JPS61182989A - Thermal stencil paper suitable for making stencil by heating element - Google Patents

Abstract

PURPOSE:To obtain a thermal stencil paper ensuring favorable moving property of a thermal head, having excellent perforability and head abrasion resistance and free of contamination of the head, by providing a layer consisting of a composition containing at least one of a lubricant (exclusive of sodium salts and potassium salts), a surfactant and an oily substance, a binder and a specified powder, on a non-adhesive surface of a thermoplastic synthetic resin film. CONSTITUTION:A layer of a composition containing at least one of a lubricant (exclusive of sodium salts and potassium salts), a surfactant and an oily substance, a binder and a powder having a melting point of not lower than 250 deg.C and a particle diameter of not larger than 20mum is provided in an amount of 0.05-2.0g/m<2> on a non-adhesive surface of a film, is a laminate comprising a film having a thickness of not larger than 4mum and an ink-permeable support adhered to each other by an adhesive. By this, a thermal stencil paper can be formed which has excellent head running property, perforability and head abrasion resistance and generating little contamination of the head. A stretched film of vinylidene chloride, a vinyl chloride copolymer, a vinyl chloride resin having a high degree of crystallinity, a copolymer comprising propylene as a main component, a polyester resin or the like is used.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a heat-sensitive stencil paper suitable for producing a stencil blank using a thermal head.

(Prior art) A type of thermal stencil paper that uses a thermal element to obtain a stencil plate (
Hereinafter, it will be abbreviated as the thermal element type. ) is already well known, and recently there have also been proposals that attempt to directly create a stencil original without image formation using a word processor that integrates a thermal head and a printing machine (for example, JP-A-58-49519. JP-A-54-
88048, JP-A-54-133117. Japanese Patent Application Publication No. 1983-
143679) For example, the proposed thermal element type stencil paper binding is ■
Stretched thermoplastic synthetic resin film (hereinafter referred to as "film"); ■ Film with a thermal transfer layer; ■ Film and porous support bonded together; ■ Film with powder adhered to it. Or ■ A film and a porous support are bonded together and sodium laurate is applied to the film surface to prevent the thermal head from adhering. There is a heat-sensitive stencil paper (hereinafter abbreviated as infrared ray irradiation type ◇) whose purpose is to create a stencil plate by applying infrared rays from the side of the heat-sensitive stencil paper in close contact with the base paper and transmitting the heat generated in the image area to the stencil paper.

As a heat-sensitive stencil paper used for this purpose, there is one having a structure of porous support/adhesive/filter layer adhesion prevention layer.
In order to prevent the document from being fused to the film during plate making and the film from being torn when the original flI is removed, various anti-fusion layers have been devised.

For example, if the melting point of sodium stearate is 200% on the film,
Powder of 0.2w or less at temperatures above °C, alkylsulfonic acid,
Potassium of alkyl sulfates, ammonium salts, potassium of oleic acid amide sulfonic acids.

Providing sodium, ammonium salt, or room temperature curing silicone resin (Special Publication No. 48-10098, Special Publication No. 4
7-5139. Special Publication No. 48-1531, No. 1 Publication No. 58-1
53697 publications), the melting point is 40 to 40 when forming the film.
Single fatty acid at 150°C.

A film obtained by adding fatty acid ester or fatty acid amide to a resin is used (Japanese Patent Publication No. 48-1009), or the anti-fusing layer, support and/or adhesive are colored (fF Publication No. 54-83178.* Publication No. 59-2895)
There is something I did.

(Problems to be Solved by the Invention) In order to create a satisfactory stencil using a thermal element, especially a thermal head, 1) the stencil paper does not fuse to the thermal head during plate making and the stencil runs over the thermal head ( (hereinafter referred to as "head runnability") 11) Good perforation (hereinafter referred to as "perforability") +++) Ability to use the head for a long period of time to prevent shortening of the life of an expensive head (hereinafter referred to as "head wear resistance") J) etc. are required at least.

