JPH08169178A - Recording material - Google Patents

Abstract

PURPOSE: To provide a recording material which uses vegetable oil which has no offensive odor and is biologically degradable as a solvent for dissolving an electron donating color coupler which develops color by contact with an electron accepting developer and can easily obtain a colored image which has high color density and desired hue and is almost free from color stains. CONSTITUTION: In a recording material containing micro-capsules containing an electron donating color coupler dissolved in a solvent and an electron accepting developer, the color coupler is crystal violet lactone, and the solvent is a mixture of fatty acid triglyceride in which at least one fatty acid has a hydroxyl group and vegetable oil with an oleic acid residue content of 10-60wt.%.

Description

Detailed Description of the Invention

[0001]

The present invention has almost no odor,
The present invention relates to a sheet-shaped recording material having high biodegradability and capable of developing color at a high density.

[0002]

2. Description of the Related Art Microcapsules containing an electron-donating color former (hereinafter sometimes referred to as "color former") dissolved in a solvent and an electron-accepting developer (hereinafter referred to as "color former") The recording material utilizing the fact that a color-developed image is formed by the reaction between a color-developing agent and a color-developing agent has been known for a long time and is widely used.

Such recording materials are roughly classified into pressure sensitive recording materials and heat sensitive recording materials. The pressure-sensitive recording material is one in which a microcapsule containing a color-developing agent is destroyed by applying a pressure to this to form a color-developed image by reacting the color-developing agent with the color-developing agent. Coloring agent layer comprising microcapsules containing (hereinafter, "coloring agent layer"
And a developer layer containing a developer (hereinafter,
And a "color developer layer") are formed on the surfaces of separate supports or different surfaces of the same support, and the carbon-free paper is used by bringing the color developer layer and the developer layer into contact with each other. Type recording material, a so-called self-coloring type pressure-sensitive recording material (or press-type paper, self-developing) provided with a self-coloring layer containing a microcapsule containing a color-forming agent and a developer on the same surface of a support. There is something called a "contained paper".

In a carbonless paper type recording material, a color former layer is formed on one side of a support (generally paper) to form an upper sheet, and a color former layer is formed on one side of the support and on the opposite side. It is used by forming a developer layer to form a middle paper, forming a developer layer on one side of a support to form a lower paper, and contacting the color developer layer with the developer layer.

In addition, in the self-coloring type pressure-sensitive recording material, when pressure is applied to the surface on which the self-coloring layer is provided, the microcapsules are destroyed and the color-developing agent reacts with the color-developing agent to develop a color on the self-coloring layer. Since an image is formed, plain paper is placed on the self-coloring layer of the self-coloring type pressure-sensitive recording material, and an image such as letters is recorded on the plain paper with a writing instrument, type, etc. When forming a color image on the color-developing layer, OCR printing is performed when a color-developed image is formed by printing directly on the self-color-developing layer of the self-color-developing pressure-sensitive recording material without using an ink ribbon. It is used in some cases. Furthermore, when making multiple copies, a self-coloring type pressure-sensitive recording material in which a self-coloring layer is provided on one side of the support and a color-developing layer is formed on the opposite side is used to form a color on one side of the support. It may be used in combination with a medium sheet having a developer layer and a developer layer on the opposite side thereof or a lower sheet having a developer layer on one surface of a support. The self-coloring layer of the self-coloring type pressure-sensitive recording material includes a two-layer type in which a color-developing layer containing microcapsules containing a color-developing agent and a color-developing layer containing a color-developing agent are laminated, and in the same layer. There is a single-layer type including a color developer and a microcapsule containing a color developer.

On the other hand, a heat-sensitive recording material containing such microcapsules is disclosed in, for example, JP-A-63-2656.
No. 82 and JP-A-1-105782, there is a heat-sensitive recording material in which a heat-sensitive layer containing microcapsules containing a color former and a color developer is formed on a support. The heat-sensitive recording material containing the microcapsules is
It has an advantage that it can be designed for HP or can be designed as a multicolor heat-sensitive recording material.

