JPH0532077A - Washi-style thermal transfer image receiving paper - Google Patents

Abstract

(57) [Summary] [Object] The present invention relates to a Washi-style thermal transfer image-receiving paper, which has excellent recording suitability such as high density of transferred ink, no thin line breaks, and no uneven printing on solid portions. Another object is to obtain a receiving paper having excellent paper-passing suitability. A Washi paper-like thermal transfer image-receiving paper containing 50% by weight or more of goosehide fibers and 10 to 50% by weight of straw pulp in a paper layer is obtained. Further, a Washi paper-like thermal transfer image-receiving paper is obtained in which the paper layers are multi-layered, at least one of the surface layers is a layer containing 50% by weight or more of goosehide fibers, and the inner layer is formed of fibers mainly composed of wood pulp. .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Washi-style thermal transfer image receiving paper.

[0002]

2. Description of the Related Art A thermal transfer system is one of the recording systems for characters and images in personal computers and word processors. This is because a heat-meltable ink consisting of a colorant and a binder (wax, etc.) is applied to a polyester film or the like, the narrowly slit ink ribbon is brought into contact with the receiving paper, and the ink is melted by the thermal head. It is transferred to a receiving paper for recording. This system is characterized in that plain paper can be used as the receiving paper, but in reality, there is a considerable difference in recording suitability depending on the paper. What is particularly important for the printability is that the density of the transferred ink is high, that there are no fine line breaks, and that there is no printing unevenness in the solid portion. For this reason, measures have been taken to make the paper as smooth as possible and to enhance the absorption of the melted ink on the paper surface. Further, in order to prevent the receiving paper from wrinkling or dulling when the printer feeds the paper, the receiving paper needs to have an appropriate rigidity.

In order to improve the absorption of the molten ink on the paper surface, JP-A-58-177395 proposes to treat the surface of the recording paper with waxes, and JP-A-60-19269.
No. 0 describes a proposal to provide a coating layer of acicular aragonite type light calcium carbonate on the surface of a recording paper using a synthetic polymer latex as a binder.

On the other hand, Japanese paper made mainly of fibers such as Sanpei, Japanese pomegranate, and goose bark has been used since ancient times because of its unique texture, toughness and little deterioration. When writing a letter in Japan, it is still practiced to use Japanese paper to write with a brush. In addition, Japanese paper is also used and recorded in official documents. With the recent development of electronic technology, word processors have become widespread in the world. Some of them can output a writing style font, which makes it easier to write a writing style letter. It is preferable that the paper used for this has a texture of Japanese paper, but if the conventional Japanese paper is used as it is, the density of the thermal transfer ink is low and fine line breakage is likely to occur due to low surface smoothness.
Therefore, machine-made papers, which are made from a paper material mixture mainly composed of Sannobu fibers and dried with a Yankee dryer to improve the smoothness of one side, have come to be used for this purpose, but the recording suitability is still insufficient. I could not say. In addition, the Yankee skin has excellent smoothness on only one side, and the back side has different recording suitability from the front side. Also, the rigidity was low and the suitability for paper passing was somewhat difficult. In order to solve these problems, if the surface is treated with wax or calcium carbonate is applied on the surface as described above, the recording suitability can be improved, but the texture peculiar to Japanese paper is lost. .

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to develop a Washi-style thermal transfer image receiving paper which solves these problems. More specifically, it is an object to develop a recording paper which has a texture of Japanese paper and is excellent in recording aptitude of the thermal transfer method.

[0006]

In order to solve the above-mentioned problems, the present inventor made a receiving paper using various papermaking fibers, and evaluated the recording suitability by using a thermal transfer printer.
As a result, they have found that the use of a specific fiber significantly improves the recording suitability and the paper passing suitability, and thus completed the present invention. That is to say, the gist of the present invention is that the paper layer contains 50% by weight or more of goosehide fiber and 10 to 5 of straw pulp.
Obtaining a Washi-style thermal transfer image-receiving paper containing 0% by weight, wherein the paper layer is composed of multiple layers, at least one of the surface layers is a layer containing 50% by weight or more of goosehide fibers, and the inner layer is mainly composed of wood pulp. To obtain a Washi-style thermal transfer image receiving paper formed of fibers.

