JPS6167038A - Electrophotographic transfer paper - Google Patents

Abstract

PURPOSE:To prevent an abrasion of a photosensitive body by regulating a content of calcium carbonate of a filler to <=8wt% on the wt basis of the paper powder, thereby reducing calcium carbonate content in the paper powder. CONSTITUTION:A heavy calcium carbonate obtd. by grinding a limestone and a shell-chalk, and a precipitated calcium carbonate may be used as the calcium carbonate filler. The precipitated calcium carbonate is prepared according to a carbon dioxide combination method of reacting a milk of lime with carbon dioxide, a milk of lime-soda combination method and a calcium chloride combi nation method. If the compounding amount of calcium carbonate is insufficient to obtain a filler effect, another filler having less abrasion e.g. a talc and a kaolin-clay etc. may be used with calcium carbonate. And an alkylketene dimer and an alkenyl succinic anhydride are preferably used as an engine sizing agent.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrophotographic transfer paper used in electrophotographic copying machines, printers, and the like.

[Conventional technology]

Conventionally, as a transfer paper for electrophotography, Japanese Patent Application Laid-Open No. 54-187
As disclosed in Japanese Patent Publication No. 40 and Japanese Patent Application Laid-Open No. 54-22831, acidic paper containing fillers such as talc and kaolin clay is the mainstream, but in recent years, in the paper industry, We are applying the neutral papermaking technology that has been implemented in the fields of thin paper such as paper and rice paper, and special paper such as metal stand, rust prevention, electrical insulation, and photographic printing to the production of high-quality paper for printing and writing. There is a growing trend to apply it to the world.

This neutral paper is made by using an aqueous medium with a pH of 7.0 or higher, using a neutral size as a sizing agent, and mainly using calcium carbonate when mixing test samples. It is.

The main aim of converting this high-quality paper to neutral paper is to reduce paper manufacturing costs by using resource-rich and inexpensive carbonate as a filler, and to save energy and resources in paper manufacturing. The aim is to improve productivity, reduce equipment pollution, and purify wastewater.

[Problem that the invention seeks to solve]

However, this neutral high-quality paper, for example,
When neutral high-quality paper as shown in No. 36623 and Japanese Patent Application No. 58-64.598 is used as transfer paper for electrophotography, the wear of the photoreceptor becomes severe and the life of the photoreceptor is shortened. This has the disadvantage that it may cause the image to be blurred or the quality of the copied image may deteriorate.

This phenomenon of abrasion of the photoreceptor occurs noticeably in copiers and printers that use a blade method as the photoreceptor glue device. The rubber rolls, rubber healds, fixing rolls, etc. used in this process also wear out, resulting in disadvantages such as poor paper running properties and increased fusing failure.

[Means and effects for solving the problems] The present inventors have made extensive efforts to eliminate and improve the above-mentioned drawbacks of the prior art, and have found that the cause of the wear of the photoreceptor, etc. is the above-mentioned one. It was discovered that it was a carbonic acid compound contained in a neutral high-quality powder.

In other words, the above-mentioned carbonate powder has a relatively high hardness of 3 to 4 on the Mohs hardness compared to acid paper fillers such as Merck and kaolin clay, so this carbonate powder is used for cleaning as part of the paper powder component. It adhered to the tip of the plate and came into contact with the photoreceptor, abrading its surface.

Similarly, the abrasion of the rubber roll, rubber belt, fixing roll, etc. of the paper feeding device was also caused by the above-mentioned carbonic acid.

Therefore, the inventors of the present invention have found that the above-mentioned neutral high-quality paper is usually 10
The present invention has been completed based on the discovery that the above-mentioned drawbacks of the prior art can be overcome by reducing the amount of calcium carbonate that is blended in at least %.

That is, the present invention provides an electrophotographic transfer paper containing pulp cellulose, a sizing agent, and a filler as main components and using carbonate as the filler, in which the amount of the carbonate is 8 weight or less. (This reduces the content of carbonate in the paper powder, thereby significantly reducing the amount of carbonate that adheres to the photoreceptor, cleaning blade, rubber roller, etc.) and the fixing roll, resulting in wear and tear on the photoreceptor, etc. This is to prevent

Here, as the carbonate as the filler, heavy carbonate, which is obtained by crushing limestone, limestone, chalk, etc., and precipitated carbonate, can be used.

As a method for producing the above-mentioned precipitated calcium carbonate, a carbonation method in which milk of lime is reacted with carbon dioxide gas, a method of soda production of lime milk, and a method of production of calcium chloride can be used.

Furthermore, if the amount of calcium carbonate blended is too small to be effective as a filler, other less abrasive fillers such as talc or kaolin clay may also be used.

