JPS62184888A - Thermal stencil paper - Google Patents

Abstract

PURPOSE:To obtain a thermal stencil paper being inexpensive, giving favorable clearness of prints, being durable in printing and produced through easy lamination with a high molecular weight film, by laminating a tissue paper made from conjugated fibers having specified conditions with a high molecular weight resin film. CONSTITUTION:A tissue paper to be used comprises at least 30% of conjugated fibers formed from two kinds of thermoplastic high molecular weight materials having different melting points, the lower melting point component constituting at least a part of the surface of the fiber and the melting points being 90-140 deg.C. The tissue paper has a basis weight of 7-15g/m<2>, and is laminated with a high molecular weight resin film having a thickness of 2-10mum. A polyvinyl alcohol fibrous binder may be used in making the tissue paper, in an amount of not more than 10%. In such a case, the strength of the tissue paper is enhanced without deteriorating clearness of prints, so that the paper can be easily laminated with the resin film.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a heat-sensitive stencil paper made by laminating a polymeric fiber film to a thin paper mainly composed of composite fibers.

B. Prior art and its problems Heat-sensitive stencil paper (hereinafter referred to as stencil paper) is generally a porous thin sheet-like material laminated with a polymer resin film.

Such stencil paper has conventionally been made by laminating a polymer resin film to thin paper made of natural pulp-like materials such as bast fibers, and %1 published in No. 51-2513 and JP-A-59-28.
Although I find the one disclosed in Japanese Patent Application No. 96, both have some drawbacks. In other words, stencil paper using thin paper made of natural pulp-like materials such as tough fibers is made of thin paper made of flat materials such as honeycomb and Manila hemp, which blocks light during plate making and prevents ink from flowing during printing. Clear prints cannot be obtained because the passage is obstructed. Furthermore, the stencil paper disclosed in JP-A No. 51-2513 is made by pasting a polymeric resin film on a sheet material that does not deform at the heating temperature required for perforation, and the sea IF material is made of a natural pulp-like material or a compound fiber. Made of non-woven fabric. Among these, stencil paper using a nonwoven fabric made of a natural pulp-like material cannot produce clear prints as described above. In addition, non-woven fabrics made of compound fibers cannot produce thin, moderately strong thin paper suitable for stencil paper. It is difficult to bond the film together, and the resulting stencil paper has poor durability. Furthermore, the stencil paper disclosed in JP-A No. 59-2896 is made by laminating a polymer resin film to a thin paper made of polyester fibers with a circular cross section, but the thin paper is heat-pressed to ensure paper strength. However, as a result of such a press, the mesh formed by the polyester fibers can be narrowed down to a very small δ, which impedes the passage of printed matter ink and deteriorates the sharpness of the printed matter. In addition to going through the heat pressing process itself, it is necessary to uniformly heat press four sheets of polyester paper, which is weak in strength.
0 Means for Solving Problems The present inventors have developed a high-strength product that does not have these drawbacks, that is, is inexpensive, has good print clarity, has printing durability, and is easy to bond with polymeric films. As a result of intensive research to find a stencil paper made of thin kta, the present invention was developed.

First, the present invention is a composite f@fiber formed of two types of thermoplastic polymers with different melting points, a low melting point component occupies at least a part of the surface, and a sword/karu component having a melting point of 90 to 140°C. Composed of 30% or more and has a basis resistance of 7 to 15 f/r
A heat-sensitive stencil paper made by laminating a 2 to 10μ polymer resin film on rf light brown paper, which has succeeded in completely eliminating the drawbacks of conventional stencil paper. It is.

The stencil paper of the present invention is made by bonding a polymer resin film to R paper made of composite fibers, and the thin paper is made of compound #J
l! Although it is a textile paper, there is little binder, and there is almost no binder film at the fiber intersections, so there is little natural pulp-like material, and because there is no heat pressing, the mesh formed by the crucible is Appropriately large, resulting in print clarity. ■Composite fiber is the main component,
The low melting point components of such composite fibers are firmly owned, and other compounds N1. It also adheres to fibers and natural fibers, and is strong even though it is thin paper, so it has better adhesion to polymer resin films and is extremely durable. It has the advantage of being inexpensive because it uses almost no bast fibers.

The thin paper used in the present invention has a thickness of 30 or more conjugate fibers, and has a tsuboki of 7 to 15 f/m.
If the amount is less than %, the strength of the thin paper becomes weak, and wrinkles or damage may occur when laminated with a polymer resin film. If the tsubo'kjk force is less than 71/g, the strength of the rII paper will be diminished and the texture will be disturbed, and if it exceeds 15 f/r+1'', the printing clarity of the resulting stencil paper will deteriorate.Composite fibers It is advisable to mix polyhinyl alcohol (PVA and V) yarn fiber E binder within the range of 10% or less on light brown paper with a content of 30% or more. This is preferable because the strength of the thin paper is improved and the bonding of the polymer cross-layered film becomes easier.

