JPH0237309B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to improvements in pressure-sensitive materials having a pressure-sensitive microcapsule coating layer, particularly with new stilt materials. A large number of pressure-sensitive substances have been known so far. For example, it has a coating layer of microcapsules containing various substances such as ink, fragrance, coloring agent, catalyst, etc., and exhibits pressure-sensitive properties such as coloring and scenting when the microcapsules are destroyed. . In particular, pressure-sensitive copying paper has a long history and is the most widely industrialized paper. In general, electron-donating organic coloring agents such as triphenylmethane dyes such as crystal violet lactone and leuco dyes such as benzoyl leucomethylene blue, clay minerals such as acid clay, activated clay, and attapulgite, and phenol formaldehyde condensates, Pressure-sensitive copying paper that applies the principle of color development through the reaction of electron-accepting coloring agents such as phenols, aromatic carboxylic acids, or their metal salts can be produced using phase separation methods, interfacial polymerization methods, in-situ methods, etc. Top paper (CB) coated on one side of the microcapsule support substrate containing a coloring agent made by the method of Cordled paper (CFB), in which capsules and coloring agents coated on different sides of the same substrate, are being put into practical use in appropriate combinations. There is also a type of paper called a single coloring paper in which a capsule coloring agent is coated on the same side. One of the important properties required of such pressure-sensitive copying paper is that it is capable of producing clear, high-density colored images during copying, but also that One example is that it does not cause unnecessary colored stains. In order to satisfy these required characteristics, the microcapsules themselves must have sufficient mechanical strength such as pressure resistance, abrasion resistance, and impact resistance, as well as the ability to develop vivid colors. However, in reality, no microcapsule itself has been found to have such required characteristics. Therefore, as a means to improve the pressure resistance and abrasion resistance of such pressure-sensitive copying paper, particulate matter larger than the microcapsule particle diameter has been dispersed as a stilt substance, that is, a buffer, during the coating of the microcapsules. However, a method has been adopted in which the protruding stilt material supports the unintentionally applied weak pressure, thereby reducing capsule rupture. Among the substances proposed as this stilt material, the one that has been widely used in the past is US Patent No.
Cellulose fiber described in No. 2711375, Special Publication No. 1971-
The starch particles described in No. 1178, and other stilt substances described in various patents include inorganic pigments, fine particles of natural polymer substances, fine particles of synthetic polymer substances made by methods such as suspension polymerization or mechanical crushing. (U.S. Pat. No. 3,625,736), aggregates of polymer particles treated near the Tg point (JP-A-51-78422), microspheres (JP-A-48-32013), dye-free capsules (JP-A-Sho 48-32013), 47-20972) and grape-like lumps of pigmentless fine particles (Japanese Patent Application Laid-Open No. 143325/1982), each of them has drawbacks and is not necessarily in a satisfactory state. For example, when using mechanically crushed inorganic pigment particles or natural or synthetic polymeric substances as the stilt material, these normally available powders have a wide particle size distribution, so the particle size is approximately 1.5 times the capsule particle size. When using powder with a relatively small average particle size, it contains a considerable proportion of particles smaller than the capsule particle size, which is not effective in improving pressure resistance, and this inhibits the transfer of capsule oil to the color developing layer, resulting in color development. This results in poor copy paper. On the other hand 3
When using a powder with a relatively large average particle size of around twice the size, although it is effective in improving pressure resistance, the coarse particles contained in some parts cause the surface of the paper to become rough, and the particles themselves do not have adhesive properties. In some cases, the bonding strength between the particles, between the particles and the supporting substrate, and between the particles and the microcapsules is lacking, and the particles can be removed from the coated surface by applying friction, and sand is inserted between the capsule surface and the color developing surface and friction is applied. A similar phenomenon occurs, resulting in copy paper with very poor abrasion resistance. In addition, when microspheres or dye-free capsules are used as stilt materials, because their cores are hollow or oil droplets, they collapse under relatively weak pressure, and the expected effect of improving pressure resistance is not observed. . In addition, in the case of cellulose fibers, the viscosity of the prepared paint is higher than that of other stilt materials such as starch, and the fluidity is significantly poorer, so a very high air pressure is required when applying with an air knife. shall be. In addition, classified starch particles, suspension polymer particles of synthetic polymers such as polystyrene, polyvinyl chloride, polyvinyl acetate, polyolefin made by artistic means, or JP-A-51-78422 When using aggregates of polymer particles made by the method described above, these particles have a relatively sharp particle size distribution, so it is possible to produce copying paper with vivid color development and excellent pressure resistance. However, as in the case of the inorganic pigment fine particles,
