shown in Table 1, when the coating composition was treated within the scope of the present invention, excellent physical properties were shown, but when the amount of the conductive carbon material was low or absent as in Comparative Examples 1 and 2, the recycled toner was transported. The intrinsic function of the roller did not become sufficient, resulting in a problem of blurred images or double images and streaks on the printed media. In Comparative Examples 3 to 5, when the addition amount of the epoxy resin and the curing agent was small, the coating was not firmly and tightly coated on the surface of the toner conveying roller, resulting in a defect of the printed material. It was evaluated that the surface electrical resistance value of the roller for increase was high. And in the case of Comparative Examples 6-7, when the epoxy resin and the hardening | curing agent are added excessively, the stability of a solution may fall and gelatinization may occur, or the amount of skin adhesion may be uneven and the printed matter defect might arise.

Examples 11 to 14 and Comparative Examples 8 to 9: dry coating thickness of the coating solution composition

Transfer the toner to a dry film thickness of 0.5, 1.0, 3.0, 5.0, and 6.0 µm in a coating solution composition prepared using 30% by weight of epoxy resin, 15% by weight of curing agent, 1% by weight of carbon black, and 54% by weight of acetone as diluent. After applying to the roller for the physical properties were measured in the same manner as the measurement method shown in Test Examples 1 to 3, the test results are shown in Table 2 below.

Table 2: On the recycled toner transfer roller Applied  Physical Properties According to Film Thickness

 division Dry film thickness (㎛) Quality characteristic Electrical resistance Printer testing Wear resistance Comparative Example 8 0.5 △ △ × Example 11 1.0 ○ ◎ △ Example 12 3.0 ◎ ◎ ○ Example 13 5.0 ◎ ◎ ◎ Comparative Example 9 6.0 ◎ × ◎

As shown in Table 2, when the dry film thickness was treated at 1.0 to 5.0 μm suggested by the present invention, the performance of the roller for transporting recycled toner was similar to that of the comparative material, but the film thickness was the same as that of Comparative Example 8. When too thin, the defect of the printed matter and the abrasion resistance of the surface of the roller for toner transfer were greatly reduced. When the film thickness was too thick as in Comparative Example 9, the abrasion resistance increased but the printed matter was poor.

Claims (5)

In the composition consisting of an epoxy resin, a curing agent, a conductive carbon material, a dilution solvent, 35% by weight of a diglycidyl ether type epoxy resin having at least two or more oxirane groups by reaction of bisphenol-A and epichlorohydrin, 20 weight% of m-phenylene diamine of the curing agent, 3 wt% conductive carbon material which is graphite or carbon black, A coating composition for roller recycling for toner transfer of an image reproducing apparatus, characterized in that the composition is composed of a mixture of 42% by weight of xylene of a diluting solvent for uniform coating. delete delete delete delete