JP5211756B2 - Method for evaluating surface shape of parts for electrophotographic apparatus such as electrophotographic photosensitive member - Google Patents

Description

  The present invention relates to a surface shape evaluation method for parts for an electrophotographic apparatus such as an electrophotographic photosensitive member.

In an electrophotographic image forming apparatus, the toner particle size is being reduced for the purpose of improving image quality.
As a method for reducing the particle size of toner, in addition to the conventional method of reducing the particle size by a pulverization method, a method for producing a small particle size toner by a polymerization method has been developed in recent years. Toner that has been put on the market.
In producing a small-diameter toner, the polymerization method requires less energy for production than the pulverization method, and polymerization toner has been made for the purpose of reducing the energy necessary for production.

By using a toner having a small particle diameter, high image quality can be realized by improving resolution and improving fine gradation expression. However, the following problems peculiar to the small particle size toner occur in the image forming process using the small particle size toner.
The problem in cleaning is one of them, and there is a problem that the adhesion force of the toner to the photosensitive member is apparently increased due to the reduction in the particle size of the toner, which makes cleaning difficult.
In particular, since the toner produced by the polymerization method has a small particle size and particles close to a spherical shape, the toner is separated from the photoconductor and the cleaning blade in the cleaning process of cleaning the photoconductor with a cleaning blade. There is a strong tendency for so-called “slip-out” to pass between the edges of the edges, resulting in poor cleaning.

As a method for improving the cleaning performance in an electrophotographic apparatus using such a small particle size toner or polymerized toner, a method of roughening the surface of the photoreceptor has been studied.
For example, as a method related to the roughening of the surface of the electrophotographic photosensitive member, Patent Document 1 discloses that the surface roughness of the electrophotographic photosensitive member is easy to separate the transfer material from the surface of the electrophotographic photosensitive member. Is disclosed in the art.

Patent Document 2 discloses a method for roughening the surface of an electrophotographic photosensitive member into a crushed skin shape by controlling the drying conditions when forming the surface layer.
Patent Document 3 discloses a technique for roughening the surface of an electrophotographic photosensitive member by containing particles in a surface layer.
Patent Document 4 discloses a technique for roughening the surface of an electrophotographic photosensitive member by polishing the surface of the surface layer using a metal wire brush.
Japanese Patent Laid-Open No. 2004-260688 discloses a method for solving cleaning blade reversal and edge chipping, which are problems when used in an electrophotographic apparatus having a specific process speed or higher, using specific cleaning means and toner. A technique for roughening the surface of an electrophotographic photosensitive member is disclosed.

Patent Document 6 discloses a technique for roughening the surface of an electrophotographic photosensitive member by polishing the surface of a surface layer using a film-like abrasive.
Patent Document 7 discloses a technique of roughening the peripheral surface of the electrophotographic photosensitive member by blasting in order to prevent the cleaning blade from being reversed (edge) and the edge portion from being broken (notched).
Patent Document 8 discloses an electrophotographic photosensitive member having a plurality of dimple-shaped concave portions on the surface.
Patent Documents 9 and 10 also show electrophotographic photosensitive members having a plurality of dimple-shaped concave portions on the surface.

As described above, as a method for improving the cleaning performance of the electrophotographic photosensitive member, a method of roughening the surface of the electrophotographic photosensitive member is effective.
Here, the surface roughness of the electrophotographic photosensitive member is an important characteristic item, but in the past, it was often measured and determined by the surface roughness defined in JIS B0601 and the like.

Widely used measurement methods include arithmetic average roughness (Ra), maximum height (Rmax), ten-point average roughness (Rz), and the like. However, in these evaluation methods, there is a problem that the value is shaken when there are concave portions or convex portions that are separated from each other within the measurement range.
However, conventionally, there is no good method for evaluating the degree of roughening, and a parameter indicating the degree of roughening has been studied. This is shown below.

  In patent document 11, on the cross-sectional curve 1 obtained by measuring the surface shape with a surface roughness measuring device, a partition width X centered on the average line 2 is defined, and adjacent mountains and valleys exceeding this partition width are defined. The surface shape is evaluated based on the number per unit length L of the peak 4 consisting of a pair. By using such a method, an organic photoreceptor is produced using a substrate in which the number of peaks 4 is 100 or less when the partition width X is 20 μm and the unit length L is 1 cm.

  In Patent Document 12, in order to solve the problem that poor cleaning is likely to occur when a small particle size toner is used for the purpose of improving image quality, charged toner is exposed to light so that a high quality image can be formed. A cleaning roller to which a bias voltage that separates from the body is applied is provided on the upstream side of the cleaning blade, and a photoreceptor having a surface roughness Rz of 0.1 μm to 2.5 μm on an average of 10 points is used.

Patent Document 13 shows a method of satisfying ΔT> Rz and 0 nm <ΔT + Rz <5 nm, where ΔT and Rz are the thickness loss and surface roughness per kilocycle (kcycle) of the electrophotographic photosensitive member, respectively. ing.
In Patent Document 14, the surface of the photosensitive layer is roughened, and the glossiness of the surface of the photoreceptor after the roughening treatment is measured. The standard deviation of the measured value is 4 or less. Is shown.

In Patent Document 15, a system including a blade, a toner composition, and an unused image forming member as claim 1, the surface on which the image forming member applies the toner composition to form a latent image. And the surface is R / a _nn ⁴ > K _B (1-σ ² ) / 32πEt ² a _f
And ^{_{R / a nn 2 <√3 /}} 8π 2 · (1 + μ 2) / μ · K B / Γ · t / a f · θ
(In the above formulas, R is the average height of the convex portion of the surface, a _nn is the half of the nearest neighbor distance between the convex portions on the surface, the bulk modulus of the K _B blade Σ is the Poisson's ratio of the toner composition, E is the Young's modulus of the toner composition, t is the average thickness of the flat particles in the toner composition, and a _f is the flat particle Is the average radius, μ is the average of the toner blade friction coefficient and the toner surface friction coefficient, Γ is the Dupre 'work of adhesion between the surface and flat particles, and θ is the blade tip angle is there.)
2 shows a system having a surface roughness defined by

In Patent Document 9 shown above, as Claim 1, in a cylindrical electrophotographic photosensitive member having a cylindrical support and an organic photosensitive layer provided on the cylindrical support, the periphery of the electrophotographic photosensitive member is defined. The surface has a plurality of dimple-shaped recesses, the ten-point average roughness Rzjis (A) measured by sweeping in the circumferential direction of the peripheral surface of the electrophotographic photosensitive member is 0.3 to 2.5 μm, and the electron The ten-point average roughness Rzjis (B) measured by sweeping in the generatrix direction of the peripheral surface of the photographic photoreceptor is 0.3 to 2.5 μm, and swept in the peripheral direction of the peripheral surface of the electrophotographic photoreceptor. The measured unevenness average interval RSm (C) is 5 to 120 μm, the average unevenness interval RSm (D) measured by sweeping in the generatrix direction of the peripheral surface of the electrophotographic photosensitive member is 5 to 120 μm, The average interval RSm (D) of the unevenness relative to the average interval RSm (C) of the unevenness (D / C) is 0.5 to 1.5, the longest diameter is in the range of 1 to 50 μm and the depth is in the range of 0.1 to 2.5 μm among the dimple-shaped recesses The electrophotographic photosensitive member is characterized in that the number of dimple-shaped concave portions is 5 to 50 per 10,000 μm ^{2 on} the peripheral surface of the electrophotographic photosensitive member.

Further, as the second aspect, the ten-point average roughness Rzjis (A) is 0.4 to 2.0 μm, the ten-point average roughness Rzjis (B) is 0.4 to 2.0 μm, The average interval RSm (C) of the unevenness is 10 to 100 μm, the average interval RSm (D) of the unevenness is 10 to 100 μm, and the average interval RSm (C) of the unevenness of the average interval RSm (D) of the unevenness The electrophotographic photosensitive member according to claim 1, wherein the ratio (D / C) to the ratio is 0.8 to 1.2.
According to a third aspect of the present invention, the maximum peak height Rp (F) of the peripheral surface of the electrophotographic photosensitive member is 0.6 μm or less, and the maximum valley depth Rv (E) of the peripheral surface of the electrophotographic photosensitive member is The electrophotographic photosensitive member according to claim 1 or 2, wherein a ratio value (E / F) to the maximum peak height Rp (F) is 1.2 or more.

