JP3021573B2 - Paper feed roller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feed roller used for a reading device such as a facsimile. 2. Description of the Related Art A roller 10 as shown in FIG. 2 is used in a facsimile reading section. As shown in FIG. 3, the roller 10 is provided to send the transmission paper 11 to the reading device 13 and to read the paper 11 while maintaining the paper 11 at an accurate position. In order to execute accurate paper feeding and reading, the run-out of the roller must be highly accurate within a standard. If the value is out of the standard, a transmission failure such as a so-called white spot occurs due to a reading failure. If the surface of the roller 10 is not white, a signal having a sufficiently high contrast between light and dark cannot be obtained, which also causes transmission failure. Therefore, conventionally, the roller portion 14 is formed from a white thermoplastic resin molded body, and the shaft is made rigid by using the metal shaft 15 as a whole to maintain the transmission accuracy. However, since metal is used for the shaft 15, there is a problem that it is easily rusted, and furthermore, in order to maintain a run-out tolerance, cutting is required in post-processing, which raises a problem that manufacturing costs are increased. In order to solve this problem, it is conceivable that the entire roller including the shaft is integrally formed with only the white thermoplastic resin composition without using the metal shaft. [Problem to be Solved by the Invention] The roller integrally molded with the thermoplastic resin composition as described above passes the run-out standard in a single unit test, but when actually applied to a facsimile, it is warped by gravity. Due to distortion or creep at the time of assembling, the deflection becomes higher than the standard, resulting in poor reading. Further, post-processing is necessary after integral molding. Therefore, if the distance from the reading position to the sheet deviates from the standard due to the shake, for example, all the light and dark portions of the portion are read as bright portions, and a so-called white spot occurs on the facsimile receiving side, resulting in transmission failure. The present invention solves the above problems, and provides a white paper feed roller that does not cause a problematic deflection due to bending due to gravity, distortion or creep at the time of assembly even when actually applied to a reading device such as a facsimile. Aim. Configuration of the Invention [Means and Actions for Solving the Problems] The paper feed roller of the present invention is a paper feed roller for feeding paper to a reading device, comprising: 100 parts by weight of vinyl ester resin and / or unsaturated polyester resin; ~ 200 parts by weight, and molding shrinkage rate 1.1 based on 10 to 100 parts by weight of glass fiber
% And the entire body including the shaft is integrally molded with a thermosetting resin composition having a flexural modulus of 700 kgf / mm ² after molding.
As described above, the roll outer peripheral surface is white. As described above, as the main resin, either or both of a vinyl ester resin and an unsaturated polyester resin are used. The vinyl ester resin is a polyester having a side chain having a vinyl group with respect to the ester main chain. For example, there are diallyl phthalate type, triallyl isocyanurate type and the like. The unsaturated polyester resin is a polyester having an unsaturated bond in an ester main chain. For example, there are bisphenol A type, isophthalic acid type and the like. Titanium oxide is generally in the form of powder used as a pigment or a filler. The compounding amount is the above main resin 100
It is 20 to 200 parts by weight based on parts by weight. If the amount is less than 20 parts by weight, the whiteness of the roller deteriorates, resulting in poor reading,
If the amount exceeds the weight part, the roller becomes brittle, and the formability also decreases. As the glass fiber, one mixed with various resins as a fibrous filler is usually used. The compounding amount is 10 to 100 parts by weight based on 100 parts by weight of the main resin. If the amount is less than 10 parts by weight, the mechanical strength of the roller decreases and the run-out becomes an unacceptable value, and if it exceeds 100 parts by weight, the formability decreases. This compound is crosslinked by a heat treatment or the like at the time of molding or after molding, and exhibits thermosetting properties. This thermosetting increases the flexural modulus and reduces the grape properties. If the thermosetting property is insufficient only by the basic compounding, a curing agent or a crosslinking agent may be added separately. In addition, additives such as other resins, fillers, pigments, release agents, thickeners, plasticizers, antioxidants, antistatic agents, and the like may be added as necessary. However, during molding, the molding shrinkage
It must be 0.1% or less. This is to maintain the molding accuracy without performing post-processing. When the above-mentioned basic composition itself has a molding shrinkage rate exceeding 0.1%, a low shrinkage agent is added. As the low-shrinkage agent, vinyl acetate, saturated polyester, or the like is used, and its blending amount is preferably 5 to 20% by weight. As the properties of the finally formed roll, it is necessary that the flexural modulus is 700 kgf / mm ² or more and the outer peripheral surface of the roll is white. The reason why the flexural modulus is required to be 700 kgf / mm ² is to keep the deflection within a range in which there is no problem even if a stress or strain due to external stress or own weight occurs. The roll outer peripheral surface must be white for the reason described above. Flexural modulus is 700Kgf / mm ^{2 in the} basic formulation
If the above is not the case, the flexural modulus may be appropriately adjusted by the above-mentioned additives. The thermosetting resin generally has a low frictional resistance, but the surface of the roller may be further subjected to a surface treatment such as gel coating, silicon coating, or fluorine coating to further reduce the surface frictional resistance. Like this,
Paper feeding can be performed more smoothly. [Effects of the Invention] As described in detail above, since all the rollers are integrally formed of the thermosetting resin composition, rust does not occur and the roller can be made lightweight. Also, by having a low shrinkage rate, deformation after molding is suppressed,
Runout due to manufacturing is also reduced. In addition, since a thermosetting resin is used, it has a sufficient flexural modulus and creep resistance. In addition, since titanium oxide is used and a vinyl ester resin and / or an unsaturated polyester resin that are less discolored and deteriorated by light are used, white color can be maintained for a long period of time, and reading errors do not occur. Furthermore, because of the integral molding of thermosetting resin, the number of parts and the number of manufacturing steps are reduced compared to conventional products,
Finishing is possible by centerless polishing, and it is not necessary to use a cylindrical cutting machine as in the related art. EXAMPLES Hereinafter, preferred examples of the present invention will be described in detail.
The present invention is not limited to these embodiments, and can be implemented in various modes without departing from the gist.