[0007] The goose bark fiber used in the present invention means a purified goose bark fiber (a tissue in which fiber cells contained in the endothelium immediately below the outer coat) of the goose bark belonging to the family Ginkgoaceae are purified. As the goose skin, in addition to normal seeds, Miyama goose skin, striped goose skin, blue goose skin, oni goose skin, and Philippine goose skin commonly known as Sarago can be used. The fiber is refined by a conventionally known method. That is, after the peeled black skin is soaked in fresh water, the epidermis is removed, and it is boiled with wood ash, lime, caustic soda, soda ash, etc., exposed to river or snow, or bleached powder, sodium hypochlorite, chlorous acid. Purify by chemical exposure with soda. It is not clear why the use of geesekin fiber has excellent recording suitability due to thermal transfer.However, geesehide fiber contains more oil-and-fat substances than other fibers, which increases the affinity with heat-meltable inks. One of the reasons may be that the fiber diameter is smaller than that of the above-mentioned fibers, and it is flexible and the surface smoothness of the paper is large.

[0008] It has been found that the receiving paper made from only ganze fibers has insufficient paper-passing suitability, and the present inventor further studied. As a result, it was found that the use of straw pulp in a certain ratio with geesehide fibers can improve the recording suitability and paper-passing suitability.Also, by using a multi-layered paper layer and using a wood pulp layer with high rigidity as the inner layer, The inventors have found that the paper suitability can be improved and completed the present invention.

The straw pulp used in the present invention means a pulp produced from rice straw or straw as a raw material by a conventionally known method. The reason why the recording suitability by thermal transfer is excellent when used together with straw pulp is not clear, but straw pulp also contains a large amount of oil-and-fat substances, has a good affinity with heat-meltable ink, and works to improve surface smoothness. It was presumed that the reason was excellent. Further, by using this together, the rigidity is increased, and the paper-passing suitability of the printer can be improved. If the proportion of straw pulp added to the gang hide fiber is too large, the texture of Japanese paper is lost, and if it is too small, the rigidity becomes insufficient, and the paper-passing suitability is reduced. It is necessary to contain 10 to 50% by weight.

Next, an example of the method for producing the receiving paper of the present invention will be described. Goose bark fibers and straw pulp are used in naginata beaters, blender type beaters, etc., preferably with a freeness of 500.
~ 650 ml CSF beaten, and by appropriately adding papermaking auxiliary materials such as sizing agent, paper strength enhancer, colorant, filler, fixing agent, and papermaking sticky agent to the cylinder paper machine, short A conventionally known paper machine suitable for making long fibers, such as a net paper machine and a slanted wire paper machine, is used.
Paper is made at 200 g / m ² . At this time, as long as the texture of Japanese paper is not impaired, other papermaking fibers such as wood pulp,
A small amount of seed hair fibers such as cotton, bast fibers such as San-Tsubaki and Kozo, leaf fibers such as Manila hemp and sisal, synthetic fibers such as acrylic and vinylon, and semi-synthetic fibers such as rayon can be used in combination.

In the present invention, the paper layer may be formed as a single layer or as a multi-layered composite. Since goose bark fibers are expensive, if a paper layer consisting mainly of inexpensive wood pulp is formed on the inner layer and a paper layer mainly of goose bark fibers is formed on the surface, good printability and paper passability, and a paper-like There is an advantage that the present invention can be achieved inexpensively without impairing the texture. For the wood pulp, conventionally known ones such as NBKP, LBKP and NBSP can be used, and the freeness is usually 500 to 650 ml.
Beat it into CSF, add other papermaking fibers and auxiliary materials for papermaking to it as described above, and make paper using a combination machine of cylinder-long net and cylinder multi-tank paper machine. .

The surface layer is formed outside the inner layer, but it may be formed on one side or both sides. Since the inner layer is mainly composed of wood pulp, the rigidity can be improved. Therefore, the surface layer may be formed of ganpi fibers alone, or straw pulp may be used in combination. For the same reason as described above, the addition ratio is
Straw pulp is 10-5% for geese skin fiber 50% by weight or more
It is in the range of 0% by weight.

