JP4634205B2 - Blade manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a blade used in an electrophotographic apparatus or the like.

  In general, an electrophotographic apparatus supports a cleaning blade for removing toner remaining on a photosensitive member after transfer to a recording sheet, and a developing blade for forming a thin film while frictionally charging toner in a developing device. A blade having an elastic member joined to the body is provided.

  The cleaning blade is formed by integrating a metal holder for attaching the blade to the electrophotographic apparatus and a blade member of an elastic member at one end of the holder, and the blade member is excellent in wear resistance, permanent distortion, etc. Therefore, polyurethane elastomer is usually used.

  By the way, a cleaning blade having such a polyurethane blade member is conventionally manufactured by performing a cast molding operation using a polyurethane-forming material. In other words, a cleaning blade mold composed of an upper mold and a lower mold was prepared, with a holder coated with adhesive on one end in the short direction, with the adhesive coated part of the holder protruding into the mold cavity. By injecting a liquid composition containing a prepolymer partially polymerized with a polyisocyanate and a polyol and a curing agent into the mold, allowing it to undergo a curing reaction, and then demolding the cured product. A cleaning blade can be manufactured.

  Moreover, in order to raise production efficiency, it manufactures also with the following methods. Two holders coated with an adhesive on one end are placed opposite to each other with the adhesive coated part of the holder protruding in the mold cavity, and the polyisocyanate and polyol are partially placed in the mold. A liquid composition containing a polymerized prepolymer and a curing agent is poured, and a curing reaction is performed to obtain a molded product in which two holders are integrated with a polyurethane elastomer. Then, the urethane part of the molded product is cut into two parts, and two cleaning blades can be manufactured by cutting and removing unnecessary parts of the urethane part along both ends in the holder longitudinal direction. it can.

  However, since the curing reaction is performed at 120 to 150 ° C., distortion due to heat shrinkage remains. At this time, since the polyurethane elastomer has a larger amount of heat shrinkage than the holder made of metal, the portion bonded to the holder is fixed to the metal holder with a small amount of heat shrinkage even if trying to shrink. Is suppressed, but the portion not fixed to the holder contracts greatly.

  For this reason, the blade after cutting is shrunk from the end in the longitudinal direction of the blade toward the center, and the vicinity of both ends is jumped up, and the blade member (reference numeral 3 in FIG. ) To the edge A (5 in FIG. 1) is not constant in the longitudinal direction, and both ends are long.

  When such a cleaning blade is pressed against the photosensitive drum, the blade nip width varies in the longitudinal direction of the cleaning blade, resulting in a problem that uniform cleaning properties cannot be obtained. In particular, recently, since the diameter of the toner has been reduced along with the full color of the laser beam printer, a cleaning blade having a highly accurate edge position in the longitudinal direction of the blade member is required. Moreover, since the distance A is long at both ends in the blade longitudinal direction, the blade is more strongly pressed against the drum.

  In order to solve such a problem, a method of notching at both ends in the longitudinal direction of the urethane joint portion of the holder and a method of tapering from the center to the end have been proposed (for example, Patent Document 1).

However, in this method, since the shape of the holder is complicated, it is difficult to manufacture the holder with high accuracy. As a result, there is a problem in that the dimensional accuracy of the blade is lowered or the cost is increased.
Japanese Patent Laid-Open No. 11-194689

  An object of the present invention is to provide a method of manufacturing a blade for an electrophotographic apparatus or the like having a high dimensional accuracy when two blades are manufactured simultaneously.

  The present invention achieves the object by the following means.

According to a first aspect of the present invention, two holders are arranged so as to face each other, and then a blade-forming member is formed from a thermosetting resin over the two holders. and to produce a molded article made of the blade fabrication member and then divided into two by cutting the blade fabrication member, a manufacturing method of an electrophotographic apparatus for a blade to obtain two blades consisting of the holder and the blade member Cutting the blade-producing member from the perpendicular to the cutting line passing through the cutting line direction tip of the thermosetting resin bonding part of one holder, and the cutting line direction of the thermosetting resin bonding part of the other holder tip is offset, for an electrophotographic apparatus blade and performing in our extended blade fabrication member in between the two holders to the cutting line vertically It is a manufacturing method.