Examples 1, 2 and 4 to 7 Into a kneader, a curing agent, a release agent, and a thickener were added together with the composition shown in Table 1 of the attached table, and the viscosity of the resin was further reduced during kneading to improve kneading properties. Was improved, styrene as a crosslinking agent at the time of curing was added, and the mixture was kneaded and then taken out in a sheet form. After aging this material in an atmosphere of 20 ° C for 48 hours,
A pre-formed product having a predetermined shape is formed, and the pre-formed product is pressed by a press mold at a mold temperature of 130 to 150 ° C. and a molding pressure of 20 to 100 kgf.
/ cm ² and a molding time of 2 to 5 minutes to obtain a roller shape shown in FIG. At this time, the molding shrinkage was measured. After deburring the roller 1, the outer periphery was trimmed with a centerless polishing machine. The flexural modulus and runout of the roller 1 were measured. Further, the roller 1 was set on a facsimile tester while being supported by the shaft 2, and a transmission test was performed to check the reading and paper feeding states. Here, the flexural modulus is the distance between spans based on JISK6911.
The run-out was measured at room temperature using an autograph at 100 mm and a laser micrometer at 60 revolutions per minute. Each measurement result is shown in Table 2 of the separate table.

Example 3 After the above-described measurement of the roller of Example 2 was completed, gel coating was performed to obtain Example 3. A test was performed on the third embodiment using a facsimile tester.

Comparative Examples 1 to 8 Rollers were molded in the same manner as in Examples 1, 2 and 4 to 7 according to the formulations shown in Table 1, and measurements were made. In Comparative Examples 7 and 8, injection molding was performed and finishing was performed by cutting instead of press molding and centerless polishing machine treatment. Table 2 shows the measurement results. In Comparative Examples 1 and 2, since the molding shrinkage of the material was large and the deformation during molding was large, the run-out after finishing was large, and transmission failure due to white spots occurred in a test using a facsimile tester. In Comparative Example 3, the rigidity of the material was low, the material was easily chipped at the time of molding, and the bending elastic modulus was low.
In Comparative Example 4, the whiteness was poor because the amount of titanium oxide was small,
Since the contrast between light and dark was low, transmission failure occurred.
In Comparative Example 5, the flowability of the material was poor due to the large amount of glass fiber, and the material could not be formed into a predetermined shape. Comparative Example 6
Then, white spots occur as in Comparative Examples 1 to 3, and
Prolonged exposure to the reading light caused discoloration. Comparative Example 7
Then, white spots occurred due to the occurrence of creep. Comparative Example 8
Although there is no problem in terms of function, post-processing is indispensable and the manufacturing cost has increased. In Table 1, unsaturated polyester resin and vinyl ester resin are manufactured by Showa Kogyo Co., Ltd., titanium oxide is manufactured by Ishihara Sangyo Co., glass fiber is manufactured by Asahi Fiber Glass Co., Ltd., vinyl acetate resin is manufactured by Nippon Synthetic Chemical Co., Ltd. Calcium is manufactured by Kyowa Chemical Co., Ltd., aluminum hydroxide is manufactured by Showa Denko KK, phenolic resin is manufactured by Asahi Organic Materials Co., Ltd., glass (30%) reinforced PB
T and polyacetal are manufactured by Asahi Kasei Corporation.

[Brief description of the drawings]

FIG. 1 is a partially cutaway view of one embodiment of the white paper feed roller of the present invention, FIG. 2 is a partially cutaway view of a conventional paper feed roller, and FIG.
The figure is an explanatory diagram of the reading state. 1 ... roller, 2 ... shaft

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI // C08L 63/10 C08L 63/10 67/06 67/06 (56) References JP-A-63-196436 (JP, A) Japanese Utility Model Showa 61-18258 (JP, U) Japanese Utility Model Showa 63-159457 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B65H 5/06 C08J 5/24 F16C 13/00 H04N 1/00 108

Claims (1)

(57) [Claims] 1. A paper feed roller for feeding a sheet to a reading device, wherein a basic composition comprises 100 parts by weight of vinyl ester resin and / or unsaturated polyester resin, 20 to 200 parts by weight of titanium oxide, and 10 to 100 parts by weight of glass fiber. Mold shrinkage 1.1%
A paper feed roller characterized in that the entire body including the shaft is integrally molded with the following thermosetting resin composition, the flexural modulus after molding is 700 kgf / mm ² or more, and the roll outer peripheral surface is white. .