The microcapsules contained in the recording material as described above contain a color former dissolved in a solvent. As the solvent, a substance capable of dissolving the color former used is used, and generally, kerosene, paraffin, naphthene oil, alkylated biphenyl, alkylated terphenyl,
Chlorinated paraffins, alkylated naphthalenes, diarylalkanes, phthalates and the like are used. However, many of these solvents generally have a bad or unpleasant odor, and also include an ecologically unfavorable one that may cause adverse effects on the human body during environmental pollution or during manufacture and use.

JP-A-50-90409 discloses that when a pressure-sensitive recording paper is manufactured by providing a microcapsule layer containing a color-forming agent solution on a support, the color-forming agent is added to 10
Disclosed is a method for producing a pressure-sensitive recording paper, which comprises dissolving in animal or vegetable oil heated to 5 to 260 ° C.

The animal oils and vegetable oils used in the above method are natural products and can be used for foods, have no offensive or unpleasant odor, are ecologically safe substances, and are relatively inexpensive. It is easily available and is a preferable solvent as the solvent of the color former solution in the microcapsules.

However, animal oils and vegetable oils have a small dissolving power for commonly used color formers, it is difficult to increase the concentration of the color former in the color former solution, and there is a problem that the color density of the recording material is low. . In the above method, the color former is dissolved in the animal oil or the vegetable oil at a high temperature such as 105 to 260 ° C. when the color developer solution is prepared, but when the animal oil or the vegetable oil is heated to a high temperature, it is easily oxidized and deteriorated. However, there is also a problem that an unpleasant odor or a bad odor may be generated. Further, depending on the coloring agent, the coloring property may be inhibited (desensitized).

The applicant of the present invention uses a glyceride such as the above vegetable oil and a specific fluoran compound or a specific indolyl phthalide or indolyl azaphthalide, which is soluble in the vegetable oil, as a recording material having improved color development using the above vegetable oil. A recording material composed of encapsulated microcapsules has already been filed (Japanese Patent Application No. 5-196132 and Japanese Patent Application No. 5196132).
187227).

However, it is necessary to obtain a color developing agent other than the above-mentioned color developing agents that is difficult to dissolve in vegetable oil so as to obtain a specific hue or to adjust the hue of the color developing, and to obtain it. It is of course also desirable to use as much of the easy color former as possible. For example, when crystal violet lactone, which is widely used as a color-developing agent showing a blue color, is used, it cannot be sufficiently dissolved even if the above-mentioned vegetable oil is used as a solvent. And, when such a coloring agent solution in an insufficiently dissolved state is microencapsulated, the capsule wall forming material that does not contribute to the formation of the capsule wall remains as a residue, which is disadvantageous in manufacturing, and The recording material using the microcapsules thus obtained has problems that the color density is lowered and stains are likely to occur during color development.

[0013]

DISCLOSURE OF THE INVENTION An object of the present invention is as a solvent for dissolving an electron-donating color developing agent that develops a color upon contact with an electron-accepting developer, a vegetable oil having no bad odor and having biodegradability. It is an object of the present invention to provide a recording material which is easy to obtain a color image having a desired hue, which has a high color density and almost no color stain.

[0014]

The present invention is a recording material containing microcapsules containing an electron-donating color developing agent dissolved in a solvent, and an electron-accepting color developing agent. The agent is crystal violet lactone, and the solvent is a mixture of a triglyceride of a fatty acid in which at least one of the constituent fatty acids has a hydroxyl group, and a vegetable oil having a fatty acid residue composition having an oleic acid residue content of 10 to 60% by weight. The recording material is characterized in that

The preferred embodiments of the present invention are as follows.

1) The mixing ratio of the above triglyceride and vegetable oil is in the range of 8: 2 to 1: 9 by weight (preferably 7: 3).
~ 2: 8) above recording material. 2) The recording material as described above, wherein the triglyceride is castor oil. 3) The recording material, wherein the electron-donating color former is dissolved in a solvent in an amount of 3 to 12% by weight. 4) The recording material as described above, wherein the walls of the microcapsules are polyurethane urea. 5) The recording material as described above, wherein the electron-donating color former further contains at least one selected from the group consisting of benzoyl leuco methylene blue, fluorane compounds, indolyl phthalide compounds and indolyl azaphthalide compounds. 6) The recording material is a pressure-sensitive recording material.

