JP2006077372A - Conductive fabric and brush comprising the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conductive fabric which is produced by plying or mix-weaving conductive multifilaments and conductive multifilaments having a different single filament fineness, used for electrophotographic recording type dry copying machines, facsimiles, printers and the like, and to provide a brush which comprises the conductive fabric and has both effects of high image quality due to a high pile density and improved cleanability by giving good tension and stiffness to piles. <P>SOLUTION: This conductive fabric comprising conductive multifilaments (A) and conductive multifilaments (B) having different single filament fineness is characterized by plying or mix-weaving the conductive multifilaments (A) and the conductive multifilaments (B). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a conductive fabric used for a charging brush and a cleaner brush used in an electrophotographic recording type dry copying machine, a facsimile, a printer, and the like. Further, the present invention relates to a charging brush and a cleaner brush in which the conductive fabric is used in an electrophotographic recording type dry copying machine, a facsimile, a printer, and the like.

Fibers used for developing brushes, contact charging brushes, and photosensitive drum cleaner brushes used in electrophotographic recording type dry copying machines, facsimiles, printers, etc. are required to have a specific resistance of 10 ⁰ to 10 ⁸ Ωcm. Has been. Conventionally, as described in Patent Documents 1 to 3, multifilaments containing conductive carbon fine particles in such applications have used cellulosic fibers and vinylon conductive yarns. Conventionally, cellulosic fibers and vinylon conductive yarns have a single yarn fineness of about 4 to 5 dtex, and the conductive yarn pile density when weaving is about 30,000 / inch ^{2 in} order to further improve image quality. A high pile density is desired when weaving. In addition, as a method for increasing the pile density, the fineness of single yarn fineness has been studied in recent years, but when used as a charging brush, good image quality is obtained, but as a brush for both charging and cleaning When it is used, there is a problem that the peel of the pile is lowered, and the toner remaining on the photosensitive member cannot be sufficiently removed to deteriorate the image quality.
JP-A-9-491117 (paragraph [0007]) JP 2000-355823 A (paragraphs [0002] to [0003]) Japanese Unexamined Patent Publication No. 2000-160427 (paragraph [0003])

  Accordingly, the present invention relates to a conductive cloth having conductivity and a brush comprising the same used in electrophotographic recording type dry copying machines, facsimiles, printers, etc., and conductive multifilaments having different single yarn finenesses are twisted or twisted. It is an object of the present invention to achieve both effects of high image quality due to high pile density by using a cloth by union weaving and an effect of improving the cleaning property by giving the pile a firmness in the same brush.

In order to solve the above-described problems, the conductive heterogeneity mixed yarn of the present invention mainly has the following configuration. That is,
(1) A conductive fabric comprising a conductive multifilament (A) and a conductive multifilament (B) having different single yarn fineness, wherein the conductive multifilament (A) and the conductive multifilament (B) are twisted or An electrically conductive fabric obtained by weaving,
(2) The ratio T (A) / T (B) of the single yarn fineness T (A) of the conductive multifilament (A) and the single yarn fineness T (B) of the conductive multifilament (B) is 1.5 to 8. The single yarn fineness T (A) of the conductive multifilament (A) is 2 to 8 dtex, the single yarn fineness T (B) of the conductive multifilament (B) is 1 to 5 dtex, and the conductive multifilament ( The ratio R (A) / R (B) of the specific resistance R (A) of A) and the specific resistance R (B) of the conductive multifilament (B) is 1.1 to 2, and the conductive multifilament (A) 2. The conductive fabric according to claim 1, wherein the specific resistance R (A) is 10 ^{4 to 10} Ωcm, and the specific resistance R (B) of the conductive multifilament (B) is 10 ^{5 to 12} Ωcm.
(3) A brush using the conductive fabric according to (1) or (2), and used as an electrification and cleaner brush in an electrophotographic recording type dry copying machine, facsimile, or printer. Features brush,
It is.

  The present invention is a conductive fabric composed of conductive multifilaments having different single yarn finenesses. By forming the conductive multifilaments having different single yarn finenesses by twisting or weaving, the fineness yarns contribute to an increase in pile density. The image quality is improved, and the thick fine yarn gives the pile a firmness and improves the cleaning performance. The conductive fabric of the present invention is a charging and cleaner brush used in electrophotographic recording type dry copying machines, facsimiles, printers, etc. It is particularly suitable for.

  The conductive fabric of the present invention is formed by twisting or interweaving conductive multifilament (A) and conductive multifilament (B) having different single yarn fineness.

