JPH01129258A - electrostatic recorder - Google Patents

Abstract

PURPOSE:To obtain a recording body not causing deformation due to expansion and contraction and applicable even to a plotter for electrostatic color CAD by sticking paper made from natural wood pulp to one side or both sides of a polyester film of a specified thickness, providing electrical conductivity and forming a recording layer on the resulting substrate. CONSTITUTION:Paper 3, 5 made from natural wood pulp is stuck to one side or both sides of a polyester film of <=8mum thickness, electrical conductivity is provided and a recording layer 1 is formed on the resulting substrate. When the thickness of the film is >8mum, the film is not preferable because ground stain is caused to an image. A stretched polyester film is optimum for use as the film 4 from the viewpoint of strength. The paper 3, 5 is required to be made from natural wood pulp because synthetic paper does not contribute toward improving the quality of an image. A recording body hardly causing expansion and contraction due to an environmental change is obtd., an image formed on the recording body has high density and ground stain is suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention is an electrostatic recording medium suitable for use in an electrostatic CAD plotter, and particularly suitable for use in an electrostatic color CAD plotter.

[Prior Art] Conventionally, electrostatic CAD plotters have been made using a base made of paper made from natural wood pulp that has been subjected to conductive processing, and one side of which is provided with a recording layer made of resin and pigment.

However, as electrostatic color CAD blocks have recently become widespread, expansion and contraction of the electrostatic recording medium during operation has become a problem.

In other words, in electrostatic color CAD, generally three or four colors of toner are developed sequentially.For example, if you want to create a red dot by overlaying yellow on a magenta dot, you need to record the magenta electrostatic signal. If the recording medium expands and contracts between the time it is plotted and developed and the next yellow electrostatic signal is plotted, and the two colors shift, two dots, magenta and yellow, will be recorded instead of red. Put it away. This becomes a big problem when drawing a high-density LSI pattern, for example.

The cause of this expansion and contraction is due to the electrostatic recording material.■
) Causes due to the influence of force such as tension during operation with a plotter, 2) Causes due to the influence of distortion during recording medium production, 3)
There are four possible causes: 4) due to the influence of temperature and humidity, and 4) due to the influence of the developer.

The biggest influence here is 3). Recording bodies used in electrostatic plotters are generally provided in the form of rolls, and the moisture content in the rolls is maintained at a specific value.

For example, if this is the equilibrium moisture content at 20° C. and 60% RH, if the atmosphere inside and outside the plotter during CAD operation differs from this, the moisture content of the recording medium will change, and the dimensions of the recording medium will change accordingly. This is particularly noticeable in the lateral direction of the recording medium. In addition, the influence of 2) is also large. In other words, distortion occurs in the recording medium during processes such as conductive processing and recording layer coating, and this distortion is fixed in the roll state, and then when it is placed in a different state, the distortion occurs in a relatively short period of time. As it attempts to open, dimensional changes occur in the vertical and horizontal directions.

Generally, causes 1), 2), 3), and 4) occur in combination. Up to now, several attempts have been made to address causes 2) and 3).

for example a2 Reduce beating of base paper raw materials.

b. Use special raw materials such as rugs.

Increase the amount of resin added to C1 paper.

(d) Making the manufacturing process as simple as possible; and (e) Performing sufficient seasoning. Each of these measures was effective, but the effects were small and other problems arose.

For example, using rag as a raw material was too expensive for its effectiveness.

When the beating was reduced, the strength of the recording medium was reduced. There was a limit to how simple the process could be, and the effects could not be said to be sufficient. Seasoning requires an extra process, increases costs, and has little effect.

Other attempts have been made in which the surface of a film made of polyester, polypropylene, vinyl chloride, etc. is subjected to conductive processing, and a recording layer is coated on top of the film. With this method, no expansion or contraction was observed, and in that respect it was highly effective.

However, almost no image could be obtained with a double-sided control type block in which the recording electrodes of the plotter are located on the front and back sides of the recording medium during recording. Also, the recording electrode is placed on the recording layer surface (front) of the recording medium.
Even with single-sided control type plotters located in the area, background smudges were large, and extra measures were needed to prevent this, such as insulating the developing section from ground.

[Objective] The present invention solves the above-mentioned problems of the prior art, does not cause expansion/contraction/deformation due to changes in the environment, and therefore provides an electrostatic color C.
The object of the present invention is to provide an electrostatic recording material that can also be used as an AD block.