Further, as the internally added sizing agent, it is preferable to use an alkyl ketene dimer type or an alkenyl succinic anhydride type.

Furthermore, in producing the electrophotographic transfer paper of the present invention, the following raw materials are blended and prepared in order to impart properties suitable for electrophotography such as copyability, runnability, and curling properties. , the manufacturing conditions are controlled (Special Public Interest Publication Showa 4 ÷ -
No. 3673, Special Publication No. 4.6-24199, Special Publication No. 1973
- Hand No. 7385, JP-A-55-142799).

In other words, in order to maintain appropriate copy image density and prevent staining of the background (white paper area), sodium chloride,
The surface electrical resistance of the transfer paper (JISC-211
0C) to 10'~10''Ω (humidity (R, H,) 6
5 inches, temperature 20℃). In addition, in order to improve the sharpness of the copy image area, the surface unevenness is reduced and the smoothness of the transfer paper (JISP-8119 (Koyoru)) is maintained for at least 20 seconds.
Rub. In addition, if the transfer paper partially absorbs moisture and swells or curls, the closeness between the copying machine's photoreceptor and the transfer paper will decrease during transfer, resulting in a decrease in copy image density and partial omission of copies. 4. Remove moisture from paper to prevent
5 to 5.5% and packaged with moisture-proof wrapping paper to prevent moisture absorption and desorption during storage. Examples are shown below.

[Implementation) 2] Eight types of transfer papers (Examples 1 to 6) with the physical properties shown in Table 1 were made using a normal neutral paper making method using a Tatsu II filler, pulp cellulose, and a sizing agent. , specific soft columns 1-2) were produced.

In addition, a commercially available neutral high-quality paper was analyzed to obtain the data shown in Table 1, and this high-quality paper was used as comparison column 3.

Then, the nine types of transfer paper (Examples 1 to 6, Comparative Examples 1 to 3) described above were set in a cleaning blade type copying machine, and the degree of wear of the photoreceptor and the occurrence of black streaks, white spots, etc. due to each transfer paper were measured. We evaluated the effect of

The amount of carbonate in the transfer paper was determined using Tarapi (T).
appi) are shown in Table 1 according to the standard T4225U-67, and the particle size of the filler was measured by the sedimentation method in the raw material state (Examples 1 to 6, Comparative Examples 1 to 2),
On the other hand, when it was contained in paper (comparison row 3), it was disintegrated with water to obtain a sample, which was measured using a scanning electron microscope and is shown in Table 1.

Further, in Table 1, the filler composition indicates the weight percent in the transfer paper, and the pulp composition indicates the blending ratio of LBKP (broad-leaf bleached kraft pulp) and NBKP (softwood bleached kraft pulp).

Further, the degree of wear of the photoreceptor and the copy quality in Table 1 were evaluated using the following methods.

First, regarding the degree of wear of the photoreceptor, after running 5000 sheets each of nine types of transfer papers of Examples 1 to 6 and Comparative Examples 1 to 3 without toner development using the above-mentioned copying 4fi,
Paper dust adhering to the cleaning blade is collected and subjected to X-ray analysis (X-ray Photoele-ctro).
n 5pectroscooy) to check for the presence of photoreceptor components, and if no photoreceptor components are detected in the paper powder, f
This means that there is no wear on the photoreceptor, so ○.
If detected, it means that wear has occurred and was evaluated as x.

On the other hand, regarding the Cobby Act, after running 10,000 sheets of each transfer paper under the same conditions as the above-mentioned photoreceptor wear degree, normal copying? If there are no black lines or white spots in the copy image, mark it as ○.
The evaluation was rated as Δ if some black spots were observed, and × if black streaks or white spots were noticeable.

) Evaluation of ζl (As shown, with the transfer paper of the present invention, there was no abrasion of the photoreceptor and therefore the copy quality was good. Regarding the transfer papers of Comparative Examples 1 to 3, abrasion of the photoreceptor occurred, and therefore, the copy quality was also poor.

〔Effect of the invention〕

As described above, the present invention comprises pulp cellulose, a sizing agent,
The main component is a filler, and this filler is - (calcium carbonate/
In electrophotographic transfer paper that uses ram, the content of calcium carbonate in mb is less than 811 t%, so the photoreceptor,
There is almost no chance of carbonic acid adhering to cleaning blades, rubber rolls, etc.

Therefore, there is no contact between carbonic acid and the photoreceptor, which has the effect of preventing wear of the photoreceptor and the like.

Claims (1)

[Claims] An electrophotographic transfer paper containing pulp cellulose, a sizing agent, and a filler as main components and using calcium carbonate as the filler, characterized in that the amount of calcium carbonate is 8% by weight or less. Transfer paper.