2nd invention which concerns on this application performs this cutting | disconnection in the state which extended the member for blade preparation between these two holders by 0.3%-4.0% of cutting line perpendicular direction by elongation rate. This is a method for producing the above-described blade for an electrophotographic apparatus .

A third invention according to the present application is the case where the distance between the two holders is 13 mm to 20 mm in the second invention, and the blade producing member is extended in the direction perpendicular to the cutting line at the time of the cutting. In the method for producing a blade for an electrophotographic apparatus , the elongation of the member for producing a blade is from 0.05 mm to 0.50 mm in elongation.

According to a fourth aspect of the present invention, in the above-described electrophotographic apparatus blade, the amount of deviation of the tip in the cutting line direction in the thermosetting resin joint portion between the two holders is 3 mm to 100 mm. Is the method.

A fifth invention according to the present application is the above-described method for manufacturing a blade for an electrophotographic apparatus , wherein the thermosetting resin is a polyurethane elastomer.

  According to the present invention, it is possible to manufacture a blade for an electrophotographic apparatus having good dimensional accuracy with high production efficiency.

  The present invention is described in detail below.

  As shown in FIG. 1, the blade manufactured according to the present invention has a blade member 3 joined to a holder 2 for attaching the blade 1 to an electrophotographic apparatus or the like. The material of the blade member is a thermosetting resin such as polyurethane or silicone resin, and when used as a cleaning blade, a polyurethane elastomer excellent in wear resistance, permanent deformation, etc. is preferable. The material of the holder is not particularly limited as long as it is generally used for a blade for an electrophotographic apparatus, and examples thereof include a highly rigid steel plate, a stainless steel plate, a galvanized chromate coated steel plate, and a chromium-free steel plate.

  For example, as shown in FIG. 2, a cleaning blade whose blade member is made of polyurethane elastomer can be manufactured by the following method. A cleaning blade mold composed of an upper mold and a lower mold is prepared, an adhesive is applied to one end of the holder 2 in the short direction, and this is placed in a cavity for forming a blade member of the mold (mold). Two parts are arranged to face each other in a protruding state, a liquid composition containing a prepolymer and a curing agent is injected into the mold, and this is subjected to a curing reaction at 120 ° C. to 150 ° C. A molded product in which the book is integrated with polyurethane elastomer is obtained.

  The two holders are arranged such that the cutting line direction front end 6 in the urethane joint portion of the other holder 2 is shifted from the perpendicular line 8 to the cutting line 7 passing through the cutting line direction front end 6 in the urethane joint portion of one holder 2. To do.

  The displacement is preferably 3 mm to 100 mm, and if it is less than 3 mm, the accuracy of the distance A (5 in FIG. 1: distance from the holder reference line (4 in FIG. 1) to the edge of the blade member) is improved over the entire edge. However, if the thickness exceeds 100 mm, an unnecessary portion at both ends of the urethane portion in the longitudinal direction that cannot be used as a product increases, and the mold becomes too large. Here, the “holder reference line” refers to a line that is a fixed distance from the short-side end (longitudinal edge) of the rectangular holder and serves as a reference for measuring the dimensions of the blade.

  As shown in FIG. 3, the cutting line direction tip 6 in the urethane joint portion of the other holder 2 passes through the cutting line direction tip 6 in the urethane joint portion of one holder 2 and is perpendicular to the cutting line 7 (not shown). When there is, the shrinkage of the urethane part of the molded product in which the two holders are integrated by the polyurethane elastomer is shrunk from both ends toward the center in the blade longitudinal direction.

  On the other hand, as shown in FIG. 2, by shifting the tip position of the holder, the environment of the end in the longitudinal direction of the opposing holder changes, and the direction of contraction of the end in the blade longitudinal direction is dispersed. It seems that the jumping up near both ends of the holder in the longitudinal direction is reduced.

