JPS63160894A - Original stencil paper for thermal stencil plate making - Google Patents

Abstract

PURPOSE:To enable high sensitivity and high resolution to be displayed, by laminating a stretched film of a thermoplastic resin specified in heat shrinkage stress value, heat shrinkage factor, tensile elastic modulus and film thickness with a base paper having regularly arranged projected parts so that the two can be released from each other at the time of printing after stencil plate making. CONSTITUTION:A stencil paper comprises a stretched film of a thermoplastic resin having a heat shrinkage stress of at least 75 g/mm<2>, a heat shrinkage factor of at least 30%, a tensile elastic modulus of at least 75 kg/mm<2> and a film thickness of 4-18 mum, and a base paper having regularly arranged projected parts wherein the effective area ratio of the projected parts to be brought into contact with the film at an effective part of plate making is 1-35%, the area per projected part is 2.5X10<-5>-1.44X10<-2> mm<2> and the height of the projected parts is at least 15 mu. Both ends of the film and the base film are laminated with each other so that they can be released from each other without damaging an image at the time of printing after stencil plate making. Thus, the stretched film having a specified performance, high sensitivity and high resolution is used, and the base paper having a specified range of shape in the region of large film thickness of the film is used with a low energy perforating means, so that stencil plate making through perforation with high sensitivity and high resolution can be achieved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention does not require a composite porous support to prevent images from being removed during printing, but the heat sensitivity of the film to be made during plate making (perforation) is not required. It relates to stencil printing base paper that is used by laminating a specific mount that can maintain high sensitivity and resolution in an easily peelable manner.

[Conventional technology and its problems]

Conventionally, when making heat-sensitive stencil paper, visible light and infrared rays are used as a heat source by the flashlight method, and the heat rays are absorbed by the manuscript in which characters, figures, and topography are displayed with a heat ray-absorbing material, and the heat is used to absorb the heat rays. A method is known in which a stencil sheet is prepared by melting a heat-conducting material on a film that is in contact with the display area and perforating it. In addition, a fibrous non-woven fabric, woven fabric or other type of porous support that initially passes through the printing ink is used to prevent the characters forming an image on the film from being removed during perforation or printing. It is also known that they are used by firmly pasting them together to prevent them from peeling.

There is also a known method for making plates by applying pulse signal power to the element at a predetermined location by contacting a heating element with the film surface of the base paper, and perforating the element with the heat.

In addition, the above-mentioned porous support is indispensable in normal methods in order to prevent the image from being cut out after perforating the film, and the above-mentioned base paper is still in practical use in large numbers and is the only base paper that is commercially available in large quantities. Although various other types of supports have been proposed, they have not yet been put to practical use and cannot be found on the market. The paper must be manufactured thin and uniformly and carefully laminated with a small amount of adhesive to avoid deterioration of sensitivity.On the other hand, its role as a support is to maintain sufficient operability such as stiffness of the base paper and to prevent perforation. In order to prevent the image area of the film from coming off during operation and printing, it was necessary to sufficiently adhere it with a specific adhesive in order to prevent it from being exposed to oils and the like contained in the ink during operation and printing. In order to satisfy these conflicting demands for equal pressure, the current situation is that the sensitivity and resolution of the base paper are being sacrificed to some extent. The supports currently used for the above reasons include extremely thin paper (Japanese paper) with a basis weight of about 15 to 7 g/m'', or woven fabric (gauze) made of synthetic fiber or the like and having a basis weight of about 50 to 300 a+esh. These materials are expensive, especially when using the latter type of gauze, which has better sensitivity and resolution than Japanese paper, but is particularly expensive.Therefore, its uses are also limited. The current situation is to put it away.

Furthermore, there is a variety of know-how regarding the laminating process and the adhesives used therein, and the current situation is that there are various complicated problems.

On the other hand, up until now, the main plate-making method has been to make holes by absorbing high-energy heat rays or light rays that can be converted into heat into an image of an original superimposed on a film surface. However, recently, methods have been considered to instantly and accurately drill holes using a small amount of energy that is applied to a thermal head with a small thermal element by applying a digitized signal, but the performance is insufficient and the thermal sensitivity is insufficient. Currently, there are various problems in terms of resolution, etc., and improvements are required.

JP-A-53-69710 discloses that the stretched film is made of vinylidene chloride-vinyl chloride copolymer, vinyl chloride polymer, polyethylene, polystyrene, polypropylene polyester, nylon, etc. with a thickness of 3.
Select a film of micrometer or less, then select kraft paper, art paper, synthetically processed paper, synthetic resin sheet, or thin aluminum plate as a carrier sheet that is permeable to ink, adhere the two to easily peel, and then Directly draw an image on the sheet, irradiate it with infrared rays, heat the ink portion of the image area, form the image in the form of a spider web with the molten resin, and peel off the latter carrier sheet and use it for printing. There is a disclosure of base paper that does not need to be pressurized with the original during plate making. Also, JP-A-1986-
Publication No. 180891 describes that as a film to be perforated by the heat of a thermal head, a film having a diameter of 10 μm or less, preferably 1 to 6
A film of μ is selected, and then, as a porous support, a paper-like material of 6 to 14 g/m'' made of synthetic fibers and natural fibers is laminated with an adhesive to an easily peelable material, and perforated with a thermal head. When peeling off a porous support, there is a disclosure of a base paper for the purpose of removing the molten resin by absorption into the support and preventing clogging of the image. - Publication No. 102296 discloses a method for improving image quality by printing a biaxially stretched film made of polyester or the like in such a way that the uniform layer thickness is eliminated and independent, approximately equal openings are formed at approximately equal density. There is disclosure regarding the base paper for the purpose of