Similarly, in Patent Document 10 shown above, in an electrophotographic photosensitive member having a support and an organic photosensitive layer provided on the support, a dimple-shaped recess is formed on the surface of the surface layer of the electrophotographic photosensitive member. The number of dimple-shaped recesses that are formed in a plurality and have a longest diameter in the range of 1 to 50 μm, a depth of 0.1 μm or more, and a volume of 1 μm ³ or more. Dimples formed on the surface of the surface layer at the interface between the surface layer and the layer immediately below the surface layer. 1 shows an electrophotographic photosensitive member in which a plurality of concave portions corresponding to a concave portion of a shape are formed.

  In Patent Document 16, a photosensitive layer is provided on a conductive support, and a plurality of image carriers on which the surface is exposed and an electrostatic latent image is formed are provided corresponding to each of the plurality of image carriers. A plurality of developing devices for developing the electrostatic latent image with a developer; and a cleaning unit for rubbing the surface of the image carrier provided corresponding to the plurality of image carriers to remove the developer. An image forming apparatus in which at least a pair of developing devices among the plurality of developing devices store developers having the same hue and different brightness, and the developer stored in the developing device corresponding to each image carrier. The image forming apparatus is characterized in that the 10-point average roughness Rz of the surface in the initial state is adjusted according to the lightness.

In Patent Document 17, the 10-point average roughness Rz is 0.1 μm or more and 1.5 μm or less, or the maximum height Rz is 2.5 μm or less, and the JIS-A hardness is 70 degrees or more and 80 degrees or less. Measured when a polyurethane flat belt having a width of 5 mm, a length of 325 mm, a thickness of 2 mm, and a weight of 4.58 g is loaded with a load of 100 g, the contact length in the circumferential direction is 3 mm, and the contact area is 15 mm ^2. 1 shows an image forming apparatus characterized in that an image is formed by using an electrophotographic photosensitive member having a surface property such that a frictional resistance Rf as a tensile load is 45 gf <Rf <200 gf.

In Patent Document 18, a latent image formed on an electrophotographic photosensitive member is developed with a developer, and a toner image visualized by the development is transferred to an intermediate transfer member. A secondary transfer step of transferring the transferred toner image to a recording material, and transferring the toner image to the recording material and then removing residual toner on the electrophotographic photosensitive member in a cleaning step. The surface roughness Ra of the photosensitive member is 0.02 to 0.1 μm, the surface roughness Rz of the intermediate transfer member is 0.4 μm to 2.0 μm, and the surface energy of the electrophotographic photosensitive member is reduced. An image forming method is characterized in that an agent is supplied and image formation is performed.
Patent Document 19 discloses an image forming apparatus in which the organic photoreceptor has an average value of the period of surface irregularities that is 10 times or more the volume average particle diameter of toner.

In Patent Document 20, in an electrophotographic apparatus including an electrophotographic photosensitive member rotating at a peripheral speed of 200 mm / sec or more and a cleaning unit, the electrophotographic photosensitive member has a photosensitive layer and a surface protective layer on a conductive support, The surface protective layer contains 35.0 to 45.0% by mass of fluorine atom-containing resin particles with respect to the total mass of the protective layer, and the surface roughness is 0.1 to 5.0 μm in terms of 10-point average surface roughness. An electrophotographic photosensitive member having a surface hardness of 0.1 to 10.0 according to the Taber abrasion test method and a surface friction coefficient of 0.1 to 0.7, and the cleaning means is a rubber elastic blade. The linear pressure of the blade against the electrophotographic photosensitive member is 0.294 N to 0.441 N / cm, and the glass transition point (Tg) of the toner used is 40 ° C. to 55 ° C. A certain tensile modulus (Y 'S modulus) is 784N~980N / cm ^2, and impact resilience value is 35% to 55%, shows the electrophotographic apparatus is characterized by containing a fluorine atom resin fine particles to the substrate surface Yes.

In Patent Document 21, the flatness (d / t) (d: volume average particle diameter, t: toner particle thickness) of the toner and the surface roughness of the image forming body are expressed as a center line average roughness Ra (μm). As shown, an image forming method using an image forming body having a relationship of d / t × 0.01 ≦ Ra ≦ 0.5 is shown.
Patent Documents 22 to 24 show an image forming apparatus in which irregularities smaller than the volume average particle diameter of the spherical toner are provided on the surface of the image carrier.

  In Patent Document 25, in an electrophotographic apparatus including an electrophotographic photosensitive member rotating at a peripheral speed of 200 mm / sec or more and a cleaning unit, the electrophotographic photosensitive member has a photosensitive layer and a surface protective layer on a conductive support, The surface protective layer contains 15.0 to 40.0% by mass of fluorine atom-containing resin particles with respect to the total mass of the protective layer, and the surface roughness is 0.1 to 5.0 μm in terms of 10-point average surface roughness. The electrophotographic photosensitive member has a surface hardness of 0.1 to 20.0 in the Taber abrasion test method and a surface friction coefficient of 0.001 to 1.2.

As a method for evaluating the surface shape, the present inventor has shown a surface shape evaluation method using Fourier transform in Patent Documents 26 to 35.
In addition, in the Patent Document 36, the present inventor obtains a cross-sectional curve defined in JIS B0601 from an arbitrary position on the surface of the substrate with a length of 100 μm in the axial direction, and the vertical axis of the cross-sectional curve at equally spaced positions in the horizontal axis direction. Measure the position in the direction, determine the dispersion defined in JIS Z8101 at that position, determine the measurement values selected from the surface roughness Ra, Rz, Ry defined in JIS B0601, and use these dispersion and measurement values to determine the substrate A method for evaluating surface roughness is shown.

  Further, in Patent Document 37, a cross-sectional curve defined in JIS B0601 is obtained for the surface state of a part for an image forming apparatus, and a multi-resolution analysis of a position data string in a surface roughness direction at equal intervals on the cross-sectional curve is performed. It shows a method for evaluating the surface roughness state based on at least the result.

Further, in Patent Document 38, a cross-sectional curve defined in JISB0601 is obtained for the surface state of the image forming apparatus component, and a multi-resolution analysis of a position data string in the surface roughness direction at equal intervals on the cross-sectional curve is performed. 2 shows an electrophotographic photosensitive member substrate characterized in that it is evaluated by a method for evaluating the surface roughness of parts for an image forming apparatus that evaluates the state of surface roughness based on the result.
However, any of the above surface roughness measurement methods has a problem that the cleaning performance in an electrophotographic apparatus using a small particle size toner or a polymerized toner cannot be evaluated.
That is, there is a problem that the surface roughness cannot be accurately grasped by the methods such as surface roughness Ra, Rmax, Rz and the like conventionally used as the surface roughness expression method.
Because of these problems, conventionally, when measuring the surface roughness, the recording chart of the surface roughness meter was saved and judged from the cutting waveform recorded on the recording chart. There was a problem that had to be read and required skill.

As described above, the conventional surface roughness (centerline surface roughness Ra, Rmax, Rz) evaluation method cannot completely evaluate the cleaning performance in an electrophotographic apparatus using a toner having a small particle diameter or polymerized toner. was there.
In addition, as described above, in the Fourier transform, a change that appears frequently in a signal can be grasped as the frequency distribution, but there is a problem that is not effective for examining a change with a low frequency. Further, the result of Fourier transform has a problem that it is not known where the change has occurred.
In response to these problems, the inventor has devised the electrophotographic photoreceptor substrate of Patent Document 38 described above, but a better method has been desired.

JP-A-53-092133 JP-A-53-092133 JP-A-52-026226 JP-A-57-094772 Japanese Patent Laid-Open No. 01-099060 Japanese Patent Laid-Open No. 02-139666 Japanese Patent Laid-Open No. 02-150850 JP 2007-86523 A Japanese Patent No. 3938209 Japanese Patent No. 3938210 Japanese Unexamined Patent Publication No. 07-104497 JP 2002-196645 A JP 2006-163302 A Japanese Patent Laid-Open No. 2007-86319 Japanese Patent No. 3040540 JP 2005-345788 A JP 2004-258588 A JP 2004-54001 A JP 2003-270840 A JP 2003-241408 A JP 2003-131537 A JP 2002-296994 A JP 2002-258705 A JP 2002-299406 A JP 2002-82468 A JP 2001-265014 A JP 2001-289630 A JP 2002-251029 A JP 2002-296822 A JP 2002-296823 A JP 2002-296824 A JP 2002-341572 A JP 2006-53576 A JP 2006-53577 A JP 2006-79102 A Japanese Patent Laid-Open No. 2004-117454 JP 2004-61359 A JP 2007-292772 A

  An object of this invention is to provide the evaluation method which measures the surface state of a measurement object in detail in the measurement of surface shape.