# Paper made of composite fibers and PVA-based fibrous binder contains 50 or less fibrous materials with an official moisture content of 2.0 tenyl or less and 2.0% or more and 30 g natural pulp materials.
% or less, and the action of such fibrous materials or natural pulp materials improves the formation properties during paper making, which is very preferable.

The polymer resin film used in the present invention is made of a thermoplastic polymer and has a thickness of 2 to 10 microns. Examples of thermoplastic polymers include polyolefins, polyesters, polyamides, polyvinyl chloride, and vinyl chloride/vinylidene chloride copolymers. If the thickness is less than 2 μm, it is difficult to produce a film, and if it exceeds 10 μm, the clarity of printed matter will decrease. Accounts for at least a portion of the force 1&^01 - The melting point of the components used must be 90-140°C. The cross-sectional structure may be one-row type, core-sheath type, sea-island left, or windmill-like JIJ type with n (n is an integer of 2 or more). Examples of the low melting point component include polyethylene with a melting point of 90 to 140C, utilene/vinyl acetate copolymer, various yuzu polyester copolymers, and low melting point polyamide. Especially when the low melting point component is a copolymer of each phase ester,
The resulting thin paper is strong and non-KK is preferable. The high melting point component is preferably a thermoplastic polymer having a melting point 30°C or more higher than that of the low melting point component. The fM of the composite fiber is 0.5 to 6.
．． The fiber length is preferably 0 denier and preferably 1 to 15 cm. If the melting point of the low melting point component is less than 90°C, resin will accumulate on the surface of the dryer during paper making, making it difficult to peel off the thin paper, and if it exceeds 140°C, the adhesion of composite fibers will be poor with just the heat of the dryer. As a result, the strength of tissue paper becomes evident.

PVA-based fR fibrous binder is very effective in improving the strength of thin paper, with a degree of polymerization of 500-2500 and a degree of saponification of 85.
Made of PVA with mo1% or more or each extractive type PVA, and the temperature of the "underwater curing greenhouse" is 45-90℃, the fineness is (),
It is preferable that the fiber has a denier of 3 to 10.0 m and a fiber length of 1 to 10 m.

Fibrous materials or natural pulp materials having a denier of 2.0 or less and an official book fraction of 2.0 or more are very effective in improving the paper-making properties of light brown paper. PVA as a fibrous material with a denier of 2.0 or less and an official moisture content of 2.0 or more.

Examples include, but are not limited to, synthetic fibers such as acrylic, nylon, rayon, and acetate, and natural fibers such as cotton and silk. If the #& degree exceeds 2.0 denier, the formation formation in the wire gauze during paper making will be poor, and if the official moisture content is less than 2.0%, the transfer of the wet paper between felts during paper making will be poor.

Natural pulp-like products include various wood pulps such as kraft pulp and sulfide pulp obtained from coniferous or broad-leaved wood, Manila hemp, esparto leaf fiber pulp, flax, jute, kozo, mitsumata, and gampi. Bast fiber pulp etc. are destroyed.

The thin paper used in the present invention can be easily obtained by ordinary paper-making methods, and the stencil paper is made by coating either thin brown paper or polymeric resin film with a binder such as vinyl acetate, acrylic, or ester. It can be easily obtained by simply pasting the two together. As the drying conditions during paper making, a temperature condition between approximately the melting point of the low melting point component and approximately the melting point of the high melting point component of the composite fiber is used. In the present invention, normal paper-making conditions including drying conditions are used as paper-making conditions for thin paper, but these conditions prevent the conjugate fibers from becoming largely flattened or formed into a film.

D0 Effects of the Invention The stencil paper of the present invention is made by laminating a bird molecule resin film to a thin paper made of composite fibers, and has good printing clarity and has good lamination with a polymer resin film because the thin paper is strong. In addition, it is highly durable and uses almost no expensive bast fibers, making it affordable for women.

Unless otherwise specified, the percentage of non-inventiveness is expressed as a percentage of 0.The present invention will be explained below with reference to Examples.