The form of the recording material of the present invention is not particularly limited as long as it contains the above-mentioned electron-donating color former and developer. That is, the recording material of the present invention is a carbon-free paper-type pressure-sensitive recording material in which the above-mentioned color former layer and developer layer are formed on the surfaces of separate supports or different surfaces of the support. A self-coloring type pressure-sensitive recording material provided with a microcapsule containing a color former and a self-coloring layer containing a developer on the same surface of the body, and a microcapsule containing the color former and a developer It may be in any form of a heat-sensitive recording material having a heat-sensitive layer formed on a support. As described above, the recording material of the present invention is characterized in that the color-forming agent contained in the microcapsules is crystal violet lactone, and the solvent in which the color-forming agent is dissolved is limited to a specific mixture of glyceride and vegetable oil. It is a thing.
Hereinafter, mainly the carbonless paper type pressure-sensitive recording material will be described in detail. It will be easily understood by those skilled in the art that similar effects can be obtained with other types of recording materials.

The solvent used in the present invention to dissolve the color former is a triglyceride in which at least one of the constituent fatty acids has a hydroxyl group, and a fatty acid residue having an oleic acid residue content of 10 to 60% by weight. It is a vegetable oil having a basic composition. As the fatty acid having a hydroxyl group of triglyceride in which at least one of the constituent fatty acids has a hydroxyl group, ricinoleic acid, ricinostearic acid, 2,10-dioxytridecanoic acid, 3,11-dioxymyristic acid, 2-oxyvaleric acid, 2-oxycaprylic acid, 2-oxylauric acid, 2-oxymyristic acid, 2-oxypalmitic acid (lanoparmic acid), 2-
Oxystearic acid, 2-oxypetroselinic acid, 2-
Oxy-7-octadecenoic acid, 2-oxyoleic acid,
2-oxyelaidic acid, 2-oxy-10-octadecenoic acid, 2-oxylinoleic acid, 2-oxylinolenic acid, 2-oxyerucic acid, 3-oxycaprylic acid, 3-
Oxymyristic acid, 3-oxypalmitic acid, 3-oxystearic acid, 3-oxypeteroseric acid, 3-oxy-7-octadecenoic acid, 3-oxyoleic acid, 3
-Oxyelaidic acid, 3-oxy-10-octadecenoic acid, 3-oxylinoleic acid, 3-oxylinolenic acid,
3-oxyerucic acid, 4-oxylinoleic acid, 5-oxyoleic acid, 6-oxystearic acid, 7-oxylinoleic acid, 8-oxystearic acid, 9-oxystearic acid, 10-oxystearic acid, 11-oxy Stearic acid, 12-oxylauric acid (sabinic acid), 1
3-oxytridecanoic acid, 14-oxymyristic acid,
15-oxypentadecanoic acid, 16-oxypalmitic acid (juniperic acid), 18-oxystearic acid, 1
8-oxyoleic acid, 18-oxylinoleic acid, 18
-Oxylinolenic acid, ricinoleic acid, 2,3-dioxylauric acid, 2,3-dioxystearic acid, 2,3
-Dioxyoleic acid, 2,3-dioxylinoleic acid,
7,8-Dioxyoleic acid, 9,10-dioxyoleic acid, 10,11-dioxyoleic acid, 11,12
Mention may be made of dioxyoleic acid, 12,13-dioxyoleic acid and 9-oxy-10-methoxystearic acid. Ricinoleic acid, juniperic acid, sabinic acid, lanopalmic acid, ricinoelaidic acid and ricinostearol acid are preferred.

Among the constituent fatty acids, fatty acids other than the above-mentioned fatty acids having a hydroxyl group include acetic acid, propionic acid, butyric acid, caprylic acid, lauric acid, myristic acid, palmitic acid,
Stearic acid, stearic acid, petroselinic acid, 7-
Octadecenoic acid, oleic acid, elaidic acid, linoleic acid, linolenic acid, arachidic acid, arachidonic acid, behenic acid, brassic acid, erucic acid, docosahexaenoic acid, ricinoleic acid, 2-ketopropionic acid, 2-ketrauric acid, 2-keto Myristic acid, 2-ketostearic acid, 2
Mention may be made of ketooleic acid, 2-ketolinoleic acid, 3-ketooleic acid, α-licanoic acid, 4-keto-5-methoxystearic acid and 9-keto-10-methoxystearic acid.

