JP2003080533A - Method for manufacturing foamed elastomer roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a foamed elastomer roller, which has an arbitrary uneven shape on its surface, suitable for an image forming apparatus. SOLUTION: In manufacturing the foamed elastomer roller by in-mold foaming, a roller, of which the surface is held to a shapable state before the curing of a foamed elastomer layer by heating is completed, is taken out of a foaming mold to be put in a shaping split mold of which the inner surface have an uneven shape or a wire is wound around the surface of the taken-out roller to further heating or heating and moistening the roller.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a foam elastic roller. More specifically, the present invention relates to a foamed elastic roller having a foamed elastic layer having an irregular surface, which is useful as a toner supply roller or the like used in an image forming apparatus. The present invention relates to an efficient manufacturing method.

[0002]

2. Description of the Related Art In an image forming apparatus such as a dry electrophotographic apparatus, rollers such as a toner supply roller, a developing roller, a transfer roller, a cleaning roller, and a paper feeding roller having a foamed elastic layer formed on the outer circumference of a rotary shaft. Is used. As a method for manufacturing these so-called foam elastic rollers, an integral foam molding method in which a foam-forming material is cast into a cylindrical foam mold in which a rotary shaft is set and foam-cured,
It is generally used because of its excellent productivity. On the other hand, the foamed elastic roller, especially the toner supply roller, is used to improve the toner transportability and scraping ability.
It is often required that the surface of the elastic foam layer has an uneven shape.

In response to such a demand, it may be considered that the inner surface of the foaming mold has a concavo-convex shape and that shape is formed on the surface of the foaming elastic body layer. A concave groove that linearly extends in the roll axis direction. Although a method of using a foaming mold having an inner surface of is also proposed, the shape is limited because the roller is extruded from the cylindrical foaming mold to demold, and any shape that meets the requirements is foamed. It could not be shaped on the surface of the elastic layer.

[0004]

Under such circumstances, the present invention provides a foamed elastic body roller having a foamed elastic body layer whose surface has an irregular shape by an integral foam molding method using a foam mold. It is an object of the present invention to provide a method for efficiently manufacturing.

[0005]

The inventors of the present invention have conducted extensive studies to achieve the above-mentioned object, and as a result, in manufacturing a foam elastic layer roller by in-mold foaming, the foam elastic layer is heated by heating. Before curing is completed, the roller is taken out from the foam mold in a state where the surface can be shaped, and then put in a split mold for shaping having an uneven inner surface, or after winding wire on the surface, further. The present invention is an invention of a method for manufacturing a foam elastic roller characterized by performing heating or heating and humidification.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In the method of the present invention, a foam roller having a rotary shaft and a foam elastic layer provided on the outer periphery of the rotary shaft and having an irregular shape on the surface is manufactured by an integral foam molding method. . The foam elastic layer in the foam roller is not particularly limited, and may be any of a polyurethane foam layer, a silicone rubber foam layer, an EPDM foam layer, etc., but especially for the toner supply roller, polyurethane is used. A foam layer (a roller provided with a polyurethane foam layer on the outer periphery of the rotating shaft is hereinafter referred to as a polyurethane foam roller) is preferable from the viewpoint of performance and the like. In the production of this polyurethane foam roller, a material containing a polyol component, a polyisocyanate component, a foaming agent and optionally a conductivity-imparting agent, a catalyst, a foam stabilizer, etc. is used as the polyurethane foam forming material. . In the polyurethane foam-forming material, the polyol component and the polyisocyanate component may be contained in the form of a prepolymer obtained by reacting them.

The polyol component used for producing the polyol or prepolymer is not particularly limited, and examples thereof include polyether polyol, polyester polyol, hydrophobic polyol and the like. Here, as the polyether polyol, a polyol obtained by addition-polymerizing ethylene oxide or propylene oxide to glycerin or the like, or a polyol such as polytetramethylene glycol, ethylene glycol, propanediol or butanediol is preferably used. As the polyester polyol, a condensed polyester polyol obtained by condensation of a dicarboxylic acid with a diol or triol, a lactone polyester polyol obtained by ring-opening polymerization of a lactone based on a diol or triol, or a terminating end of a polyether polyol is a lactone. A polyol such as an ester-modified polyol modified by ester modification is preferably used. As the hydrophobic polyol, polyisoprene polyol, polybutadiene polyol, hydrogenated polybutadiene polyol, etc. are used. These polyol components may be used alone or in combination of two or more.