The particles themselves have no adhesion ability, or even if they do, it is very weak, so they have the disadvantage of poor abrasion resistance. For this reason, a method of improving the abrasion resistance by combining starch particles with an adhesive has been proposed (Japanese Patent Publication No. 48-33204), but this is accompanied by a reduction in coloring ability due to the addition of the adhesive. Moreover, since synthetic polymers such as polystyrene, polyvinyl chloride, and polyvinyl acetate are made from petroleum, they are extremely costly. Also, as a stilt material
- When the grape-like aggregates of inorganic pigment fine particles described in No. 143325 are used, the specific gravity of the particles becomes close to the specific gravity of the inorganic pigment used, and the specific gravity of the granules is close to 2.6, such as the kaolin exemplified in this patent. The disadvantage of using pigments having the following properties is that during successive application of capsule coating liquids, the proportion of stilt substances in the coating liquid gradually increases due to the classification effect. The object of the present invention is to use a novel stilt material that does not have the above-mentioned drawbacks, and to achieve high-quality pressure-sensitive properties that effectively prevent the development of pressure-sensitive properties due to unintentional destruction of microcapsules, such as color development and odor generation. It is to provide the substance. The pressure-sensitive material of the present invention is characterized in that particulate amylose clathrate compounds are scattered as a stilt material in the microcapsule coating layer and/or the paint coating layer that comes into contact with the microcapsule coating layer. The amylose clathrate compound is a complex formed by amylose containing various substances within its helical structure, and is generally known as an undesirable crystalline substance that precipitates in the starch size solution during preparation and storage. It is being The present invention focuses on the characteristics of amylose clathrate compounds, which have been avoided in the past because they impair the uniformity of starch and reduce its effective starch concentration.
The object of the present invention has been achieved. Unlike simple stilt substances such as starch, amylose clathrate compounds have a uniform particle size and are excellent in water resistance, solvent resistance, and heat resistance, so they can be effectively used as stilt substances in a wide range of applications. can be provided. The amylose clathrate compound may be used alone, but by using it together with a paste-like substance that is a by-product during its production, the paste-like substance serves as an adhesive for the coating layer in which the amylose clathrate compound is scattered. be able to. Amylose clathrate compounds are obtained by gelatinization modification of starch, that is, by gelatinizing and fluidizing starch, and recrystallizing amylose therefrom. Examples of this method include simple gelatinization of starch, oxidative modification, Hydrolysis by acid, alkali, and heat, and enzyme denaturation by enzyme preparations are known, but the particle size can be adjusted depending on the processing time of gelatinized starch, the amount of amylose component in the starch, and the type and amount of additives. Can be done. Next, the oxidative denaturation method and the enzymatic denaturation method will be briefly explained as particularly preferred methods for producing amylose clathrate compounds. In the oxidative modification method, an oxidizing agent and a fine particle formation promoter are added to starch slurry and heated.
Amylose clathrates are effectively formed. As the oxidizing agent, peroxides such as ammonium persulfate and hydrogen peroxide are preferably used, and as the fine particle formation promoter, ethers of alcohols having 1 to 22 carbon atoms, such as polyoxyethylene lauryl ether, polyoxyethylene oleyl ether, Esters of fatty acids having 1 to 22 carbon atoms, such as methyl stearate, polyoxyethylene laurate,
Sulfate salts of alcohols having 1 to 22 carbon atoms, such as sodium lauryl alcohol sulfate, sodium stearyl alcohol sulfate, and fatty acids having 1 to 22 carbon atoms and their salts, such as stearic acid, lauric acid, calcium stearate, stearic acid Those selected from the group of ammonium and sulfate group-containing chemicals and other known inclusion compound formation promoting substances are preferably used. For example, by adding the above-mentioned oxidizing agent and fine particle formation promoter to a slurry of starch dispersed in water,
such as autoclaves and jet trucks.