[Structure] The structure of the present invention for achieving the above object has a thickness of 8 μm.
It is an electrostatic recording material in which a paper made from natural wood pulp is laminated on one or both sides of a polyester film having a size of less than m, and a recording layer is provided on a conductive-treated substrate.

The film used must have a thickness of not more than 8 μm. If the thickness is greater than 8 μm, background stains will occur on the image, which is undesirable.

In addition, a stretched polyester film is optimal in terms of strength. The paper attached to one or both sides of the polyester film must be made from natural wood bulbs.

When used as this paper, it becomes more transparent and can be used as a second original. The image was not good with synthetic paper. To laminate the film and paper together, any suitable method among known lamination techniques may be adopted.

Regarding conductive materials, quaternary ammonium salts, acrylates,
Sulfonate, conductive zinc oxide, conductive titanium oxide,
Tin oxide etc. can be used.

Whether the paper is laminated on both sides of the polyester film or only on one side depends on the required qualities such as curl, texture, and transparency. For example, curls will be smaller if both sides are pasted together, but this also depends on the type of conductive material used, etc., and cannot be determined unambiguously. The conductive treatment may be performed after lamination, or the lamination may be performed after conductive treatment.

To specifically explain the structure of the electrostatic recording medium of the present invention with reference to the drawings, in FIG. , a recording layer 1 is formed, and a back coat layer 6 is formed on the surface of the lower paper 5.

FIG. 2 shows another specific example of an electrostatic recording material in which a precoat layer and a recording layer are directly formed on the upper surface of a polyester film 4, a paper 5 is pasted on the lower surface, and a back coat layer 6 is provided on the surface of the paper 5. .

Hereinafter, the present invention will be specifically explained with reference to Examples.

Example 1 A commercially available biaxially stretched polyester film having a thickness of 3.5 μl was laminated with 35 g/m 2 high quality paper on both sides.

As the adhesive, a hot melt adhesive "Polyester" manufactured by Nippon Gosei Kagaku Kogyo ■ was used.

The amount used was approximately 5 g/m2.

A substrate was prepared by applying the quaternary ammonium salt polymer conductive material Chemistat 5500 manufactured by Sanyo Chemical Industries, Ltd. to both sides at a rate of 8.5 g/m 2 (dry solid content) on each side.

On one side of the recording layer, a recording layer containing calcium carbonate powder dispersed in acrylic resin was applied at 4.5 g/rA2 (dry solid content: 14 mm) to form an electrostatic recording medium.

Example 2 30 g/m on both sides of the polyester film of Example 1
' Copy paper pasted together. The adhesive used and others were the same as in Example 1.

Example 3 A commercially available biaxially stretched polyester film having a thickness of 8 μl was laminated with 55 g/m 2 of high-quality paper on one side (the adhesive was polyester). 1g of the conductive material of Example 1 on the paper surface
/m2, and 4.5 g/m2 was applied to the film surface.

The same recording layer as in Example 1 was provided on the paper surface.

Comparative Example 1 Biaxially stretched film with a thickness of 12 μm instead of the film of Example 1
A polyester film was used. An electrostatic recording medium was produced under the same conditions as in Example 1 except for the following conditions.

Hikeyaki Exchange Example 2 7g/m2 on each side of 55g/m2 high-quality paper made of the same material as the 35g/n2 high-quality paper used in Example 1.
' Chemistat 5500 was applied as a base. A recording layer under the same conditions as in Example 1 was provided on one side of this.

The above five types of samples were placed in an atmosphere of 20°C and 50% RH for 2 hours.
The mixture was heated for 4 hours to reach an equilibrium moisture state. 30℃, 75%
An electrostatic color plotter C23436 manufactured by Versatic Co., Ltd. was placed in an atmosphere of RH and 20° C. and 25% RH to produce a four-color image and an expansion/contraction test was performed. The results are shown in the table below. However, the expansion and contraction in the table is between the width direction (cross) of the paper flow, and the contraction is 11 strokes Wl.The density was measured using a Macbeth densitometer for the black monochrome area.

[Effects] As explained above, the electrostatic recording material of the present invention has little expansion and contraction when the environment changes, the formed image has a high density, and the background stain is small.

[Brief explanation of the drawing]

FIGS. 1 and 2 are explanatory diagrams specifically showing the structure of the electrostatic recording medium of the present invention. ■...Recording layer, 2...Precoat layer, 3...Paper,
4... Polyester film, 5... Paper, 6...
back coat layer.

Claims (1)

[Claims] An electrostatic recording material comprising a polyester film having a thickness of 8 μm or less, paper made from natural wood pulp laminated on one or both sides, and a recording layer provided on a conductive-treated substrate.