JPH01270058A - Electrostatic recording paper and its production - Google Patents

Abstract

PURPOSE:To obtain electrostatic paper which has >=60% transparency and does not generate whitening of folds by providing a dielectric layer to the surface, on the side where the smoothness is higher, of the base paper of conduction treated paper formed by coating or impregnating a conducting agent on or in both faces of single- face glossy Japanese paper having the base weight and smoothness of prescribed values. CONSTITUTION:The conduction treated paper is formed by coating or impregnating the conducting agent on or in both faces of the single-face glossy Japanese paper having 25-40g/m<2> base weight and >=100 second smoothness and the dielectric layer is provided on the surface, on the side where the smoothness is higher, of the base paper of the conduction treated paper to obtain the electrostatic recording paper which has >=60% transparency and does not generate the whitening of the folds. The electrostatic recording paper is otherwise formed by coating or impregnating the conducting agent liquid on or in both faces of the single-face glossy Japanese paper having 25-40g/m<2> base weight and >=100 second smoothness and drying the same, then processing the paper with a super calender further coating an electrostatic layer forming liquid to the surface on the side where the smoothness of the base paper is higher, then drying the coating.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to electrostatic recording paper, particularly electrostatic recording paper for electrostatic printer plotters in CAD, and a method for manufacturing the same. It can also be applied to paper.

[Conventional technology]

Recently, with regard to electrostatic recording paper, a drawing of a document is created and designed using a computer, etc., and then outputted using a high-speed electrostatic printer plotter. Output document 2 drawings are opaque plain electrostatic recording paper, transparent electrostatic recording paper based on natural tracing paper 9 transparent electrostatic recording paper impregnated with reactive resin, or plastic film. It is recorded on transparent electrostatic recording film based on . Among the electrostatic recording papers that have been used in the past, transparent type electrostatic recording paper is used.

Transparency is required because the film is used as an original for multiple copies in diazo. However, film cannot be folded and is expensive.

The transparent type is ideal for folding, circulating, and storing large drawings.
There are problems such as folding and blurring, which makes it difficult to see.

[Problem to be solved by the invention]

The present invention solves the above-mentioned problems of the prior art and has excellent transparency.
The purpose of the present invention is to provide transparent electrostatic recording paper that does not cause whitening on folds and can produce stable images over a wide range of humidity.

[Means to solve the problem]

The structure of the present invention to achieve the above object is to use single gloss Japanese paper with a basis weight of 25 to 40 g/m2 and a smoothness of 100 seconds or more on one side as the base paper, and a transparent paper coated or impregnated with a conductive agent on both sides. This is a transparent electrostatic recording paper that uses base paper as a support and further has a dielectric layer on the smoother side of the base paper.The Japanese paper used in the present invention is Japanese paper (6176) described in JISPOOI, especially machine-made paper. This paper is related to Japanese paper (6039) and is mainly made from bast fibers such as kozo, mitsumata, bark, Manila hemp, etc. It is also possible to mix wood pulp as a raw material depending on the purpose.Basic weight is 25
~40g/ffl.

One-sided gloss Japanese paper with a smoothness of 100 seconds or more on one side is optimal.

If the basis weight is less than 25 g/rd, the paper strength will be poor and paper breakage will occur during coating or impregnation with a conductive agent, resulting in a significant deterioration in workability. Also, the basis weight is 40g/rr? If you exceed
Transparency of 60% or more cannot be obtained and whitening of folds becomes worse.

When the smoothness is less than 100 seconds, the conductive layer becomes non-uniform,
A uniform image cannot be obtained.

The manufacturing process of the electrostatic recording paper invented this time involves first coating or impregnating both sides of a single-sided gloss Japanese paper with a basis weight of 25 to 40 g/m2 and a smoothness of 100 seconds or more on one side with a conductive agent. The optimum coating amount (impregnation amount) of the conductive agent is 3 to 7 g/i.

Since the conductive agent is generally a water-soluble polymer electrolyte, paper breaks tend to occur during the coating process when the conductive agent is applied or impregnated onto relatively low basis weight Japanese paper.

Also, dry wrinkles called "hijiwa" occur during the drying process. Therefore, by diluting the conductive agent with an organic solvent such as alcohol, ketone, or ester, in addition to water, paper breakage and wrinkles can be prevented.

As the conductive treatment agent used in the present invention, known polymer cation salts having a quaternary ammonium group such as polyvinylbenzyltrimethyl, ammonium chloride, polydimethylarylammonium chloride, and polyN-methylvinylpyridium chloride are used. Although particularly desirable, it is also possible to use other ionically conductive conductive agents having a tertiary amino group, a sulfonium group, or a phosphonium group. Further, it is also possible to use a polymer anion salt having a carboxyl group, a sulfone group, a sulfate group, a phosphate group, etc. in the molecule, although the effect of imparting conductivity is slightly inferior. It is also possible to mix or use a binder and other subcomponents with the conductive treatment agent.