  Twisting is a method of bundling two types of conductive multifilaments, conductive multifilament (A) and conductive multifilament (B), using a twist twister or double twister, etc. The multifilament of the book. The cross-weaving means that when conducting warping to make a conductive fabric, the warp is made by alternately conducting the conductive multifilament (A) and the conductive conductive multifilament (B) to form a woven fabric and a conductive fabric. is there. As the conductive multifilament, any combination such as polyolefin such as rayon, vinylon, polyamide, polyester, acrylic, polyethylene, polypropylene and the like may be used.

  Ratio T (A) / T (B) of the single yarn fineness T (A) of the conductive multifilament (A) of the conductive fabric of the present invention and the single yarn fineness T (B) of the conductive multifilament (B) ( Hereinafter, the single yarn fineness ratio) is 1.5-8. When the single yarn fineness ratio is less than 1.5, the conductive multifilament (A) and the conductive multifilament (B) are twisted or woven together to produce a brush. As a result, it is difficult to remove the toner sufficiently, the cleaning property is deteriorated, and the image quality is deteriorated when used for a long time. Problems such as a decrease in density and a decrease in resolution of a printed image occur. When the single yarn fineness ratio exceeds 8, the single yarn (A) gives sufficient pile strength to the pile, but the pile density is lowered and high-quality printing cannot be obtained. In addition, the pile becomes hard and may cause scratches on the photoreceptor. The single yarn fineness is the fineness of individual single yarns constituting the multifilament, and is represented by the weight (g) of individual values of single yarn per 10,000 m. The method for measuring the single yarn fineness can be calculated using a denier computer.

  The single yarn fineness T (A) of the conductive multifilament (A) constituting the conductive fabric of the present invention is 2 to 8 dtex (decitex), and the single yarn fineness T (B) of the conductive multifilament (B) is 1 to 1. 5 dtex (decitex). If the single yarn fineness T (A) is less than 2 dtex (decitex), the pile cannot be given sufficient elasticity, and the cleaning property is deteriorated, and the image quality is deteriorated when used for a long time. On the other hand, when the single yarn fineness exceeds 8 dtex (decitex), the pile becomes hard, which causes a scratch on the photosensitive member on the upper part of the brush. If the single yarn fineness T (B) is less than 1 dtex (decitex), the single yarn becomes too thin, and yarn breakage during yarn production, single breakage in the drawing process, and fluff are likely to occur, and stable productivity cannot be obtained. On the other hand, if the single yarn fineness exceeds 5 dtex (decitex), the pile density when the brush is prepared is lowered, and the resolution of the printed image is deteriorated.

  The conductive fabric of the present invention has a ratio R (A) / R (B) (hereinafter referred to as a specific resistance R (A) of the conductive multifilament (A) and a specific resistance R (B) of the conductive multifilament (B). The specific resistance ratio) is 1.1-2. A logarithmic value is used as the specific resistance value at this time. When the specific resistance ratio is less than 1.1, since the conductive multifilament (A) and the conductive multifilament (B) having different single yarn fineness are charged to the photoconductor, the charge density to the photoconductor is increased. Unevenness occurs, and the resolution of the printed image becomes worse when the image is formed.

The conductive fabric of the present invention has a specific resistance R (A) of the conductive multifilament (A) of 10 ^{5 to 12} Ωcm, and a specific resistance R (B) of the conductive multifilament (B) of 10 ^{4 to 10} Ωcm. . When the specific resistance R (A) of the conductive multifilament (A) is less than 10 ⁵ Ωcm, when the conductive multifilament (A) and the conductive multifilament ( Since the photosensitive member is charged from both of B), there is a problem that the charge density on the photosensitive member becomes uneven. Further, when the specific resistance R (A) of the conductive multifilament (A) exceeds 10 ¹² Ωcm, there is a problem that charges and toner remaining on the photoreceptor cannot be sufficiently removed.

If the specific resistance R (B) of the conductive multifilament (B) is less than 10 ⁴ Ωcm, there is a problem that current is passed between the adjacent conductive multifilaments and pinholes on the surface of the photoreceptor due to plasma discharge occur. Further, when the specific resistance R (A) of the conductive multifilament (A) exceeds 10 ¹⁰ Ωcm, there is a problem that the photosensitive member cannot be charged and printing cannot be performed.

