JP3980389B2 - Method for producing seamless flexible endless metal sheet - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a seamless flexible endless metal sheet, an electrophotographic photoreceptor substrate comprising the metal sheet, and an electrophotographic photoreceptor using the same.
[0002]
[Prior art]
As electrophotographic photocopiers and printers have become smaller and lighter, flexible and seamless endless metal sheets have come to be used for electrophotographic photoreceptor substrates. It was.
By making the electrophotographic photosensitive member into a belt shape, it is possible to reduce the size and weight of a high-speed color copier and printer that require a conventional large-diameter aluminum drum base.
[0003]
The film thickness of the seamless flexible endless metal sheet used as the base of electrophotographic photoreceptors such as copying machines, facsimiles, printers, etc. is due to the need for high image quality for full color images. In order to keep the gap with the constant, it is indispensable that the variation of the gap with the developing unit is the minimum necessary.
For this purpose, the flatness of the seamless flexible endless metal sheet serving as the substrate must be as uniform as possible.
A seamless flexible endless metal sheet is usually produced by electroforming using an aqueous solution containing nickel sulfamate.
[0004]
In this method, a constant voltage of 0.5 V is output from the rectifier from the start of the mold drop into the electroforming liquid, and the state is maintained for 3 seconds after the mold reaches the lowest point. This is to protect the mold from being corroded. In this method, the output of the rectifier is stopped for 5 seconds in order to switch between constant voltage output and current output. Thereafter, the current output is started, and the current output is increased to 125 A over 30 seconds, and the accumulated time current is accumulated.
However, in this rectifier control, defective states such as protrusions and pinholes occur in the metal sheet formed on the mold surface, which causes a decrease in the yield rate.
[0005]
[Problems to be solved by the invention]
The present invention provides a method for producing a seamless flexible endless metal sheet that does not generate protrusions, pinholes, etc., and provides a substrate for an electrophotographic photoreceptor comprising the metal sheet, An object of the present invention is to provide an electrophotographic photosensitive member that can obtain an excellent image without image defects using the photosensitive member.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present inventors have intensively studied and as a result, the present invention has been completed. The following method for producing a seamless flexible endless metal sheet, an electrophotographic photoreceptor substrate, and an electrophotographic photoreceptor are provided.
(1) A method for producing a seamless flexible endless metal sheet body, wherein (i) a step of lowering and immersing a mold for forming the metal sheet body on the surface of the electroforming liquid; (Ii) a step of forming a metal film on the surface of the mold by applying a voltage between the electrodes using the immersed mold as a cathode and a metal as an anode, and (iii) forming the metal film from the mold surface And (iv) a step of applying a voltage between the mold and the metal immediately before immersing the mold in the electroforming liquid . ( V ) the mold. ( Vi ) after the entire mold has been immersed in the electroforming solution, the voltage is continuously applied from the step of supplying the minute current between the metal and the metal. And a step of raising until it is obtained. A method for producing a seamless flexible endless metal sheet. (2) The method according to (1), wherein nickel is used as the metal and a nickel film is formed on the mold surface using a nickel sulfamate aqueous solution as the electroforming solution. (3) A base for an electrophotographic photosensitive member comprising a seamless flexible endless metal sheet obtained by the method according to (1) or (2). (4) An electrophotographic photosensitive member, wherein a photosensitive layer is formed on the surface of the substrate according to (3).
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Next, the present invention will be described in detail with reference to the drawings. FIG. 1 shows an apparatus system diagram when the method of the present invention is carried out. In Figure 1, 1 is conductive picolinimidate, 2 electric Ieki, 3 a cathode (mold), the anode case 4, 5 the anode, 6 months Seo Dokesu, 7 slit portion of the cathode casing, 8 is a rectifier , 9 is an electroforming liquid circulation pump, 10 is a filter for removing foreign matters from the electroforming liquid, and 11 is an electroforming liquid circulation pipe. In the system diagram shown in FIG. 1, the mold is rotatably arranged and acts as a cathode, and a metal (metal film) deposited on the surface of the metal can be easily peeled off (metal ( For example, stainless steel may be used. The anode case 4 (titanium case or the like) accommodates an anode 5 (anode nickel or the like) therein. A cathode case 6 is disposed around the cathode 3, and a slit portion 7 is formed in the cathode case. The electroforming tank 1 is filled with an electroforming liquid (an aqueous solution of a metal salt such as Ni or Co) 2.