Examples of the triglyceride of fatty acid having a hydroxyl group include triglyceride having one fatty acid having a hydroxyl group, triglyceride having two fatty acids or triglyceride having three fatty acids, or a mixture thereof. As such triglyceride, any oil such as natural vegetable oil or synthetic oil may be used.
Examples of natural vegetable oils include Isano oil, ergot oil and castor oil. Castor oil is particularly preferable.

In the present invention, a vegetable oil having a fatty acid residue composition with an oleic acid residue content of 10 to 60% by weight is used together with the above-mentioned triglyceride having a hydroxyl group. Examples of the vegetable oil include soybean oil (oleic acid residue content (OA) in fatty acid residue composition = 20 to 35% by weight),
Corn oil (OA = 25-45% by weight), rapeseed oil (OA = 10-35% by weight), cottonseed oil (OA = 15-3)
0% by weight), sesame oil (OA = 35 to 46% by weight), peanut oil (OA = 35 to 60% by weight), sunflower oil (OA =
15 to 35% by weight) and the like. Among them, soybean oil, corn oil, rapeseed oil, cottonseed oil, etc.
It is preferable in that the solubility of the color-forming agent used (the ability to dissolve the color-developing agent (solvent power)) is high, the color-developing ability when reacted with the color-developing agent is high, and that the color-forming agent is easily available industrially. These vegetable oils may be used alone or in combination. The oleic acid content in the fatty acid residue composition is 60% by weight, such as olive oil (OA = 70 to 85% by weight).
Larger vegetable oils have poor solubility of the color former and are not preferred.

The mixing ratio of the triglyceride having a hydroxyl group to the vegetable oil is preferably in the range of 8: 2 to 1: 9 by weight (triglyceride: vegetable oil), and 7: 3 to.
2: 8 is more preferable, and 6: 4 to 3: 7 is particularly preferable. When the triglyceride having a hydroxyl group exceeds 80% by weight, the color-developing agent is sufficiently soluble but the desensitizing effect is remarkable, which is not preferable. On the other hand, if it is less than 10% by weight, the problem of desensitizing action does not occur at all, but it is not preferable because the solubility of the color former is not sufficient.

In the present invention, the solvent conventionally used together with the above-mentioned triglyceride and vegetable oil as a solvent is added in such an amount that does not give an unpleasant odor to the recording medium (generally 30% by weight of the total of triglyceride and vegetable oil). The following amount)
May be used in.

The color-developing agent used in the present invention is a color-developing agent containing crystal violet lactone, and any known color-developing agent other than crystal violet lactone can be used as long as it is soluble in a solvent containing the above-mentioned triglyceride having a hydroxyl group and vegetable oil as a main component. Color formers can also be used. As the color former, triphenylmethanephthalide compounds other than crystal violet lactone, fluorane compounds,
Phenothiazine compounds, indolyl phthalide compounds, indolyl azaphthalide compounds, leuco auramine compounds, rhodamine lactam compounds, triphenylmethane compounds, triazene compounds, spiropyran compounds Can be mentioned. Among these, benzoyl leuco methylene blue, fluoran compounds, indolyl phthalide compounds and indolyl azaphthalide compounds are preferable. As described above, the solvent containing a triglyceride having a hydroxyl group and a vegetable oil as the main components of the present invention is suitable for dissolving crystal violet lactone. Further, the amount of crystal violet lactone used in the present invention is 50% of the total amount of the color former.
It is preferable that the content is at least wt. Especially 60 to 1
It is preferable that the amount is 00 weight.

In producing the microcapsules containing the color former, the color former is dissolved in a mixture of the triglyceride having a hydroxyl group and the vegetable oil as described above to prepare a color former solution. The color former is dissolved in the vegetable oil. The temperature at that time is preferably 80 to 130 ° C. At a temperature lower than the above range, the color former is difficult to dissolve in the vegetable oil, and at a temperature higher than the above range, the vegetable oil may deteriorate. Also,
The concentration of the color former in the color former solution is 3 with respect to vegetable oil.
It is preferably from 12 to 12% by weight, particularly from 4 to 10% by weight.