Also, as publicly known information about the film itself, JP-A-48-82
No. 921 describes a film made of a vinylidene chloride copolymer, which is sufficiently heat-treated and plate-made by a flash method in which the areal heat shrinkage rate in practical use is controlled within the range of 0.5 to 3.0%. JP-A-51-2513 discloses a film made of polyethylene terephthalate that has been sufficiently heat-treated and has a density of 1.375 to 1.385 (g/cs), that is, 32 to 39% in terms of crystallinity. JP-A-60-85996 discloses a method using a film with a specific range of improved resolution corresponding to In both of the above two cases, a porous support is laminated and used as a preventive measure against image removal. , and belongs to cases where high-energy flash light (such as a xenon lamp) is used.
Satisfactory results were obtained by drilling with a thermal head using highly crystallized polyethylene terephthalate (commercially available, known to have mp, crystallinity of about 45% at 255-260°C, and density of 1.386 g/cm3). It is disclosed that the thickness of a film having a sufficient perforation sensitivity is about 2 μm or less. All of these relate to cases where the porous support is used for the same reasons as above.

[Problem that the invention seeks to solve]

In the above-mentioned known base paper, the perforation of the film itself that constitutes it is limited to high-energy flash light and lower-energy thermal heads (for example, those used in thermal transfer methods, etc., that is, 3 to 3 .5μm commercially available polyester film coated with wax-like ink) and thin film (e.g.
μm) and plate making (perforation) using base paper laminated with a support, especially in the latter case 2 μm
It is difficult to sufficiently perforate even a film as thin as 5 μm using a commercially available thermal head used in word processors, etc.; This is the current situation.

Therefore, there is a major problem in that the thermal head must be specially modified (which shortens its lifespan and goes against the trend toward lower energy consumption and higher speeds in the world), and there are inherent limits to how it can be used. The body is essential.

Although the present invention may be effective for the above-mentioned known perforation films, it is particularly preferably applied to films in the area that have better heat-sensitive perforation properties than the above-mentioned known films. This allows a synergistic effect that could not be considered at the above-mentioned known level. In other words, in order to use a high-sensitivity film and fully utilize its characteristics, that is, both high sensitivity and high resolution, in areas where the film thickness is thick, not only the above-mentioned film but also a specific mount is required. .

Conventional base paper laminated with the porous support for Bunbu has the above-mentioned cost problem, and the paper laminated with Japanese paper, which is currently in practical use, cannot be perforated with a thermal head. In the flash method, the melted film fragments fall off to the original side and are self-cleaned, but in the thermal head method, they have no choice but to adhere to the joints of the support, and are particularly harmful to Japanese paper. Filling the binding parts of grains or areas with high density of grains makes it difficult for ink to pass through the core parts during printing, resulting in lower resolution and sharpness (cutting of images), making it difficult to view the printed matter. <
There is a problem with this. This phenomenon is particularly aggravated when printing at high speeds, and if an attempt is made to prevent this by lowering the viscosity of the ink using another method, the resolution of normal areas will be reduced. This trend is reflected in film
When Japanese paper is used as a support, scum tends to form on the paper itself, and it is currently difficult to rationally perform high-quality printing. In addition, when gauze (mesh-like woven fabric) is used as the support, the above-mentioned drawbacks are greatly improved, but the problem of the scum remains, and the cost is extremely high, making it unsuitable for general use. , there are problems.

In addition, since the support is strongly adhered to the film to prevent the image from falling off, one reason is that the heat of the part corresponding to the minute image during perforation is absorbed by the support or adhesive, which greatly reduces sensitivity. In addition, with irregular Japanese paper-type supports, the perforated image becomes blurry and excessive energy is required, which causes areas where the perforations widen, resulting in a decrease in resolution. There is a point.

Next, a known porous support or simply an ink-impermeable paper or synthetic resin sheet is easily releasably laminated onto a conventionally known film, and the film is peeled off after perforation, as described above. In the case of the comparative example, it is insufficient for the same reason as mentioned above, and especially when making plates with a thermal head, it is necessary to use dense paper other than the above-mentioned porous support (ordinary paper with a higher density than the support). etc.), and resin sheets (including those with random irregularities such as sandblasting on the surface) are used as so-called mounts for the same purpose, the heat from drilling is taken away, and the heat from being pressed by the thermal head is removed. However, due to the heat being applied, the part of the film corresponding to the image moves freely, making it impossible to perforate the film sufficiently, which is completely unsatisfactory.The perforations are only irregularly perforated, and the film is not at a level worthy of practical use. Must not be. Furthermore, even if an independent pattern with openings is simply printed on the film, there are still problems with insulation as described above, it is difficult to effectively perforate the holes, and the pixels tend to be distorted and incomplete under high energy. . In addition, the printed image was incomplete due to adhesion of residue and missing images, and unnecessary lines remained on the printed image. It is also difficult to accurately pattern on thin film surfaces.