However, conventionally known thermal element type and infrared ray irradiation type heat-sensitive stencil papers have not been sufficient to meet these requirements.

In other words, when a thermal element such as a thermal head is brought into direct contact with the stretched film, the heat-sensitive stencil paper may be a film alone, a heat transfer layer provided on the back side of the film, or a combination of the film and a porous support. When pasted together, the film heat-fuses to the thermal head during plate making and the head travels? ＃There is a serious problem that a satisfactory stencil plate cannot be obtained because the film cannot be used as a base material.□On the other hand, the head running is slightly better than that of a film with powder particles fixed to the film surface, etc. This is still insufficient, and there have been problems such as the film breaking during plate making and head running performance being insufficient. In addition, a film in which a film and a porous thin leaf # are bonded together and sodium laurate is applied to the film surface has good head running performance, but has the problem of severe head wear.
Infrared irradiation type thermal stencil paper has various problems as a thermal element type thermal stencil paper, and cannot be used satisfactorily.

In other words, when sodium stearate, alkyl sulfonic acid, potassium salt of alkyl sulfate, potassium salt or sodium salt of oleic acid amide sulfonic acid, etc. are provided as an anti-fusing layer on the film, head wear is significantly accelerated. There is a drawback. In addition, ammonium salts of alkyl sulfonic acids and alkyl sulfates are normally oily,
Even if it is coated on a film, when it is handled in roll or sheet form, it migrates to the back side, so the stencil plate is created by infrared irradiation, so even though K can be used, it is a stencil plate for thermal heads that requires strict head running properties. As a base paper, it has the problem of unstable head running properties.Furthermore, the head running properties are still quite unsatisfactory even if powder or granules are simply fixed on the film to improve running properties. Single fatty acids, fatty acid esters,
Even if fatty acid amide is added to the resin to form a film, the head runability cannot be satisfied.Also, with conventional heat-sensitive stencil paper, even if the head runnability is possible, perforation is not satisfactory when plate making with a thermal head is performed.・For example, a film with a room-temperature-curing silicone resin may allow the head to run, but only a small amount of perforation occurs, resulting in poor print images.The reason for this is Although it is not clear, the perforation corresponding to one dot with the thermal head needs to be performed in an extremely short time of several milliseconds or less, and it is thought that this is because less thermal energy is applied to the film compared to the infrared irradiation method. Therefore, consideration must be given to the stencil paper to be perforated by a thermal head so that it can be perforated with lower energy than the conventional thermal stencil paper using infrared irradiation.

As mentioned above, the thermal element type thermal stencil paper that has been proposed so far satisfies all of the essential properties of the thermal stencil paper for this purpose, such as head running properties, perforation properties, and head abrasion resistance. -1 again. Infrared irradiation type heat-sensitive stencil paper also cannot satisfy the head running properties, perforation properties, head abrasion resistance, etc. required for thermal element plate making. Therefore, the present inventors set out to solve the above problems. After considering, first a stretched thermoplastic film of 4μ or less,
On the non-adhesive side of the laminate film bonded to the ink-permeable support with an adhesive, 0.05% of a surfactant and/or external lubricant other than sodium salts and potassium salts with a melting point of 80°C or higher is applied. More than one.

2.0tAr? Heat-sensitive stencil paper with layers consisting of:
He invented the patent application (1986-). However, although this invention solves the above three problems, there is still the problem that surfactants and external lubricants adhere to or around the head during plate making, staining the head (hereinafter referred to as "head stain").

Even if these substances stain the head, they do not have any adverse effect on head running performance, perforation performance, or head abrasion resistance and can be used for practical purposes; however, the operator should clean the head as appropriate. Alternatively, it is necessary to provide the head with a device that automatically cleans the head, resulting in problems such as complicated handling and an expensive plate-making machine.

(Means and effects for solving the problem) The present inventors have improved head running performance with a thermal head.

