JPH02243383A - Composition for detecting damaged microcapsule - Google Patents

Abstract

PURPOSE:To obtain an excellent composition for detecting a damaged microcapsule generating no environmental disruption by filling a spray container with an org. coupler, an org solvent and carbon dioxide. CONSTITUTION:As an org. coupler to be used, there is a phenol derivative, for example, concretely, 2-chloro-4-phenylphenol. As an org. solvent to be used, for example, n-hexane is designated concretely and an especially pref. one is 1,1,1-trichloroethane. Carbon dioxide to be used is mixed as a pressure source for spraying an org. solvent solution of the org. coupler from a container.

Description

Detailed Description of the Invention (A) Industrial Application Field The present invention relates to an image recording material using microcapsules containing an electron-donating dye dissolved in a high boiling point solvent. The present invention relates to a composition for use.

(B) Prior art Image recording materials using electron-donating colorless or light-colored dyes and electron-accepting color developers are known, for example, in U.S. Pat.
No. 480052, Specification No. 4436920, JP-A No. 1973
There are carbonless pressure-sensitive recording materials as described in detail in No. 7-1.79836 and Japanese Patent Publication No. 60-23922.

Carbonless pressure-sensitive recording materials basically consist of a colorless or light-colored electron-donating dye sheet and a color developer sheet.
The electron-donating dye is dissolved in a high-boiling solvent and encapsulated in microcapsules.

Conventionally, microencapsulation methods include coacervation method,
This is carried out by in-situ method, interfacial polymerization method, etc., and examples of colorless or light-colored electron-donating dyes include 3,3-bis(paradimethylaminophenyl) 6-dimethylaminophthalide (crystal violet). lactone), malachite green lactone, triphenylmethane phthalide series such as 3-dimethylaminotriphenylmethane phthalide, 6',8'-dichloro1.3
．． 3-trimethyl-indolino-benzospiropyran,
spiro(3-methyl-benzo(5゜6-a)chromene-
Spiropyrans such as 2,2--7゛-diethylaminochromene; 3-dimethylamino-6-methyl-7-
Fluorane series such as chlorofluorane, 3-diethylamino-7-(0-acetyl)anilinofluorane; 3-
(4-diethylamino-2-ethoxyphenyl)-3-
(1-ethyl-2-methylindol-3-yl)-7
-Azaphthalide series such as azaphthalide: 3゜3-bis(
Indole-based compounds such as 1-octyl-2-methylindol-3-yl) phthalide, N-butyl-3-(bis-[
Triphenylmethane series such as 4-(N-methylanilino)phenylcomethyl)carbazole; 3-diethylamino-7(N-methylanilino)-10-benzoylphenoxazine, 1O-(3°, 4′, 5°-trimethoxy- benzoyl)-3,7-bis(dimethylamino)-
There are phenothiazines such as phenylthiazine, and one and/or two or more of these are used in combination.

Examples of high boiling point solvents include alkylnaphthalenes such as diisopropylnaphthalene and tetrahalide naphthalene; alkylbiphenyls such as isopropylbiphenyl and isobutylbiphenyl; diallylalkanes such as diallylethane such as 1-phenyl-1-xylylethane; Aromatic hydrocarbons such as methane, alkylbenzenes, benzylnaphthalenes, diallylalkylenes, allylindane; carboxylic acid ester compounds such as dibutyl phthalate and dioctyl maleate; phosphoric acid ester compounds such as nitricresyl phosphate ; Vegetable oils such as castor oil, soybean oil, and cottonseed oil, or modified oils thereof; and natural high-boiling fractions (consisting of aliphatic hydrocarbons) such as mineral oils.

Examples of electron-accepting color developers include natural clay minerals such as acid clay and attapulgite clay as inorganic color developers; activated clay obtained by treating acid clay with mineral acids; JP-A-57-15996; There are semi-synthetic solid acids as described above, and organic color developers such as phenol derivatives; salicylic acid derivatives; metal salts of aromatic carboxylic acids; and novolak resins are already in use.

Microcapsules containing the above-mentioned electron-donating dye, a color developer with a suitable particle size, and a suitable binder are placed on a support such as paper (back-coated microcapsules), respectively.
The bottom paper (surface-coated color developer) is further coated and dried as the middle paper (surface-coated color developer, back-coated microcapsules).
Top-bottom, top-middle-bottom, or top-middle-first-middle... If the bottom paper is stacked and pressed with writing or a typewriter, the microcapsules in the pressurized area will be destroyed and the electron-donating dye will be released. When the colorants come into contact, a coloring reaction occurs and an image is obtained. Also, by inserting an inner sheet between sheets, it is possible to make multiple copies.