  Then, the two blade holders and urethane integrally formed blade production member 3 'are cut substantially at the center by running a metal blade or the like from the end in the cutting line direction to the opposite end. Two cleaning blades can be manufactured by separating and further cutting away unnecessary portions of the blade member along both longitudinal ends of the holder.

  The cutting of the integrally formed product made of two holders and urethane is performed in a state in which the blade forming member 3 'between the two holders is extended in the direction perpendicular to the cutting line. At this time, the elongation of the blade forming member between the two holders is preferably 0.3% to 4.0% in terms of elongation. When the distance between the two holders is about 13 mm to 20 mm, the elongation is preferably about 0.05 mm to 0.50 mm.

  The two holders are arranged such that the cutting line direction front end 6 in the urethane joint portion of the other holder 2 is shifted from the perpendicular line 8 to the cutting line 7 passing through the cutting line direction front end 6 in the urethane joint portion of one holder 2. is doing. For this reason, in the two holders which oppose, the distance from the front-end | tip of a cutting line direction of the blade preparation member 3 'to the front-end | tip of a holder differs.

  Therefore, when the blade passes the front end in the cutting line direction of the blade manufacturing member 3 ′, the distance is longer, that is, the side of the blade manufacturing member that is out of the longitudinal end of the holder is deformed, resulting in a result. As described above, after cutting, the distance A between the blades on the side where the blade preparation member is large is long, and the distance A between the blades on the opposite side is short.

  However, when cutting with the blade production member 3 ′ between the two holders extended, the portion where the holder at the end in the cutting line direction is only on one side is the blade production member only on the side where the holder is located, that is, Since the blade manufacturing member is pulled to the opposite side of deformation at the time of cutting, the accuracy of the distance A of the blade after cutting can be improved as a result.

  If it is less than 0.3%, this effect is small, and if it exceeds 4.0%, the urethane is biased to the side where the holder is located more than the deformation of the blade producing member 3 ′ at the time of cutting. The distance A of the blade on the side where there is a large amount is short, and the distance A of the blade on the opposite side becomes long, which is not preferable. Moreover, when it extends beyond 4.0%, it will not be cut with a blade but will be in a state of tearing from where the blade enters, so the cut surface becomes rough, which is not preferable.

  The integrally molded product may be fixed as long as it can be fixed so that the blade does not move when cutting the blade-producing member 3 ′. For example, a pin is inserted in advance on the surface on which the integrally molded product is placed, and the formed product is formed in the holder. Alternatively, the notch may be fixed by inserting the pin into the pin, or by inserting the pin through a hole formed in advance in the holder.

  Examples of the polyurethane elastomer forming the blade member include a mixture of a polyisocyanate, a prepolymer composed of a polyol and a curing agent composed of a polyol, a chain extender, and a catalyst.

  Examples of the polyisocyanate include 4,4′-diphenylmethane diisocyanate (MDI), 2,4-tolylene diisocyanate (2,4-TDI), 2,6-tolylene diisocyanate (2,6-TDI), and xylene diisocyanate. (XDI), 1,5-naphthylene diisocyanate (1,5-NDI), p-phenylene diisocyanate (PPDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), 4,4′-dicyclohexylmethane diisocyanate (water) And MDI), tetramethylxylene diisocyanate (TMXDI), carbodiimide-modified MDI, polymethylenephenyl polyisocyanate (PAPI), and the like. Among these, it is preferable to use MDI.

  Examples of the polyol include polyester polyols, polyether polyols, caprolactone ester polyols, polycarbonate ester polyols, silicone polyols, and the like, and the number average molecular weight is preferably 1500 to 5000. That is, if it is less than 1500, the physical properties of the resulting urethane rubber tend to be lowered, and if it exceeds 5000, the viscosity of the prepolymer tends to increase and handling tends to be difficult.

