JP2552662B2 - Original drawing film for projection - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a projection original drawing film capable of forming an image in either a heat-sensitive system or an electrophotographic transfer system, and further capable of repeatedly reversible image formation and image erasing in the case of the heat-sensitive system.

2. Description of the Related Art In recent years, an overhead projector has been widely adopted as a means for transmitting information in various fields. As is well known, an overhead projector is an optical device for enlarging and projecting an image of a projection original drawing (an image formed on a projection original drawing film). Conventionally, the projection original drawing film used for this is (a) transparent. (A) A plastic film alone, (b) a heat-shrinkable plastic film coated and permeated with a penetrant, (c) a non-shrinkable or low-shrinkable polypropylene film or polystyrene film as a material, (d) ) It is known that a layer of a thermochromic substance or a thermofoaming substance is inserted between two plastic films having different heat shrink temperatures, and (e) a plastic film containing or coating the thermochromic substance. There is. When obtaining originals from these original drawing films, in the case of the original drawing film in (a), a colored image is formed by handwriting using a special drawing material, and in the case of other original drawing films, the original is overlaid on it to form a film. Infrared irradiation is performed from the side to heat-soften, heat-shrink, or heat-color the film portion corresponding to the original image, thereby forming a fine uneven pattern or a colored image.

However, all of the conventional original drawing films for projection have poor thermal sensitivity, poor contrast and resolution of a projected image, and cannot be used repeatedly, so that there is a drawback that the original drawing becomes expensive.

Furthermore, in recent years, a method of transferring a toner image onto a projection original drawing film using an electrophotographic transfer method has been carried out, but the original image obtained in this way has a transparent support,
The images are difficult to see, and it is difficult to determine whether the exposure is over or under.

The purpose of the present invention is to have a high thermal sensitivity when the original image is created by a heat-sensitive method, has excellent resolution in the contrast of the projected image, and can be used repeatedly, and is exposed when the original image is created by the electrophotographic transfer method. It is an object of the present invention to provide an original drawing film for projection in which excess and deficiency can be easily determined.

Structure The projection original drawing film of the present invention generally comprises, as shown in FIG. 1, a resin base material on one surface of a transparent support, and an organic low-molecular substance dispersed in the resin base material as main components,
The heat-sensitive layer 2 whose transparency reversibly changes depending on temperature is provided, and the conductive layer 3 is provided on the other surface. When the heat-sensitive layer is made to have a self-supporting property as a heat-sensitive film or sheet, the transparent support can be omitted.

When the heat-sensitive system is applied to the projection original drawing film of the present invention, reversible image formation and image erasing action due to temperature enable repeated actions. The principle of image formation and image erasure in this case will be described with reference to the drawing. In FIG. 2, the heat-sensitive layer mainly composed of the resin base material and the organic low molecular weight substance dispersed in the resin base material is, for example, T ₀ or less. It is cloudy and opaque at room temperature. When this is heated to a temperature between T _{1 and} T ₂ , it becomes transparent, and even if it is returned to room temperature below T ₀ in this state, it remains transparent. Further heating to a temperature of T ₃ or higher results in a semi-transparent state intermediate between maximum transparency and maximum opacity. Next, when this temperature is lowered, it will not become transparent again,
It returns to the initial cloudiness and opacity. When the opaque state is heated to a temperature between T _{0 and} T ₁ and then cooled to room temperature, that is, a temperature lower than T _0, a state between transparent and opaque can be obtained. Also, the transparent material that has become transparent at room temperature is heated to a temperature of T ₃ or higher again, and returns to room temperature to return to a cloudy opaque state. That is, both opaque and transparent forms at room temperature and intermediate forms thereof can be adopted.

Therefore, for example, after heating the entire transparent original film having such a heat-sensitive layer to a temperature between T _{1 and} T ₂ , it is cooled to a room temperature of T ₀ or lower to be transparent, and then partially heated by a thermal head or the like to T ₃ If you heat it to the above temperature and make that part opaque,
A white image is formed.

Also, after heating the entire original film to a temperature of T ₃ or higher, it is returned to room temperature of T ₀ or lower to make it cloudy and opaque, and then partially heated to a temperature between T _{1 and} T ₂ such as a thermal head When is transparent, a transparent image is formed on the white surface.

The image formation and erasure on the heat sensitive layer as described above can be repeated at least about 10 ⁴ times.

