JPS6122985A - Solvent for pressure-sensitive reproduction paper - Google Patents

Abstract

PURPOSE:To obtain a solvent for pressure-sensitive reproduction paper which has excellent characteristics in dye solubility, odorlessness and biodegradation by using specific chemical compounds or their mixtures as a solvent for a dyestuff. CONSTITUTION:Subject solvent for pressure-sensitive reproduction paper is a material consisting of compounds or their mixtures as expressed in general formula. In the formula R and R' indicate hydrogen or methyl groups. As for these compounds 1,1-ditolylbutane, 1,1-dixylyl butane, 1,1-trixylylbutane and etc. may be cited. Among the above compounds 1,1-bis (3,4-dimethylphenyl) butane are desirable. Regardless of its weak aromatic characteristics the above solvent has no disagreable odor, but has mutually opposing characteristics such as non-volatility, fluidity and etc., and has no toxicity and is excellent in biodegradation characteristics.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a solvent for pressure-sensitive copying paper, and particularly to a pressure-sensitive copying paper that uses a diarylbutane compound or a mixture thereof as a dye solvent and has excellent dye solubility, odorlessness, and biodegradability. It is related to solvents for use.

In general, pressure-sensitive copying paper companies apply a solution of a colorless coloring agent with color reactivity in the form of microcapsules to one side of a paper sheet, and react with the coloring agent to form a colored product. By applying pressure to a combination of a color developer that can form a color developer applied to the opposite side of another paper sheet, the capsule in the pressurized area is destroyed, and the color developer and primary color agent are separated. It develops color when it comes into contact with it.

In the pressure-sensitive copying paper constructed as described above, the solvent used as the core material of the microcapsules by dissolving the coloring agent (pressure-sensitive dye) transfers the coloring agent (dye) to the color developing layer. It plays an important role as a medium for causing a color reaction, and is required to meet the following requirements ("Paper and Pulp Technology Times", March 1975 issue)
“.

Namely, %' (1) It has a high boiling point, low vapor pressure, is non-volatile, and has little flammability, (2) It is colorless or light-colored and has almost no odor, (3) It has a low viscosity and has good fluidity even at low temperatures. (4) The pressure-sensitive dye has excellent solubility; and (5) the pressure-sensitive dye has been modified and does not inhibit the color development reaction. Especially in the case of resin-based color developers, the color development rate is fast; (6) it is not water-soluble and emulsifiable; (7) it is chemically inert and stable in the air; and (8) it is non-toxic. It has good biodegradability and (
9) It is cheap.

Hitherto, various proposals regarding dye solvents for pressure-sensitive copying paper have been made to meet the above requirements. For example, 2,4-dimethylphenylmethane, 1,1-
Those using G-P-toluylethane etc.
-2126 publication), 1.1-phenylxylylethane, 1#1-soxylylethane, etc. JP-A-47-31718), 1.1-diphenylpropane, 1.1-diphenylbutane (fF
(Kokai No. 48-86615) and the like are known. However, these solvents meet (2) of the above requirements,
(4) and (8) were not necessarily sufficient.

The present invention was made with the purpose of improving the above problems of the conventionally known dye solvents for pressure-sensitive copying paper, and the solvent for pressure-sensitive copying paper of the present invention has the following general formula: or a mixture thereof.

General formula % formula % [In the formula, R and R' represent hydrogen or a methyl group. ] Examples of the compound represented by the general formula of the present invention include 1,1-ditolylbutane, 1,1-ditolylbutane, and 1,1-trilylated xylylbutane. Among these, 1 (d-bis(,4-methylphenyl)butane) represented by the following formula (1) and the 1,1-
Via, (3,4-dimethylphenyl)butane is preferred.

The property of the compound used in the solvent of the present invention is that, as mentioned above, at least one of the two benzene nuclei is bonded to one or more methyl groups and is bonded with +3ζ, 0IbOHI bonds, and is This compound is different from the compounds conventionally known as solvents for pressure copying paper dyes, and is aromatic (
Despite having a low proportion of aromatic nuclear atoms in all carbon atoms, it has no unpleasant odor, is non-volatile and fluid, and is non-toxic and highly biodegradable. be.

The compound represented by the above general formula is obtained by reacting toluene or/and xylene with butyraldebide. However, simply reacting toluene or/and xylene with butyraldehyde does not yield a high yield and high purity target compound. A preferred method for obtaining this compound is as described below.