[0013]

【Example】

Example. 1 90 parts by weight of goosenose fiber (meaning dry parts by weight, the same applies hereinafter), 10 parts by weight of straw pulp (manufactured by Toho straw pulp), alkyl ketene dimer type sizing agent (trade name Hersize A
K-720, manufactured by Harima Kasei Kogyo) 0.2 part by weight, cationized starch (trade name: Neotac 130, manufactured by Nippon Shokuhin Kako) 1
With a prescription consisting of parts by weight, it was beaten to a freeness of 600 ml CSF, and paper was made with a cylinder paper machine at a basis weight of 70 g / m ² (dry weight, the same applies below). Drying was performed with a multi-cylinder cylinder dryer.

Example. 2 70 parts by weight of geese skin fiber, straw pulp (made by Toho straw pulp)
Same as Example 1 except 30 parts by weight.

Example. 3 50 parts by weight of gooseberry fiber, straw pulp (made by Toho straw pulp)
Same as Example 1 except 50 parts by weight.

Example. It is an example manufactured using a 4-cylinder 3-tank paper machine. Inner layer stock prescription NBKP 50 parts by weight LBKP 50 parts by weight Alkyl ketene dimer sizing agent (trade name Hersize AK-720, manufactured by Harima Kasei Co., Ltd.) 0.2 parts by weight Cationic starch (trade name Neotac 130, manufactured by Nippon Shokubai Co., Ltd.) ) 1 part by weight Freeness 550 ml CSF was beaten. Prescription of front surface layer and rear surface layer Same as in Example 2. And basis weight 20 g / m ² paper surface layer with the first tank, second to
The inner layer of 30 g / m ² was combined in a tank, and the back layer was 20 g / m ^{2 in a} third tank. Drying was performed with a multi-cylinder cylinder dryer.

Comparative Example. 1 Same as Example 1 except 100 parts by weight of goosenose fiber.

Comparative Example. 2 100 parts by weight of San Tsubaki fiber, the same as Example 1 except that a Yankee dryer was used for drying.

Comparative Example. 3 Fine paper with a basis weight of 66 g / m ² (pulp blend is NBKP: L
BKP = 1: 1) was coated with a coating layer having the following formulation by a 4 g / m ² air knife coating machine and subjected to a super calendar treatment. Coating liquid blend Aragonite-based calcium carbonate (Product name: Tamapearl TP123, Okutama Industrial Co., Ltd.) 100 parts by weight SBR latex (Product name: SN-307, Sumitomo Nogatac manufacturing) 30 parts by weight

Table 1 shows the evaluation results of each example and comparative example. Evaluation is made by Toshiba Corporation word processor (Rupo
JW-R70F) was used to print solid and characters. The ink ribbon used was R1567 black from Toshiba Corporation. Evaluation items and methods Evaluation results by the 5-point method show that 5 is the best and 1 is the worst. Washi-style texture: judged by the feel of the hand and evaluated by the 5-point method. Surface smoothness: A center line surface roughness was measured using a stylus meter (Dektak manufactured by SLOAN) (unit: μm). Solid ink density: Macbeth densitometer (RD-1155
Type, using a visual filter). Print unevenness in solid area: visually determined and evaluated by a 5-point method. Fine line break: Visual evaluation and 5-point evaluation. Paper-passing suitability: The paper feeding mechanism of the printer visually observed the presence or absence of wrinkles and lumps, and evaluated by a 5-point method.

Table 1 shows the evaluation results of the examples and comparative examples.

[Table 1]

[0022]

As described above, the Washi-style thermal transfer image-receiving paper of the present invention is manufactured, and the recording suitability and paper-passing suitability can be improved as compared with the conventional Washi-style receiver paper, and the Yankee dryer is used. Even if the receiving paper is not dried, it is possible to manufacture a receiving paper having no difference in the front and back sides, and a receiving paper having a multi-layered structure can be manufactured at low cost, which is an excellent effect.

Claims (3)

[Claims] 1. A Washi-style thermal transfer image-receiving paper characterized in that the paper layer contains 50% by weight or more of geese hide fibers and 10 to 50% by weight of straw pulp. 2. A Japanese paper comprising a multi-layered paper layer, wherein at least one surface layer is a layer containing 50% by weight or more of geese hide fibers, and the inner layer is formed of fibers mainly composed of wood pulp. Wind thermal transfer image receiving paper. 3. The Washi-style thermal transfer image-receiving paper according to claim 2, wherein the surface layer contains 10 to 50% straw pulp.