(C) Problems to be Solved by the Invention Carbonless pressure-sensitive recording materials can be used as slips and office paper. In this way, when used as slips or office paper, it is prepared by printing with colored ink and/or desensitized ink for the purpose of preventing color development as desired.

Common printing methods include offset, letterpress, and flexo/gravure. In most cases, colored ink is printed on the surface of the top paper, the developer surface of the middle paper, and the developer surface of the bottom paper, but in rare cases, it is printed on the microcapsule surface.

Most desensitized inks are printed on the developer side. Particular care must be taken when printing on paper coated with microcapsules; as mentioned above, microcapsules are easily broken by the pressure of a pen or typewriter.

For example, if the microcapsules are broken due to rubbing due to pressure during printing or rubbing against guide rolls due to sheet tension, and this microcapsule paper and color developer paper are combined and stored as slips and office paper. The electron-donating dye solution flows out from the broken microcapsules, transfers to the developer surface, develops color, and becomes unusable.

On the other hand, there are cases where the color developer surface of the stored slips is completely colored. The first question in this investigation is whether or not the microcapsules are broken.

To quantitatively detect damage to microcapsules, dye is extracted from damaged microcapsules using an organic solvent, and its absorbance is measured using a colorimeter. This method is valid and quantifiable in the laboratory. However, at the printing site, measuring instruments such as a colorimeter and organic solvent are required, and the time required for measurement is long. Not appropriate.

Therefore, conventionally, the above-mentioned organic color developer and organic solvent are dissolved in an appropriate concentration, and the solution is applied to sponges, gauze, etc.
There is a method of soaking cotton, a brush, etc., and lightly applying it to the surface of the microcapsules by hand, and then detecting the degree of color development.

However, although it is good for a simple method, it lacks reproducibility. Furthermore, it requires a great deal of time and effort to manually apply the coating to the entire printing sheet, even if only partially, which is not practical.

As an improvement thereof, the metal salt of aromatic carboxylic acid or phenol compound and phenol formaldehyde resin disclosed in JP-A-49-23006 are dissolved in an organic solvent and prepared in a spray gun together with fluorocarbon, propane, and butane gas. Japanese Patent Publication No. Sho 56-5676 describes that a phenolic polymer substance is dissolved in trichlorethylene and perchlorethylene, and an aerosol composition is prepared using a gas such as fluorocarbon, propane, isobutane, or butane as a propellant. Thus, a method of detecting damage by spraying microcapsules onto the surface coated with them has come into actual use.

Currently, the most common injection gas is fluorocarbon gas. Looking at the characteristics of this fluorocarbon gas manufactured by a typical manufacturer, the advantage is that it is nonflammable.
Non-toxic, corrosive and odor free.

The disadvantage is that the typical constituent atoms are carbon, chlorine, and fluorine, which have low polarity in terms of chemical structure, and the solubility of highly polar substances is low.

However, the more serious problem than these is that fluorocarbon gas destroys the environment. There are concerns that it could destroy the ozone layer that surrounds the Earth, which absorbs most of the sun's ultraviolet rays, leading to an increase in the incidence of skin cancer and immune diseases.

On January 1, 1989, the ``Montreal Protocol'' came into effect, with the aim of each country working together to halve the amount of fluorocarbon gas released by the end of this century, and the inventors of the present invention are cooperating with this initiative. There must be.

Therefore, an object of the present invention is to provide a composition for detecting damaged microcapsules that does not cause environmental damage and is excellent when detecting damage to microcapsules on the top or inner paper of a carbonless pressure-sensitive recording material by a spraying method. That's true.

(D) Means for Solving the Problems As a result of extensive research and experiments, the present inventors have developed a composition that does not cause environmental damage and can quickly detect damage to microcapsules.

The present invention is a composition for detecting damaged microcapsules, which is comprised of (1) an organic color developer, (2) an organic solvent, and (2) carbon dioxide, and is filled in a sprayable container.

That is, the inventors of the present invention can detect the degree of damage to microcapsules by spraying the organic color developer from a container containing carbon dioxide and a liquid dissolved in an organic solvent and supplying the spray to the surface on which the microcapsules are coated.