The inventors of the present invention have made various studies in consideration of the various problems described above, and have arrived at the following invention.

[Means and effects for solving the problems] The present invention has a heat shrinkage stress value of at least 75 (g/longji), a heat shrinkage rate of at least 30%, and a tensile modulus of at least 7.
5 (kg/mm2), and the effective area ratio of the stretched film made of thermoplastic resin with a film thickness of 4 to 18 μm and the convex portions that should be in direct or indirect contact with the film in the effective part of plate making is 1 to 1. 35%, and the area per one is 2.5 x 10-5 to 1.44 x 10 be (
It consists of a mount having a height of at least 15 μm and a regular arrangement of protrusions, and is laminated at both ends so that it can be peeled off without causing substantial damage to the image during printing after plate making. High-resolution, high-sensitivity
A heat-sensitive perforated base paper is provided.

The present invention will be explained in detail below.

The stretched film made of the thermoplastic resin of the present invention has a heat shrinkage stress value of at least 75 (g/mW"), preferably 100 to 1200 (g/mW"), more preferably 150 ~1000 (g/Tsuru2).This value was determined by sampling the film into a 10m-wide strip and placing it between chucks with strain gauges for 50m.
It was measured by setting it without loosening it as in Proverbs 1, immersing it in silicone oil heated to each temperature, and detecting the stress generated. The value was taken 10 seconds after immersion in silicone oil at 100°C or below, and the value 5 seconds after immersion in silicone oil at over 100°C. In the case of biaxial stretching, it is expressed as the average value in the vertical and horizontal directions, and in the case of uniaxial stretching, it is expressed as the stretching direction.

If even a part of the measured shrinkage stress curve for each temperature is included in the above value range, it is considered to be within the scope of the present invention. The above preferred values are when the measurement temperature is 60
-150 ('C), more preferably this range is 60-140 ('C), even more preferably 60-130 ('C), particularly preferably 60
~120('C). Also, the position of the peak value of the shrinkage stress with respect to temperature is preferably 70 to 150 ('C), more preferably 70 to 140 ('C), still more preferably 70 to 130 ('C), and particularly preferably 70 to 140 ('C). ~1
20 ("C). The lower limit of the heat shrinkage stress value is the basic property necessary for effective perforation, and below it, it becomes difficult to effectively perforate using the thermal head method. .

Moreover, when the preferable upper limit is exceeded, the apertures tend to widen and the film tends to be distorted, resulting in a decrease in the resolution of images and characters after printing. In addition, below the lower limit of the preferable temperature range in which the heat shrinkage stress is expressed, the dimensional stability of the film is likely to decrease, or the apertures may expand, or the film may be distorted, resulting in a decrease in the resolution of image characters ( Moreover, above the upper limit, the perforation sensitivity decreases and becomes particularly susceptible to the influence of the mount.
This makes it difficult to make accurate holes, which is not desirable.

Furthermore, when used without a porous support as in the present invention, the strength of the perforated portions tends to decrease.

In addition, this is one of the factors that makes it difficult to effectively perforate in regions where the film is thick. Further, if the position of the peak value of the shrinkage stress is below the above-mentioned lower limit, problems will arise in the dimensional stability and resolution of the film, and if it is above the upper limit, there will be a tendency for a decrease in sensitivity to occur.

Further, the heat shrinkage rate is at least 30 (%).

This value is preferably 35-90 (%), more preferably 40-80 (%). This value is 50m
A five-sided film sample was placed in a constant temperature bath set at a predetermined temperature and allowed to shrink freely for 10 minutes.The shrinkage of the film was determined and expressed as a percentage of the value divided by the original dimension, and the stress above was calculated. As in the case of biaxial stretching, it is expressed as the average value in the vertical and horizontal directions, and in the case of uniaxial stretching, it is expressed as the stretching direction.

The above-mentioned values are considered to be compatible if even a portion thereof is the above-mentioned value under any temperature conditions. Preferably, the above value is that the measurement temperature is within the range of 60 to 170 ("C>"), and more preferably, this range is 65 to 140 ("C").
'C), more preferably 65 to 120 (°C), particularly preferably 65 to 100 ('C).

If the above-mentioned heat shrinkage rate is below the lower limit, perforation will not occur effectively and the sensitivity will decrease.If it is above the preferable upper limit, the perforated hole will be likely to enlarge, images and characters will be distorted, and the resolution will be reduced. In addition, if the temperature range in which the above shrinkage rate occurs is below the lower limit, the dimensional stability of the film will decrease, the perforated holes will become enlarged, images and characters will be distorted, and the resolution will decrease. decline is more likely to occur.

Further, above the upper limit, the perforation sensitivity decreases, and it becomes difficult to perforate a thick film with a perforation means using a thermal head or the like.

The tensile modulus is at least 75 (kg/m2), and preferred values of this value are at least 10,100 (kg/m2), more preferably at least 125 (kg/m2), even more preferably 150 (kg/m2). ) That's it.