That is, when reacting toluene or/and xylene with butyraldehyde, a concentration of 86 to 86% is used as a catalyst.
Using 96 wt.
This is a method in which the reaction is carried out at a temperature of 15°C with stirring. In addition,
In the above reaction, in order to prevent coagulation of the sulfuric acid, it is preferable to mix toluene or/and xylene and sulfuric acid at a temperature equal to or higher than the freezing point of sulfuric acid before starting the reaction, and then lower the temperature to the reaction temperature for the reaction. Toluene used as a raw material for the reaction can be used not only as a pure product but also as a mixture with xylene or diluted with an inert solvent such as an aliphatic hydrocarbon. Also,
Xylene may be ortho, meta, or para, or a mixture thereof. In addition, a xylene distillate obtained by thermal cracking, steam cracking, or catalytic reforming of petroleum can be used.

The solvent of the present invention has excellent properties that can be used alone, but it can be mixed with other inert solvents as auxiliary solvents without impairing the properties. The mixing ratio is 2 parts by weight or less of the auxiliary solvent per 1 part by weight of the solvent of the present invention. In addition, examples of the auxiliary solvent include 1-
Examples include indanes such as methyl-3 to phenyl indane, aromatic ethers such as phenylbenzyl ether, and organic acid esters such as maleic acid ester.

In the production of pressure-sensitive copying paper using the solvent of the present invention, conventionally used color formers and color developers can be used without any restrictions. Color formers include, for example, crystal violet lactone (CvL), penzoylleucomethylene burni (B'LMB), malachite green lactone, and diaminofluorane derivatives such as 6-diethylamino-6-methyl-anilinofluorane.

Examples include the body5;i). Moreover, any method may be used for producing the microcapsules, and for example, a coacervation method, an interfacial polymerization method, an internal polymerization method, an external polymerization method, etc. can be applied.

In addition, as a color developer, for example, inorganic substances such as bentonite, zinc oxide, kaolin, creni, activated clay, acid clay, zeolite, talc, colloidal silica, phenol aldehyde polymer, maleic acid-rosin resin, styrene-anhydrous Acidic polymers such as maleic acid copolymer hydrolyzate, ethylene-maleic anhydride copolymer hydrolyzate, carboxypolyethylene 17, vinyl methyl ether-maleic anhydride copolymer hydrolyzate, succinic acid, tannic acid , gallic acid, zinc salicylate, and other carboxylic acids or their metal salts.

As described above, the present invention uses a compound of the general formula having a specific structure as a solvent for dyes for pressure-sensitive copying paper, which has better dye solubility, less odor, and is biodegradable compared to conventional ones. It's also better and safer. Further, since known techniques can be applied to the method of encapsulating the solvent, there are no restrictions on encapsulation.

Next, the present invention will be explained in more detail with reference to Examples.

Example 1゜(1) Production of 1,1-bis(4-methylphenyl)butane 2.0 moles of 94wt xa acid were placed in a 1 ton glass reactor equipped with a stirrer, and 4 moles of toluene α and n-butyraldehyde were added. A mixture of 07 moles of α was continuously added in small portions while stirring at 15°C for 3 minutes, and the temperature of the contents was cooled and maintained at -10°C. Without stirring, 63 moles of n-butyraldehyde and toluene A reaction was carried out by continuously adding dropwise a 160 mol of the mixed solution in small amounts over a period of 4 hours. During this period, the concentration of n-butyraldehyde in the reaction system was less than (L55 parts by weight).After the dropwise addition, stirring was continued at -10°C for 130 minutes.Then, stirring was stopped and the reactor was left standing. , the reaction product is separated and recovered, washed and neutralized with an aqueous solution of sodium carbonate, dried over magnesium chloride, and then subjected to vacuum distillation.
Ditolylbutane containing bis(4-methylphenyl)butane as a main component was obtained in a yield of 9 mmol X (based on n-butyraldehyde).

The chemical structure of this compound is shown in the infrared absorption spectrum, NM
(by R and mass spectra) as follows.

Other properties include boiling point of 120-525℃/7
60ml, viscosity was 7.760 Bt, 40°C, and pour point was 147°C or less.