On the other hand, when the electrophotographic transfer system is applied to the projection original drawing film of the present invention, a toner image can be formed as in the conventional case. In this case, after making the entire original drawing film opaque as described above, the toner image is transferred and fixed on the conductive layer surface using an electrophotographic copying machine, and then the obtained entire opaque original drawing is made transparent as described above. For example, a transparent original map can be obtained.

Next, a method for forming each layer of the original drawing film for projection of the present invention and materials used will be described.

First, the heat-sensitive layer is generally prepared by 1) dissolving a resin base material and an organic low-molecular substance in a solvent and coating and drying this on a transparent support, or 2) dissolving the resin base material in a solvent that dissolves only the resin base material. It is formed by dispersing an organic low molecular weight substance in the form of fine particles therein by various methods, and coating and drying the fine particles on a transparent support. Alternatively, when the heat-sensitive layer is made to be self-supporting (in this case, the support is not necessary), it is formed by heating, melting and kneading the resin base material and the organic low molecular weight substance, and molding this into a film or sheet. It The thickness of the heat-sensitive layer or film thus formed is preferably about 5 to 50 μm. The thickness of the heat-sensitive layer or film must be 10 μm or more in order to obtain a particularly high-contrast image. In any case, in the formed heat-sensitive layer or film, the organic low molecular weight substance exists as a fine particle in the resin base material in a dispersed state.

The resin base material used for the heat-sensitive layer forms a film or sheet in which an organic low-molecular substance is uniformly dispersed and held,
It is a material that affects the transparency at maximum transparency. Therefore, the resin base material is preferably a resin having good transparency, mechanical stability, and good film forming property. Such resins include polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-vinyl alcohol copolymer, vinyl chloride-vinyl acetate-maleic acid copolymer, vinyl chloride-
Vinyl chloride-based copolymers such as acrylate copolymers; polyvinylidene chloride, vinylidene chloride-vinyl chloride copolymers, vinylidene chloride-copolymers such as vinylidene chloride-acrylonitrile copolymers; polyesters; polyamides;
Examples thereof include polyacrylate, polymethacrylate, acrylate-methacrylate copolymer, and silicone resin. These may be used alone or as a mixture of two or more.

On the other hand, the organic low molecular weight substance may be appropriately selected according to the temperature T _{0 to} T ₃ shown in FIG.
C., especially about 50 to 150.degree. C. are preferred. Alkanols; alkane diols; halogen alkanols or halogen alkane diols; alkylamines; alkanes; alkenes; alkyls;
Halogen alkanes; Halogen alkenes, Halogen alkynes; Cycloalkanes; Cycloalkenes; Cycloalkynes; Saturated or unsaturated mono- or dicarboxylic acids or their esters, amides, or ammonium salts; Saturated or unsaturated halogen fatty acids or their esters, amides, Or ammonium salt; allylcarboxylic acid or ester, amide or ammonium salt thereof; halogen allylcarboxylic acid or ester, amide or ammonium salt thereof; thioalcohol; thiocarboxylic acid or ester, amine or ammonium salt thereof; thioalcohol And the like. These may be used alone or in combination of two or more. The carbon number of these compounds is preferably 10 to 60, preferably 10 to 38, and particularly preferably 10 to 30.
The alcohol group in the ester may be saturated or unsaturated, and may be halogen-substituted. In any case, the organic low molecular weight substance is at least one of oxygen, nitrogen, sulfur and halogen in the molecule, such as --OH,
-COOH, -CONH, -COOR, -NH - , - NH 2, -S -, - S-
A compound containing S-, -O-, halogen or the like is preferable.

More specifically, these compounds include higher fatty acids such as lauric acid, dodecanoic acid, myristic acid, pentadecanoic acid, palmitic acid, stearic acid, behenic acid, nonadecanoic acid, arachidic acid and oleic acid; methyl stearate,
Esters of higher fatty acids such as tetradecyl stearate, octadecyl stearate, octadecyl laurate, tetradecyl palmitate and docosyl behenate; C ₁₆ H ₃₃ -O-C ₁₆ H ₃₃ , C ₁₆ H ₃₃ -S-C ₁₆ H ₃₃ , _{C 18 H 37 -S-C 18} H 37, C 12 H 25 -S-C 12 H 25, C 19 H 39 -S-C 19 H 39, C 12 H 25 -S-S-C 12 H 25, Etc., such as ether or thioether.

As the solvent, an organic solvent such as tetrahydrofuran, methyl ethyl ketone, methyl isobutyl ketone, chloroform, carbon tetrachloride, ethanol, toluene or benzene is appropriately selected and used.