On the other hand, as the polyisocyanate component used in the production of polyisocyanate or prepolymer, tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), crude diphenylmethane diisocyanate (crude MDI), isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate; Hydrogenated tolylene diisocyanate; polyisocyanates having no unsaturated bond such as hexamethylene diisocyanate, and their modified products with isocyanurate, carbodiimide, glycol and the like. These polyisocyanate components may be used alone or in combination of two or more.

Next, as the foaming agent, considering ease of handling in the manufacturing process, easiness of vaporization and foaming, and the like,
Generally, a physical foaming agent having a boiling point in the range of 20 to 60 ° C. is preferably used. When this foaming agent is used as a raw material for a polyurethane foam, the foaming agent alone has a low viscosity and it is difficult to obtain a stable flow rate in a foaming machine. It is advantageous. Examples of such a foaming agent include n-pentane, isopentane, cyclopentane, methylene chloride, Freon 134a (1,1,1,2-tetrafluoroethane), Freon 245fa (1,1,1,1).
3,3-pentafluoropropane), Freon 365mf
c (1,1,1,3,3-pentafluorobutane), Freon 356, Freon 141b (1,1-dichloro-1-)
Fluoroethane), Freon 142b (1-chloro-1,
1-difluoroethane), freon 22 (chlorodifluoromethane), and water. These may be used alone or in combination of two or more.

Next, in the polyurethane foam-forming material of the present invention, carbon black, an ionic conductive agent, etc. may be mentioned as the conductivity-imparting agent optionally used. Examples of carbon black include gas black such as electrified black, Ketjen black, and acetylene black, oil furnace black including ink black, thermal black, channel black, lamp black, and the like. As an ion conductive agent,
For example, tetraethylammonium, tetrabutylammonium, dodecyltrimethylammonium such as lauryltrimethylammonium, octadecyltrimethylammonium such as stearyltrimethylammonium,
Hexadecyltrimethylammonium, benzyltrimethylammonium, modified aliphatic dimethylethylammonium perchlorate, chlorate, hydrochloride, bromate, etc.
Ammonium salts such as iodates, borofluorides, sulfates, alkylsulfates, carboxylates and sulfonates; alkali metal or alkaline earth metal perchlorates such as lithium, sodium, calcium and magnesium. , Chlorate, hydrochloride, bromate, iodate, borofluoride, trifluoromethyl sulfate, sulfonate and the like.

These conductivity-imparting agents may be used alone or in combination of two or more. The compounding amount is not particularly limited and may be appropriately selected according to various situations, but is usually 0.1% by weight with respect to 100 parts by weight of the polymer material.
To 40 parts by weight, preferably 0.3 to 20 parts by weight. Further, a filler-based conductive agent such as a metal powder or a metal oxide powder can be added together with the above carbon black or ionic conductive agent. Further, in the polyurethane foam-forming material, examples of the catalyst optionally used include, for example, the organometallic catalysts dibutyltin dilaurate, dibutyltin diacetate, stannas octoate, dibutyltin marker butide, dibutyltin thiocarboxylate, dibutyltin dimaleate. Neat, dioctyltin mercurtide, dioctyltin thiocarboxylate, phenylmercury, silver propionate, tin octenoate, amine-catalyzed triethylamine, N, N, N'N'-tetramethylethylenediamine, triethylenediamine, N
-Methylmorpholine, dimethylaminoethanol, bis (2-dimethylaminoethyl) ether, 1,8-diazabicyclo (5,4,0) -undecene-7 and the like are preferably used. These catalysts may be used alone,
You may use it in combination of 2 or more type.