According to the present invention, the above problem is solved by the following technical means.
(1) Multiplexing that separates a one-dimensional data array obtained by measuring an uneven shape on the surface of a part for an electrophotographic apparatus with a surface roughness meter into a plurality of frequency components from a high frequency component to a low frequency component by wavelet transform A resolution analysis is performed, and a one-dimensional data array is created by thinning out the lowest frequency component obtained here so that the number of data arrays is reduced to 1/10 to 1/100. A wavelet transform is performed to perform a multi-resolution analysis that separates a plurality of frequency components from a high frequency component to a low frequency component, and the center line average roughness Ra, the maximum height Rmax, 10 A method for evaluating the surface shape of a part for an electrophotographic apparatus, wherein the point average roughness Rz is obtained.
(Here, the centerline average roughness Ra means that the roughness curve obtained by measuring with a surface roughness meter is folded from the centerline, and the area obtained by the roughness curve and the centerline is the reference length L. The value divided by is expressed in micrometers (μm), where the reference length L is the measurement length.
The maximum height Rmax is a roughness curve obtained by measuring with a surface roughness meter, and is expressed in micrometers (μm) by obtaining the maximum height of a portion from which the reference length L is extracted.
The ten-point average roughness Rz is the average value of the elevation of the peak from the highest to the fifth and the average value of the elevation of the valley from the deepest to the fifth in the part where only the reference length L is extracted from the cross-sectional curve. The difference value is expressed in micrometers (μm). )
(2) The surface shape evaluation method according to (1), wherein the component for an electrophotographic apparatus is an electrophotographic photosensitive member.
(3) The surface shape evaluation method according to (1), wherein the component for an electrophotographic apparatus is a kind selected from a transfer roller, a transfer belt, a fixing roller, a fixing belt, a conveyance roller, and a conveyance belt.
(4) The surface according to any one of (1) to (3), wherein the first multiresolution analysis and the second multiresolution analysis perform multiresolution analysis on four or more frequency components. Shape evaluation method.

  In the present invention, the electrophotographic device component means various rollers or various belts used in an electrophotographic device such as a transfer roller, a transfer belt, a fixing roller, a fixing belt, a conveying roller, and a conveying belt. It is known that the surface shape of the electrophotographic apparatus parts greatly affects the print quality of the electrophotographic apparatus, and the method shown in the present invention can be used effectively.

The first effect of the present invention will be described.
According to the present invention, the first multi-resolution analysis by the wavelet transform is performed, and thinning is performed so that the number of data arrays is reduced from 1/10 to 1/100 with respect to the lowest frequency component obtained as a result. .
This will be explained with an example. For example, assume that the first multi-resolution analysis by wavelet transform is performed, and the number of data arrays of the lowest frequency component obtained as a result is 20000.
When 1/20 is thinned out from the 2000 data array, the data is picked up from the 2000 data array of the lowest frequency component every 1st, 21st, 41st, 61st and 20th, and new Is to make an array.
When 1/50 is thinned out from the 2000 data array, the data is picked up from the data array of the lowest frequency component 2000 at the first, 51st, 101st, 151st and every 50th. To create a new array.

In the above case, it is only necessary to thin out the data, that is, to extract the data every certain number of integers. However, when the number of data to be extracted is small, it is only necessary to calculate by calculating the proportion of the section. For example, when data is extracted every 50.1 from 10,000 data arrays, the calculation is performed as follows.
If the 50th data was data of _D 50, 51 th and _{D 51,} 50.1 -th data is calculated as follows.
D ₅₀ + (D ₅₁ −D ₅₀ ) × 0.1

In the present invention, the data array to be thinned out is the lowest frequency component that has already been subjected to wavelet transform and subjected to multi-resolution analysis. Since this data array does not include high frequency components, the high frequency component that is lost even if thinning is performed. There are no components and the information contained in the signal is not lost.
When thinning is performed on the original data before the wavelet transform, there is a problem that the value fluctuates depending on the position where the data is extracted from the original data by thinning.
As a measure to avoid this problem when thinning data without performing wavelet transform, a method of smoothing the original data by moving average method etc. can be considered, but in this method, how many values are moved Data may vary depending on whether it is averaged, and good data cannot be obtained.
However, according to the present invention, thinning is performed so that the number of data arrays is reduced from 1/10 to 1/100 with respect to the lowest frequency component obtained by performing the first wavelet transform. Even if it is done, little information is lost and accurate data analysis becomes possible.

Next, the second effect of the present invention will be described.
In the present invention, the first wavelet transform is performed, a multi-resolution analysis is performed to separate a plurality of frequency components from a high frequency component to a low frequency component, and the one-dimensional data obtained by thinning out the lowest frequency component obtained here is further obtained. A data array is created, and a wavelet transform is further performed on the one-dimensional data array to perform multi-resolution analysis that separates a plurality of frequency components from a high frequency component to a low frequency component.
In summary, the lowest frequency component obtained by the first multi-resolution analysis result is thinned to increase the apparent frequency of the signal, and the second multi-resolution analysis is further performed on the data. Yes.
By doing so, it becomes possible to perform more detailed frequency analysis on the lowest frequency component obtained by the first multi-resolution analysis result.

Next, the third effect of the present invention will be described.
In the present invention, the first wavelet transform is performed, a multi-resolution analysis is performed to separate a plurality of frequency components from a high frequency component to a low frequency component, and the one-dimensional data obtained by thinning out the lowest frequency component obtained here is further obtained. A data array is created, and a wavelet transform is further performed on the one-dimensional data array to perform multi-resolution analysis that separates a plurality of frequency components from a high frequency component to a low frequency component.
When multi-resolution analysis is performed and the original signal is separated into a plurality of bands according to the frequency band, depending on the frequency of the signal, the original signal may not be separated into one band and may be divided into a plurality of bands.
However, here, when the frequency to be noticed is known, the first wavelet transform is performed to perform a multi-resolution analysis that separates into a plurality of frequency components from a high frequency component to a low frequency component. When the minimum frequency component is thinned out, by adjusting the thinning ratio, even if the frequency of interest is subjected to the second multi-resolution analysis, it can be observed without being separated into two bands. .

Next, the fourth effect of the present invention will be described.
In the present invention, a one-dimensional data array obtained by measuring the uneven shape of the electrophotographic photosensitive member surface with a surface roughness meter is multiplexed into a plurality of frequency components from a high frequency component to a low frequency component by wavelet transform. Perform resolution analysis,
Furthermore, a one-dimensional data array in which the lowest frequency component obtained here is thinned out is created, and wavelet transform is further performed on this one-dimensional data array, so that a plurality of frequency components from high frequency components to low frequency components are separated. A multi-resolution analysis is performed, and a center line average roughness Ra, a maximum height Rmax, and a ten-point average roughness Rz are obtained for each obtained frequency component.
Thus, since the center line average roughness Ra, the maximum height Rmax, and the ten-point average roughness Rz are obtained from the multiresolution analysis result, the state of each frequency component can be easily quantified.

Here, the centerline average roughness Ra means that a roughness curve obtained by measuring with a surface roughness meter is folded from the centerline, and the area obtained by the roughness curve and the centerline is expressed by a reference length L. The divided value is expressed in micrometers (μm). Here, the reference length L is a measurement length.
The maximum height Rmax is a roughness curve obtained by measuring with a surface roughness meter, and is expressed in micrometers (μm) by obtaining the maximum height of a portion from which the reference length L is extracted.
The ten-point average roughness Rz is the average value of the highest elevation of the peak from the highest to the fifth and the average elevation of the bottom of the valley from the deepest to the fifth in the portion where only the reference length L is extracted from the roughness curve. The value of the difference is expressed in micrometers (μm).

  For each frequency component obtained by the multi-resolution analysis, the center line average roughness Ra, the maximum height Rmax, and the ten-point average roughness Rz are obtained. This is the same as the frequency component obtained by the second multi-resolution analysis. In addition to this, it may be performed on each frequency component obtained in the first multiresolution analysis. Here, the roughness curve may be referred to as a cross-sectional curve.

The present invention will be described in detail below.
In the surface roughness evaluation technique according to the first invention of the present application, first, a cross-sectional curve defined in JIS B0601 is obtained for the surface state of the part for an electrophotographic apparatus, and a one-dimensional data array which is the cross-sectional curve is obtained.
The one-dimensional data array that is the cross-sectional curve may be obtained as a digital signal from the surface roughness meter, or may be obtained by A / D converting the analog output of the surface roughness meter.
In the present invention, the measurement length is preferably the measurement length defined in the JIS standard, preferably 8 mm or more and 25 mm or less.
The sampling interval is preferably 1 μm or less, and preferably 0.2 μm or more and 0.5 μm or less.
For example, when measuring a measurement length of 12 mm with 30720 sampling points, the sampling interval is 0.390625 μm, which is suitable for implementing the present invention.