  As the chain extender, for example, glycol is used. Examples of such glycol include ethylene glycol (EG), diethylene glycol (DEG), propylene glycol (PG), dipropylene glycol (DPG), and 1,4-butanediol. (1,4-BD), 1,6-hexanediol (1,6-HD), 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, xylylene glycol (terephthalyl alcohol), triethylene glycol, etc. Is mentioned. In addition to the above glycols, polyhydric alcohols are used, and examples of such polyhydric alcohols include trimethylolpropane, glycerin, pentaerythritol, sorbitol, and the like.

  As the catalyst used as the curing agent, a commonly used polyurethane curing catalyst can be used, and examples thereof include a tertiary amine catalyst. Trialkylamines such as triethylamine, tetraalkyldiamines such as N, N, N ′, N′-tetramethyl-1,3-butanediamine, aminoalcohols such as dimethylethanolamine, triethylenediamine, piperazine, triazine, 4 Examples include organic acid salts and phenol salts of secondary amines. Further, organic acid salts of metals such as potassium acetate and potassium octylate alkali may be used. Moreover, the metal catalyst normally used for urethane may be sufficient and a dibutyltin dilaurate etc. can be illustrated. These may be used alone or in combination.

  If necessary, additives such as catalysts, pigments, plasticizers, waterproofing agents, antioxidants, ultraviolet absorbers and light stabilizers other than those described above can be blended in the curing agent.

  The polyurethane elastomer of the blade member used in the present invention can be produced according to a conventional method using the above materials. Specifically, it can be produced according to a prepolymer method, a semi one-shot method, or a one-shot method.

  The adhesive that can be used in the present invention may be a general polyurethane-metal adhesive, and examples thereof include phenol-based and urethane-based adhesives.

  EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[Example 1]
(Preparation of thermosetting polyurethane raw material)
94.3 g of a prepolymer having an NCO% of 7.0% using 4,4′-diphenylmethane diisocyanate as the isocyanate and an adipate polyester polyol having a number average molecular weight of 2000 as the polyol, 1,4-butanediol and tri 5.7 g of a curing agent was prepared by adding 1000 ppm of P15 manufactured by Air Products Japan and 3000 ppm of triethylenediamine (TEDA) to a mixture having a mass ratio of methylolpropane of 65:35.

(Forming a cleaning blade)
A cleaning blade mold composed of an upper mold and a lower mold and a holder having a length of 240 mm and a width of 25 mm are prepared. A phenolic adhesive is applied to one end of the holder in the short direction, and the mold (mold) In the cavity for forming the blade part, two of these parts are arranged facing each other in a protruding state. At this time, with the inlet side facing up and the edge surface of the edge facing forward, the left holder is (1) and the right holder is (2). Two holders are arranged so that the tip in the linear direction (inlet side (9 in FIG. 2)) is 10 mm inward from the tip in the cutting line direction where the urethane of the holder (2) is joined. did. A liquid composition containing a prepolymer and a curing agent is poured into this mold, and this is cured at 120 ° C. to 150 ° C., and the two holders are integrated with a polyurethane elastomer. A molded product having a distance of 15 mm was obtained. Then, by pulling the integrally molded product in the direction perpendicular to the cutting line and extending the blade manufacturing member 3 ′ between the two holders by 1.0%, a cutter is inserted from the inlet side and cut. Separately, the unnecessary portions of the blade member were cut and removed along the longitudinal ends of the holder to obtain two cleaning blades (1) and (2).

(Measurement of edge position)
As shown in FIG. 4, the distance A (5 in FIG. 4) of the blades 3 at the longitudinal ends 10 and 11 of the blade member 3 and the center 12 of the obtained cleaning blades (1) and (2) is measured. The difference of the distance A between the longitudinal direction both ends and the center of the blade was determined. If the difference is 30 μm or less at both ends of the blade, ◎, if one is 31 to 50 μm, ○, if one is 51 μm or more, ×.