As a result of careful research into heat-sensitive stencil paper that has excellent perforation and head abrasion resistance, and is free from head stains, we have found that a thickness of 4.
In a laminate in which a film with a diameter of less than μ and an ink-permeable support are bonded together with an adhesive, one or more lubricants, surfactants, or oily substances other than sodium salts and potassium salts and a binder are placed on the non-adhesive surface of the film. 0,05 f/rr? Above, 2.0g/m
By providing 2 or less layers, head running performance, perforation performance,
He discovered that it was possible to create a heat-sensitive stencil paper with excellent head abrasion resistance and less head staining, and completed the present invention.

The film used here is a stretched film of vinylidene chloride/vinyl chloride copolymer, vinyl chloride resin with high crystallinity, propylene-based copolymer, polyester resin, etc. In order to obtain a printing original plate that can produce printed matter with a high degree of elucidation, the thickness of the film should be as thin as possible, and specifically, it is preferably 4 μm or less. The reason for this seems to be that the thermal energy given to the film by the thermal head is less than that of the infrared irradiation type. Due to the current availability of such ultra-thin films, polyester films are preferred. Although it is essential to use an ultra-thin film in the present invention, there are problems such as wrinkles or bending during handling, even when the film is alone or is provided with a conventionally known anti-fusing layer. Therefore, it is necessary to laminate ink-permeable supports to facilitate handling.

The ink-permeable support used here is not particularly limited, and natural or synthetic porous thin paper or mesh-like sheets known in the stencil paper industry can be suitably used. In addition, acrylic resin-based adhesives, vinyl acetate-based adhesives (
Polyester resin adhesives or nylon adhesives (including ethyne-vinyl acetate adhesives), polyester resin adhesives, or nylon adhesives are preferably used. ◇Also, the lubricant referred to in the present invention refers to lubricants used in so-called plastic processing. , anything other than potassium salt2 For example, paraffin wax, microcrystalline wax.

Liquid paraffin, mixtures of natural wax and synthetic wax, combined products of polyethylene wax and organopolysiloxane, paraffin and hydrocarbon resins such as dimethylpolysiloxane, stearic acid, hydroxystearic acid, fatty acids such as hydrogenated oil, stearamide, oxy Fatty acid amides such as stearamide, monoamides of oleyl higher fatty acids, bisamides of higher fatty acids, and complex amides of these.

Fatty acid esters such as n-butyl stearate, methyl hydroxystearate, polyhydric alcohol fatty acid ester, saturated 1]tt[ester, ester wax, complex ester, etc., fatty acid ketones such as ketone wax,
Fatty alcohols such as single higher alcohols and combinations thereof, glycerin fatty acid esters, hydroxystearic acid triglycerides, partial esters of fatty acids, partial esters of fatty acids and polyhydric alcohols such as sorbitan fatty acid esters, distearyl epoxy hexahydrophthalate, Phthalic anhydride derivatives, fine powder of tetrafluoroethylene resin, and even barium stearate.

Calcium stearate, Magnesium stearate,
Zinc stearate etc. are preferably used. Surfactants used in the present invention include anionic, nonionic, cationic and amphoteric surfactants excluding sodium salts and potassium salts. 1. For example, lauryl sulfate. Anionic surfactants such as ethanolamine, ammonium lauryl sulfate, jetanolamine alkyl phosphate, triethanolamine polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl phosphate, polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, Polyoxyethylene higher alcohol ether, polyoxyethylene octylphenyl ether, yt'lJ oxyethylene nonylphenyl ether, polyoxyethylene derivative, #4 OhrohiOlenxyethyleneoxykaicha! Block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan distearate, sorbitan tristearate, sorbitan monooleate, sorbitan trioleate, sorbitan sesquioleate.

Polyoxyethylene sorbitan monolaurate.

Polyoxyethylene sorbitan monohexalumitate.

Polyoxyethylene sorbitan monostearate.

Polyoxyethylene sorbitan tristearate.

Polyoxyethylene sorbitan monooleate.

Polyoxyethylene tetraoleate.