[0008]
When a voltage is applied between the mold 3 and the anode 5 in accordance with the apparatus system diagram shown in FIG. 1, metal ions are eluted from the anode 5, and the metal ions are deposited on the surface of the rotating mold 3. On the surface of 3, a seamless endless metal sheet is formed. The metal sheet body is peeled and collected from the mold to obtain a product. In the present invention, when a voltage is applied between the mold 3 and the anode 5 via the rectifier 8, if a voltage is applied immediately before the mold 3 is immersed in the electroforming liquid 2, the mold is A minute current flows between the mold 3 and the anode 5 from when the 3 contacts the electroforming liquid 2 (at the start of immersion) . The voltage in this case is a constant voltage of about 0.1 to 1 volt, preferably about 0.3 to 0.7 volt (constant voltage operation), and is continued until the entire mold 3 is immersed in the electroforming liquid 2. In the present invention, after the entire mold 3 is immersed in the electroforming liquid 2 , the voltage is immediately increased until a predetermined current is obtained, and rectifier control is performed so that a predetermined current value is obtained at this time (constant current). operation).
[0009]
【Example】
EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated, this invention is not limited at all by these Examples.
[Preparation of electroforming solution]
Nickel sulfamate solution (manufactured by Nippon Kagaku Sangyo Co., Ltd.) 350 to 600 g / L, nickel halide (nickel chloride or nickel bromide) 5 to 30 g / L, boric acid 20 to 40 g / L, Nickelite S (Japan) An appropriate amount of 2 to 1 g / L of sodium ethyl sulfate was prepared to prepare 400 L of an electroforming solution.
[Electroforming conditions]
A stainless steel mold was used on the cathode side, and nickel S pellets (manufactured by Shimura Chemical Co., Ltd.) were used on the anode side.
The energization time was set to 125 A × 30 min, the mold rotation speed was set to 6 rpm, and the electroforming liquid temperature was 50 ° C., and a seamless endless member having a diameter of 168 mm, a length of 466 mm, and a thickness of 30 μm was produced.
Based on the above conditions, rectifier control was changed to reduce protrusions and pinholes.
[0010]
[Production of seamless endless flexible member]
Comparative Example 1
FIG. 2 is a diagram illustrating output control of a conventional rectifier.
t1 indicates the time (3 seconds) from the lowest point when the molding die starts to descend to the plating tank, and a constant voltage of 0.5 V is output during this period from the beginning of the descent.
t2 indicates the time to stop the rectifier output from the end of the constant voltage output, and the output of the rectifier was stopped for 5 seconds.
t3 is a time for starting the output of current from the end of the output stop and increasing the current value to the target current value. The current value was increased to the set current value of 125 A in 30 seconds.
t4 indicates the time during which the current is accumulated at the set current value, and the current is accumulated at 125 A for 30 minutes.
Tables 1 and 2 show the results of producing seamless endless metal (nickel) sheet bodies by this control method.
[0011]
In the appearance inspection, the surface of the substrate was visually checked.
As check items, we checked all products that produced protrusions, pinholes, mask melons, fingerprint oil, kinks, scratches, scratches, circumferential scratches, crossing irregularities, spots, cloudiness, and removal.
[0012]
As shown in Table 1, in the conventional control method, 532 substrates were manufactured and the appearance of the substrate was inspected. As a result, the number of acceptable products was 457, the non-defective product rate was 85.9%, and the number of rejected products was 75, the defective rate. 14.1%.
As shown in Table 2, the breakdown of the defect items is 39 protrusions, defect occurrence rate of 7.3%, 13 pinholes, defect occurrence rate of 2.4%, and these two items are 69.3%. It can be seen that it accounts for the majority of items.
[0013]
[Table 1]
[0014]
[Table 2]
[0015]
Examples 1 and 2
FIG. 3 is a diagram for performing output of the rectifier according to the control method of the present invention.
A constant voltage of 0.5 V was output during t1 from the start of mold lowering as in the conventional case.
Conventionally, the output of the rectifier was stopped for 5 seconds in order to switch from the constant voltage output at t2 to the current output, but it was determined that no interval was required to switch between the voltage output and the current output, and the cause of corrosion of the mold The output stop time of the current becomes zero. Following the end of t1, the current value was increased from the output 0A to the set current value of 125A in 30 seconds from t3.
At t4, accumulation was performed at 125A for 30 minutes.
Tables 3 and 4 show the results of manufacturing a seamless endless metal sheet with this control method.
[0016]
As shown in Table 3, the control system of the present invention produced 552 bases and conducted a substrate appearance inspection. As a result, the number of acceptable products was 530, and the non-defective product rate was 96.0%, which was higher than the conventional system. There are 22 products and the defect rate is 4.0%.
The protrusions and pinholes of defective items, which accounted for most of the defective products with 69.3% in the conventional method, were greatly improved to 3 each, incidence 0.5%, 2 occurrence 0.4% You can see that
[0017]
[Table 3]
[0018]
[Table 4]
[Production of photoconductor]
A photoconductor was produced on the surface of a seamless flexible endless metal sheet by the above rectifier control method and the following procedure.