After gelatinizing and modifying the starch using a heating device that can heat it to over 100°C, a portion of the starch solution can be grown into fine amylose crystal particles, that is, amylose clathrate compounds, by maintaining the starch paste at 80° to 90°C. can. In addition, in the enzyme denaturation method, an enzyme, a fine particle production promoter, etc. are added to a starch slurry, and amylose clathrate compounds are prepared by heating. For example, a starch slurry composition to which enzymes, etc. have been added and whose pH has been adjusted is heated to an active temperature and maintained in an autoclave, diet stocker, onator, etc., and after denatured to a manageable denaturation range, the enzyme is generally lost. After raising the temperature to an active temperature range (for example, 100° C. or higher), the obtained starch paste solution can be stored and grown into an amylose clathrate compound. Enzymes that can be used include, for example, α-amylase, β-amylase,
These include glucoamylase, pullulanase, R-enzyme, isoamylase, etc., and any of the fine particle production promoters used in the oxidative modification described above can be used as the fine particle production promoter. Starches with a high amylose content, such as corn, wheat,
Rice, potatoes, sweet potatoes, Chinese potatoes, millet,
Starches such as lily, lotus root, wrinkled pea, and tapioca are preferably used, and corn starch, which is particularly rich in free fatty acids, is preferably used. These may be used alone or in combination of two or more. The amylose content of the amylose clathrate compound used as a stilt material is usually 60% or more, and those with an amylose content of 80% or more can be used effectively. Such an amylose clathrate compound is used by being mixed into a paint that forms a microcapsule coating layer of a pressure-sensitive substance and/or a paint coating layer that comes into contact with the microcapsule coating layer. Since the coupling compound has excellent water resistance, solvent resistance, and heat resistance, it can be used without being restricted by the type of liquid carrier and heat treatment conditions during coating formation. Pressure-sensitive copying paper called so-called single color paper, etc., in which the microcapsule coating layer contains microcapsules and a pressure-sensitive substance that reacts with the contents contained in the microcapsules, as well as microcapsules such as ink and fragrance. In cases where the microcapsule coating layer alone exhibits desired pressure-sensitive properties, such as pressure-sensitive substances, the amylose clathrate compound is naturally contained in the microcapsule coating layer. However, in the case of a pressure-sensitive material that has a laminated structure of a material having a microcapsule coating layer and a material having a paint coating layer that comes into contact with the microcapsules, such as ordinary pressure-sensitive copying paper, amylose clathrate compounds are It may be contained in either the capsule coating layer or the paint coating layer that comes into contact with the microcapsules. For example, pressure-sensitive copying paper is produced by a reaction between an electron-donating organic coloring agent and an electron-accepting coloring agent, or by a chelation reaction between a coloring agent and a coloring agent, such as iron alum and pyrite, or ferric sulfate and salicylic acid. The coloring properties are utilized, but in any case, one of the coloring agent and the coloring agent is microencapsulated and applied to one side of the sheet, while the other is left as is as a paint, and then applied to one side of the other sheet. It is used by coating and overlapping the coated surfaces of both sheets. The amylose clathrate compound may be present in either the microcapsule coating layer or the paint coating layer,
Because of its uniform particle size and stable spherical crystal structure, it works very effectively as a stilt material. However, even in the case of pressure-sensitive substances having a laminated structure as described above, it is generally preferable to add an amylose clathrate compound to the microcapsule coating layer, and in particular, it is preferable to add an amylose clathrate compound to the microcapsule coating layer. The use of amylose clathrate compounds is very advantageous since this pasty substance can be used as an adhesive for microcapsules. Although the particle size of the amylose clathrate compound is not particularly limited, it is preferably about 1.5 to 10 times the particle size of the microcapsules contained in the pressure-sensitive substance. Note that any ordinary pressure-sensitive substance can be used as the pressure-sensitive substance of the present invention, and there are no limitations on the microcapsule preparation method or coating method. Next, examples of the present invention will be shown regarding pressure-sensitive copying paper, but the present invention is not limited to these examples. In addition, parts and % in the examples indicate parts by weight and % by weight unless otherwise specified. Production of amylose clathrate compound (1) Disperse unmodified corn starch powder in water,
Make a uniform slurry with a solid content concentration of 35%, and add ammonium persulfate as an oxidizing agent to 100 parts of starch (solid).