  This one-dimensional data array is subjected to multi-resolution analysis to separate it into multiple frequency components from high frequency components to low frequency components by wavelet transform, and the one-dimensional data array obtained by thinning out the lowest frequency components obtained here And then perform further wavelet transform on this one-dimensional data array to perform multi-resolution analysis that separates into multiple frequency components from high frequency components to low frequency components. Find the average roughness and maximum height.

In the present invention, the wavelet transformation is performed twice. The first wavelet transformation is referred to as the first wavelet transformation, and the subsequent wavelet transformation is referred to as the second wavelet transformation.
Here, various wavelet functions can be used as the mother wavelet function used for the first and second wavelet transforms, for example, a Daubecies function, a Harr function, and a Mayer function. A function, a Simlet function, a Coiflet function, and the like can be used. Here, “Daubecies” may be expressed as “Dovesy”.
In addition, when performing multi-resolution analysis in which wavelet transform is performed to separate a plurality of frequency components from high frequency components to low frequency components, the number of components is preferably 4 or more and 8 or less, and preferably 6.

  In the present invention, the first wavelet transform is performed to separate into a plurality of frequency components, and the lowest frequency component obtained here is thinned out to create a one-dimensional data array. The second wavelet transform is performed, and multi-resolution analysis is performed to separate a plurality of frequency components from high frequency components to low frequency components.

Here, the thinning performed on the lowest frequency component obtained as a result of the first wavelet transform is characterized in that the number of data arrays is reduced from 1/10 to 1/100.
Here, the data decimation has an effect of increasing the frequency of the data. For example, when the number of one-dimensional arrays obtained as a result of the first wavelet transform is 30000, if 1/10 decimation is performed, The number of arrays becomes 3000.
In this case, if the decimation is smaller than 1/10, for example, if it is 1/5, there is little effect of increasing the frequency of the data, and even if the second wavelet transform is performed and the multiresolution analysis is performed, the data is well separated. Not.
If the decimation is greater than 1/100, for example 1/200, the frequency of the data becomes too high, and even if the second wavelet transform is performed and the multi-resolution analysis is performed, the data is concentrated on high frequency components. And not well separated.

  FIG. 1 is a block diagram schematically showing a configuration example of a surface roughness evaluation apparatus for parts for an electrophotographic apparatus to which the first invention of the present application is applied. In the figure, reference numeral 1 denotes a measurement object such as a substrate for an electrophotographic photosensitive member or an object having an undercoat layer formed on the surface thereof, 2 is a jig to which a probe for measuring surface roughness is attached, and 3 is the jig 2 described above. 4 is a surface roughness meter, and 5 is a personal computer that performs signal analysis. In this figure, the above-described multi-resolution analysis calculation is performed by the personal computer 5.

  This figure is shown as an example, and the configuration may be other configurations. For example, the multi-resolution analysis may be performed not by a personal computer but by a dedicated numerical calculation processor. Moreover, you may perform this process with the surface roughness meter itself. Various methods can be used to display the results, and the results may be displayed on a CRT or a liquid crystal screen, or may be printed out. Further, it may be transmitted as an electrical signal to another device, or may be stored in a USB memory or an MO disk.

  In the measurement by the present inventor, the surface roughness meter uses a surfcom 570A manufactured by Tokyo Seimitsu Co., Ltd., the personal computer uses a personal computer manufactured by IBM, and the RS-232-C cable between the surfcom 570A and IBM personal computer. Connected with. Processing of the surface roughness data sent from Surfcom to the personal computer and its multi-resolution analysis calculation were performed by software created by the inventor in C language.

  Hereinafter, a configuration example of an electrophotographic photosensitive member using an electrophotographic photosensitive member substrate evaluated by the surface roughness evaluation method according to the present invention and an electrophotographic apparatus equipped with the electrophotographic photosensitive member will be described. The electrophotographic apparatus includes an electrophotographic process cartridge, which will be described later, in a narrow sense.

  FIG. 2 is a cross-sectional view schematically showing the layer structure of the electrophotographic photosensitive member. On the conductive electrophotographic photosensitive member base 21 (hereinafter also simply referred to as the base) 21, the charge is charged via the undercoat layer 22. A charge generation layer 23 mainly composed of a generation material and a charge transport layer 24 mainly composed of a charge transport material are stacked. Further, FIG. 3 shows a configuration in which a protective layer 25 is provided on the charge transport layer 24.

Examples of the conductive substrate (support) 21 are those having a volume resistance of 10 ¹⁰ Ωcm or less, for example, metals such as aluminum, nickel, chromium, nichrome, copper, gold, silver, and platinum, tin oxide, and indium oxide. Metal oxide such as film or cylindrical plastic or paper coated by vapor deposition or sputtering, or a plate of aluminum, aluminum alloy, nickel, stainless steel, etc. After pipe formation, pipes that have been surface-treated by cutting, superfinishing, polishing, or the like can be used. Further, an endless nickel belt and an endless stainless steel belt disclosed in Japanese Patent Publication No. 52-36016 can be used as the conductive substrate 21.

  In addition, the conductive base material 21 of the present invention can also be obtained by dispersing conductive powder on the base material and dispersing it in an appropriate binder resin. Examples of the conductive powder include carbon black, acetylene black, metal powder such as aluminum, nickel, iron, nichrome, copper, zinc, and silver, or metal oxide powder such as conductive tin oxide and ITO. It is done. The binder resin used at the same time is polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer. , Polyvinyl acetate, polyvinylidene chloride, polyarylate resin, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinylcarbazole, acrylic resin, silicone resin, epoxy resin, Examples thereof include thermoplastic, thermosetting resins, and photocurable resins such as melamine resin, urethane resin, phenol resin, and alkyd resin.

Such a conductive layer is formed by dispersing the conductive powder and the binder resin in a suitable solvent such as THF (tetrahydrofuran), MDC (dichloromethane), MEK (methyl ethyl ketone), toluene, and the like. Can be provided. Furthermore, it is electrically conductive by a heat shrinkable tube in which the conductive powder is contained in a material such as polyvinyl chloride, polypropylene, polyester, polystyrene, polyvinylidene chloride, polyethylene, chlorinated rubber, Teflon (registered trademark) on a suitable cylindrical substrate. Those provided with a conductive layer can also be used favorably as the conductive substrate 21 of the present invention.
As a processing method of the conductive substrate 21, various cutting processes, grinding processes, and polishing processes are possible, and a combination of these processing methods is also effective.

Next, the photosensitive layer will be described. The photosensitive layer may be a single layer or a laminated layer. For convenience of explanation, a case where the photosensitive layer is composed of the charge generation layer 23 and the charge transport layer 24 will be described first.
The charge generation layer 23 is a layer mainly composed of a charge generation material. As the charge generation material, organic materials such as pigments and dyes are used. As typical examples, monoazo pigments, disazo pigments, trisazo pigments, perylene pigments, perinone pigments, quinacridone pigments, quinone condensed polycyclic compounds, Squalic acid dyes, phthalocyanine pigments, naphthalocyanine pigments, azulenium salt dyes and the like are used. The charge generation material may be used alone or in combination of two or more.

  Examples of the binder resin used for the charge generation layer 23 include polyamide, polyurethane, epoxy resin, polyketone, polycarbonate, silicone resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone, polystyrene, polysulfone, poly-N-vinylcarbazole, Examples include polyacrylamide, polyvinyl benzal, polyester, phenoxy resin, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyphenylene oxide, polyamide, polyvinyl pyridine, cellulose resin, casein, polyvinyl alcohol, and polyvinyl pyrrolidone. The amount of the binder resin is 20 to 200 parts by weight, preferably 50 to 150 parts by weight with respect to 100 parts by weight of the charge generation material.

  Examples of the solvent used here include isopropanol, acetone, methyl ethyl ketone, cyclohexanone, tetrahydrofuran, dioxane, ethyl cellosolve, ethyl acetate, methyl acetate, dichloromethane, dichloroethane, monochlorobenzene, cyclohexane, toluene, xylene, ligroin and the like. As a coating method for the coating solution, a dip coating method, spray coating, beat coating, nozzle coating, spinner coating, ring coating, or the like can be used. The film thickness of the charge generation layer 23 is suitably about 0.01 to 5 μm, preferably 0.1 to 2 μm.

  The charge transport layer 24 can be formed by dissolving or dispersing a charge transport material and a binder resin in a suitable solvent, and applying and drying the solution on the charge generation layer 23. Moreover, a plasticizer, a leveling agent, antioxidant, etc. can also be added as needed. As the leveling agent, silicone oils such as dimethyl silicone oil and methylphenyl silicone oil, and polymers or oligomers having a perfluoroalkyl group in the side chain are used, and the amount used is 0 to 1 weight with respect to the binder resin. % Is appropriate.

