JPH0699678A - Heat-sensitive autographic stencil paper - Google Patents

Abstract

PURPOSE:To provide heat-sensitive autographic stencil paper, which is excellent in secular stability at the preservation of base paper, improves the carrying properties of the base paper and image quality at plate making and prolongs the sevice life of a thermal head. CONSTITUTION:In the heat-sensitive autographic stencil paper prepared by laminating porous support and thermoplastic plastic film to each other, anti-heat- sealing layer, which contains thermoplastic resin, modified silicone having functional group and non-modified dimethyl silicone, is provided on the thermoplastic plastic film surface of the stencil paper.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-sensitive copying base paper.

[0002]

2. Description of the Related Art In recent years, in copy printing, the sensitivity of the base paper has been increased by the progress of the constituent materials (porous support, thermoplastic plastic film) and bonding technology.
With the progress and popularization of an integrated digital printer that makes a plate using a thermal head, the market has rapidly expanded as a simple and inexpensive printing system.

[0003] Since this heat-sensitive copy plate for stencil printing is plate-formed in a thermal head, the thermoplastic plastic film is heated and melted, and the thermoplastic plastic film is fused to the thermal head to destroy the thermoplastic plastic film (sticking). In addition, since the head debris adheres to the thermal head, it adversely affects the transportability of the base paper, the image quality, and the life of the thermal head.

On the other hand, conventionally, a method of forming, for example, a silicone oil or a silicone resin layer, or a polymer thereof as a heat fusion preventing layer on a thermoplastic plastic film (Japanese Patent Laid-Open No. SHO11-96). 64-56593, JP-A-3-189195
Etc.) have been used.

However, in these methods, when the base paper is rolled and stored for a long period of time (about half a year to about one year), the releasing component in the heat fusion preventing layer on the thermoplastic plastic film is porous. Since it is transferred to the side of the high-quality support (which is considered to be the movement of the molecule having a siloxane bond), its performance deteriorates over time, and as a result, the roll-like blocking of the base paper begins and the releasability decreases. Various problems as described above have occurred.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and provide a heat-sensitive copying base paper whose performance is excellent in stability over time.

[0007]

DISCLOSURE OF THE INVENTION The present invention relates to a thermosensitive copying base paper obtained by laminating a porous support and a thermoplastic plastic film, and a modified silicone having a thermoplastic resin and a functional group on the thermoplastic plastic film. A heat-sensitive copying base paper provided with a heat-fusion-preventing layer containing a resin and an unmodified dimethylsilicone.

The present invention will be further described with reference to preferred embodiments. The porous support used in the heat-sensitive copying base paper of the present invention needs to be porous so that the printing ink used at the time of printing can pass through, for example, various papers, especially coarse-grained paper such as Japanese paper. And synthetic paper or mesh sheet made of chemical fiber such as rayon, vinylon, polyester, acrylonitrile, polyamide, and mixed paper of chemical fiber and natural fiber such as Manila hemp, Kozo, Mitsumata, etc. Any of those used as the can be used in the present invention is not particularly limited, for example, natural fiber paper or mixed paper mainly composed of cellulosic fibers having a basis weight of 8 ~ 12 g / m ² and the like. Used to advantage.

The thermoplastic plastic film to be laminated on the surface of the above-mentioned porous support is also one which has been used in the heat-sensitive copying base paper of the prior art, for example, polyvinyl chloride film, vinyl chloride-vinylidene chloride copolymer film,
Polyester film, polyethylene, polyolefin film such as polypropylene, polystyrene film or the like can be used, and these thermoplastic plastic films can be easily perforated by heating means such as a thermal head. Thickness is 20
μm or less, preferably 10 μm or less, optimally 1 to 5 μm
The thickness is m.

The above heat-sensitive copying base paper has excellent plate-making characteristics, but when a thermal head or other method is used to heat the thermoplastic plastic film to form the copying hole, the thermal head may be changed depending on the conditions. May adhere to the thermoplastic plastic film to destroy the thermoplastic plastic film, or if the positive original film is used to form a copy hole by exposure, the positive original film may be stuck.

In order to solve such a problem, the heat-sensitive copying base paper of the present invention is characterized in that a heat-sealing preventing layer is provided on the surface of the thermoplastic plastic film. This heat fusion preventing layer needs to be heat fusible and non-sticky. Examples of such heat-meltable thermoplastic resin include polytetrafluoroethylene, polychlorotrifluoroethylene, tetrafluoroethylene-hexafluoroethylene copolymer, fluororesin such as polyvinylidene fluoride, silicone resin, and polyvinyl resin. An acetal resin, a polyvinyl butyral resin, a polyoxyethylene terephthalate, a polyethylene terephthalate, a polyethylene oxide resin or the like can be used, and a polyester resin is particularly preferably used.

Further, for the purpose of improving the slipperiness and the like of the thermoplastic resin layer, examples of the modified silicone having a functional group include alcohol-modified silicone, epoxy-modified silicone, polyester-modified silicone, fluorine-modified silicone and vinyl-modified silicone. Silicone, particularly preferably, a modified silicone such as amino-modified silicone oil is added, and in addition to this, trimethyl silicone as a non-modified silicone, methylphenyl silicone, and particularly preferably unmodified dimethyl silicone oil is used. Add. As for the compounding, both are added at a ratio of about 10 to 200 parts by weight per 100 parts by weight of the above resin to form a fusion preventing layer. In the above composition, if the viscosity of the unmodified dimethyl silicone is less than 100,000 CS, the effect of anti-sticking decreases, so the viscosity of the unmodified dimethyl silicone is preferably 100,000 CS or more.