The microcapsules containing the color former can be produced by any method known per se, for example, interfacial polymerization method, internal polymerization method, phase separation method, external polymerization method, coacervation method and the like. it can.

The wall material of the microcapsules is not particularly limited as long as it is a water-insoluble or oil-insoluble polymer which is conventionally used as a wall material of the color-forming agent-containing microcapsules of the pressure-sensitive recording material. , A polyurethane urea wall, a melamine / formaldehyde wall, a gelatin wall and the like. The wall material of the microcapsules is particularly preferably a polyurethane urea resin because of its high resistance to thermal fog.

The microcapsules having a polyurethane urea wall containing the color former as described above are emulsified and dispersed in a hydrophilic liquid by dissolving a solution of a polyvalent isocyanate, a polyvalent hydroxy compound and the electron donating color former in the vegetable oil. Then, a polyvalent amine is added to the emulsified dispersion, and the hydrophobic droplets can be prepared by coating with a polyurethane urea film. The dispersion liquid containing the microcapsules thus obtained can be used as a coating liquid for forming a color former layer.

As the polyvalent isocyanate used in the present invention, hydrogenated xylylene diisocyanate (generally called hydrogenated XDI) isocyanurate, isophorone diisocyanate (generally called IPDI) isocyanurate, 4,4 '. -Diphenylmethane diisocyanate, an adduct of hexamethylene diisocyanate and trimethylolpropane, biuret of hexamethylene diisocyanate, isocyanurate of hexamethylene diisocyanate, polymethylene polyphenyl isocyanate, carbodiimide-modified diphenylmethane diisocyanate, tolylene diisocyanate and trimethylolpropane and Adduct of xylylene diisocyanate with trimethylol propane, Cyanurates, hydrogenated xylylene diisocyanate adducts with trimethylol propane, isophorone diisocyanate adducts with trimethylol propane, xylylene diisocyanate biuret and tris- (p-isocyanatophenyl) thiophosphite Etc. can be mentioned.

Of these, hydrogenated xylylene diisocyanate isocyanurates and isophorone diisocyanate isocyanurates are preferable because of their excellent solubility in vegetable oils. It is preferable to use a mixture of these two kinds of polyvalent isocyanate and aromatic polyvalent isocyanate, and the mixing ratio thereof is 8: 2 to 2: 8 by weight.
Is preferable (2 types: aromatic), and in particular, 7: 3 to 3:
A range of 7 is preferred.

The compound capable of polymerizing with a polyvalent isocyanate is
Water, a polyvalent hydroxy compound and / or a polyvalent amine. Specific examples of the above-mentioned polyhydric hydroxy compounds include aliphatic or aromatic polyhydric alcohols, hydroxypolyesters, hydroxypolyalkylene ethers, alkylene oxide adducts of polyvalent amines, and the like.

The above polyvalent amine compound is a compound having two or more --NH-- groups or --NH ₂ groups in the molecule and soluble in a hydrophilic liquid. Specific examples of the polyvalent amine compound include ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, 1,3-propylenediamine, hexamethylenediamine, phenylenediamine, diaminonaphthalene,
Examples include xylylenediamine and the like.

The dispersion liquid of the microcapsules prepared as described above is used as it is as a coating liquid for forming a color former layer, or a binder, a capsule protecting agent and the like are further added to this microcapsule dispersion liquid to form a color former layer. A coating liquid for formation is prepared, coated on a support by a method known per se, and dried to form a color former layer of a carbonless paper pressure-sensitive recording material. As the binder, a water-soluble binder, a latex binder or the like can be used, and as the capsule protecting agent, cellulose powder, starch particles, talc or the like can be used.

As the support, any support conventionally used as a support for a pressure-sensitive recording material or a heat-sensitive recording material, for example, paper from wood pulp, paper surface-treated with this paper, or plastics material is used. Synthetic paper, plastics film, etc. from can be used.

The final coating amount of the color former to be coated on the support is
0.05-0.30 g / m ² , preferably 0.08-
0.20 g / m ² is suitable.