0.2 parts (solid) to 100 parts of starch (solid), 0.04 parts of soda carbonate to adjust the pH of the slurry, and 3 parts of calcium stearate as a fine particle generation promoter to 100 parts of starch (solid) to obtain a slurry with a pH of 6. This slurry was subjected to oxidative denaturation at 152°C for 5 minutes in a diet stocker and then stored in a storage tank maintained at 85°C to obtain a starch paste containing amylose clathrate compounds. The average particle size of the amylose clathrate compound was 22μ, and the production rate was 42%.
(In addition, when measuring the particle size distribution of amylose clathrate compounds using a Coulter counter, the particle size was 20μ~
73% were 32μ. ) Production of amylose clathrate compound (2) Amylose clathrate was produced under exactly the same conditions as in production (1), except that 3 parts of polyoxyethylene monolaurate was added to 100 parts of starch (solid) as a fine particle accelerator. A starch paste containing the compound was obtained. The average particle size of the amylose clathrate compound was 23μ, and the production rate was 50%. (In addition, when measuring the particle size distribution of amylose clathrate compounds using a Coulter counter, 74% of the particles had a particle size of 20μ to 32μ.) Production of amylose clathrate compound (3) Unmodified yams as starch powder A mixture of starch and corn starch at a weight ratio of 1:2 was used, except that 3 parts of polyoxyethylene lauryl ether was added as a fine particle generation promoter per 100 parts of starch (solid). A starch paste containing amylose clathrate compound was obtained under exactly the same conditions as in the production of ). The average particle size of the amylose clathrate compound was 21μ, and the production rate was 38%. (In addition, in the particle size distribution measurement of amylose clathrate compound using a Coulter counter, 70% of the particles had a particle size of 20μ to 32μ.) Production of amylose clathrate compound (4) Unmodified corn starch was dispersed in water. , make a uniform slurry with a solid concentration of 20%, add ammonium persulfate as an oxidizing agent to 100 parts of starch (solid)
to 100 parts of starch (solid), 0.04 part of soda carbonate to adjust the slurry pH, and 3 parts of polyoxyethylene lauryl ether as a fine particle generation accelerator to 100 parts of starch (solid) to obtain a slurry with a pH of 6. Ta. This slurry was oxidatively modified in an autoclave and then stored in a storage tank maintained at 85°C to obtain a starch paste containing amylose clathrate compounds. The average particle size of the amylose clathrate compound was 23μ, and the production rate was 35%. (In addition,
Particle size distribution measurement of the amylose clathrate compound using a Coulter counter revealed that 74% of the particles had a particle size of 20μ to 32μ. ) Production of microcapsule dispersion (1) for pressure-sensitive copying paper 30 parts of acid-treated gelatin was added to 270 parts of water, left to stand for 1 hour, then 200 parts of water was added and heated to 60°C to obtain an aqueous gelatin solution. An oil solution prepared by dissolving 4 parts of crystal violet lactone in 100 parts of diisopropylnaphthalene (manufactured by Kureha Chemical Co., Ltd.) was added to the mixture, and the mixture was emulsified and dispersed using a homogenizer so that the average particle size was 6 μm. Then a 10% aqueous solution of gum arabic
After mixing 300 parts into the above emulsion and further adding 200 parts of water, the pH of the system was adjusted to 4.3 with acetic acid, a coacervate film was formed around the oil droplets, and the temperature of the system was then raised to 10°C. After cooling and gelatinizing the coacervate, 25 parts of a 10% formaldehyde aqueous solution was added and allowed to stand for 5 minutes, and the pH of the system was adjusted to 10 by dropping a 10% caustic soda aqueous solution. Cooling was stopped after 3 hours, and gentle stirring was continued for 12 hours at room temperature to obtain a capsule dispersion. Production of microcapsule dispersion (2) for pressure-sensitive copying paper 20 parts of a trimethylolpropane adduct of tolylene diisocyanate (Coronate L manufactured by Nippon Polyurethane Industries, Ltd.) and 3 parts of crystal violet lactone were mixed with diisopropylnaphthalene (Kureha Chemical Industries, Ltd.). KMC oil) dissolved in 100 parts. Add this to polyvinyl alcohol (PVA-117 manufactured by Kuraray)