[Example 2]
This was performed in the same manner as in Example 1 except that the blade producing member 3 ′ was cut in a state of being extended by 2.0%.

[Example 3]
This was performed in the same manner as in Example 1 except that the blade producing member 3 ′ was cut in a state of being stretched by 3.0%.

[Example 4]
The same procedure as in Example 1 was performed except that the blade-producing member 3 ′ was cut in a state where it was stretched by 0.05%.

[Example 5]
This was performed in the same manner as in Example 1 except that the blade producing member 3 ′ was cut in a state of 4.0% elongation.

[Example 6]
Two so that the tip (inlet side) in the cutting line direction where the urethane of the holder (1) joins is 100 mm in side of the tip in the cutting line direction where the urethane of the holder (2) joins. The same procedure as in Example 1 was conducted except that the holder was arranged.

[Example 7]
Two so that the tip (inlet side) in the cutting line direction where the urethane of the holder (1) joins is 3 mm in the side of the cutting line direction where the urethane in the holder (2) joins. The same procedure as in Example 1 was conducted except that the holder was arranged.

[Comparative Example 1]
The same procedure as in Example 1 was performed except that the blade-producing member 3 ′ was cut without being stretched.

[Comparative Example 2]
The same procedure as in Example 1 was performed except that the tip (inlet side) in the cutting line direction where the urethane of the holder (1) joined was arranged at the same position as the tip of the holder (2).

  As can be seen from Table 1, in Examples 1 to 7, the difference between the left end and the right end and the center of the blade distance A is 50 μm or less. I understand. On the other hand, as can be seen from Table 2, in Comparative Examples 1 and 2, the difference between the center and both ends of the distance A is large at 51 μm or more, indicating that the accuracy is poor.

It is the schematic of the braid | blade for electrophotographic apparatuses manufactured by this invention. It is explanatory drawing which shows an example of the manufacturing method of the braid | blade which concerns on this invention. It is explanatory drawing which shows the manufacturing method of the conventional blade. It is explanatory drawing which shows the measurement position of the distance A in the braid | blade manufactured by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Blade for electrophotographic apparatus 2 Holder 3 Blade member 3 'Blade preparation member 4 Holder reference line 5 Distance A in blade
6 Cutting line direction tip 7 at the thermosetting resin joint portion of the holder 7 Cutting line 8 Perpendicular line 9 to the cutting line Inlet side 10 Left end of the blade member that is the measurement point of the distance A 11 12 Center of the blade member that is the measurement point of the distance A

Claims (5)

Two holders are arranged to face each other, and then a single blade-forming member is formed of thermosetting resin across the two holders, and the two holders and the blade-producing member are integrated. In a method of manufacturing a blade for an electrophotographic apparatus , in which a molded article is manufactured, and then the blade-forming member is cut into two parts by cutting to obtain two blades comprising a holder and a blade member. , The cutting line direction tip in the thermosetting resin joint part of the other holder is shifted from the perpendicular to the cutting line passing through the cutting line direction tip in the thermosetting resin joint part of one holder, the two A method for producing a blade for an electrophotographic apparatus , wherein the blade producing member between the holders is extended in a direction perpendicular to the cutting line. The cutting is performed in a state in which a blade forming member between the two holders is stretched in a direction perpendicular to the cutting line by 0.3% to 4.0% in elongation. A method for manufacturing a blade for an electrophotographic apparatus . In the case where the distance between the two holders is 13 mm to 20 mm, and the blade producing member is stretched in the direction perpendicular to the cutting line at the time of cutting , the elongation of the blade producing member is 0.05 mm in elongation. The method for producing a blade for an electrophotographic apparatus according to claim 2, wherein the blade is -0.50 mm. Electrophotographic apparatus for blade according to claim 1, the deviation amount of the cutting line forward end of the thermosetting resin bonding portion between the two holder characterized in that it is a 3mm~100mm Manufacturing method. Method of manufacturing an electrophotographic apparatus for blade according to claim 1, wherein the thermosetting resin is a polyurethane elastomer.

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