The color developer contained in the color developing layer of the carbonless paper type pressure-sensitive recording material of the present invention includes acidic clay, activated clay, attapulgite, zeolite, bentonite, clay substances such as kaolin, and aromatic carvone. Acid (eg,
Examples thereof include metal salts of salicylic acid derivatives) and phenol formaldehyde resins. From the viewpoint of ecology, the developer is preferably a clay substance.

The coating liquid for forming the developer layer is
It can be prepared by a method known per se.For example, as a binder, styrene-butadiene copolymer latex, vinyl acetate latex, acrylic ester latex, polyvinyl alcohol, polyacrylic acid, It may contain synthetic or natural polymer substances such as maleic anhydride-styrene-copolymer, starch, casein, gum arabic, gelatin, carboxymethylcellulose, methylcellulose and the like.
The developer layer can be formed on the support as described above by a method known per se.

The final coating amount of the color developer applied to the support is
^{0.1g / m 2 ~4.0g / m 2} , preferably 0.2g
/ M ^{2 to} 3.0 g / m ² is suitable.

The carbonless paper pressure-sensitive recording material of the present invention has the same constitution as that of the conventionally known carbonless pressure-sensitive recording material except that the above-mentioned specific vegetable oil is used as a solvent for dissolving the color former. It can be manufactured in the same manner.

The recording material of the present invention has been described above with respect to the carbonless paper type pressure sensitive recording material. However, the above-mentioned self-coloring type pressure sensitive recording material and heat sensitive recording material also have specific microcapsules as described above. Other than the use, each can be configured and manufactured in the same manner as a conventionally known recording material.

[0041]

EXAMPLES Next, the present invention will be described in more detail with reference to Examples and Comparative Examples.

[Example 1] [Preparation of coating solution for forming color former layer] As a color former, 9.0 g of crystal violet lactone and 50 g of rapeseed oil were used.
And 50 g of castor oil were heated to 120 ° C. and dissolved. 6.0 g of an isocyanurate body of hydrogenated XDI (manufactured by Takeda Pharmaceutical Co., Ltd., trade name "Takenate D-127N", 75 wt% ethyl acetate solution) as a polyvalent isocyanate was added to the obtained oily liquid, and carbodiimide-modified diphenylmethane diisocyanate. (Mitsui Toatsu Chemical Co., Ltd., trade name "Cosmonate LK", solid content 100%) 6.0 g dissolved in ethyl acetate 30 g solution and ethylenediamine butylene oxide adduct (number of moles of butylene oxide added to ethylenediamine) 16.8 mol, molecular weight 1
267) 3.0 g was dissolved to prepare a primary solution.

Next, 10 g of polyvinyl alcohol and 5 g of carboxymethyl cellulose were dissolved in 140 g of water by heating in a stainless steel container to prepare a secondary solution. While vigorously stirring the secondary solution, the primary solution was poured into the secondary solution to form an oil-in-water emulsion. When the size of the oil droplet reached 6.0 μm, the stirring was weakened, and then 100 mL of water at 20 ° C. was added to this emulsion.
g and tetraethylenepentamine 2.0 g were added,
The temperature of the system is gradually raised to 80 ° C, and at this temperature 9
The capsule dispersion was prepared by maintaining for 0 minutes.

To the thus obtained capsule liquid, 80 g of a 15% aqueous solution of polyvinyl alcohol, 15 g of carboxy-modified SBR latex as a solid content and 40 g of starch particles (average particle size 15 μm) were added. Next, water was added to adjust the solid content concentration to 20% by weight to prepare a color developer layer-forming coating liquid (microcapsule dispersion liquid) containing microcapsules containing the color developer.

[Preparation of Coloring Agent Sheet] On one side of a base paper of 50 g / m ² , 5.0 g / m ² of the above coating solution for forming a coloring agent layer was formed.
The solid content of ² was applied using an air knife coater and dried to prepare a color former sheet.
This color former sheet had very little odor.