If the value is below this lower limit, the film tends to lack stiffness, making it difficult to handle and perforate smoothly. Additionally, enlargement of perforations and distortion of images are likely to occur, and after perforation, when peeled off from the backing paper or during printing, the film tends to stretch and deform images and characters (the measurement method is A S Measured according to TMD882-67, and the value at 2% elongation is converted to 100%.) The film thickness was 4 to 18 μm, preferably 5 to 15 μm, more preferably It is 6 to 13 μm, more preferably 6 to 12 μm. Below this lower limit, deformation and omission of images and characters on the film, wrinkles, and cracking of the film are likely to occur. Above this upper limit, not only the flash method but also the thermal head method are not effective perforation methods. However, this is not the case when using means such as a laser.

The thermoplastic resin constituting the film is not particularly limited as long as it exhibits the above-mentioned performance, but in order to form holes in a thick film region, it is preferably a copolyester-based resin, more preferably a low-temperature resin. Examples include crystalline/non-crystalline copolyesters, more preferably substantially non-crystalline copolyesters. For example, when copolymerizing an alcohol component, in addition to ethylene glycol, propylene glycol, 1
．． 4-butanediol, 1,5-bentanediol 1,
6-hexanediol, neopentyl glycol, polyethylene glycol, polytetramethylene glycol,
Cases in which at least one diol selected from cyclohexane dimetatool or other known ones, or the above-mentioned ethylene glycol are not included, but the above-mentioned one is used as a base, and at least one of the above-mentioned other components is also included. There is.

Next, when copolymerizing acid components, in addition to terephthalic acid,
Examples include isophthalic acid, phthalic acid, other aromatic acids, and dicarboxylic acids having substituents on the aromatic ring that do not contribute to the esterification reaction.

Further, it may contain at least one type of dicarboxylic acid selected from aliphatic dicarboxylic acids such as succinic acid, adipic acid, and others, or other known dicarboxylic acids. Either one of the alcohol component and the acid component may be used, or both may be used at an appropriate time. As an example of a preferable combination, for example, ethylene glycol is the main alcohol component and 1.4 cyclohexane dimetatool is used as the main component.
There are copolymerized products containing 0 mol% or less using terephthalic acid as the acid component.
It is about 40 mol%, more preferably about 25 to 36 mol%.

Next, in polyamide resin, so-called nylon-6,6
6,6-10,11,12, copolymerized nylon-6-66
, 6-66-610, 6-66-612, etc., and are preferably copolymer-based ones, and in addition to these, there are also copolymerized ones with a component having an aromatic ring. Examples of those having an aromatic ring include terephthalic acid, isophthalic acid, fumaric acid, and others having substituents in the nucleus that do not contribute to the reaction. Among the above-mentioned copolymers, the above-mentioned aromatic ring is an example having a molecularly rigid portion, but there are also those having a highly branched hydrocarbon component saturated cyclo ring or a polar group. These have the effect of reducing crystallinity and improving elastic modulus, and the preferred upper limit of copolymerization is 30 mol%, preferably 20 mol% or less, but the above-mentioned film properties are also satisfied. It goes without saying that those who are chosen will be chosen.

Next is an ethylene-vinyl alcohol copolymer, the preferred ethylene content of which is 20 to 50 mol%.

More preferably, it is 30 to 45 mol%. Alternatively, it is a composition in which the copolymer is modified (mixed) with at least 40% by weight or less of at least one kind of polymer or copolymer selected from nylon resin ester resin and ionomer resin.

Next, 5 to 50% of polycarbonate resins, preferably those using monomers that lower the softening point or those copolymerized with these, can be used to form a film even when mixed with other types.
There is a mixture of 40% by weight, etc.

Next, copolymerized polystyrene resin, e.g.
Ingredients include acrylonitrile, acrylic ester, diene, etc. Preferred is acrylic ester.

Other examples include acrylic resins, vinyl chloride resins, vinylidene chloride copolymer resins, etc., but any other suitable resin may be used. Further, mixtures of other types of polymers, additives, plasticizers, auxiliary agents, pigments, or photic substances may also be used as long as they satisfy the above-mentioned characteristics.

These are ^STM-01525 (load 1 kg 2℃/
The final composition has a Vicat softening point of 40 to 150 (°C), preferably 50 to 130
('C), more preferably 60-120 ('C)
The one is good.

In addition, a polymer with poor quality or low crystallinity is preferable, but even a crystalline resin can be made into a low-height shape (crystallinity level of 30% or less) depending on the processing conditions, and the above characteristics can be satisfied. Good to have, for example polyethylene terephthalate resin. A preferable group of the above resins is polyester resins. Furthermore, not only single-layer films but also multi-layer films are preferably used as long as they satisfy the above-mentioned characteristics.

Further, the stretching may be carried out by a known method to a sufficiently high degree in the l-axis or bi-axis, and by a method that exhibits the above-mentioned properties.

Preferably, the stretching should be at least 2.5 times or more at as low a temperature as possible. Preferably it is biaxial.