  Charge transport materials include hole transport materials and electron transport materials. Examples of the electron transport material include chloroanil, bromanyl, tetracyanoethylene, tetracyanoquinodimethane, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-fluorenone, 2, 4,5,7-tetranitroxanthone, 2,4,8-trinitrothioxanthone, 2,6,8-trinitro-4H-indeno [1,2-b] thiophen-4-one, 1,3,7- Examples thereof include electron-accepting substances such as trinitrodibenzothiophene-5,5-dioxide and benzoquinone derivatives.

  The hole transport materials include poly-N-carbazole and derivatives thereof, poly-γ-carbazolylethyl glutamate and derivatives thereof, pyrene-formaldehyde condensates and derivatives thereof, polyvinylpyrene, polyvinylphenanthrene, polysilane, oxazole derivatives, oxalates. Diazole derivatives, imidazole derivatives, monoarylamine derivatives, diarylamine derivatives, triarylamine derivatives, stilbene derivatives, α-phenylstilbene derivatives, benzidine derivatives, diarylmethane derivatives, triarylmethane derivatives, 9-styrylanthracene derivatives, pyrazoline derivatives , Divinylbenzene derivatives, hydrazone derivatives, indene derivatives, butadiene derivatives, pyrene derivatives, etc., other known materials such as bisstilbene derivatives, enamine derivatives, etc. Charge. These charge transport materials may be used alone or in combination of two or more.

  As the binder resin, polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, Polyvinylidene chloride, polyarylate, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyl toluene, poly-N-vinyl carbazole, acrylic resin, silicone resin, epoxy resin, melamine resin, urethane resin, Examples thereof include thermoplastic or thermosetting resins such as phenol resins and alkyd resins.

The amount of the charge transport material is appropriately 20 to 300 parts by weight, preferably 40 to 150 parts by weight with respect to 100 parts by weight of the binder resin. The thickness of the charge transport layer is preferably about 5 to 50 μm.
Examples of the solvent used here include tetrahydrofuran, dioxane, toluene, dichloromethane, monochlorobenzene, dichloroethane, cyclohexanone, methyl ethyl ketone, and acetone.

  In addition, a polymer charge transport material having a function as a charge transport material and a function of a binder resin is also preferably used for the charge transport layer. The charge transport layer composed of these polymer charge transport materials is excellent in wear resistance. A known material can be used as the polymer charge transporting material, but a polycarbonate containing a triarylamine structure in the main chain and / or side chain is preferably used. For example, polymer charge transport materials represented by the formulas (1) to (10) in JP-A No. 2000-103984 are favorably used.

  Further, a plasticizer or a leveling agent may be added to the charge transport layer 24. As the plasticizer, those used as general plasticizers such as dibutyl phthalate and dioctyl phthalate can be used as they are, and the amount used is suitably about 0 to 30% by weight with respect to the binder resin. As the leveling agent, silicone oils such as dimethyl silicone oil and methylphenyl silicone oil, and polymers or oligomers having a perfluoroalkyl group in the side chain are used, and the amount used is 0 to 1 weight with respect to the binder resin. % Is appropriate.

  As shown in FIG. 3, the electrophotographic photosensitive member may be provided with a protective layer 25 on the photosensitive layer for the purpose of protecting the photosensitive layer. Materials used for the protective layer 25 include ABS resin, ACS resin, olefin-vinyl monomer copolymer, chlorinated polyether, allyl resin, phenol resin, polyacetal, polyamide, polyamideimide, polyacrylate, polyallylsulfone, polybutylene. , Polybutylene terephthalate, polycarbonate, polyethersulfone, polyethylene, polyethylene terephthalate, polyimide, acrylic resin, polymethylpentene, polypropylene, polyphenylene oxide, polysulfone, polystyrene, AS resin, butadiene-styrene copolymer, polyurethane, polyvinyl chloride, Examples of the resin include polyvinylidene chloride and epoxy resin. In addition to the protective layer 25, for the purpose of improving wear resistance, fluorine resins such as polytetrafluoroethylene, silicone resins, and those obtained by dispersing inorganic materials such as titanium oxide, tin oxide, and potassium titanate in these resins, etc. Can be added.

  As a method for forming the protective layer 25, a normal coating method is employed. The thickness of the protective layer 25 is suitably about 0.1 to 7 μm. In addition to the above, a known material such as a-C or a-SiC formed by a vacuum thin film manufacturing method can also be used as the protective layer 25.

  In the electrophotographic photoreceptor, as shown in FIGS. 2 and 3, an undercoat layer 22 can be provided between the conductive substrate 21 and the photosensitive layers (23, 24). The undercoat layer 22 is generally composed mainly of a resin. However, considering that the photosensitive layer is coated with a solvent on these resins, the undercoat layer 22 is a resin having a high solvent resistance with respect to a general organic solvent. Is desirable. Examples of such resins include water-soluble resins such as polyvinyl alcohol, casein, and sodium polyacrylate, alcohol-soluble resins such as copolymer nylon and methoxymethylated nylon, polyurethane, melamine resin, phenol resin, alkyd-melamine resin, and epoxy. Examples thereof include curable resins that form a three-dimensional network structure such as resins.

Further, in order to prevent moire and reduce residual potential, the undercoat layer 22 may be added with metal oxide fine powders exemplified by titanium oxide, silica, alumina, zirconium oxide, tin oxide, indium oxide and the like. . These undercoat layers 22 can be formed using an appropriate solvent and coating method, as in the case of the photosensitive layer described above.
Furthermore, as the undercoat layer 22, a silane coupling agent, a titanium coupling agent, a chromium coupling agent, or the like can be used. In addition, the undercoat layer 22 is made of anodized Al ₂ O ₃ , organic materials such as polyparaxylylene (parylene), SiO ₂ , SnO ₂ , TiO ₂ , ITO, CeO _2, etc. What provided the inorganic substance with the vacuum thin film preparation method can also be used favorably. In addition, known ones can be used. The thickness of the undercoat layer 22 is suitably 0 to 5 μm.

  An intermediate layer may be provided between the photosensitive layer (23, 24) and the protective layer 25 in some cases. In the intermediate layer, a binder resin is generally used as a main component. Examples of these resins include polyamide, alcohol-soluble nylon, polyvinyl hydroxide butyral, polyvinyl butyral, and polyvinyl alcohol. As a method for forming the intermediate layer, a normal coating method is employed as described above. In addition, about 0.05-2 micrometers is suitable for the thickness of an intermediate | middle layer.

  Next, an electrophotographic apparatus equipped with the electrophotographic photosensitive member will be described. FIG. 4 is a schematic diagram schematically illustrating an example of the electrophotographic apparatus, and modifications as described below also belong to the category of the present invention. In the electrophotographic apparatus shown in FIG. 4, a charging mechanism 32, an exposure light source 33, a developing mechanism 34, a transfer mechanism 35, and a cleaning mechanism 37 are arranged around a drum-shaped electrophotographic photosensitive member 31. In the transfer mechanism 35, the toner is transferred to the transfer material 38 and is fixed by the fixing mechanism 36.

In the electrophotographic method using the above-described electrophotographic apparatus, the electrophotographic photosensitive member 31 rotates counterclockwise, is charged positively or negatively by the charging mechanism 32, and is electrostatically charged by exposure from the exposure light source 33. A latent image is formed on the electrophotographic photoreceptor 31.
For the charging mechanism 32, known charging means such as a corotron, a scorotron, a solid state charger (solid state charger), a charging roller and the like can be used. A general charger can be used for the transfer mechanism 35, but a combination of a transfer charger and a separation charger is effective.

  Further, as the light source used for the exposure light source 33 and the static elimination light source (not shown), a fluorescent lamp, tungsten lamp, halogen lamp, mercury lamp, sodium lamp, light emitting diode (LED), semiconductor laser (LD), electroluminescence A light emitting material such as (EL) can be used. Various types of filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a desired wavelength range. In addition to the configuration shown in FIG. 4, such a light source or the like is provided with a transfer process, a static elimination process, a cleaning process, a pre-exposure process, and the like using light irradiation together, so that light is irradiated onto the photoreceptor. Can also be used.

  When image exposure is performed by positively or negatively charging the photoconductor, a positive or negative electrostatic latent image is formed on the photoconductor. A positive image can be obtained by developing the toner with negatively or positively charged toner (detection fine particles), and a negative image can be obtained by developing the toner with a positively or negatively charged toner. For such development, a known method can be applied, and a known method is also used for the charge eliminating means.