  The electrophotographic recording type dry copying machine brush using the conductive fabric of the present invention is an application brush that contacts and charges the photosensitive member in place of non-contact corona discharge, and removes charge and toner remaining on the photosensitive member. Cleaning brush, charging and cleaning brush having charging and cleaning performance.

  The conductive fabric and brush of the present invention are produced by the following method.

  Conductive multifilament (A) and conductive multifilament (B) are used as conductive multifilaments having the above characteristics, and these two types of conductive multifilaments are twisted at 150 t / m using a draw twister. After weaving so that the pile density is 1000 / inch and the pile length is 7 mm, the pile is finished. Next, after the pile is cut into a tape shape having a width of 10 to 30 mm, the pile is spirally wound around the cylindrical surface of a columnar metal bar to create a brush. The brush can also be manufactured by simply attaching the pile to the plate.

  The conductive fabric of the present invention includes electrophotographic recording type dry copying machines, facsimiles, printers, and the like.

Hereinafter, the present invention will be described in detail with reference to examples. The evaluation method is as follows.

A. Specific resistance value The conductive yarn wound by stretching is cut into a sample length of 10 cm and fixed to an acrylic plate. Subsequently, using a super insulation resistance meter (TERAOHMMETER R-503, manufactured by Kawaguchi Electric Co., Ltd.), a voltage of 100 (V) was applied to measure the electrical resistance value (Ω / cm) under the conditions of a temperature of 20 ° C. and a humidity of 30% RH. Then, it was calculated from the following formula (1) (measurement was performed 10 times and the average value was calculated). Table 1 shows the logarithmic value log ₁₀ (RS / Ωcm) of the specific resistance RS.
RS = R × D / (10 × L × SG) × 10 ⁻⁵ (1)
RS: Specific resistance (Ωcm)
R: Electric resistance value (Ω)
D: Yarn weight per 10000 m (g)
L: Test length (cm)
SG: Yarn density (g / cm ³ ).

B. Image quality The brush is incorporated into the copier as a charging brush and cleaner brush, and a test chart (No1R) issued by the Electrophotographic Society is copied. An average of 7 or more was regarded as a passing level.

C. Changes in image quality during long-term use Compare the image quality of the test chart issued by the Electrophotographic Society with the first copy and the one after 20,000 copies, and perform sensory evaluation on 10 people according to the following criteria It was.
2 points: No difference 1 point: Some differences are seen 0 points: Differences are seen Based on the total score of 10 people, classification was made according to the following criteria.
：: 18 to 20 points ○: 15 to 17 points Δ: 10 to 14 points ×: 0 to 9 points.

D. Single yarn fineness measurement method Using a motorcycle blow type fineness measuring device (Denier Computer) manufactured by Search Corporation, the measurement sample length is 50 mm, and the load is the measurement sample fineness (denier equivalent) x 0.1 g. After confirming that the vibration frequency was stabilized by applying vibration, the total number of filaments of the measurement sample was measured and evaluated.

Example 1
Nylon 6 filament of 170 dtex 28 filament was used as the conductive multifilament (A). The conductive multifilament (A) had a single yarn fineness T (A) of 6 dtex and a specific resistance value R (A) of 10 ⁸ Ωcm. Further, nylon 6 filament of 170 dtex 113 filament was used as the conductive multifilament (B). This conductive multifilament (B) had a single yarn fineness T (B) of 1.5 dtex and a specific resistance value R (B) of 10 ⁶ Ωcm. By using these two types of conductive multifilaments, the single yarn fineness ratio T (A) / T (B) was set to 4, and the specific resistance ratio R (A) / R (B) was set to 1.3. These two types of conductive multifilaments were twisted at 150 t / m using a draw twister and woven so that the pile density was 1000 pieces / inch and the pile length was 7 mm, and then the pile was finished. Next, after making the pile into a tape with a width of 15 mm, create a brush by spirally winding it on a cylindrical surface with a diameter of 6 mm, and attach the created brush to the copier to investigate changes in image quality and image quality during long-term use. went. As a result, the image quality was 8, and the image quality during long-term use was ◎.

