Electrophotographic photoconductor, production method of the same, image forming apparatus, and process cartridge

A method for producing an electrophotographic photoconductor having a photosensitive layer and a crosslinked resin surface layer over a support wherein the crosslinked resin surface layer is a layer which is cured by UV irradiation after (i) the photosensitive layer is sprayed with a crosslinked-resin-surface-layer coating liquid to form a wet film and (ii) the wet film is sprayed with water,

• wherein shapes of concaves and convexes in a surface of the electrophotographic photoconductor are measured by a surface roughness/profile measuring device to obtain one-dimensional data arrays, the one-dimensional data arrays are subjected to a multiresolution analysis (MRA-1) through wavelet transformation so as to be separated into six frequency components including a highest frequency component (HHH), a second highest frequency component (HHL), a third highest frequency component (HMH), a fourth highest frequency component (HML), a fifth highest frequency component (HLH) and a lowest frequency component (HLL), the one-dimensional data arrays of the lowest frequency component (HLL) thus obtained are thinned out so that the number of data arrays is reduced to 1/10 to 1/100 thereof to thereby produce one-dimensional data arrays, the one-dimensional data arrays thus produced are subjected to a multiresolution analysis (MRA-2) through wavelet transformation so as to be separated into six frequency components including a highest frequency component (LHH), a second highest frequency component (LHL), third highest frequency component (LMH), a fourth highest frequency component (LML), a fifth highest frequency component (LLH) and a lowest frequency component (LLL) to thereby obtain 12 frequency components in total;
• and
• the method includes processing the crosslinked resin surface layer to obtain a center-line average roughness (WRa) of each of 7 frequency components out of the 12 frequency components satisfying a relationship (i) below,
• 1−597×WRa(HML)+238×WRa(HLH)−95×WRa(LHL)+84×WRa(LMH)−79×WRa(LML)+55×WRa(LLH)−17×WRa(LLL)>0 (i)
• where a center-line average roughness (WRa) of each of the frequency components is a center-line average roughness based on one-dimensional data arrays, which is obtained by a procedure in which shapes of concaves and convexes in a surface of the electrophotographic photoconductor are measured by a surface roughness/profile measuring device to obtain one-dimensional data arrays, and the one-dimensional data arrays are subjected to the multiresolution analyses (MRA-1) and (MRA-2) so as to be separated into different frequency components ranging from a highest frequency component to a lowest frequency component;
• and HML, HLH, LHL, LMH, LML, LLH, and LLL each represent an individual frequency band obtained when the one-dimensional data arrays are separated into frequency components having one concave-convex cycle length of from 4 μm to 25 μm, from 10 μm to 50 μm, from 53 μm to 183 μm, from 106 μm to 318 μm, from 214 μm to 551 μm, from 431 μm to 954 μm, and from 867 μm to 1,654 μm, in this order.

An image forming apparatus comprising:

• an electrophotographic photoconductor,
• a solid-lubricant applying unit which scrapes a solid lubricant with a brush roller and applies the scraped solid lubricant onto the electrophotographic photoconductor, and
• a coating blade for spreading the solid lubricant over a surface of the electrophotographic photoconductor,
• wherein the electrophotographic photoconductor comprises:
• a support,
• a photosensitive layer, and
• a crosslinked resin surface layer, the photosensitive layer and crosslinked resin surface layer being provided over the support wherein the crosslinked resin surface layer is a layer which is cured by UV irradiation after (i) the photosensitive layer is sprayed with a crosslinked-resin-surface-layer coating liquid to form a wet film and (ii) the wet film is sprayed with water,
• wherein shapes of concaves and convexes in a surface of the electrophotographic photoconductor are measured by a surface roughness/profile measuring device to obtain one-dimensional data arrays, the one-dimensional data arrays are subjected to a multiresolution analysis (MRA-1) through wavelet transformation so as to be separated into six frequency components including a highest frequency component (HHH), a second highest frequency component (HHL), a third highest frequency component (HMH), a fourth highest frequency component (HML), a fifth highest frequency component (HLH) and a lowest frequency component (HLL), the one-dimensional data arrays of the lowest frequency component (HLL) thus obtained are thinned out so that the number of data arrays is reduced to 1/10 to 1/100 thereof to thereby produce one-dimensional data arrays, the one-dimensional data arrays thus produced are subjected to a multiresolution analysis (MRA-2) through wavelet transformation so as to be separated into six frequency components including a highest frequency component (LHH), a second highest frequency component (LHL), third highest frequency component (LMH), a fourth highest frequency component (LML), a fifth highest frequency component (LLH) and a lowest frequency component (LLL) to thereby obtain 12 frequency components in total;
• and the crosslinked resin surface layer is processed to obtain a center-line average roughness (WRa) of each of 7 frequency components out of the 12 frequency components satisfying a relationship (i) below,
• 1−597×WRa(HML)+238×WRa(HLH)−95×WRa(LHL)+84×WRa(LMH)−79×WRa(LML)+55×WRa(LLH)−17×WRa(LLL)>0 (i)
• where a center-line average roughness (WRa) of each of the frequency components is a center-line average roughness based on one-dimensional data arrays, which is obtained by a procedure in which shapes of concaves and convexes in a surface of the electrophotographic photoconductor are measured by a surface roughness/profile measuring device to obtain one-dimensional data arrays, and the one-dimensional data arrays are subjected to multiresolution analyses (MRA-1) and (MRA-2) so as to be separated into different frequency components ranging from a highest frequency component to a lowest frequency component;
• and HML, HLH, LHL, LMH, LML, LLH, and LLL each represent an individual frequency band obtained when the one-dimensional data arrays are separated into frequency components having one concave-convex cycle length of from 4 μm to 25 μm, from 10 μm to 50 μm, from 53 μm to 183 μm, from 106 μm to 318 μm, from 214 μm to 551 μm, from 431 μm to 954 μm, and from 867 μm to 1,654 μm, in this order.