The heat-sealing preventive layer made of these resins is prepared by dissolving or dispersing these materials in an organic solvent or water to prepare a coating solution, which is applied to the surface of the thermoplastic plastic film by an arbitrary method. Should be formed. If the thickness of the heat fusion preventing layer is too thick, the heat sensitivity is lowered and the formation of perforations becomes insufficient. Therefore, the thickness is preferably thin, and for example, a thickness of about 0.01 to 1 μm is preferable. The time of forming the heat-fusion-preventing layer is not particularly limited, and may be after or during the formation of the thermosensitive copying base paper in which the thermoplastic plastic film and the porous support are adhered, or the thermoplastic plastic film. It may be formed on the original fabric.

That is, in a preferred embodiment, the thermoplastic resin forming the heat-sealing preventive layer is a polyester resin, the modified silicone having a functional group is an amino-modified silicone, and the viscosity is 100,000 CS. It is a heat-sensitive copying base paper containing the above-mentioned non-modified dimethyl silicone. Further, the heat-fusible anti-fusing layer is a heat-sensitive copying base paper containing a copolymer of a polyester resin and an amino-modified silicone and an unmodified dimethyl silicone having a viscosity of 100,000 CS or more.

[0015]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples. (Example 1) Polyester resin as a raw material for the heat-sealing preventive layer Byron 103 manufactured by Toyobo Co., Ltd. 72% by weight Amino-modified silicone manufactured by Shin-Etsu Chemical Co., Ltd. X-22-161B 18% by weight Dimethylsilicone Shin-Etsu Chemical Co., Ltd. KF-96 [400,000 CS] 10% by weight was diluted with a solvent of toluene and methyl ethyl ketone in a weight ratio of 1: 1 to prepare a biaxially stretched polyester film 1.8 μm.
0.15 g / m ² was coated on the film surface of the base paper on which the porous paper and the polyester support were laminated. After that, store at 40 ℃ 90% RH for 2 months, then plate making speed 33 m
When the plate was continuously made for 4 minutes with an energy of sec / line and 0.127 mj / dot, it had excellent releasability without causing any head residue or sticking, just as immediately after coating.

(Example 2) In Example 1, the dimethyl silicone was changed to KF-96 [400,000 CS] to obtain KF-96 [100,000 CS].
The same performance as in Example 1 was obtained.

(Example 3) As a raw material for the heat-sealing preventive layer, polyester resin Byron 200 manufactured by Toyobo Co., Ltd. 1 part by weight Amino-modified silicone Shin-Etsu Chemical Co., Ltd. X-22-16113 2 parts by weight Tolylene diene A block copolymer was synthesized using 2 parts by weight of isocyanate (TDI), and purified by reprecipitation. Then, this block copolymer was mixed with dimethyl silicone (manufactured by Shin-Etsu Chemical Co., Ltd.) KF-96 [400,000 CS] at a weight ratio of 9: 1. When this mixture was diluted with a solvent of toluene and methyl ethyl ketone in a weight ratio of 1: 1 and subjected to the same coating / preservation test as in Example 1, the same evaluation as in Example 1 was obtained.

Comparative Example 1 In Example 1, when dimethyl silicone KF-96 was not added, good results were obtained immediately after coating, but at 40 ° C. and 90% RH. Sticking occurred after storage in the environment for two months.

(Comparative Example 2) In Example 3, when dimethyl silicone KF-96 was not added, head dust was generated immediately after coating.

The following Table 1 shows the sticking, thermal heads, and sticking of the above Examples and Comparative Examples immediately after coating (T0), after storage at 40 ° C. and 90% RH for 2 months (T2).
The results of blotting are shown. The evaluation symbols in the table represent ◯ good, △ acceptable, and × not acceptable.

[0021]

[Table 1]

[0022]

According to the present invention, the storability of the base paper is increased by improving the temporal stability of the heat-sealing preventive layer,
Not only can the cost be reduced, but the life of the printer, especially the thermal head, can be extended.

Claims (5)

[Claims] 1. A heat-sensitive copying base paper obtained by laminating a porous support and a thermoplastic plastic film, wherein a thermoplastic resin and a modified silicone having a functional group and an unmodified dimethyl silicone are provided on the surface of the thermoplastic plastic film. A heat-sensitive copying base paper provided with a heat-fusion preventing layer containing 2. The heat-sensitive copying base paper according to claim 1, wherein the thermoplastic resin constituting the heat-sealing preventing layer is a polyester resin. 3. A modified silicone having a functional group which constitutes the heat-sealing preventive layer is an amino-modified silicone.
The heat-sensitive copy base paper described. 4. The heat-sensitive copying base paper according to claim 1, wherein the viscosity of the unmodified dimethyl silicone constituting the heat-sealing prevention layer is 100,000 CS or more. 5. A heat-sensitive copying base paper in which the heat-sealing-preventing layer contains a copolymer of polyester resin and amino-modified silicone and unmodified dimethyl silicone having a viscosity of 100,000 CS or more.