[Preparation of color developer sheet] 20 to 100 g of water
5 g of a weight% sodium hydroxide aqueous solution and 1 g of 10 wt% sodium hexametaphosphate were added. 2 g of magnesium oxide and 60 g of activated clay (manufactured by Mizusawa Chemical Co., Ltd., trade name "Silton F-242") as a developer in the obtained solution.
Was added and dispersed using a homogenizer (AM-7, manufactured by Nippon Seiki Co., Ltd.) at 10,000 rpm for 5 minutes to obtain a developer dispersion. An aqueous starch solution was prepared by dissolving 5 g of wheat flour in 100 g of a 1 wt% sodium hydroxide aqueous solution. 35 g of an aqueous starch solution and 15 g of SBR latex (solid content) were added to 100 g of the developer dispersion described above, and water was further added to adjust the solid content concentration to 20% by weight. Was prepared. 5.0 g / m ² of the coating liquid for forming the developer layer on one side of the base paper of 50 g / m ^2.
It was applied using a bar coater so that the solid content of ² was applied and dried to prepare a developer sheet.

Comparative Example 1 [Preparation of Coloring Agent Sheet] Instead of 50 g of rapeseed oil and 50 g of castor oil used in the preparation of the coating solution for forming the coloring agent layer in Example 1, 100 g of rapeseed oil were used. A color former sheet was produced in the same manner as in Example 1 except that the coating liquid for forming a color former was prepared in the same manner as in Example 1 except that it was used. Further, a developer sheet was prepared in the same manner as in Example 1.

Example 2 [Preparation of Coloring Agent Sheet] 50 g of corn oil was used instead of 50 g of rapeseed oil and 50 g of castor oil used in the preparation of the coating solution for forming the coloring agent layer in Example 1. A color former sheet was prepared in the same manner as in Example 1, except that the coating liquid for forming a color former was prepared in the same manner as in Example 1 except that 50 g of castor oil was used. Further, a developer sheet was prepared in the same manner as in Example 1.

Comparative Example 2 [Preparation of Coloring Agent Sheet] 100 g of corn oil was used instead of 50 g of corn oil and 50 g of castor oil used in the preparation of the coating solution for forming the coloring agent layer in Example 2. A color-forming agent sheet was prepared in the same manner as in Example 2 except that the coating liquid for forming a color-forming agent was prepared in the same manner as in Example 2 except that it was used. Further, a developer sheet was prepared in the same manner as in Example 1.

Example 3 [Preparation of Coloring Agent Sheet] 50 g of soybean oil and 50 g of soybean oil were used instead of 50 g of rapeseed oil and 50 g of castor oil used in the preparation of the coating solution for forming the coloring agent layer in Example 1. A color former sheet was prepared in the same manner as in Example 1, except that the coating liquid for forming a color former was prepared in the same manner as in Example 1 except that 50 g of castor oil was used. Further, a developer sheet was prepared in the same manner as in Example 1.

Comparative Example 3 [Preparation of Coloring Agent Sheet] 100 g of soybean oil was used instead of 50 g of soybean oil and 50 g of castor oil used in the preparation of the coating liquid for forming the coloring agent layer in Example 3. A color forming agent sheet was prepared in the same manner as in Example 3 except that the coating liquid for forming a color forming agent layer prepared in the same manner as in Example 3 was used. Further, a developer sheet was prepared in the same manner as in Example 1.

Example 4 [Preparation of Coloring Agent Sheet] 50 g of soybean oil was used instead of 50 g of rapeseed oil and 50 g of castor oil used in the preparation of the coating solution for forming the coloring agent layer in Example 1. 1-ricino leo
Using the coating liquid for forming the colorant layer prepared in the same manner as in Example 1 except that 50 g of 2,3-diolein was used,
A color former sheet was prepared in the same manner as in Example 1. Further, a developer sheet was prepared in the same manner as in Example 1.

Comparative Example 4 [Preparation of Coloring Agent Sheet] 100 g of castor oil was used in place of 50 g of rapeseed oil and 50 g of castor oil used in the preparation of the coating liquid for forming the coloring agent layer in Example 1. A color former sheet was prepared in the same manner as in Example 1 except that the coating liquid for forming a color former was prepared in the same manner as in Example 1 except for the above. Further, a developer sheet was prepared in the same manner as in Example 1.