Glycerol monostearate, glycerol monooleate, polyethylene glycol monolaurate, polyethylene glycol monostearate, polyoxyethylene stearate, polyethylene glycol monostearate, polyethylene glycol distearate, polyethylene glycol monooleate, polyoxyethylene alkyl Nonionic surfactants such as amines, coconut amine acetate, stearyl amine acetate.

Cations and double-sided surfactants such as stearylamine oleate, lauryltrimethylammonium chloride, stearyltrimethylammonium chloride, cetyltrimethylammonium chloride, distearyldimethylaraurylcarboxymethylhydroxyethylimidazolinium petaine, etc. can be suitably used. Further, as the oily substance that can be used in the present invention, for example, various mineral oils, vegetable oils, silicone oils, fluorine oils, etc. can be suitably used.

The binder used in the present invention is used for the purpose of binding powder to the film used, and its type is not particularly restricted as long as the purpose is achieved, and the type of binder used depends on the type of film used. The binder to be used can be selected according to the following criteria: 1. For example, polyester, polyurethane, polyamide, polycyclized vinyl, polyvinylidene chloride, polyvinyl acetate, acrylic resin, polyvinyl butyral, polyacrylonitrile, polycarbonate, cellulose resin, etc. In addition to thermoplastic resins, the present invention may also use curable resins such as curable silicone resins and curable urethane resins.

Father, as for the powder used in the great invention, powder that softens at less than 250°C will not be able to satisfy head running properties, which is one of the objectives of the invention, and powder with a particle size exceeding zOμ will not be used. Since satisfactory perforation, which is one of the objects of the present invention, cannot be achieved, it is necessary to use powder with a melting point of 250° C. or higher and a particle size of 20 μm or less. Such a powder may be any powder that satisfies the above conditions; for example, clay, calcium carbonate, titanium oxide, satin white, zinc oxide, barium sulfate, aluminum silicate, silica powder, etc. can be suitably used. The great invention is to apply one or more lubricants, surfactants or oily substances excluding sodium salts and potassium salts on the film surface of a laminate of a film and an ink-permeable support, and a binder with a melting point of 250°C or higher. This objective can only be achieved by providing a composition containing at least three types of substances that are powders with a diameter of 20 μm or less; for example, if powders are excluded from these substances, the objective cannot be achieved at all. The reason for this is not clear, but when observing the coated surface with an electron microscope, it seems that it is formed due to surface tension during the drying process, but lubricants, surfactants, oily substances, binders, etc. gather around the powder, forming a film. These substances are scattered on the surface with powder as the core, and microscopically these substances are not uniformly present. Therefore, for example, even if a curable resin is used as a binder, the curable resin film is not uniformly formed on the film surface, and it is considered that this does not inhibit the melting and shrinkage perforation of the film. Furthermore, during the drying process, the powder becomes a nucleus due to surface tension, and binders, lubricants, surfactants,
Oily substances etc. gather together, but the binder becomes relatively difficult to move due to the volatilization of the solvent, and is mainly a lubricant that exists in high concentration between the film and the powder and has poor compatibility with the binder.

It is thought that the surfactant or oily substance is poured onto the top of the powder. As a result, microscopically, the contact area between these substances and the thermal element becomes smaller.

In addition, since the heating element comes into contact with the surface of the powder containing a large amount of lubricant, surfactant, and oily substances, it is thought that head running performance is good and head wear is reduced. Furthermore, even if lubricants and surfactants exist in a molten state between the heating element and the powder during heating, the powder has a considerable oil absorption property, so when grooving is performed again, the surfactant and oily substances are removed from the powder. This seems to be absorbed and reduces the amount of dirt on the head.

Further, in the present invention, the amount of these compositions provided on the film is preferably 0.05 g/m2 or more and 2.0 g/m2 or less.

0,059/rr? Below this, the head running performance is insufficient.

Moreover, if it exceeds 2.0 C, as mentioned above, it becomes difficult to make these compositions exist in dots, making it difficult to achieve the object of the present invention.