It was added to 150 parts of a 3% aqueous solution and emulsified using a homomixer so that the average particle size of emulsified oil droplets was 10 μm. The temperature of the obtained emulsified dispersion was raised to 80° C. with stirring, maintained for 3 hours, the isocyanate was allowed to react, and then the temperature was lowered to room temperature to obtain a microcapsule dispersion. Production of microcapsule dispersion liquid (3) for pressure-sensitive copying paper Ethylene and
Maleic anhydride copolymer (manufactured by Monsanto)
300 parts by weight of an aqueous hydrolyzate solution (4%) of EMA-31) was added, 10 parts of urea and 1 part of resorcin were uniformly dissolved, and the pH was adjusted to 3.3 to prepare an aqueous medium for capsule production. Separately, diallylethane (manufactured by Nippon Petrochemical Co., Ltd.)
A hydrophobic solvent solution was prepared by dissolving 3 parts of crystal violet lactone and 1 part of benzoylleucomethylene blue in 100 parts of SAS oil, and this was emulsified and dispersed in the aqueous medium prepared above so that the average particle size was 4μ. . Next, 25 parts of a 37% formaldehyde aqueous solution was added to this dispersion, and the temperature of the system was raised to 75° with gentle heating, held for 3 hours, and then allowed to cool to obtain a capsule dispersion. Production of color developer coating liquid (1) for pressure-sensitive copying paper 65 parts of aluminum hydroxide, 20 parts of zinc oxide, 3,
Zinc 5-di(α-methylbenzylsalicylate and α
- Add 15 parts of a mixture of methylstyrene and styrene copolymer (melt ratio 80/20), 5 parts of polyvinyl alcohol aqueous solution (solid content), and 20 parts of latex (solid content), and apply a color developer coating liquid. Obtained. Manufacture of color developer coating (2) for pressure-sensitive copying paper 100 parts of activated clay, 1 part of sodium hexametaphosphate,
25 parts of latex (solid content) was added to obtain a developer coating solution whose pH was adjusted to 9.5. Example 1 The starch paste obtained in the production of amylose clathrate compound (1) was centrifuged to remove the glue part, and 20 parts (solid content) of the obtained amylose clathrate compound was used as a stilt agent for pressure-sensitive copying paper. In addition to the microcapsule dispersion (1), 20 parts (solid content) of a dissolved oxidized starch aqueous solution was added to prepare a coating liquid. This coating liquid was applied to a base paper of 40 g/m ² to a dry weight of 4.5 g/m ² and dried to obtain a top paper for pressure-sensitive copying paper. This upper paper and the lower pressure-sensitive copying paper obtained by coating and drying the color developer coating liquid (1) for pressure-sensitive copying paper on base paper of 40 g/m ² to a dry weight of 5.5 g/m ² Set the paper with the coated side facing, and check the color density, press dirt,
Abrasion stains were measured for each. The results were as shown in the attached table. Comparative Example 1 Pressure-sensitive copying paper was produced in the same manner as in Example 1, except that 20 parts of wheat starch powder (average particle size 22μ, 49% of particles with a particle size of 20μ to 32μ) was used instead of the amylose clathrate compound. The color density, press stain, and abrasion stain were each measured. The results were as shown in the attached table. Example 2 110 parts of starch paste obtained in the production of amylose clathrate compound (2) (containing 20 parts each of amylose clathrate compound and glue in solid content) was used as a stilt agent to prepare a microcapsule dispersion for pressure-sensitive copying paper (2). ) and used as a coating liquid.