Next, a specific mount that is releasably laminated with the above-mentioned film and brings about a synergistic effect by fully demonstrating the performance of the film is a convex mount that is to be adhered directly or indirectly to the above-mentioned film through an adhesive. The effective area ratio of the convex portion is
In the area effective for plate making, the ratio expressed in unit area is 1 to 35 (%), preferably 1 to 30 (%), more preferably 1 to 25%. If this value is below the lower limit, the ability to hold the film as a mount is insufficient. In addition, undesirable phenomena such as deformation or destruction of the convex portion or film due to the pressure applied during perforation, or a decrease in resolution and sensitivity due to movement of the film during perforation are likely to occur (
Become. If this value is above the upper limit, the heat required for perforation will be transferred from the convex portions, making it difficult to perforate the film effectively. Therefore, if the perforation energy is increased, the perforation in the non-contact area will expand and the resolution will decrease, and when the mount is peeled off during printing, the plate-made film will be likely to tear, the image will be cut out, etc. This leads to problems such as: For the above reasons,
The above-mentioned range is useful not only when applying to commonly known films with low heat sensitivity in terms of resolution, sensitivity, handling before and after plate making, etc., but also when particularly highly sensitive perforated films are advantageously used.

Next, the size of the convex portion is expressed as an area of 2.5 x 10-' to 1.44 x 10-'' (it is a crane, preferably 2.5
-"(m"), more preferably 10xlO-'
~6.40X10-'(ts''), more preferably 25.6X10-S~3.60X10-''(mm'').

Below the lower limit, there may be problems in manufacturing the protrusions, problems in adhesion between the film and the mount, deformation of the protrusions or the film due to pressure during drilling, and a decrease in resolution due to enlargement of the hole during drilling. You are more likely to have problems. Next, above the upper limit, the conduction of heat during perforation increases as the size of one convex part increases, making it difficult for heat to be conducted to the center, leaving a large unperforated area where it should be perforated, and as a result, when printing There is a tendency for the ink to not spread around, resulting in images and prints being chipped. In addition, the preferable relationship range between the size of the convex portion and the effective area ratio is expressed in order: (40X10-'ms
”, 35%) (7) Point (1,960×10-'
■The area is smaller than the straight line connecting the points of ``@'', 12.5%).
u'', 1%) and (1,960 x 10-5 mm!, 1
2.5%).

However, the vertical axis is the size of the convex portion (expressed in area).

) is expressed as the length of one side of a square, and the horizontal axis is expressed as a percentage of the effective area ratio.

Next, the height of the convex portion from the base must be at least 15 μm. The preferred range of this value is 25 μm or more, more preferably 30 μm or more. Although the upper limit is not particularly limited, it is approximately 500 μm. Below this lower limit, there may be problems with heat transfer, problems where the film in areas other than the convex parts adheres to the base part of the mount or its intermediate part due to deformation due to pressure during drilling, or concave parts caused by adhesive. As a result, the sensitivity and resolution are poor due to the problem of being buried. Above the above, there are problems in manufacturing, damage to the convex portion, bending, problems due to the thickness of the base paper, etc. -Next, the shape of the upper end of the convex portion is not particularly limited, but it may have an independent shape such as a round shape, an ellipse shape, a polygonal shape, a so-called gourd shape with a constricted center part,
Other options are possible, such as a short line. In addition, the cross-sectional view of the convex portion may have corners remaining or may be rounded.

However, in the latter case, the projected area of the part to which the adhesive is attached shall be converted to its area. Also, the intermediate part between the top and the base is not particularly limited, for example, even if it is vertical,
It doesn't matter if it's slanted, curvy, or fat.

It is preferable that these materials have substantially a single shape and a single size, but they may not be perfect to some extent and may be mixed.

Next, the shape of the arrangement is a regular arrangement! It is preferable to have a substantially constant spacing in order to ensure accurate drilling. Preferred examples include, for example, a mesh-like arrangement in which the vertical and horizontal directions are orthogonal, inclined, intersecting, and other arrangements.

Next, the base material that holds the convex portion and forms the mount may be made of the same material as the convex portion, or may be made of a different material.

The former includes those made of photosensitive resist material, embossed sheets, etched various materials, and the like.

The latter includes printing, resist, embossing, and etching on paper-like, film-like, sheet-like, and mesh-like base materials (for example, fabrics obtained from cellulose, synthetic fibers, etc., especially nonwoven fabrics, knitted fabrics, or paper). There are also those in which various materials are attached or bonded as protrusion forming materials using methods such as methods.

Preferably, convex portions are formed on a paper-like material (for example, synthetic paper, paper, etc.), a film, or a sheet-like base material (for example, polyester, polyvinyl chloride, polystyrene, etc.) by a printing method, a resist method, etc., or the above-mentioned material. Paper-like material laminated with thermoplastic resin and then embossed on that part, monolayer or multilayer thermoplastic resin sheet with embossed parts on the surface, and foam sheet embossed. Possible examples include those in which convex portions are formed using a foaming method.

The adhesive is usually selected from known adhesives, and the above-mentioned film and mount may be laminated using various methods in order to avoid destroying or deforming the image or text when peeled, considering the balance between adhesive strength and adhesive area. . Examples include reaction curing type, photocuring type, hot melt type, solvent type, emulsion/latex type, pressure sensitive type, and others.

The method of adhesion is to coat the film surface with a thin layer of adhesive or to coat it in spots, and then overlay the backing paper.
Any other suitable method may be used, such as adhesion, or coating an appropriate amount on the convex portions of the mount and overlapping the film with the adhesive.