Examples 1 to 4, Comparative Examples 1 to 4 The outer layer is polyethylene with a melting point of 110°C, and the inner layer is polyethylene with a melting point of 165
Core-sheath type made of polypropylene at ℃, 3 denier, 5
Kaku's composite fiber (hereinafter referred to as NBF3X5) is 80% and 0.
5 denier, 5 m polyester thread (hereinafter referred to as EPO53)
NBF3X575%IIE
P 053
105-2X3) 5% LD tissue paper with a basis weight of 12.2 mm/g (Example 2), NBF3X5 75%
, 0.5 denier, 3, PVA*fiber (or?&VPBO
52X3) 20%, VPB 105-2X35
%! ! ? unit:6E12.2f/rII Deroru 4
m paper (Example 3), outer layer made of ester copolymer with a melting point of 110°C, inner layer made of polyester with a melting point of 265°C #
4 denier 5tm composite fiber (hereinafter referred to as Merchii 4)
×5) 75%, VPB 052X3 20%, V
Made of PB 105-2X3 5%, basis release is 13.1
F/Godemer #i, a (Example 4), EP 053X
3 60% 1.3 denier, 5wR undrawn polyester fiber (hereinafter referred to as EP 131 %, EP 053X5
80%, VP B 105-2X35 thin paper with a chiyoshinari rating of 12.8f/rrf (Comparative Example 3), and NBF 3X5 75%, VPB052x3 20%
, VPB105-2x3 5% better weight is 30.2
? /d thin paper (Comparative Example 4) was produced by a conventional method. Note that the drying temperature during papermaking is approximately 120°C. Furthermore, the thin paper of Comparative Example 1 was pressed with a heated roll at 225°C (Comparative Example 2) c These thin papers were pasted onto a 3 μm polyester film coated with an ethylene-vinyl acetate adhesive and dried to produce a stencil paper. did.

The obtained stencil paper was made into a plate using a RISOGRAPH FX700, which is a heat-sensitive flash plate making machine. 2
Printed with 0CI printer.

Properties hL of the thin paper and stencil paper of the above Examples and Comparative Examples
are shown in Table 1. In Example 2 above, the composite fibers rj1 (Ji') constituting the stencil paper were not flattened or made into a film.

In Example 1, a polyester film is laminated onto a thin paper made of composite fibers and ester fibers, and since the thin paper is made of polyphonic composite fibers,
The force is strong, and the printing clarity of the stencil paper is destroyed. In Practical Example 2, the tissue paper of Example 1 was mixed with a small amount of PVA-based fibrous binder, and in Practical Example 3, the tissue paper was PVA instead of the Usueika ester fiber of Example 2.
Since it uses fJR fibers and is reinforced with a small amount of PVA-based fibrous binder, the strength of the thin paper is improved without impairing the printing clarity of the stencil paper. Example 4 Merchii 4 is a composite fiber in which Fi thin paper uses an ester copolymer with a melting point of 110"C in the outer layer.
Since it is made of 4 x 5, the adhesive properties of Melchie 4 x 5 are strong and strong, making it very easy to bond the polymer resin film together.

In Comparative Example 1, the thin paper was made of horizontally thin polyester, but it was not heat pressed, so its strength was extremely weak.

It is very difficult to attach a tetramolecular resin film, making it impossible to obtain a stencil paper suitable for mimeograph printing. Comparative Example 2 is Comparative Example 1
This stencil paper is made from heat-pressed thin paper, and is strong enough, but because the fibers are narrowed by the heat press, the printing clarity of the resulting stencil paper is insufficient. In Comparative Example 3, the thin paper was made of a small amount of composite fibers, so the strength was extremely low.

For this reason, as in Comparative Example 1, it is difficult to bond the straw-based film to the film, making it impossible to obtain a stencil paper suitable for mimeograph printing.

Comparative Example 4 uses thin paper with a larger basis weight than Comparative Example 2. Because the four-sheet paper is thick, the printing clarity of the stencil paper is poor.

From the above, it can be seen that the stencil paper of the present invention, in which a thin paper made of composite fibers is laminated with a molecular resin film, is very excellent.

Claims (1)

[Claims] 1. Formed by two types of thermoplastic polymers with different melting points, the low melting point component occupies at least a part of the fiber surface,
A heat-sensitive stencil paper made by laminating a polymer resin film of 2 to 10 μm to a thin paper having a basis weight of 7 to 15 g/m^2 and made of 30% or more of composite fibers having a melting point of 90 to 140°C. 2. The heat-sensitive stencil paper according to claim 1, wherein the thin paper comprises 30% or more of the composite fibers and 10% or less of the polyvinyl alcohol-based fibrous binder. 3. Thin paper consists of 30% or more of composite fibers, 10% or less of polyvinyl alcohol fibrous binder, 50% or less of fibrous material with 2 denier or less and official moisture content of 2.0% or more, or/and 30% of natural pulp material. A heat-sensitive stencil paper according to claim 1 consisting of the following: 4. The heat-sensitive stencil paper according to any one of claims 1 to 3, wherein the low-melting point component of the composite fiber is a polyester copolymer.