  In this example, the conductive substrate is shown as a drum, but a sheet or endless belt can be used. As the pre-cleaning charger, known charging means such as a corotron, a scorotron, a solid charger (solid state charger), a charging roller and the like can be used. In addition, the above charging means can usually be used for the transfer charger and the separation charger. For the cleaning mechanism, a known brush such as a fur brush or a mag fur brush, or a polyurethane blade can be used.

  The image forming means represented by the electrophotographic apparatus as described above may be fixedly incorporated in an apparatus such as a copying apparatus, a facsimile machine, or a printer, but is incorporated in the apparatus in the form of a process cartridge. May be. A process cartridge is a single device (part) that contains a photosensitive member, and further includes a charging means, an exposure means, a developing means, a transfer means, a cleaning means, a static elimination means, and the like. There are many shapes and the like of the process cartridge, but a general example is shown in FIG.

FIG. 5 shows an electrophotographic process cartridge. In FIG. 5, 31 is an electrophotographic photosensitive member, 32 is a charging means, 33 is an image exposure light source, 34 is a developing means, 35 is a transfer means, 38 is a transfer material such as paper, 36 is a fixing mechanism, 37 is a cleaning mechanism, Reference numeral 39 denotes a process cartridge container.
This figure shows an example of the structure, and each means may have a form other than that shown in the figure. For example, the charging unit 32 may be a known charging unit such as a corotron, a scorotron, or a charging roll. Light sources such as fluorescent lamps, tungsten lamps, halogen lamps, mercury lamps, sodium lamps, light emitting diodes (LEDs), semiconductor lasers (LDs), and electroluminescence (ELs) are used as light sources for image exposure and pre-exposure light (not shown). Means can be used. In addition, various types of filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a predetermined wavelength range. The cleaning mechanism 37 may be performed only by a cleaning blade, or may be used in combination with a cleaning brush or a blade. In the process cartridge shown in FIG. 5, the cleaning means or the like may not be included in the process cartridge. Further, the light emitting means and transfer means which are not built in the drawing may be built in the process cartridge.

EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated in detail, this invention is not restrict | limited by an Example. All parts are parts by weight.
Example 1
First, an undercoat layer coating solution, a charge generation layer coating solution, a charge transport layer coating solution, and a protective layer coating solution for coating each coating layer of the electrophotographic photosensitive member are respectively described below. In this way, it was produced.
[Composition of undercoat layer coating solution]
The following materials were dispersed with a ball mill to prepare an undercoat layer coating solution.
・ Alkyd resin (Beccosol 1307-60-EL, manufactured by Dainippon Ink & Chemicals) 6 parts ・ Melamine resin (Super Becamine G-821-60, manufactured by Dainippon Ink & Chemicals) 4 parts ・ Titanium oxide 40 parts ・ Methyl ethyl ketone 50 Part

[Preparation of charge generation layer coating solution]
The following materials were dispersed with a ball mill to prepare a charge generation layer coating solution.
-Bisazo pigment of the following structural formula (I) 2.5 parts-Polyvinyl butyral (XYHL, manufactured by UCC) 0.5 part-Cyclohexanone 200 parts-Methyl ethyl ketone 80 parts

[Preparation of charge transport layer coating solution]
After dissolving the following materials, the mixture was filtered through a cotton filter having an average pore diameter of 1 μm to prepare a charge transport layer coating solution.
-10 parts of bisphenol Z polycarbonate (Panlite TS-2050, manufactured by Teijin Chemicals)-7 parts of charge transport material of the following structural formula (II)-100 parts of tetrahydrofuran-1% silicone oil (KF50-100CS, manufactured by Shin-Etsu Chemical Co., Ltd.) Tetrahydrofuran solution 1 part

[Preparation of protective layer coating solution]
・ Alumina oxide powder (average particle size: about 0.2 μm) 15 parts ・ Bisphenol Z polycarbonate (Panlite TS-2050, manufactured by Teijin Chemicals) 40 parts ・ Charge transport material of structural formula (II) 30 parts
・ 2000 parts of tetrahydrofuran ・ 600 parts of cyclohexanone

[Production of electrophotographic photosensitive member]
After washing and drying an aluminum tube having an outer diameter of 30 mm, a wall thickness of 0.9 mm, and a length of 340 mm, the undercoat layer coating solution previously prepared by dip coating is applied, and dried at 120 ° C. for 30 minutes to be thick. A subbing layer having a thickness of 3 μm was formed.
Next, the charge generation layer coating solution prepared above is put in a coating tank of a dip coating apparatus, dip coated, dried at 105 ° C. for 10 minutes, and a charge generation layer having a thickness of about 0.8 μm. Formed.
Next, the previously prepared charge transport layer coating solution is placed in the coating tank of the dip coating apparatus, dip coated, and dried at 120 ° C. for 20 minutes to form a charge transport layer having a thickness of about 28 μm. did.

The electrophotographic photoreceptor thus prepared was attached to the apparatus shown in FIG.
In FIG. 6, 40 is an electrophotographic photosensitive member to be spray coated and 41 is a jig for holding both ends of the electrophotographic photosensitive member, which can be rotated at a constant speed. 42 is a spray nozzle for performing spray coating, 43 is a coating liquid atomized by the spray nozzle, and 44 is a table to which the spray nozzle is attached. This is a rail installed parallel to the electrophotographic photoreceptor 40. 45 and is movable in the axial direction of the electrophotographic photosensitive member.
46 is a pipe for supplying a spray coating liquid, 47 is a pipe for supplying compressed air used for spray coating, 48 is a pipe for supplying compressed air for driving a valve for controlling the execution of spray coating, 49 Is a knob for adjusting the needle protrusion amount of the spray nozzle.
The protective layer coating solution was then spray-coated at a spray compression air pressure of 120,000 Pa and the position of the knob for adjusting the needle protrusion amount of the spray nozzle at 90 °.
In Example 1, the protective layer is the outermost surface layer.

[Measurement of surface roughness]
The surface shape of the electrophotographic photoreceptor thus obtained was measured with a Surfcom 570 manufactured by Tokyo Seimitsu.
Here, the measurement length was 12 mm, and the total number of sampling points was 30720. The measurement results are imported into a personal computer, and the first wavelet transform, 1/40 decimation processing for the lowest frequency component obtained by the program created by the inventor, and the second wavelet transform are performed. It was.
The center line average roughness Ra, the maximum height Rmax, and the ten-point average roughness Rz were determined for the first and second multiresolution analysis results obtained in this manner.
FIG. 7 shows the result calculated in this way.

In FIG. 7, the graph of FIG. 7 (a) is the original data obtained by surfcom measurement, and may be called a roughness curve or a cross-sectional curve.
Although there are 14 graphs in FIG. 7, the vertical axis is the displacement of the surface shape and the unit is μm. The horizontal axis is the length, and the measurement length is 12 mm although no scale is provided.
In the conventional surface roughness measurement, the center line average roughness Ra, the maximum height Rmax, Rz, and the like are obtained from only this data.
Also, the six graphs in FIG. 7B are the results of the first multi-resolution analysis. The graph at the top is the highest frequency component, and the graph at the bottom is the lowest frequency component. .

Here, the uppermost graph 101 in FIG. 7B is the highest frequency component of the first multi-resolution analysis result, which is called MRA1-HH in the present invention.
The graph 102 is a frequency component that is one lower than the highest frequency component of the first multi-resolution analysis result. In the present invention, this is called MRA1-HL.
The graph 103 is a frequency component that is two lower than the highest frequency component of the first multi-resolution analysis result. In the present invention, this is called MRA1-MH.
The graph 104 shows three frequency components lower than the highest frequency component of the first multi-resolution analysis result, and this is called MRA1-ML in the present invention.
The graph 105 shows four frequency components lower than the highest frequency component of the first multi-resolution analysis result, and this is called MRA1-LH in the present invention.
The graph 106 is the lowest frequency component of the first multi-resolution analysis result, and this is called MR1-LL in the present invention.

In the present invention, the graph of FIG. 7A is separated into six graphs of FIG. 7B according to the frequency, and FIG. 8 shows the frequency separation state.
In FIG. 8, the horizontal axis represents the number of irregularities appearing per 1 mm length when the irregular shape is a sine wave. In addition, the vertical axis indicates the ratio when each band is separated.
In FIG. 8, 121 is a band of the highest frequency component in the first multi-resolution analysis,
122 is a frequency component band one lower than the highest frequency component in the first multi-resolution analysis,
123 is a band of frequency components two lower than the highest frequency component in the first multi-resolution analysis,
124 is a band of three frequency components lower than the highest frequency component in the first multiresolution analysis,
125 is a band of four frequency components lower than the highest frequency component in the first multi-resolution analysis,
Reference numeral 126 denotes a band of the lowest frequency component in the first multi-resolution analysis.