The present invention consists of a base paper laminated with the above-mentioned film and a mount, preferably a high-sensitivity film is used as the film, and a synergistic effect with a specific mount provides high sensitivity and high resolution, and a low energy source is used. Moreover, the present invention relates to a base paper that can be used in a perforation method that effectively perforates thick film regions and does not require a porous support for image retention.

The perforation method that does not require a porous support means that the image or character is represented by a dot consisting of a large number of substantially independent perforations, and the image or character is not removed between the dots and is not easily handled.
The purpose is to form a state in which bridges are formed between the resin constituting the film, which is substantially regular and mesh-like to the extent that it can withstand operations such as printing. The resin bridge is reinforced by the resin that makes up the film aggregated during drilling. This relates to a method in which the perforated film itself is used as reinforcing ribs, in which perforation is carried out effectively with high sensitivity and no waste is generated due to perforation. This is possible for the first time through the synergistic effect of using a film with high sensitivity and good resolution, and using a specific mount in areas that are relatively thick and difficult to effectively perforate in the past.

The method of perforating is to overlay the document, in which images and characters are expressed as dots made of a material that absorbs light and generates heat, on the film surface, and then a high-energy flash of light (
It may also be used by irradiating it with a xenon lamp, etc.
In that case, there is a disadvantage that both the film and the mount must be made of materials that transmit light. It is also possible to consider a method in which the original is made of a light-transmitting material and the image thereon is illuminated from behind, but this method has the same problems as described above.

The method most suitable for the present invention has recently been developed using a so-called thermal head, which uses a lower heat source and has a large number of fine heating elements.
(Serial type, line type), the thermal head type described above with an array of LED laser elements etc. as optical elements, or the type that sends a laser beam to emit dot-shaped irradiation are suitable. There is.

〔Effect of the invention〕

The present invention uses a stretched film with specific performance, high sensitivity and high resolution, and uses a lower-energy perforation method than conventional methods. Furthermore, it is possible to create a specific shape in the thick region of the film, which was previously difficult to perforate. Only by using a mount having a range of characteristics can a synergistic effect be achieved to achieve perforation plate making with high sensitivity and high resolution, thereby providing a specific base paper capable of providing high quality printing.

The direct effects are (1) The perforation properties of the film can be further improved.

(2) The film can be handled in thick areas, has good operability, and is resistant to tearing and wrinkles.

(3) There is no need for an expensive porous support (to prevent image removal), which is advantageous in terms of cost and process.

(4) There is no need to firmly adhere a porous support to the film to prevent image deletion, and there is little reduction in thermal sensitivity or resolution due to adhesion.

(5) Since there is no need to use a porous support for printing, phenomena such as a decrease in resolution and white spots (poor ink circulation) caused by the support are less likely.

(6) A system using a normal thermal head, a head having an optical array (thermal transfer, thermal coloring method, etc.), etc. can be used as is, and there is no need for reverse imaging.

(If a porous support is laminated, unless the reverse image or mirror image is formed, the support side must be the printing surface, which causes various problems.) (7) Above +41. Because of (5), extremely fine printing is possible.

(8) Low-energy perforation is possible, and there is little deterioration of the base film.

(9) High-speed plate making can be achieved due to high sensitivity.

Ql Suitable for drilling with thermal heads, lasers, etc.

(Example) Examples will be shown below, but the present invention is not limited thereto.

Example 1 Mainly terephthalic acid as acid component, 1.4 cyclohexane dimetatool as alcohol component: 30 mol%
, a substantially amorphous copolyester consisting mainly of 0 mol% of ethylene glycolnia, etc. (Vicat softening point: 82°C, glass transition point: 81°C, density 1.2
7g/cs+3, intrinsic viscosity 0.75) at 90°C, vertical/horizontal ratio 4.0/4.0 (times)
This film was stretched to obtain a 7μ film.The properties of this film were as follows: heat shrinkage stress value of 500 g/Tsuru! (at 90°C and peak value), heat shrinkage rate near 9% (90°C) tensile modulus:
It was 220 kg/12 irises.

Next, as a mount, photocurable resist resin (commercially available)
was coated with a thickness of 100μ on top of the cover film, another cover film was placed on top of the cover film, and using various prescribed photo-masks, irradiation with ultraviolet rays was performed to cure the film, and the cover films on both sides were peeled off and washed. After curing, a mount having predetermined protrusions on the surface and a sheet made of the same resist on the bottom was prepared. Next, the convex portion was coated with a commercially available acrylic Elmazion adhesive using a roll coater so that the solid thickness after drying was approximately 1.5 μm, and the film was pressed to form a base paper.

Table 1 shows the characteristics of this product.

(Margin below) Next, after coating the film surface of this base paper with a silicone-based mold release agent, a thermal transfer type commercially available personal word processor (Casioward IIW-700; 24+' butts x 2
4) Remove the transfer ink tape cassette (with a printing performance of 20 characters/sec) and set it so that the film surface of the base paper is in contact with the thermal head, and adjust the print density. and directly test pattern (
Perform plate making (including solid areas and character areas), and use a stencil printing machine (
After winding it around a printing drum of Riso Kagaku ■Risograph 7200E), the mount and film were peeled off, printing was performed at a printing speed of 120 sheets/min, and observations were made before and after.