Furthermore, the blending ratio of one or more of the lubricants, surfactants, or oily substances used in the present invention, the binder, and the powder varies depending on the characteristics of the materials used, so it cannot be determined unconditionally, but the amount of the binder used depends on the amount of the binder used in the film. The minimum amount necessary to achieve the purpose of binding is 1.
Usually 5 to 40% by weight of the total composition, although it varies greatly depending on the particle size and specific gravity of mineral powder, usually 10 to 80% by weight, and 10 to 80% by weight of lubricants, surfactants, oily substances, etc. A range of is preferred.

Note that in the present invention, in addition to one or more essential components,
It is also possible to appropriately add other known additives 2, such as colorants, mold release agents, plasticizers 1 and dispersants. is not limited to this example ◇ Example 1 Acrylic emulsion adhesive [
Konishi Co., Ltd.Ill! rAP-39J), dried fl
It was coated with a roll coater to give a k0.6 sheet, and immediately laminated with 12 sheets of porous tissue paper ("Stencil Paper" manufactured by Nihon Shigyo Co., Ltd.) to form a film/adhesive/ink-permeable support. On the 0-nuclide layered film prepared with the polymer, the following composition was dispersed with an attritor for 1 hour, and after drying, the coating solution was applied with a wire bar to a thickness of about 0.8 seams to prepare the heat-sensitive stencil paper of the present invention. did.

Composition The base paper thus obtained was printed with a thermal head (manufactured by Matsushita Electric Central Research Institute, long-distance printing device, equipped with a 6-dot/Koh thermal head). Head running performance is very good.

Further, almost no dirt was observed on the thermal head after printing.

Further, as a result of printing the thus printed material using a stencil printing machine [Roneo 970J manufactured by Gakken Co., Ltd.], a printed matter corresponding to the dots of the thermal head was obtained.

In addition, this base paper was printed with a checkered pattern for 2000 m using a thermal head.
Continuous printing was performed, and the dust wear on the thermal head before and after printing was investigated by measuring the surface roughness of the thermal head with a "Surfcom 300B model" manufactured by Tokyo Seimitsu Co., Ltd. The result was less than 1μ〇Example 2 Implementation The following composition was coated on the film of the laminate prepared in Example 1 while changing the coating t, and as in Example 1, the head running property was
Head dirt, print quality and coating 0.5f/r? Head wear was examined in the same manner as in Example 1.

Composition 1: After dispersing everything except the modified vinyl acetate resin with an attritor, the modified vinyl acetate resin was added to the dispersion and stirred to prepare a solution. Composition 2: After dissolving the polyester resin in toluene, dimethylsiloxane was prepared. Oil and finely powdered calcium carbonate were added and dispersed in a ball mill for 15 hours to prepare a coating liquid.

Composition 3 These were mixed and dispersed with a sand grinder to prepare a coating liquid.Composition 4 These were mixed and dispersed with a sand grinder to prepare a coating liquid.The results are shown in the table below. ] Note) Head running performance Head dirt Printing image quality Example 8 The following coating liquid was applied on the film of the laminate prepared in Example 1 after drying to a temperature of 0.5VW? Apply and dry so that

A mixed product of natural wax and synthetic wax was added to 22 parts by weight of O coating liquid water in the same manner as in Example 1.
Manufactured by Japan Interstub Co., Ltd. [Interstub G3259J
) 2 parts by weight of silica powder (Fuji Davison Chemical Co., Ltd. "Syroid 411 parts by weight" and a nonionic surfactant as a dispersant [Nippon Nyukazai Co., Ltd. "Nukol 210")
J] After adding 0.12 parts by weight and dispersing with an attritor,
Polyvinyl acetate emulsion (Daicel Chemical Industries, Ltd.)
2 parts by weight of Sehi 77A-522j manufactured by Sehi 77A-522j (solid content 47%) were added and stirred to prepare a coating liquid.