Further, in the polyurethane foam-forming material, examples of the foam stabilizers optionally used include polyether silicone oil, nonionic surfactants, ionic surfactants, etc. Alternatively, two or more kinds may be used in combination.
In the method of the present invention, as the foaming mold, a cylindrical mold made of resin, ceramics or metal is suitable. When a resin foam mold is used, a mold having resistance to the foam forming material cast into the mold is used. When the foam-forming material is the polyurethane foam-forming material, the resin-made foam mold is preferably a foam mold made of polypropylene, polyethylene, or the like. The foaming mold having the inner surface coated with the fluororesin has an effect of preventing the skin layer from remaining on the surface of the foamed elastic body, and can be suitably used in the method of the present invention. Examples of the rotary shaft include a metal member made by plating a steel material such as sulfur free-cutting steel with zinc or the like, or a metal member such as aluminum, stainless steel, or a magnesium alloy.

Next, a method of manufacturing the foam roller of the present invention will be described with reference to FIG. In the present invention, FIG. 1 shows a process in which a roller is taken out of a foaming mold, and then put in a split mold for shaping and further heated or heated and humidified to obtain a final product. It is sectional drawing in the surface orthogonal to. Is a roller taken out from the foam mold, 1 is a rotating shaft, and 2 is a foam elastic layer. This roller is put into a split mold for shaping which has an uneven inner surface composed of 3a and 3b as described above, and heating or heating and humidification are performed in this state. The roller can be easily taken out by opening the split mold, and as a result, a foamed elastic roller having an uneven shape on its surface can be obtained. The concavo-convex shape on the inner surface of the split mold for shaping can be any shape as required. FIG. 2 is a plan view showing an example of the foamed elastic body roller obtained by the method of the present invention, and can have various shapes such as (a), (b), (c) and (d).

To explain the state of FIG. 1,
First, after setting the rotary shaft in the foaming mold, a predetermined amount of the foam-forming material is cast, and foaming of the foam-forming material is started at a temperature of usually 15 to 110 ° C, preferably 20 to 100 ° C. Let After the voids in the mold are filled with the foam, heating is started. A chemical reaction occurs and curing begins with heating, and the roll is taken out from the foaming mold in the middle of the process to obtain the state shown in FIG. If the curing in the foaming mold proceeds too much, it will not be shaped even if it is put into a split mold and then heated. Therefore, when the surface can be shaped, the curing rate in the foaming mold is preferably 70%. It is necessary to take out the roller from the foaming mold in a state where it is about 95%. From the viewpoint of operability such as ease of demolding from the foaming mold, it is particularly preferable to take out from the foaming mold when the curing rate is 80 to 90%. The curing rate is JIS K
6400 is the ratio of the tensile strength measured based on 6400 to the tensile strength of the completely cured foam elastic layer, and the curing rate of the completely cured foam elastic layer is 100%. The heating temperature in the foam mold and split mold is
40 to 120 ° C is suitable. Further, when heating in the split mold, the reaction can be promoted by performing humidification at the same time.

[0015]

EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. Example 1 70 parts by weight of polyether polyol having an average molecular weight of 5000 and 3 functional groups, 30 parts by weight of a styrene graft type polymer polyol, triethylenediamine 0.
3 parts by weight, 0.2 parts by weight of N-methylmorpholine,
1.5 parts by weight of water, 1.5 parts by weight of silicone foam stabilizer and 50 parts by weight of TDI-80 / polymeric MDI.
A polyurethane foam-forming material was prepared by blending / 50 isocyanate in an amount to give an index of 105. In a free foaming experiment in a cup, which was separately performed, this polyurethane foam-forming material started foaming at a temperature of 25 ° C. for 10 seconds after stirring and injection, and completed foaming for 90 seconds. The density at that time was 0.10 g / ml. An iron rotating shaft (diameter: 6 m) was placed in a cylindrical stainless steel foaming mold having an inner diameter of 18 mm and a length of 250 mm.
m, length 260 mm) was set and 6.5 g of the above polyurethane foam-forming material was injected from a foaming machine and foamed at 25 ° C. for 90 seconds. Then start heating at 90 ℃,
When 10 minutes had passed, the roller was removed from the mold, immediately put into the split mold, and further heated at 100 ° C. for 20 minutes. The curing rate of the foamed elastic body at the time of releasing from the foaming mold is 88%, and the inner surface of the split mold has a height of 300 μm and a height of 150 μm.
A large number of ridge grooves having a pitch in the roll axis direction of 0 μm are formed. When the splitting method was opened and the roller was taken out, a polyurethane foam elastic body roller with a shaft having a concavo-convex shape as shown in FIG. 2 (b) on the surface was obtained. This foamed elastic roller was suitable for an image forming apparatus.