As a result, in order to adjust the perforation state after plate making of RunNcLl~8, we observed the solid print area of the mount and the peeled film with a microscope, and in both cases we found that the dot area roughly corresponds to the energy given to the thermal head during feeding. It had effective perforations and a mesh-like rib structure between them, and had a structure that would ensure that both solid images and character images would not fall off. Even when the mount was peeled off, the cutout did not fall off, and the rib structure remained almost undamaged even after printing 2,000 sheets using this printing machine. Furthermore, there was no image distortion due to film deformation.

In addition, the printed matter is clear, with no white spots (areas where the ink does not go around due to clogged images or characters) and black spots (images or characters).
For areas other than the literature section where the film is damaged or where the ink has gotten into the thin ribs of the image area reinforcing it, please write the equivalent of 1200 characters or images on A-4 size paper. Even when printed, it was clear and did not interfere with legibility, and was comparable to a copy made using a 20-dot laser printer that uses an electrostatic toner. When the printed paper was observed under a microscope, it was found that in the case of the one-toner type, a large amount of fine toner powder was scattered and adhered to the white area of the non-image area, especially around the image periphery.
In the case of the above-mentioned ink according to the present invention, ink did not adhere to areas other than the image at all.

Also, Run1lh2 has 150 mesh as a mount.
The sensitivity was better than when layers of gauze (made of polyester fabric with a diameter of 50 μm) were layered.

Next, the one with Run Na ratio has a large convex part on the mount.
It has a diameter of 30 μm and corresponds to an effective area ratio of 20%,
Because it is too large, the perforation heat does not circulate around the unperforated part, which is slightly smaller than the above size, and the regular rib structure of the thermal head connects the thin random sushi-shaped resin to the unperforated part, or both. There are many cases where mismatching of positions occurs, and places that should be drilled by the thermal head are not drilled or are deformed.
Images and characters on printed materials often have missing or cut white areas, making it difficult to produce clear printed materials.

Furthermore, the sensitivity of the film was greatly reduced, and even when the energy of the thermal head was set to maximum, the aperture ratio was only about 30% of the area where the holes should be drilled. Furthermore, for comparison, the same base paper using a commercially available stretched polyester film (crystallinity = 48%, mp: 258°C) of 2 μm was hardly perforated.

In the case of Run Nl ratio 2, the convex portion of the mount has a diameter of 90 μm and the effective area ratio is equivalent to 40%, and has the same tendency as Comparative Example 1 above, and the convex portion size is small in some cases, but on the contrary, Since the area ratio was large, the tendency was worse. The aperture ratio similar to the above was about 15 to 20%, and the current situation was that the printed matter was scummed.

From the above, it is clear that a base paper with a poor support is effective in combination with a film having the characteristics of the present invention and a specific mount.

Example 2 As a film material, a film having the characteristics shown in Table 2 was obtained using the same copolymerized polyester as in Example 1 in the same manner as in Example 1, by appropriately selecting the stretching temperature, stretching ratio, and film thickness. (R
unljla9-11) Next, a polyester having a low melting point containing 5 mol % of isophthalic acid in terephthalic acid as an acid component and using ethylene glycol as an alcohol component was processed in the same manner as above to obtain a film having the properties shown in the table. (Run welcome 12). Similarly, a film made of polyethylene terephthalate according to the same table was obtained. (Run
tlla13).

Similarly, a film made of nylon 6-12 copolymer resin (RunNa 14 ), a film made of ethylene-vinyl alcohol copolymer (39 mol% ethylene copolymerized) resin (RunNa 15 ),
A base paper was prepared in the same manner as in the case of RunN112 in Example 1 using the same mount.

(Hereinafter, blank space) Note that the Run Na ratio of 3 means that polyethylene terephthalate is rapidly cooled to form a raw film, which is stretched and heat-treated to have a crystallinity of about 35%. Assimilation 4 uses polypropylene copolymerized with 3 wt% ethylene (mp 145°C, Vicat softening point: 125°C), and Assimilation 5 uses ethylene vinyl acetate copolymer with a vinyl acetate group content of 10 wt% (MI: 1.Olmp, 93℃, crystallinity 42%,
Vicat softening point 76℃) Assimilation 6 has a vinyl chloride content of 1
A 5wt% vinyl chloride-vinylidene chloride copolymer was used and heat treated to stabilize the dimensions after stretching.

The above base paper was processed using a thermal transfer type commercially available personal word processor (Cannon Word Mini CM-8: 24 x 24
Using F button 20 characters/5ec) in the same manner as in Example 1,
A perforation plate making test was conducted. As a result, Run Na9~
Sample No. 15 could be effectively perforated as in Example 1, and performed similarly well in the same printing test. Films with a thickness of 5 μm tended to be somewhat stiff and required careful handling, but could be used within the energy level adjustment range of the thermal head.

Among them, Run N19 has a drilling energy level M
ax, Run Nail 0. 11 is 315 in its eyes, Run Na 12 is 415, R
Un Nl 13 was well drilled at the same level of 415 for Max's Run11h14, and 415 for Run flh 15.

With a Run NkL ratio of 3, even at the maximum energy level, holes were hardly perforated effectively, and when expressed using the above-mentioned aperture ratio, it was about 5 to 10%, which was at a level where the image could hardly be distinguished even when printed.

In addition, the plate peeled off from the mount after making the plate, and the parts exposed to heat history were prone to tearing.