The weight ratio of the organic low molecular weight substance to the resin base material in the heat sensitive layer is preferably about 1: 0.5 to 1:16. If the ratio of the resin base material is less than this, it becomes difficult to form a film in which the organic low molecular weight material is retained in the resin base material, while if it is higher than this, the amount of the organic low molecular weight material is small, so that it is opaque. Becomes difficult.

The conductive layer is then generally on the side of the transparent support opposite the heat-sensitive layer,
It is formed by applying and drying an aqueous solution in which a conductive material and, if necessary, a highly insulating resin are dissolved or dispersed in water. The thickness of the conductive layer thus formed is preferably about 0.5 to 5 μm. The surface resistivity of the conductive layer is preferably about 10 ⁸ to 10 ¹⁴ Ω.

As the conductive material used for the conductive layer, all conventionally known materials can be used, and examples thereof include the following compounds.

1) Polymer Electrolyte Cationic: Polyvinylbenzyltrimethylammonium chloride, polydimethyldiallylammonium chloride, poly (2-methacryloyloxyethyltrimethylammonium chloride) polyethyleneimine hydrochloride, poly (2-acryloxyethyldimethylsulfonium chloride), poly (Glycidyltributylphosphonium chloride), etc. Anionic system: poly (meth) acrylic acid and its salts, polystyrenesulfonic acid and its salts, polyvinylsulphonic acid and its salts, alginates, styrene-maleic acid copolymers, etc. Polyethylene glycol, etc. 2) Inorganic salts NaCl, NaNO ₃ , Na ₂ SO ₄ , LiCl, CaCl ₂ , KCl, etc. 3) Conductive pigments Silver iodide, copper iodide, copper sulfate, tin oxide, indium oxide,
Zinc oxide, metal powder such as aluminum powder 4) Low resistance resin Water-soluble resin: PVA, starch, CMC, polyvinylpyrrolidone, polyacrylamide, etc. Oil-soluble resin: Nylon 66, etc. 5) Surfactant Cationic system: dichloride Stearyl dimethyl ammonium chloride,
Stearylbenzyldimethylammonium chloride chloride, etc. Anionic system: Sodium alkylsulfate, triethanolamine alkylsulfate, etc. Nonionic system: Lauric acid diethanolamide, ethylene glycol distearate, isopelopill myristate, etc. Amphoteric system; cocoamidopropyl betaine etc. 6) Others Alumina sol, As the highly insulating resin used for the conductive layer such as hectorite clay, a resin having a surface specific resistance of 10 ¹⁵ Ω or more such as vinyl acetate resin, ethylene-vinyl acetate copolymer and the like is used.

 The present invention will be described below with reference to examples.

 All parts are parts by weight.

Example 1 Acrylic resin having a quaternary ammonium group (Sebyan 46793 manufactured by Daicel) 3 parts Vinyl acetate resin (Sebian 4150 manufactured by Daicel) 7 parts Water 20 parts A component sufficiently mixed to form a polyester film having a thickness of 75 μ One side was coated with a wire bar and dried at 90 ° C. to form a conductive layer having a thickness of 1.5 μm. The surface resistivity of this conductive layer was 3 × 10 ¹¹ Ω. Next, hebenic acid 5 parts Vinyl chloride-vinyl acetate copolymer (UCY VYHH) 20
Part Tetrahydrofuran 75 parts of a component are mixed and uniformly dissolved, coated on the other side of the polyester film with a wire bar, dried at 100 ° C. to form a heat-sensitive layer having a thickness of 14 μ, and the whole is white and opaque. An original drawing film was created.

Next, a black toner image was transferred onto the conductive layer surface of the original film thus obtained using an electrophotographic copying machine (FT-4060 manufactured by Ricoh), and then heat-fixed. As a result, in this heat fixing step, the whole original film was heated to a temperature of about 180 to 190 ° C., but the heat sensitive layer remained opaque white even after returning to room temperature.
Therefore, an opaque original image having a clear black image on a white background was obtained. Since this original image is a white background like plain paper, the image is easy to see, and therefore, an appropriate exposure amount can be easily selected.

Next, after heating the whole opaque original image to 70 ° C. and returning it to room temperature, the whole heat-sensitive layer became transparent, and as a result, a transparent original image for projection was obtained.

Further, when the whole of the white opaque original drawing film prepared in this example was heated to 70 ° C. and then returned to room temperature, the heat-sensitive layer became transparent, and the whole became a stable original drawing film. Next, when the image was heated from the heat-sensitive layer side of this transparent original image with a thermal head at a heat energy of 1 mj, the heated portion became white and opaque, and as a result, a transparent image for projection having a white image on a colorless transparent background. The original map was obtained.