(1) The following tests were conducted on the color former solutions and the color developer layer forming coating solutions (microcapsule dispersions) obtained in the above Examples and Comparative Examples. a) Stability of color former solution The color former solution obtained by heating and dissolving at 120 ° C is gradually added to 5
After cooling to 0 ° C., the presence or absence of precipitate was visually observed. b) Residue of microcapsule dispersion liquid 1000 g of the obtained microcapsule dispersion liquid was filtered through a 250-mesh sieve, and the solid matter remaining on the sieve was dried at 100 ° C. for 1 hour, and the weight thereof was measured.

(2) The following tests were carried out using the color former sheet and the color developer sheet obtained in the above Examples and Comparative Examples. c) Coloring density test The color-developing sheet and the color-developing sheet prepared as described above are overlaid, and an electronic typewriter (IBM 6747 type) is used to continuously print by printing the lowercase letter m of the alphabet to develop color on the color-developing layer. Let The obtained color image was allowed to stand at room temperature for 24 hours, and then the density (D) of the color developer in the developer layer was measured using a Macbeth reflection densitometer. d) Color stain on the color developer sheet The color developer layer of the color developer sheet and the developer layer of the developer sheet are superposed so as to be in contact with each other, and a load of 500 g is applied thereonto at 40 ° C. and 90% RH. It was left under the conditions for 3 days. The density (D) of the color-developing agent in the developer layer after standing was measured using a Macbeth reflection densitometer. The results are shown in Table 1.

[0056]

[Table 1] Table 1 ──────────────────────────────────── a) Coloring agent b) Capsule c ) Color density d) Color stains Solution stability Dispersion residue (mg) ─────────────────────────────────── Example 1 No Precipitation 10.5 0.49 0.11 Comparative Example 1 Precipitation 407.8 0.50 0.27 ──────────────────── ──────────────── Example 2 No Precipitation 12.3 0.49 0.12 Comparative Example 2 Precipitation 405.2 0.50 0.25 ────── ────────────────────────────── Example 3 No Precipitation 9.8 0.49 0.11 Comparative Example 3 Precipitation 396 .5 0.51 0.25 ─────────── ───────────────────────── Example 4 No precipitation 22.1 0.50 0.12 ──────────── ───────────────────────── Comparative Example 4 Precipitation 10.2 0.43 0.28 ──────────── ─────────────────────────

The color former solutions used to prepare the recording materials obtained in the examples were excellent in stability and their capsule dispersions had little residue. Further, when the color developer sheet obtained by using these coating solutions is used as a recording material in combination with the developer sheet, it is possible to form a color-developed image with a high color density on the developer sheet, and There were few colored stains. On the other hand, in Comparative Examples 1 to 3 in which the triglyceride having a hydroxyl group was not used as the solvent for dissolving the color former, the stability of the color former solution was poor and the residue of the capsule dispersion was large. When used in combination with the color developer sheet, there was much color stain. In Comparative Example 4 in which only triglyceride having a hydroxyl group was used, the stability of the color developing agent solution was excellent and the residue of the capsule dispersion was small, but the desensitizing effect was strong and a color developed image having a high color density was formed on the developer sheet. It was not possible, and there were many colored stains.

[0058]

INDUSTRIAL APPLICABILITY The recording material of the present invention uses a color-developing agent such as crystal violet lactone which has no unpleasant odor or bad odor, has a high ecological safety and is generally difficult to dissolve in vegetable oil. In addition, it is possible to form a color image having a high color density, and a markedly excellent effect that color stain is unlikely to occur at that time is exhibited.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location B41M 5/30 5/28 B41M 5/18 101 C 103 110 112

Claims (3)

[Claims] 1. A recording material comprising microcapsules containing an electron-donating color former dissolved in a solvent and an electron-accepting developer, wherein the electron-donating color agent is crystal violet lactone. The solvent is a mixture of a triglyceride of a fatty acid having at least one of the constituent fatty acids having a hydroxyl group, and a vegetable oil having a fatty acid residue composition having an oleic acid residue content of 10 to 60% by weight. material. 2. The mixing ratio of triglyceride and vegetable oil is
The recording material according to claim 1, which is in the range of 8: 2 to 1: 9 by weight. 3. The recording material according to claim 1, wherein the triglyceride is castor oil.