After coating or impregnating with a conductive agent, the surface of the conductive layer is smoothed using a super calender. At this time, if the surface smoothness of the surface to which the dielectric layer is applied is less than 100 seconds, a sufficiently smooth surface cannot be obtained even with supercalender treatment, and a clear image cannot be obtained when recording. .

After supercalendering, a dielectric layer is applied to the smoother side of the base paper. It is a known product consisting of one or more of various copolymer resins such as styrene resin, silicone resin, epoxy resin, etc., or the binder is a resin such as styrene resin, silicone resin, epoxy resin, etc., and the same weight part or less of an inorganic pigment or an organic pigment is used. It contains. Examples of inorganic pigments include extender pigments such as kaolin, calcium carbonate, barium sulfate, and amorphous silicic acid, and examples of organic pigments include synthetic resin powders such as polyethylene powder and polystyrene powder, starch powder, and cellulose powder. By mixing these pigments, it is possible to give writing properties and the feel of plain paper. The coating amount of the dielectric layer is preferably 3 to 10 g/nf.

〔Example〕 The present invention will be specifically described below based on Examples.

Note that the amounts (parts) of each component described in the Examples are parts by weight.

Example 1 A liquid having the composition of a conductive agent liquid was applied with a wire bar to the smoother side of Japanese paper with a basis weight of 29 g/rrr and a smoothness of 120 seconds so that the dry adhesion amount was 3 glrd. , and dry at 80°C for 1 minute.

On the other side of the paper, a liquid having the composition of a conductive agent liquid was applied with a wire bar to a dry adhesion amount of 2g1rd, dried at 80°C for 1 minute, and the conductive paper was placed in a super calender.

Furthermore, after dispersing the composition of the dielectric layer forming liquid for 30 minutes with an attritor, it was coated on the smoother side of the base paper with a wire bar so that the dry adhesion amount was 5 g/bo, and dried at 100°C for 1 minute. An electrostatic recording paper was obtained.

Example 2 A liquid with the composition of a conductive agent was applied to a single gloss Japanese paper with a basis weight of 35 g/nf and a smoothness of 120 seconds or more, with a dry adhesion amount of 5 g/rr! The conductive paper was impregnated with an impregnating machine so that the conductive paper was dried at 80° C. for 1 minute, and the conductive paper was placed in a super calender.

Furthermore, after dispersing the dielectric layer forming liquid with the following composition for 30 minutes using an attritor, it was applied to the smoother side of the base paper using a wire bar so that the dry adhesion amount was 5 g/rrf, and then dried at 100°C for 1 minute. An electrostatic recording paper was obtained.

Comparative Example 1 Electrostatic recording paper was prepared in exactly the same manner as in Example 1, except that glossy Japanese paper with a basis weight of 19 g/rd and a smoothness of 120 seconds was used.

Comparative Example 2 Electrostatic recording paper was prepared in exactly the same manner as in Example 1, except that glossy Japanese paper with a basis weight of 45 g/rrl and a smoothness of 120 seconds was used.

Comparative Example 3 Electrostatic recording paper was prepared in exactly the same manner as in Example 1, except that Japanese paper with a basis weight of 29 g/rrr and a smoothness of 15 seconds was used.

Comparative Example 4 Electrostatic recording paper was prepared in exactly the same manner as in Example 1, except that high-quality paper with a basis weight of 40 g/% and a smoothness of 30 seconds was used.

Tests were conducted on the above six types of samples, commercially available transparent electrostatic recording paper from Company A (using tracing paper), and transparent electrostatic recording paper from Company B (resin-impregnated type).

The results are shown in the table.

Margin below ☆ Visual judgment for folded confessions The measurement items were measured using the following equipment.

Transparency□Toyo Seiki Seisakusho TRANSMITTANCE
METER Diazo Copy Speed □ Ricoh SM 15
00 dial scale Crease appearance □ Visual evaluation Image density □ Matsushita BP-102, AO electrostatic plotter TYPE-C sharpness □ Visual evaluation 0: Good It was a Japanese paper-based electrostatic recording paper with excellent image density and good suitability for diazocopy.

〔Effect of the invention〕

As explained above, the effects of the electrostatic recording paper of the present invention are summarized as follows.

(1) High transparency and excellent suitability for diazocopy.

(2) The crease does not turn white.

(3) Images with high image density, clarity, and brightness can be obtained.

Procedural amendment June 22, 1986

Claims (1)

[Claims] 1. A conductive treated paper with a conductive agent coated or impregnated on both sides of single gloss Japanese paper with a basis weight of 25 to 40 g/m^2 and a smoothness of 100 seconds or more, on the side with higher smoothness of the base paper. 1. An electrostatic recording paper provided with a dielectric layer on its surface, having a transparency of 60% or more, and not causing a whitening phenomenon at creases. 2 Coating or impregnating conductive agent liquid on both sides of Japanese paper with a basis weight of 25 to 40 g/m^2 and a smoothness of 100 seconds or more, and after drying, apply it to a super calender, and then apply the conductive agent liquid to both sides of the paper, which has a higher smoothness. A method for producing electrostatic recording paper, which comprises applying a dielectric layer forming liquid to the surface of the paper and drying it.