Apply this coating liquid to 40g/ ^m2 base paper with a dry weight of 4.5g/
The coating was applied to a thickness of m ² and dried to obtain a top sheet for pressure-sensitive copying paper. This upper paper and color developer coating liquid for pressure-sensitive copying paper
(1) was applied to a base paper of 40 g/m ² to a dry weight of 5.5 g/m ² and dried, and then the base paper for pressure-sensitive copying paper obtained was set with the coated side facing each other to form a color density. , press stains, and abrasion stains were measured. The results were as shown in the attached table. Comparative example 2 Pulp powder 20 instead of amylose clathrate compound
Pressure-sensitive copying paper was produced in the same manner as in Example 2 except that 20 parts of dissolved oxidized starch aqueous solution (solid content) was used, and its color density, press stain, and abrasion stain were measured. The results were as shown in the attached table. Example 3 The starch paste obtained in the production of amylose clathrate compound (3) was centrifuged to remove the glue portion, and 20 parts (solid content) of the obtained amylose clathrate compound was used as a stilt agent for pressure-sensitive copying paper. In addition to the microcapsule dispersion liquid (3), 20 parts (solid content) of a dissolved oxidized starch aqueous solution was added to prepare a coating liquid. This coating liquid was applied to a base paper of 40 g/m ² to a dry weight of 4.5 g/m ² and dried to obtain a top paper for pressure-sensitive copying paper. Above this, paper and
Apply color developer coating liquid (1) for pressure-sensitive copying paper to base paper of 40 g/m ² to a dry weight of 5.5 g/m ² and dry it. They were set so that they were facing each other, and the color density, press stain, and abrasion stain were measured. The results were as shown in the attached table. Comparative Example 3 In place of amylose clathrate compound, wheat starch powder (average particle size 21μ, 47% with particle size 20μ to 32μ) was used at 20% of amylose clathrate compound.
Pressure-sensitive copying paper was produced in the same manner as in Example 3, except that the sample was used, and its color density, press stain, and abrasion stain were measured. The results were as shown in the attached table. Example 4 The starch paste obtained in the production of amylose clathrate compound (4) was centrifuged to remove the glue part, and 20 parts (solid content) of the obtained amylose clathrate compound was used as a stilt agent for pressure-sensitive copying paper. In addition to the microcapsule dispersion liquid (2), 20 parts (solid content) of a dissolved oxide starch aqueous solution was added to prepare a coating liquid. This coating liquid was applied to a base paper of 40 g/m ² to a dry weight of 4.5 g/m ² and dried to obtain a top paper for pressure-sensitive copying paper. This upper paper and the lower pressure-sensitive copying paper obtained by coating and drying the color developer coating liquid (2) for pressure-sensitive copying paper on base paper of 40 g/m ² to a dry weight of 5.5 g/m ² Set the paper with the coated side facing, and check the color density, press dirt,
Abrasion stains were measured for each. The results were as shown in the attached table. Comparative example 4 Pulp powder 20 instead of amylose clathrate compound
Pressure-sensitive copying paper was produced in the same manner as in Example 4, except that the sample was used, and its color density, press stain, and abrasion stain were measured. The results were as shown in the attached table. Example 5 20 parts (solid content) of a dissolved oxidized starch aqueous solution was added to the microcapsule dispersion liquid (1) for pressure-sensitive copying paper to prepare a coating liquid. Apply this coating liquid to 40g/ ^m2 base paper with a dry weight of 4.5
g/m ² and dried to obtain a top sheet for pressure-sensitive copying paper. The above paper and the starch paste obtained in the production of amylose clathrate compound (1) were centrifuged to remove the glue, and 20 parts (solid content) of the obtained amylose clathrate compound was collected under a microscope for pressure-sensitive copying paper. Color coating liquid (1)
In addition, the developer coating solution obtained was applied to base paper of 40 g/m ² to a dry weight of 5.5 g/m ² and dried, and the coated side was placed opposite to the bottom paper for pressure-sensitive copying paper obtained. The sample was set in this way, and the color density, press stain, and abrasion stain were measured. The results were as shown in the attached table. Comparative Example 5 In place of amylose clathrate compound, wheat starch powder (average particle size 22 μ, 49% of particle size 20 μ to 32 μ) was used at 20 μm.