If FIG. 8 is demonstrated in detail, it will show that all appear in the graph 126, when the number of unevenness | corrugations per mm is 20 or less.
For example, when the number of irregularities is 110 per 1 mm, it appears most strongly in the graph 124, and this appears in MRA1-ML in FIG.
In addition, when the number of irregularities is 220 per 1 mm, it appears most strongly in the graph 123, which indicates that it appears in MRA1-MH in FIG. 7B.
Further, when the number of irregularities is 310 per mm, it appears in the graphs 122 and 123, and this shows that it appears in both MRA1-HL and MRA-MH in FIG. 7B.
Therefore, the frequency of the surface roughness determines where it appears on the six graphs in FIG. 7B.
In other words, in terms of surface roughness, fine roughness appears in the upper graph in FIG. 7B, and large surface waviness appears in the lower graph in FIG. 7B.

In the present invention, the surface roughness is thus decomposed by the frequency. FIG. 7B is a graph showing this, and the surface roughness in each frequency band is obtained from the graph for each frequency band. Here, as the surface roughness, it is possible to calculate the center line average roughness Ra, the maximum height Rmax, and the ten-point average roughness Rz.
In this way, in FIG. 7B, the center line average roughness Ra, the maximum height Rmax, and the ten-point average roughness Rz are numerically shown in the respective graphs.

In the present invention, since the data measured by the surface roughness meter is separated into a plurality of data according to the frequency, the unevenness change amount in each frequency band can be measured.
In the present invention, the lowest frequency, that is, MRA1-LL data is thinned out from the data separated as shown in FIG.
In the present invention, it is only necessary to determine how thinning is performed, that is, how many pieces of data are to be extracted, and it is possible to optimize frequency band separation in the multi-resolution analysis shown in FIG. 8 by optimizing the thinning number. This makes it possible to set the target frequency at the center of the band.
In Example 1, thinning was performed by taking one piece of data from 40 pieces.
The thinned result is shown in FIG. In FIG. 9, the vertical axis represents surface irregularities, and the unit is μm. Moreover, although the scale is not attached to the horizontal axis, the length is 12 mm.

In the present invention, the data of FIG. 9 is further subjected to multiresolution analysis. That is, the second multi-resolution analysis is performed.
The six graphs in FIG. 7C are the results of the second multi-resolution analysis, and the graph 107 at the top is the highest frequency component of the second multi-resolution analysis result, which is MRA2-HH. Call.
The graph 108 is a frequency component one lower than the highest frequency component of the second multi-resolution analysis result, and this is called MRA2-HL.
The graph 109 is a frequency component that is two lower than the highest frequency component of the second multi-resolution analysis result, and this is called MRA2-MH.
The graph 110 shows three lower frequency components than the highest frequency component of the second multi-resolution analysis result, and this is called MRA2-ML.
The graph 111 shows four frequency components lower than the highest frequency component of the second multi-resolution analysis result, and this is called MRA2-LH.
The graph 112 is the lowest frequency component of the second multi-resolution analysis result, and this is called MR2-LL.

In the present invention, in FIG. 7C, the graph is separated into six graphs according to the frequency. FIG. 10 shows the state of the frequency separation.
In FIG. 10, the horizontal axis represents the number of irregularities appearing per 1 mm length when the irregular shape is a sine wave. In addition, the vertical axis indicates the ratio when each band is separated.
In FIG. 10, 127 is the band of the highest frequency component in the second multiresolution analysis,
128 is a frequency component band one lower than the highest frequency component in the second multi-resolution analysis,
129 is a band of frequency components two lower than the highest frequency component in the second multi-resolution analysis,
130 is a band of three frequency components lower than the highest frequency component in the second multi-resolution analysis,
131 is a band of four frequency components lower than the highest frequency component in the second multiresolution analysis,
Reference numeral 132 denotes a band of the lowest frequency component in the second multi-resolution analysis.

10 will be described in more detail. When the number of irregularities per 1 mm is 0.2 or less, all appear in the graph 132.
For example, when the number of irregularities is 11 per mm, the graph 128 is the highest, but this shows that it appears most strongly in the frequency component band one lower than the highest frequency component in the second multiresolution analysis. In FIG. 7C, it appears that it appears in MRA2-ML.
Therefore, the frequency of the surface roughness determines where it appears in the six graphs of FIG.
In other words, in the surface roughness, fine roughness appears in the upper graph in FIG. 7C, and large surface waviness appears in the lower graph in FIG. 7C.
In the present invention, the surface roughness is thus decomposed by the frequency. FIG. 7C is a graph showing this, and the surface roughness in each frequency band is obtained from the graph for each frequency band. Here, as the surface roughness, it is possible to calculate the center line average roughness Ra, the maximum height Rmax, and the ten-point average roughness Rz.

  Multiplexing that separates the one-dimensional data array obtained by measuring the surface roughness of the electrophotographic photosensitive member with a surface roughness meter into a plurality of frequency components from a high frequency component to a low frequency component by wavelet transform. A resolution analysis is performed, and further, a one-dimensional data array in which the lowest frequency component obtained here is thinned out is created, and a wavelet transform is further performed on the one-dimensional data array, so that a plurality of components from a high frequency component to a low frequency component are obtained. Table 1 shows the results of performing multi-resolution analysis for separating frequency components, and determining the center line average roughness Ra, the maximum height Rmax, and the ten-point average roughness Rz for each frequency component obtained.

The graph of FIG. 7D is a surface shape estimated from the fourth and fifth from the top of the six frequency components of the second multiresolution analysis result. The graph shows the centerline average roughness Ra and the maximum height. Rmax and ten-point average roughness Rz are indicated by numerical values.
The numerical values are shown below.
Centerline average roughness Ra: 0.0848
Maximum height Rmax: 0.4125
Ten-point average roughness Rz: 0.3557
The surface shape obtained in this way is the surface shape when an arbitrary frequency is removed, and the surface shape may be evaluated with this value.

(Example 2)
As the spray coating conditions for the outermost layer, the spray compression air pressure was 150,000 Pa, the position of the knob for adjusting the needle protrusion amount of the spray nozzle was 120 °, and the protective layer coating solution was spray coated, as in Example 1. Thus, an electrophotographic photosensitive member was produced.
This is the electrophotographic photoreceptor of Example 2.
The surface roughness of the electrophotographic photosensitive member of Example 2 was measured in the same manner as in Example 1.
The measurement results are shown in FIG.
Similar to FIG. 7, in FIG. 11, the graph of FIG. 11 (a) is the original data obtained by surfcom measurement, and may be called a roughness curve or a cross-sectional curve.
In addition, the six graphs in FIG. 11B are the first multiresolution analysis results. The graph at the top is the highest frequency component, and the graph at the bottom is the lowest frequency component. .
In each graph, the center line average roughness Ra, the maximum height Rmax, and the ten-point average roughness Rz are indicated by numerical values. The numerical values are shown in Table 2.

The six graphs in FIG. 11C are the results of the second multi-resolution analysis. The graph at the top is the highest frequency component and the graph at the bottom is the lowest frequency component graph.
The graph of FIG. 11D is the surface shape estimated from the fourth and fifth from the top of the six frequency components of the second multiresolution analysis result. The graph shows the centerline average roughness Ra and the maximum height. Rmax and ten-point average roughness Rz are indicated by numerical values.
The numerical values are shown below.
Centerline average roughness Ra: 0.1373
Maximum height Rmax: 0.8466
Ten-point average roughness Rz: 0.6214

(Comparative Example 1)
The surface roughness of the electrophotographic photosensitive member of Example 1 was measured with Surfcom 570 manufactured by Tokyo Seimitsu, and the center line average roughness Ra, the maximum height Rmax, and the ten-point average roughness Rz were determined. At this time, the measurement reference length was 12 mm.
The measurement results of Comparative Example 1 are shown below.
Centerline average roughness Ra: 0.2051
Maximum height Rmax: 1.0204
Ten-point average roughness Rz: 0.9763

(Comparative Example 2)
The surface roughness of the electrophotographic photosensitive member of Example 2 was measured with Surfcom 570 manufactured by Tokyo Seimitsu, and the center line average roughness Ra, the maximum height Rmax, and the ten-point average roughness Rz were determined. At this time, the measurement reference length was 12 mm.
The measurement results of Comparative Example 2 are shown below.
Centerline average roughness Ra: 0.5213
Maximum height Rmax: 2.1771
Ten-point average roughness Rz: 1.5218

[Contrast between Example and Comparative Example]
According to the present invention, the one-dimensional data array obtained by measuring the uneven shape of the electrophotographic photosensitive member surface with a surface roughness meter is separated into a plurality of frequency components from a high frequency component to a low frequency component by wavelet transform. A multi-resolution analysis is performed, and a one-dimensional data array is created by thinning out the lowest frequency component obtained here, and wavelet transform is further performed on the one-dimensional data array to reach from a high frequency component to a low frequency component. A multi-resolution analysis that separates into a plurality of frequency components is performed, and center line average roughness Ra, maximum height Rmax, and ten-point average roughness Rz are obtained for each obtained frequency component. It is possible to know the state of the component, and more detailed results can be obtained unlike simply calculating the center line average roughness Ra, the maximum height Rmax, and the ten-point average roughness Rz. .
This will be described below.

