JPH0422674A - Paper for impact printer - Google Patents

Abstract

PURPOSE:To perform impact recording excellent in transparency by providing an alumina hydrate layer on a base material. CONSTITUTION:A layer composed of alumina hydrate is provided on a base material. Therefore, ink absorbability necessary for impact printing is imparted and, in addition thereto, writing and coloration become possible regardless of aqueous ink and oily ink. As alumina hydrate, pseudobohemite is pref. from such an aspect that the good absorbability and adsorbability of ink are obtained. The alumina hydrate layer has a pore structure substantially composed of pores having a radius of 10-100Angstrom and pref. bas a pore volume of 0.3-1.00cc/g because sufficient absorbability is imparted and the transparent ink receiving layer is obtained. When the base material is transparent, a transparent material is also obtained. When the base material is opaque, physical properties necessary for impact printing can be imparted without damaging the qualitative feeling of the base material.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a recording material for an impact method.

(Prior Art) In recent years, with the progress of office automation, the demand for various printers as computer terminals has increased. The impact method is one of the methods that has been used for a long time, and recently the wire tod method has become mainstream, replacing the conventional type method. Compared to other methods, the impact method has high print quality (and can be used on copy paper used for various forms, etc.), so it is thought that it will not decline in the future.

On the other hand, overhead projectors are increasingly being used in place of slides at meetings and the like. In many cases, the OHP film used for this purpose was a copy of an original created using a word processor or the like onto a transparent film such as polyester using an electrostatic transfer copying machine, but from the standpoint of quality and time, it is possible to use an OHP film directly using a printer. It is hoped that the film will be obtained.

(Problem to be Solved by the Invention) However, in the impact method, the ink ribbon contains a solvent, and in the case of a transparent film such as an OHP film, it does not have absorbency. It is difficult to obtain sufficient ink absorption properties, and it is difficult to perform good printing with PET for printing and OHP films for PPC because the ink does not fix at all.

Furthermore, films developed for the impact method also have the disadvantage that transparency must be sacrificed to some extent in order to obtain good transfer performance, and the projected image becomes dark and lacks vividness.

In addition, conventional transparent films for impact methods do not have absorbency, so they cannot be blended or colored with water-based or oil-based pens.

(Means for Solving the Problems) The present invention provides a recording material for an impact system in which an alumina hydrate layer is provided on a base material.

In the present invention, a layer made of alumina hydrate is provided on the base material. Therefore, it has the ink absorbency necessary for the recording material in the impact method, and in addition, it is possible to write and color with either water-based ink or oil-based ink.

As alumina hydrate, pseudo-boehmite (AIO (O
H) ) is preferred. An alumina hydrate layer has sufficient absorbency when its pore structure consists essentially of pores with a radius of 10 to 100 people and a pore volume of 0.3 to 1.0 cc/g. It is preferable because the ink-receiving layer has transparency. At this time, if the base material is transparent, a transparent recording material can also be obtained. When the base material is opaque, it is possible to provide the physical properties required for the impact method without impairing the texture of the base material.

In addition to these physical properties, the ink receiving layer preferably has an average pore diameter of 15 to 50 pores, and the average pore radius ±l.
It is particularly preferable from the viewpoint of achieving both fixability and transparency that the volume of the pores having a radius of O is 45% or more of the total pore volume. It is more preferable that the average pore diameter of the ink-receiving layer is 15 to 30 pores, and the volume of pores having a radius of ±10 pores of the average pore radius is 55% or more of the total pore volume. In addition, the measurement of pore size distribution in the present invention is carried out by
By nitrogen adsorption/desorption method.

In the present invention, various materials can be used as the base material. As the base material of the present invention, plastics such as polyethylene terephthalate, polyester, polycarbonate, fluororesin such as ETFE, etc. can be used. Further, for the purpose of improving the adhesive strength of the alumina hydrate layer, corona discharge treatment, undercoating, etc. can also be performed.

The thickness of the alumina hydrate layer is appropriately selected depending on the specifications of each printer, etc., but it is generally preferable to adopt a thickness of 0.5 to 20 μm. The thickness of the alumina hydrate layer is 0.5
If the thickness is less than μm, it is difficult to achieve the effect, and if it exceeds 20 μm, the transparency may be impaired or the strength of the alumina hydrate layer may be reduced, which is not preferable.

A method for forming an alumina hydrate layer on a substrate is to add a binder to alumina hydrate to form a slurry, apply it using a roll coater, air knife coater, blade coater, rod coater, bar coater, etc., and dry it. Can be adopted.

As the alumina hydrate, it is preferable to use sol-like boehmite because a smooth layer can be easily obtained.

As a binder, starch and its modified products, polyvinyl alcohol and its modified products, SBR latex, N
Organic materials such as BR latex, hydroxycellulose, and polyvinylpyrrolidone can be used. If the amount of binder used is too small, the strength of the alumina hydrate layer will be insufficient; on the other hand, if it is too large, absorption and fixing properties will be inhibited, which is not appropriate (5 to 50% of the alumina hydrate layer) It is preferable to adopt degrees.

The impact printer referred to in the present invention refers to a wire tod method in which an ink ribbon is struck onto a recording material using a cross section of a wire, a typewriter type in which a block of type is struck, etc., and is also called a page printer or a line printer. This method can also be found in

(Example) Example alumina sol (manufactured by Catalyst Kasei Co., Ltd., Cataloid AS-2) 5
1 part by weight (solid content) of polyvinyl alcohol was added to the parts by weight (solid content), and water was further added to prepare a coating liquid having a solid content of approximately 10%. This coating solution was applied onto a sheet-like base material made of corona discharge-treated polyethylene terephthalate (thickness 100 μm, Type O manufactured by Ongaku University) using a bar coater until the dry film thickness was 5 μm. Apply as shown,
It was dried to obtain a recording material.

The average pore radius of the obtained alumina hydrate layer was 20.
The total pore volume of 10 to 30 pore radii was determined. Furthermore, a printing test was conducted using a dot impact printer. The results are shown in Table 1.

Comparative Example 1 The base material itself used in Example 1 was subjected to haze measurement and printing test, and the results are shown in Table 1.

Comparative Example 2 A haze measurement and a printing test were conducted on a commercially available impact type OHP film, and the results are shown in Table 1.

Table 1 (Effects of the Invention) According to the present invention, a recording material suitable for the impact method can be obtained. When a transparent base material is used, impact recording with excellent transparency is possible.

Claims (1)

[Scope of Claims] 1. A recording material for an impact method in which an alumina hydrate layer is provided on a base material. 2. The recording material for an impact method according to claim 1, wherein the alumina hydrate is pseudoboehmite. 3. The recording material for an impact method according to claim 1 or 2, wherein the base material has substantially no absorbency. 4. The recording material for an impact method according to any one of claims 1 to 3, wherein the base material is transparent. 5. The recording material for an impact method according to any one of claims 1 to 4, wherein the alumina hydrate is obtained by coating and drying an alumina sol.