Examples of the organic color developer used in the present invention include phenol derivatives, salicylic acid derivatives, metal salts of aromatic carboxylic acids,
Novolac resins, etc., and specific examples include 2-chloro-4-phenylphenol, 2,2-bis(4-hydroxyphenyl)propane, 4,4'-isopropylidene bis(2methylphenol), 1. 1-bis-(3-chloro-4-hydroxyphenyl)cyclohexane, 2.
2-bis(3-chloro-4-hydroxyphenyl)-3
-Methylbutane, 4. 4'-Secondary-isooctylidene diphenol, 4.4'5ec-butylidenephenol, 4-cyanophenylphenol, 4,4°
-Methylcyclohexylidene diphenol, 1,4-
Bis-4°-hydroxycumylbenzene, 1,4-bis-4′-hydroxybenzoylbenzene, 4,4°
-thiobis(3,6-dimethylphenol), 4,4
° -dihydroxydiphenylsulfone, phloroglycine monobenzyl ether, 4-hydroxybenzophenone, 2,4-dihydroxy 4'-butoxyzenzophenone, 3,3-methylenebis-4-hydroxybenzyl acid benzyl ether, polyvinylphenol, 2,
2',4,4°-telorahydroxydiphenylsulfone, dimethyl 4-hydroxyphthalate, isobutyl 4-hydroxybenzoate, 2. 4. 4°-trihydroxy 2′-benzyloxydiphenyl sulfone, 1,
5-bis-p-hydroxyphenylpentane, 1,6-
Bis-p-hydroxyphenoxyhexane, tolyl 4-hydroxybenzoate, 4-hydroxybenzoic acid α-phenylbenzyl ester, m-xylylene bis4-hydroxybenzoic acid ester, phenethyl 4-hydroxybenzoate, 4-hydroxybenzoic acid-p -cumylbenzyl,
4-Hydroxybenzoic acid-cinnamyl ester, 4-hydroxybenzoic acid benzyl ester, 4-hydroxybenzoic acid-m-fluorobenzyl ester, 4-hydroxybenzoic acid-cumyl ester, 4,4I-hydroxy2
・, 2'-dibutylphenyl sulfone, β-phenethylorselinate, cinnamyl orselinate, orselic acid-〇-chlorophenoxyethyl ester, 5,5°
-Methylenebis-2,4-dihydroxybenzyl acid benzyl ester, 0-phenylphenoxyethyl orselinate, m-phenylphenoxyethyl orselinate, 2゜4-dihydroxybenzoic acid-β-3'-t-butyl-4'' -Hydroxyphenoxyethyl ester, bisphenol A bis-p-hydroxybenzoic acid ester, 5-β-p-methoxyphenoxyethoxy-2-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid-p-
Methylbenzyl ether, 2,4-dihydroxybenzoic acid-β-phenoxyethyl ester, 2,4-dihydroxy-6-methylbenzoic acid 0-methylbenzyl ester, bis-4-hydroxyphenylacetic acid phenoxyethyl ester, 4,4° -Diacetyldiphenylthiourea, 3-phenylsalicylic acid, 5-p-α-methylbenzyl-α-methylbenzylsalicylic acid, 5-p-methoxyphenoxyethyloxysalicylic acid, 5-phenoxyethoxysalicylic acid, 5-p-benzyl-α- Aromas such as methylbenzyl salicylic acid, 3-xylyl-5-(α, α-dimethylbenzyl) salicylic acid, 3,5-di(α-methylbenzyl) salicylic acid, 2-hydroxy-1-α-ethylbenzyl-3-naphthoic acid, etc. Group carboxylic acid, 3.5
-Dicyclopentadiethylsalicylic acid, paraphenylphenol formaldehyde resin, and other phenolic resins.

Calcium, magnesium, copper, zinc, tin, barium, cobalt, etc. are used as metal salts of aromatic carboxylic acids, and zinc is particularly effective.

As the organic material used in the present invention, for example, specifically n
-Hexane, toluene, xylene, benzene, petroleum ether, solvent oil (J 152203-59), aromatic naphtha (trade name Swazol), solvent naphtha, 1,1,1
．． Hydrocarbons such as trichloroethane (trade name chlorocene), carbon tetrachloride, trichlorethylene, methylene chloride; ethanol, isopropyl alcohol, benzyl alcohol, ethylene glycol, propylene glycol, dipropylene glycol, acetone, methyl ethyl ketone, ethylene glycol monomethyl ether, etc. The following alcohols are particularly preferred, but 1. have high solubility, 2 have appropriate volatility, and 2 are as nonflammable as possible. 1. 1. ) Lichloroethane, methylene chloride.

Carbon dioxide (hereinafter commonly referred to as carbon dioxide gas) used in the present invention is mixed as a pressure source for spraying an organic color developer organic solvent solution from a container.

The carbon dioxide gas used in the present invention is a stable and safe compound that is finally obtained through the oxidation reaction of carbon compounds, and is an inexhaustible resource in the circulation cycle. Currently, industrial sources of carbon dioxide include crude carbon dioxide, which is produced as a by-product from ammonia synthesis processes and oil refining processes, but advances in absorption and separation technology for these gases have reduced the purity to 98-99% by weight. It can easily be used as an industrial raw material. Industrial carbon dioxide sources include natural gas and fermentation gas, and carbon dioxide-containing plates are also expensive, as well as coal furnace gas, coke heavy oil combustion gas, cracked gas from naphtha and crude oil, water gas, and the production of quicklime, hydrogen gas, etc. It can be separated and recovered from many processes as a by-product.