Next, when the original image for projection by the electrophotographic copying machine and the original image for projection by the thermal head obtained as described above were respectively projected by the overhead projector, a clear dark image with high contrast and high resolution was formed on the screen. Was done. After heating the entire projection original image having a white image by this thermal head to 70 ° C. and then returning it to room temperature, the white image was erased and the whole original image film was returned again. When the transparent original image film was printed again by using a thermal head, a white opaque image was formed, and an original image for projection was obtained again.

Example 2 Acrylic resin having a quaternary ammonium group (7 parts as in Example 1) Vinyl acetate resin (as in Example 1) 3 parts Silica 0.5 parts Water 19.5 parts An entirely opaque original drawing film was prepared in the same manner as in Example 1. The surface resistivity of the conductive layer of this film was 1 × 10 ⁹ Ω.

Then, a black toner image was transferred onto the electroconductive layer surface of the original film by the same electrophotographic copying machine as in Example 1 and heat-fixed. As a result, an opaque original image having a clear black image on a white background was obtained.

Next, the whole opaque original image was heated to 70 ° C. and then returned to room temperature, so that the whole heat-sensitive layer became transparent, and as a result, a transparent original image for projection was obtained.

Also, when the whole white opaque original drawing film prepared in this example was heated to 70 ° C. and then returned to room temperature, the heat-sensitive layer became transparent, and the whole became a stable original drawing film. Next, when an image was heated from the heat-sensitive layer side of this transparent original film using a thermal head in the same manner as in Example 1, the heated portion became white and opaque, and as a result, a white image was formed on a colorless transparent background for projection. A transparent original map was obtained.

When an original projection image by an electrophotographic copying machine and an original projection image by a thermal head obtained as described below were projected by an overhead projector, respectively, a clear dark image having high contrast and high resolution was formed on the screen.

Example 3 As a conductive layer formation, the same procedure as in Example 1 was repeated except that an ethylene-vinyl acetate copolymer (Sumikaflex 4000 manufactured by Sumitomo Chemical Co., Ltd.) 8 parts Polyvinylbenzyltrimethylammonium chloride 2 parts Water 20 parts was used. Produced an original drawing film for opaque projection. The surface resistivity of the conductive layer of this film was 1 × 10 ⁹ Ω.

Thereafter, a black toner image was transferred to the conductive layer surface of this original film by the same electrophotographic copying machine as in Example 1 and heat-fixed, whereby an opaque original image having a clear black image on a white background was obtained.

Then, the whole opaque original image was heated to 70 ° C. and then returned to room temperature, so that the whole heat-sensitive layer became transparent, and as a result, a transparent original image for projection was obtained.

Further, when the whole of the white opaque original drawing film prepared in this example was heated to 70 ° C. and then returned to room temperature, the heat-sensitive layer became transparent, and the whole became a stable original drawing film. Next, when an image was heated from the heat-sensitive layer side of this transparent original film using a thermal head in the same manner as in Example 1, the heated portion became white and opaque, and as a result, a white image was formed on a colorless transparent background for projection. A transparent original map was obtained.

Next, when the original projection image by the electrophotographic copying machine and the original projection image by the thermal head obtained as described above were respectively projected by the overhead projector, a clear dark image with high contrast and high resolution was formed on the screen. It was

Effect As described above, since the original drawing film for projection of the present invention uses the thermal transparency change of the heat-sensitive layer for image formation and judgment of the exposure amount, when the original drawing is created by the heat-sensitive method, the heat sensitivity is high and the contrast of the projected image is high. Since it is excellent in resolving power and capable of reversible image formation and erasure, it can be used repeatedly and is very economical. Since a white opaque original image can be obtained, the image is much easier to see than a conventional transparent original image, and therefore, there is an advantage that it is easy to judge whether the exposure is excessive or insufficient.

[Brief description of drawings]

FIG. 1 is a block diagram of an example of the original drawing film for projection of the present invention, and FIG. 2 is an explanatory diagram of an image forming and erasing principle in a heat-sensitive layer of the original drawing film for projection of the present invention. 1 ... Transparent support, 2 ... Thermosensitive layer 3 ... Conductive layer

Claims (1)

(57) [Claims] 1. A transparent base material comprising, as a main component, a resin base material and an organic low molecular weight substance dispersed in the resin base material on one surface thereof, and the transparency reversibly changes depending on temperature. A projection original drawing film having a heat-sensitive layer and a conductive layer on the other surface.