The measurement results of Example 1 and Comparative Example 1 are collectively shown in Table 3.
The center line average roughness Ra, the maximum height Rmax, and the ten-point average roughness Rz obtained in Comparative Example 1 are values of all the unevenness frequencies, but in Example 1, the unevenness band, that is, the unevenness with large unevenness is large. The centerline average roughness Ra, the maximum height Rmax, and the ten-point average roughness Rz can be obtained. For example, MRA1-LL has the largest centerline average roughness Ra. From the result of multi-resolution analysis, it can be seen that the center line average roughness Ra of the lowest frequency component is large.
However, this was not found in the comparative example, and therefore the effect of the present invention could be confirmed.
Similarly, the measurement results of Example 2 and Comparative Example 2 are collectively shown in Table 4, and it can be seen from this result that the surface roughness can be separated and analyzed according to the present invention.

Furthermore, another comparison between Example 2 and Comparative Example 2 is performed using FIG.
FIG. 12 is an enlarged view showing a part of the result of Example 2 shown in FIG. In FIG. 12, (a) shows data measured by a surface roughness meter, (c) shows a part of the result of two times of multi-resolution analysis based on the present invention, and graph 110 shows frequency component MRA2. -ML, graph 111 below is frequency component MRA2-LH, and graph 112 at the bottom is frequency component MR2-LL.

A large recess 133 is recognized in the graph (a) of FIG. 12, and when the surface roughness Ra, the maximum height Rmax, Rz, etc. are calculated by the conventional method, the value is influenced by this large recess.
However, looking at FIG. 12C, which is the result of analysis according to the present invention, the large recess 133 is separated as the large recess 134 in the graph 112 of FIG. 12, and other than the graph 112 of FIG. 110 does not appear in the graph 111.
Therefore, when the surface roughness is obtained based on the graph 110 or the graph 111, it can be seen that the surface roughness can be measured without being affected by the large concave 133 in the original data. Further, when the surface roughness is obtained from the graph 112, the size of the large recess 134 can be known.
This was not possible with the conventional surface roughness measurement method, and therefore the effect of the present invention could be confirmed.

Further, the effect of the present invention is shown in FIG.
FIG. 13 shows the centerline average roughness Ra measurement result obtained in Example 1 and the centerline average roughness Ra measurement result obtained in Example 2. The horizontal axis represents the number of sine wave irregularities per mm, and the vertical axis represents the second time. The surface roughness centerline average roughness Ra obtained from the multi-resolution analysis results is shown in a semi-logarithmic graph.
Referring to FIG. 13, it can be seen that the center line average roughness Ra of the sample 1 and the sample 2 shows in each frequency band. However, the value obtained by the conventional surface roughness measurement method is only one numerical value, and it has not been understood what frequency the surface unevenness has.
This was not possible with the conventional surface roughness measurement method, and therefore the effect of the present invention could be confirmed.
Although the surface roughness centerline average roughness Ra is shown in FIG. 13, it can be graphed by the maximum height Rmax or Rz.

  According to the surface shape evaluation method of the present invention, since the surface state of the measurement object can be evaluated in more detail, the transfer roller including the electrophotographic photosensitive member whose transfer surface needs to be roughened, the transfer It is suitable for evaluating the surface shape of electrophotographic apparatus parts such as a belt, a fixing roller, a fixing belt, a conveying roller, and a conveying belt.

Configuration diagram of a surface roughness evaluation system suitable for carrying out the present invention Diagram of layer structure of electrophotographic photoreceptor Illustration of another layer structure of electrophotographic photosensitive member Configuration diagram of an electrophotographic apparatus Configuration diagram of process cartridge for electrophotographic equipment Spray coating equipment Measurement result of Example 1 Illustration of frequency band separation in the first multi-resolution analysis Graph of the lowest frequency data in the first multi-resolution analysis Diagram of frequency band separation in the second multiresolution analysis The figure which shows the measurement result of Example 2 Partial enlarged view of the measurement result of Example 2 The figure which showed the measurement result of Example 1 and Example 2 by the semilogarithmic graph

Explanation of symbols

1 Electrophotographic photoconductor to be measured
2 Jig with a probe for measuring surface roughness
3 Mechanism to move the jig along the measurement target
4 Surface roughness meter
5 Personal computer for signal analysis
21 Substrate for electrophotographic photosensitive member
22 Underlayer
23 Charge generation layer
24 Charge transport layer
25 Protective layer
31 Electrophotographic photoreceptor
32 Charging mechanism
33 Exposure light source
34 Development mechanism
35 Transcription mechanism
36 Fixing mechanism
37 Cleaning mechanism
38 Transfer material
39 Process cartridge case 40 Electrophotographic photosensitive member 41 for spray coating 41 Jig 42 for holding both ends of the electrophotographic photosensitive member Spray nozzle 43 for spray coating Coating liquid 44 atomized by spray nozzle Mounted base 45 Rail moving on the base where the spray nozzle is mounted 46 Pipe for supplying spray coating liquid 47 Pipe for supplying compressed air used for spray coating 48 Compression for driving a valve for controlling the execution of spray coating Pipe 49 for supplying air Knob 101 for adjusting the needle protrusion amount of the spray nozzle The highest frequency component 102 of the first multi-resolution analysis result The frequency component 103 one lower than the highest frequency component of the first multi-resolution analysis result The first time Frequency component 104 that is two lower than the highest frequency component of the multi-resolution analysis result The frequency component 105 that is three lower than the highest frequency component of the first multi-resolution analysis result The frequency component 106 that is four times lower than the highest frequency component of the first multi-resolution analysis result 106 The lowest frequency component 107 of the first multi-resolution analysis result The highest frequency component of the multiresolution analysis result 108 The frequency component one lower than the highest frequency component of the second multiresolution analysis result 109 The frequency component two lower than the highest frequency component of the second multiresolution analysis result 110 The second multiresolution 3 frequency components lower than the highest frequency component of the analysis result 111 4 frequency components lower than the highest frequency component of the second multi-resolution analysis result 112 lowest frequency component of the second multi-resolution analysis result 121 In the first multi-resolution analysis Highest frequency component band 122 Highest frequency component in the first multi-resolution analysis A frequency component band 123 that is one frequency lower than the highest frequency component in the first multi-resolution analysis 124 A frequency component band 124 that is three times lower than the highest frequency component in the first multi-resolution analysis Band 126 of frequency component four lower than highest frequency component in multi-resolution analysis First lowest frequency component band 127 in first multi-resolution analysis First highest frequency component band 128 in second multi-resolution analysis Second highest multi-resolution analysis A frequency component band 129 one lower than the high frequency component 129 A frequency component band 130 lower than the highest frequency component in the second multi-resolution analysis 130 A frequency component band 131 2 lower than the highest frequency component in the second multi-resolution analysis Four frequency components lower than the highest frequency component in the second multi-resolution analysis Band of the lowest frequency components in the band 132 second multiresolution analysis

Claims (4)

Multi-resolution analysis that separates the one-dimensional data array obtained by measuring the surface roughness of electrophotographic parts with a surface roughness meter into multiple frequency components from high frequency components to low frequency components by wavelet transform Furthermore, a one-dimensional data array is created by thinning out the lowest frequency component obtained here so that the number of data arrays is reduced to 1/10 to 1/100, and wavelet transform is further performed on this one-dimensional data array. And performing a multi-resolution analysis to separate a plurality of frequency components from a high frequency component to a low frequency component, and for each frequency component obtained, centerline average roughness Ra, maximum height Rmax, ten-point average roughness A method for evaluating the surface shape of a part for an electrophotographic apparatus, wherein the thickness Rz is obtained.   2. The surface shape evaluation method according to claim 1, wherein the electrophotographic apparatus component is an electrophotographic photosensitive member.   2. The surface shape evaluation method according to claim 1, wherein the electrophotographic apparatus component is a kind selected from a transfer roller, a transfer belt, a fixing roller, a fixing belt, a conveyance roller, and a conveyance belt.   4. The surface shape evaluation method according to claim 1, wherein the first multi-resolution analysis and the second multi-resolution analysis are performed for four or more frequency components.

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