With a Run Nn ratio of 4, the elastic modulus of the film is low and it is difficult to handle, and even at maximum energy, the perforation is poor and it is easy to stick to the thermal head, and the porosity is about 10%, and the holes are also difficult to handle. It was easy to spread out and form a spider web. Also, during printing, it was easy to tear during the process of peeling off the backing paper, and even after printing, it was easy to wrinkle and deform.

With a Run Nn ratio of 5, the film was very soft and easily torn, and even at the maximum energy, only about 5% of the holes were perforated, the holes were easy to expand, and the film was torn to pieces when peeled off from the backing paper.

R (111Na ratio 5 means that the film is soft and will hardly perforate effectively even at the maximum energy, and the degree of this is 1
It was about 0-15%. In addition, it was easy to stick to the thermal head, causing tearing, enlarged holes, unevenness, and tearing when peeled off from the mount.

Furthermore, when used many times, the debris adhering to the thermal head tends to break down and become stuck.

Example 3 Using the RunNa2 film of Example 2, an adhesive layer was coated on a 25μ polyester film (stretched and heat set) as a mount, and the convex pattern of RunNa2 of Example 1 was resisted on top of it. A base paper was created in the same way using the one produced by the method as a mount (Ru
n Na 16), using a film similar to Run Nl 16, then 80 made of the same material as the film.
A 120 mesh Tetron gauze was layered on a μm unstretched sheet under heating, and embossing was performed on the rubber sheet to create a mesh-like uneven pattern on the other side.The protrusions were approximately oval in shape. The ratio of the major axis to the minor axis is 1:4,
The effective area ratio of the convex portions was approximately 10%, the area of each convex portion was approximately 500 x lO-' (■l), and the height of the convex portion was 65 μm. Using this as a mount, the base paper was (Run Na L 7 ).

All of the above plates were subjected to a perforation test in the same manner as in Example 2, and as a result, good plates could be made in all cases, and the results of the printing test were also good.

Comparative Example 1 Using the film and dimensions of Example 1, the basis weight was 8.5 as a mount.
g/m” tissue paper (Run Nl ratio 7
) Made of kraft paper with a basis weight of 60 g/m (Run
Na ratio 8) 200 mesh polyester (40
Coat the acrylic emulsion on the film surface using gauze (Run Na ratio 9) as an adhesive to a dry weight of approximately 2 to 3 g/m''. Then, the above-mentioned mounts were stacked and laminated.

These base papers were subjected to the same thermal head as in the example. The Run flh ratio of 7 is, for example, the Run flh ratio of the present invention.
Its sensitivity is significantly lower than that of Na2, and the aperture ratio is 2.
0 to 30%, and the shape corresponding to the convex part is random, so the mesh-like accurate perforation by the thermal head is not done completely (unevenly), the aforementioned rib structure is not seen, it is irregular, and there are no cracks. If the string-like part that was about to break during handling or printing and the part that should be perforated corresponded to the dense part of the thread, it would be blocked so that the ink could not pass through.Remove the backing paper and film. When printing, the film was easily torn, and the printed images were prone to the aforementioned white and black marks in various places.

Next, in the case of a Run Nl ratio of 8, no pores were observed and this did not pose a problem. This seems to be because the heat from the thermal head is absorbed and the film cannot move. Randomly sprinkling powder or the like between the film and the paper was not very effective.

Next, in the case of a Run Na ratio of 9, the projected part of the sensor is filled with adhesive, and the sensitivity is greatly reduced.The film has an independent mesh-like opening, and the film at the adhesive part is fixed over a wide area. Possible reasons include that the holes are not drilled due to heat transfer, lack of movement, etc., and the drilling sensitivity and accuracy of drilling in the portion corresponding to the thermal head were inferior to the case of the present invention.

Therefore, when perforation is performed by simply stacking the layers without adhesion, the sensitivity improves somewhat, but it is still inferior to the present invention. In this case, the film was prone to shifting, distorting the image, and widening the perforations, resulting in inaccuracies. The film of the present invention is a high-sensitivity film, and it is better to have contact in a relatively thick region (within the scope of the claims of the present invention) and at a convex portion as in the present invention, if only for the heat insulation effect. At the time of perforation, the perforation at the next position on the film is (
Because there is less movement (e.g., the front, rear, left, and right holes interfere with each other, causing the hole to be skewed to one side or the other), the shrinkage stress necessary for drilling is concentrated uniformly, and it is believed that sensitivity is improved and accurate drilling is performed. It will be done.

Claims (1)

[Claims] The heat shrinkage stress value is at least 75 (g/mm^2), the heat shrinkage rate is at least 30 (%), the tensile modulus is at least 75 (kg/mm^2), and the film thickness is 4 to 18 μm.
The effective area ratio of the stretched film made of a thermoplastic resin and the convex parts that should be in direct or indirect contact with the film in the effective part of the plate is 1 to 35%, and the area per piece is 2.5%. ×10^-^5～1.44×10^-^2
(mm^2), has a height of at least 15 μm, and is composed of a mount having convex portions with a regular arrangement, both of which prevent substantial damage to the image during printing after plate making. High-resolution, high-sensitivity, heat-sensitive perforated base paper characterized by being removably laminated.