Example 2
Nylon 6 filament of 170 dtex 28 filament was used as the conductive multifilament (A). The conductive multifilament (A) had a single yarn fineness T (A) of 6 dtex and a specific resistance value R (A) of 10 ⁸ Ωcm. Further, nylon 6 filament of 170 dtex 113 filament was used as the conductive multifilament (B). This conductive multifilament (B) had a single yarn fineness T (B) of 1.5 dtex and a specific resistance value R (B) of 10 ⁶ Ωcm. By using these two types of conductive multifilaments, the single yarn fineness ratio T (A) / T (B) was set to 4, and the specific resistance ratio R (A) / R (B) was set to 1.3. These two kinds of conductive multifilaments were interwoven so that the pile density was 1000 / inch and the pile length was 7 mm, and then the pile was finished. Next, after making the pile into a tape with a width of 15 mm, create a brush by spirally winding it on a cylindrical surface with a diameter of 6 mm, and attach the created brush to the copier to investigate changes in image quality and image quality during long-term use. went. As a result, the image quality was 8, and the image quality during long-term use was ◎.

Example 3
As the conductive multifilament (A), a 170 dtex 28 filament rayon multifilament was used. The conductive multifilament (A) had a single yarn fineness T (A) of 6 dtex and a specific resistance value R (A) of 10 ⁶ Ωcm. Further, as the conductive multifilament (B), Iron 6 filament of 170 dtex 113 filament was used. This conductive multifilament (B) had a single yarn fineness T (B) of 1.5 dtex and a specific resistance value R (B) of 10 ⁵ Ωcm. By using these two types of conductive multifilaments, the single yarn fineness ratio T (A) / T (B) was set to 4, and the specific resistance ratio R (A) / R (B) was set to 1.2. These two types of conductive multifilaments were twisted at 150 t / m using a draw twister and woven so that the pile density was 1000 pieces / inch and the pile length was 7 mm, and then the pile was finished. Next, after making the pile into a tape with a width of 15 mm, create a brush by spirally winding it on a cylindrical surface with a diameter of 6 mm, and attach the created brush to the copier to investigate changes in image quality and image quality during long-term use. went. As a result, the image quality was 9, and the image quality after long-term use was ◎.

Comparative Example 1
Nylon 6 filament of 170 dtex 28 filament was used as the conductive multifilament (A). The conductive multifilament (A) had a single yarn fineness T (A) of 6 dtex and a specific resistance value R (A) of 10 ⁸ Ωcm. The conductive multifilament (A) was woven so that the pile density was 1000 / inch and the pile length was 7 mm, and then the pile was finished. Next, after making the pile into a tape with a width of 15 mm, create a brush by spirally winding it on a cylindrical surface with a diameter of 6 mm, and attach the created brush to the copier to investigate changes in image quality and image quality during long-term use. went. As a result, the image quality was 9, and the image quality during long-term use was x.

Comparative Example 1
Nylon 6 filament of 170 dtex 81 filament was used as the conductive multifilament (B). This conductive multifilament (B) had a single yarn fineness T (B) of 2.1 dtex and a specific resistance value R (B) of 10 ⁶ Ωcm. The conductive multifilament (B) was woven so that the pile density was 1000 / inch and the pile length was 7 mm, and then the pile was finished. Next, after making the pile into a tape with a width of 15 mm, create a brush by spirally winding it on a cylindrical surface with a diameter of 6 mm, and attach the created brush to the copier to investigate changes in image quality and image quality during long-term use. went. As a result, the image quality was 4, and the image quality during long-term use was ○.

  As is apparent from the results in Tables 1 and 2, the conductive heterogeneity mixed yarn and brush of the present invention have a very remarkable effect on high-quality printing of electrophotographic recording type dry copying machines, facsimiles, printers, and the like. I understand that.

Claims (3)

A conductive fabric comprising conductive multifilaments (A) and conductive multifilaments (B) having different single yarn fineness,
A conductive fabric obtained by twisting or interweaving a conductive multifilament (A) and a conductive multifilament (B). The ratio T (A) / T (B) of the single yarn fineness T (A) of the conductive multifilament (A) and the single yarn fineness T (B) of the conductive multifilament (B) is 1.5 to 8,
The single yarn fineness T (A) of the conductive multifilament (A) is 2 to 8 dtex, the single yarn fineness T (B) of the conductive multifilament (B) is 1 to 5 dtex,
And the ratio R (A) / R (B) of the specific resistance R (A) of the conductive multifilament (A) and the specific resistance R (B) of the conductive multifilament (B) is 1.1 to 2,
The specific resistance R (A) of the conductive multifilament (A) is 10 ^{4 to 10} Ωcm,
2. The conductive fabric according to claim 1, wherein the specific resistance R (B) of the conductive multifilament (B) is 10 ^{5 to 12} Ωcm. A brush using the conductive fabric according to claim 1 or 2, wherein the brush is used as a charging and cleaner brush in an electrophotographic recording type dry copying machine, a facsimile, or a printer.