(Formation of undercoat layer)
15 parts by weight of alkyd resin [Beccosol 1307-60-EL (Dainippon Ink & Chemicals)], 10 parts by weight of melamine resin [Super Becamine G-821-60 (Dainippon Ink & Chemicals)], methyl ethyl ketone It melt | dissolved in 150 weight part, 90 weight part of titanium oxide powder [Taiperu CR-EL (made by Ishihara Sangyo Co., Ltd.)] was added to this, and it disperse | distributed for 12 hours with the ball mill, and prepared the coating liquid for undercoat layers.
Next, after washing the produced seamless endless metal sheet body, the undercoat layer coating solution was applied by dip coating, dried at 130 ° C. for 20 minutes, and the thickness was reduced to 3.5 μm. A draw layer was formed.
[0019]
(Formation of charge generation layer)
4 parts by weight of polyvinyl butyral resin [S-LEC HL-S (manufactured by Sekisui Chemical Co., Ltd.)] is dissolved in 150 parts by weight of cyclohexanone, and 10 parts by weight is added to the trisazo pigment represented by the following structural formula (1). After dispersion for 48 hours, 210 parts by weight of cyclohexanone was further added and dispersion was performed for 3 hours.
This was taken out into a container and diluted with cyclohexanone so that the solid content was 1.5% by weight.
The charge generation layer coating solution thus obtained was applied onto the undercoat layer by dip coating and dried at 130 ° C. for 20 minutes to form a charge generation layer having a thickness of 0.2 μm.
[0020]
[Chemical 1]
[0021]
(Formation of charge transport layer)
In 83 parts of tetrahydrofuran, 10 parts of bisphenol A type polycarbonate resin and 0.002 part of silicon oil [(KF-50 (manufactured by Shin-Etsu Chemical Co., Ltd.)]) are dissolved, and 8 wt. A charge transport layer coating solution was prepared by adding parts.
The charge transport layer coating solution thus obtained was dip-coated on the charge generation layer and then dried at 110 ° C. for 20 minutes to form a charge transport layer having a thickness of 20 μm.
[0022]
[Chemical 2]
[0023]
The photoreceptor was mounted on a unit and image evaluation was performed.
For image evaluation, a full-color laser printer IPSIO Color 6000 (manufactured by Ricoh (λ = 780 nm, 600 dpi, beam diameter 76 × 76 μm)) was used to output a halftone image, and the presence or absence of image defects was examined.
Evaluation evaluated all the images which passed the electrophotographic photoreceptor appearance inspection. .
Table 5 shows the image evaluation results.
A circle in Table 5 indicates that there is no problem in the halftone image.
[0024]
[Table 5]
[0025]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, while providing the method for producing the electrophotographic photoreceptor base | substrate which consists of a seamless flexible endless metal sheet body which does not generate | occur | produce a protrusion, a pinhole, etc., while being excellent in there being no image defect An electrophotographic photoreceptor substrate, an electrophotographic photoreceptor, and an electrophotographic apparatus that can obtain an image are provided, and the contribution to the electrophotographic field is extremely large.
[Brief description of the drawings]
FIG. 1 is an overall view showing a method for producing a molding die of the present invention.
FIG. 2 is a diagram illustrating output control of a conventional rectifier.
FIG. 3 is a diagram illustrating output of a rectifier according to the control method of the present invention.
[Explanation of symbols]
1 Electroforming tank 2 Electroforming liquid 3 Cathode (die)
DESCRIPTION OF SYMBOLS 4 Anode case 5 Anode 6 Cathode case 7 Slit part 8 Rectifier 9 Electroforming liquid circulation pump 10 Foreign matter filter 11 of electroforming liquid Electroforming liquid circulation piping

Claims (4)

A method for producing a seamless flexible endless metal sheet body, wherein (i) a step of lowering and immersing a mold for forming the metal sheet body on the surface of the electroforming liquid; (ii) A step of forming a metal film on the surface of the mold by applying a voltage between the electrodes using the immersed mold as a cathode and a metal as an anode, and (iii) separating and collecting the metal film from the surface of the mold (Iv) a step of applying a voltage between the mold and the metal immediately before immersing the mold in the electroforming solution , ( v ) the mold and the metal. step of flowing a minute current from the time start of immersion between, after immersion in (vi) the mold entirely conductive Ieki, to a predetermined current value continuously from the step of flowing a minute current to the voltage is obtained A method of producing a seamless flexible endless metal sheet comprising the step of raising.   The method according to claim 1, wherein nickel is used as the metal and a nickel film is formed on the mold surface using an aqueous nickel sulfamate solution as the electroforming solution.   An electrophotographic photoreceptor substrate comprising a seamless flexible endless metal sheet obtained by the method according to claim 1.   An electrophotographic photosensitive member, wherein a photosensitive layer is formed on the surface of the substrate according to claim 3.