As the absorption separation method, the hot potassium carbonate method is mainly used, but the Alkajit method and the ethanolamine absorption method, which use an aqueous solution of an amino acid salt such as potassium methylaminopropionate as an absorbent, have also been adopted.

In these absorption methods, acidic gases such as hydrogen sulfide and carbonyl sulfide are also absorbed and included as impurities, and in addition, N
2.02, N2, C01C* H2n + I, H, O
I) As a physical cleaning method, water washing method (wet method) or adsorption with silica, alumina, or activated carbon (
There is a dry method) and (2) chemical cleaning method in which 98 to 99% by weight carbon dioxide gas can be obtained by combining several methods such as a potassium permanganate solution cleaning method and a sodium carbonate solution cleaning method.

Further, by removing impurity gas through a cycle of compression, dehumidification, liquefaction, and flushing, carbon dioxide gas with a purity of 99.99% or higher is obtained and stored.

The carbon dioxide gas used in the present invention is injected from a vaporized carbon dioxide gas cylinder or a liquefied carbon dioxide gas cylinder cooled by a refrigerator or the like into a container containing an organic color developer organic solvent solution and mixed therein.

In the present invention, an organic color developer is prepared by dissolving O in an organic solvent at a concentration of 15 to 10% by weight, particularly preferably 2 to 8% by weight.

If the concentration of these is less than 0.5% by weight, if the degree of damage to the microcapsules is large, sufficient coloring reaction will not be obtained due to excess electron donating dye, and if the concentration exceeds 10% by weight, the degree of damage to the microcapsules will be small. If the organic color developer is used excessively, the image becomes unclear.

As mentioned above, the injection and mixing ratio of the organic color developer solution dissolved in the organic solvent and the carbon dioxide gas of the present invention is sufficient if the organic color developer solution is sprayed from the container, but it is particularly preferable that the organic color developer solution is sprayed from the container. The weight ratio of color developer solution to carbon dioxide gas was 95=5.

(E) Examples Preferred embodiments and excellent effects of the present invention will be specifically explained below using the most typical examples. In addition, all the following percentages represent weight percentages.

Examples 1 to 5, Comparative Examples 1 to 7 Table 1 shows the organic color developer used in Examples 1 to 5 and Comparative Examples 1 to 7, and the concentration in the organic solvent (1,1,1,)lichloroethane). (%) indicates the gas serving as the spray pressure source.

(Left below) Test method: Using Miyakoshi Seisakusho Miaster 18 type printing machine, 394
on (width) x 4000m (length) commercially available Mitsubishi Nc for winding
R paper Bushi Blue medium paper was used and the sheet tension was wound up at a tension detector scale of 10 kg/an (standard tension) and 30 kg/am (additional tension).

Then, the gas-containing liquid shown in Table 1 was sprayed onto the microcapsule-coated surface of the rolled inner paper, and the color reaction was detected.

- Uniformity of color reaction When sprayed, the electron-donating dye solution scatters in the form of fine particles together with the gases listed in Table 1, and the sizes of the fine particles are defined as large, medium, and small mist. The small size of the mist means that it is evenly scattered over the surface to which the microcapsules are applied, and the color reaction with damaged microcapsules becomes uniform, allowing the degree of damage to be clearly detected.

The degree of uniformity of the color reaction was marked as ○, ■, or △.

(O mark: It can be seen that the coloring reaction is uniform and damage is occurring at a constant rate.■ mark: There is presence or absence of a coloring reaction.

That is, since there are slight shadings, it is detected that the damage is not constant. △ mark: There is presence or absence of color reaction, and the degree of damage is unclear. ) Results The gas-containing liquids of Examples 1 to 5 and Comparative Examples 1 to 7 were sprayed onto the microcapsule-coated surface of inner paper rolled up at 10 kg/am, and the results are shown in Table 2. As is clear from the table, in Examples, the microcapsules were not damaged and no color reaction could be detected.

(The following is a blank space) (F) Effect of the invention As is clear from the above, '6 organic color developer of the present invention,
Comprised of an organic solvent and (1) carbon dioxide, by filling it into a sprayable container and spraying it, there was no problem of pollution that would destroy the ozone layer, and an excellent composition for detecting damaged microcapsules could be provided.

Claims (1)

[Claims] A composition for detecting damaged microcapsules, which comprises (1) an organic color developer, (2) an organic solvent, and (3) carbon dioxide, and is filled in a sprayable container.