Pressure-sensitive copying paper was produced in the same manner as in Example 5, except that the same amount of paper was used, and its color density, press stain, and abrasion stain were measured. The results were as shown in the attached table. Example 6 The starch paste obtained in the production of amylose clathrate compound (1) was centrifuged to remove the glue part, and 20 parts (solid content) of the obtained amylose clathrate compound was used as a stilt agent for pressure-sensitive copying paper. In addition to the microcapsule dispersion (2), 5 parts (solid content) of a dissolved oxidized starch aqueous solution was added to prepare a coating liquid. This coating liquid was applied to a base paper of 40 g/m ² to a dry weight of 4 g/m ² and dried. Next, a color developer coating liquid prepared from the color developer coating liquid (2) for pressure-sensitive copying paper was applied onto the surface coated with the microcapsules at a dry weight of 5 g/m ² and dried to form a single pressure-sensitive recording paper. The color density, press stain, and abrasion stain were measured. The results were as shown in the attached table. Comparative Example 6 Instead of amylose clathrate compound, wheat starch powder (average particle size 22μ, 49% with particle size 20μ to 32μ)
A pressure-sensitive recording paper was produced in the same manner as in Example 6, except that 20 copies of the paper were used, and its color density, press stain, and abrasion stain were measured. The results were as shown in the attached table.

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Claims (1)

[Scope of Claims] 1. A pressure-sensitive substance having a pressure-sensitive microcapsule coating layer, wherein a granular amylose clathrate is contained in the microcapsule coating layer and/or a paint coating layer that comes into contact with the microcapsule coating layer. A pressure-sensitive substance characterized by being dispersed as a stilt substance. 2. The pressure-sensitive material according to claim 1, wherein the amylose clathrate compound is present together with a pasty substance that is a by-product during its production. 3 The amylose clathrate compound contains amylose at 80
3. The pressure-sensitive substance according to claim 1 or 2, wherein the pressure-sensitive substance is contained in a proportion of % or more. 4. According to any one of claims 1 to 3, wherein the amylose clathrate compound is formed by heating a starch slurry containing an oxidizing agent and a fine particle formation promoter. Pressure-sensitive substances listed. 5. The pressure-sensitive material according to claim 4, wherein the oxidizing agent is a peroxide. 6. The amylose clathrate compound according to any one of claims 1 to 3, wherein the amylose clathrate compound is formed by heating a starch slurry containing an enzyme and a fine particle production promoter. Pressure sensitive substances. 7 The fine particle formation promoter is selected from ethers of alcohols having 1 to 22 carbon atoms, esters of fatty acids having 1 to 22 carbon atoms, sulfuric ester salts of alcohols having 1 to 22 carbon atoms, fatty acids having 1 to 22 carbon atoms, and salts thereof. The pressure-sensitive material according to any one of claims 4 to 6, characterized in that the material is selected from the group consisting of: 8. The pressure-sensitive substance according to any one of claims 1 to 7, wherein the particle size of the amylose clathrate compound is 1.5 to 10 times the particle size of the microcapsule. 9. The pressure-sensitive material according to any one of claims 1 to 8, wherein the microcapsule coating layer alone exhibits desired pressure-sensitive properties. 10. The pressure-sensitive material according to claim 9, wherein the microcapsule coating layer contains a substance that reacts with microcapsules and the contents contained in the microcapsules. 11. Any one of claims 1 to 8, wherein the pressure-sensitive substance has a laminated structure of a material having a microcapsule coating layer and a material having a paint coating layer that comes into contact with the microcapsules. A pressure-sensitive substance described in Crab. 12. The pressure-sensitive material according to any one of claims 1 to 11, wherein the pressure-sensitive material is pressure-sensitive copy paper.