Example 2 The foam elasticity obtained was obtained in the same manner as in Example 1 except that the demolded roller was placed in a split mold and then heated at 50 ° C. for 10 minutes under humidification of 85% humidity. The body roller was suitable for the image forming apparatus.

[0017]

By using the roller mold of the present invention and the roller mold produced by the method of the present invention, it is possible to produce a foamed elastic roller suitable for an image forming apparatus and having an irregular shape on the surface. it can.

[Brief description of drawings]

FIG. 1 is a roll showing a process of obtaining a final product by taking out a roller from a foaming mold, putting it in a split mold for shaping, and further heating or heating and humidifying in the method of the present invention. It is sectional drawing in the surface orthogonal to an axial direction.

FIG. 2 is a plan view showing an example of a foamed elastic roller obtained by the method of the present invention.

[Explanation of symbols]

1 rotation axis 2 Foamed elastic layer 3a, 3b Split mold for shaping

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B29K 105: 04 B29K 105: 04 B29L 31:32 B29L 31:32 F term (reference) 2H077 AC04 FA13 FA22 FA25 3J103 AA02 AA12 AA61 BA41 CA03 EA02 EA11 FA15 GA02 GA57 HA03 HA12 HA48 4F204 AA42 AD03 AG05 AG20 AH04 AR06 AR20 EA01 EB01 EF01 EF05 EK13 EK17 EK24 EK25 EL04

Claims (7)

[Claims] 1. A roller having an elastic foam layer provided on the outer periphery of a rotary shaft by a method in which a rotary shaft is set in a foam metal mold, a foam forming material is cast to foam and then heated and cured. In manufacturing, the roller is taken out of the foam mold in a state in which the surface can be shaped before the curing of the elastic foam layer by heating is completed, and is put in a split mold for shaping having an uneven inner surface. A method for manufacturing a foamed elastic roller, further comprising heating or heating and humidifying. 2. A roller in which a foam elastic layer is provided on the outer periphery of the rotary shaft by a method in which a rotary shaft is set in a foam mold, a foam forming material is cast to foam and then heated and cured. In the production of, before the curing of the elastic foam layer by heating is completed, the roller is taken out from the foam mold in a state where the surface can be shaped, and after the wire is wound around the surface, further heating or heating and humidification are performed. A method for manufacturing a foamed elastic roller, comprising: 3. The curing rate of the elastic foam layer (JIS K 6
It is the ratio of the tensile strength measured based on 400 to the tensile strength of the completely cured elastic foam layer, and the curing rate of the completely cured elastic foam layer is 100%. 3. The method for producing a foamed elastic roller according to claim 1, wherein the foamed elastic roller is taken out from the foaming mold with 70% to 95%. 4. The method for producing a foam elastic roller according to claim 3, wherein the foam elastic layer is taken out from the foam mold in a state where the curing rate is 80 to 90%. 5. Heating at a temperature of 40 to 120 ° C. or temperature of 30
The method for producing a foamed elastic roller according to claim 1 or 2, wherein heating is performed at -60 ° C and humidification is performed at a humidity of 80-95%. 6. The method for producing a foam elastic roller according to claim 1, wherein the foam elastic layer is a polyurethane foam layer. 7. The method for manufacturing an elastic foam roller according to claim 1, wherein the elastic foam roller is a toner supply roller.