Eight types of silica powder with different particle size distributions were used to create eight types of coating liquids.The head running properties, head stains, and print image quality were as follows.

Example 4 A laminate was created in the same manner as in Example 1, except that instead of the 2.5μ polyester film in Example 1, 8μ, 4μ, and 6μ biaxially stretched polyvarnish biaxially stretched films were used.
The coating liquid used in Example 1 was coated onto the film so that the thickness was 1.0 after drying, and printing was carried out in the same manner as in Example 1. Head running performance and head staining were both good.

As a result of printing the prints thus made in the same manner as in Example 1, the prints using 8μ and 4μ polyester films were faithfully printed according to the dots, but the latter had slightly lower density. The one using a 6μ polyester film did not have many perforations, so it was difficult to read the characters.

In the case of using a 7μ vinylidene chloride/vinyl chloride copolymer film, the printed image density was relatively high, but the reproducibility of dots was poor and the printed image quality was considerably inferior.

Comparative Example 1 Only the room temperature curable silicone resin used in Example 2 was applied onto the film of the laminate prepared in Example 1 to a thickness of 0.5 after drying, and a printing plate was made in the same manner as in Example 1. Head running was a little bad, but I was able to drive. However, when this was printed in the same manner as in Example 1, the ink came out only partially and the printed matter was unreadable. Comparative Example 2 In Example 2, 1 % of polyoxyethylene octylphenyl ether was added from Composition 1. Compositions were obtained by removing dimethylsiloxane oil from Composition 2, cold-curing silicone resin from Composition 8, and aluminum silicate from Example 4 (composition 1', respectively).

2', 3', 4') were coated onto the film of the polymer of Example 1 to a coating thickness of 0.5 after drying.

As a result of printing in the same manner as in Example 1, the head running of Compositions 1', 2', and 4' was extremely poor. Composition 8' had extremely bad head stains. Comparative Example 8 Aqueous sodium dodecylbenzenesulfone [Neopex F-25J, manufactured by Kao Soap Co., Ltd.] was applied on the film surface of the polymer prepared in Example 1. Potassium oleate soap [1-pR-14J manufactured by Kao Soap Co., Ltd.] was applied to a thickness of 0.5 seams, and a checkered pattern was continuously printed for 2000 m in the same manner as in Example 1, and the thermal head was worn before and after printing. As a result of the investigation, it was found that the head wear was 6μ and 5μ, respectively, and showed extremely large head wear compared to the stencil paper of the present invention. In addition, the head portion was seriously contaminated.

(Effects of the invention) Head running performance, head dirt, and perforation (print image quality) necessary for creating a stencil printing original plate using a thermal element, especially a thermal head.
A heat-sensitive stencil plate that satisfies both head abrasion resistance and head abrasion resistance has not been found to date.As can be seen from Examples 1 to 4 and Comparative Examples 1 to 8, a thermoplastic synthetic resin film with a thickness of 4μ or less A lubricant excluding sodium and potassium salts is placed on the non-adhesive surface of the thermoplastic polymer film and an ink-permeable support is bonded with an adhesive.
By providing a composition containing at least one kind of surfactant or oily substance, a binder, and a powder having a melting point of 250°C or higher and a particle size of 20μ or less, the thermal For the first time, we have been able to create a thermal stencil paper that satisfies the requirements for head running, head staining, perforation (print image quality), and head abrasion resistance required for element stencil printing plates.□

Claims (1)

[Claims] In a laminate in which a thermoplastic synthetic resin film with a thickness of 4μ or less and an ink-permeable support are bonded together with an adhesive, a lubricant excluding sodium salts and potassium salts, and a surfactant are placed on the non-adhesive surface of the thermoplastic synthetic resin film. one or more agents or oily substances, a binder, and a particle size of 20°C or higher with a melting point of 250°C or higher.
0.05g/m consisting of a composition containing powder of less than μ
A thermal stencil paper suitable for thermal element plate making characterized by having a layer of ^2 or more and 2.0 g/m^2 or less.