(2) 1.1-bis(3,4-dimethylphenyl)
Production of butane 4.0 moles of 95% sulfuric acid and 2.1 moles of 0-xylene were placed in the same reactor as in (1) above, and after stirring at 15°C for 1 minute, the contents were cooled to -20°C. 70 mol of n-butyraldehyde α and 2 mol of 0-xylene without stirring.
．． A mixture of 1 mol and 1 mole was continuously added dropwise little by little over 4 hours to cause a reaction. During this time, the concentration of n-butyraldehyde in the reaction system was 15 weight X or less. Even after the dropwise addition was completed, the temperature was maintained at -20°C and stirring was continued for 15 minutes. Thereafter, stirring was stopped, and the reaction product was treated in the same manner as in (1) above to obtain 1,1-bis(g,a-dimethylphenyl)butane in a yield of 96 mol X (based on n-butyraldehyde). The chemical structure of the compound was determined as described below in the same manner as in (1) above. In addition, the boiling point is 360-36
5℃, viscosity 34.8 cst @ 40℃, pour point 121
It was ℃.

CU, Cmi cH.

(3) Production of 1,1-dixylylbutane Into the same reactor as in (2) above, 4.0 mol of 90% sulfuric acid, mixed xylene (58 weight of 0-xylene, 42 weight of m-xylene,
P-*y Ren 20 weight Aldehyde t1A malt Mixed xylene with the above composition!
The L 60% L (1) mixture was continuously added dropwise over 2 hours to cause a reaction. During this time, the concentration of n-butyraldehyde in the reaction system was below a5 weight X. After completion of the dropwise addition, stirring was continued for 15 minutes at 0°C. Thereafter, the stirring was stopped, and the reaction product was treated in the same manner as in (2) above to obtain 1,1-dixylylbutane (methyl group: 50X at the 2nd position, 6ON at the 3rd position,
(4-position is 90X) was obtained in a yield of 89 mol X (based on n-butyraldehyde). The chemical structure line of the compound was determined in the same manner as in (2) above.

Oh! OH Dew OH3 (1) 1,1-bis(4-methylphenylene/L/)butane (1), 1,1-bis(3,
4-dimethylphenyl)butane(II) and 1,1-
Crystal violet lactone was dissolved in dixylbutane (III) by heating to prepare an 8 weight X solution, and the solution was kept at 25°C for 5 days.

Although the device was used for a while, no dye precipitation was observed.

Also, for comparison, 1-7D of the following structure.

Nyl-1-(ys, a-dimethylphenyl)etha]
When a solubility test similar to that described above was conducted for 1,1-bis(3,4-dimethylphenyl)ethane (V) and 1,1-bis(3,4-dimethylphenyl)ethane (V), precipitation of the dye was observed.

(2) The above solvents (1), (1) and Ta.

Example 2 Odor test Solvents in Example 1, 1.1-bis(4-methylphenyl)butane (1), 1.1-bis(3,4-dimethylphenyl)butane (I[] and 1-Dixylylbutane [The odor was judged by a tester and the results are shown in Table 1.

In addition, for comparison, the θ used in Example 1 (for comparison) was 1-phenyl-1-(3,4-dimethyl7enyv)
i 7 (■'), 1,1-bis(4-
Odor tests were similarly conducted on methylphenyl)ethane (Vl) and 1,1-zindinyluptan [■], and the results are shown in Table 1.

Table-1 Example 3 200 ppm of solvent in a 300 volume Erlenmeyer flask.

Activated sludge was charged with a basic culture medium to a concentration of 100 ppm, and cultured in a shaker for 14 days. The biodegradation rate of each solvent was determined by gas chromatography.

The results are shown in Table-2.

Table 2 Example 4 (1) Production of microcapsules 10 parts by weight of gelatin and 10 parts by weight of gum arabic were
It was dissolved in 400 parts by weight of water at 0°C, 0.2 parts by weight of funnel oil was added as an emulsifier, 4 parts by weight of crystal violet lactone was dissolved therein, and then 1,1-bis( 40 parts by weight of (4-methylphenyl)butane was added and emulsified and dispersed. Emulsification was stopped when the size of the oil droplets reached an average of 5 microns, and water at 40° C. was added to make a total of 900 parts by weight, followed by stirring. Then,
10% by weight of acetic acid was added to adjust the pH of the solution to 4.0 to 4.2 to cause icoacervation. This was further stirred for 20 minutes and cooled with ice water to gel the coacervate film deposited around the oil droplets. When the temperature of this liquid reached 20° C., 7 parts by weight of 57% by weight formalin was added. After further cooling the liquid temperature to 10° C., 15% by weight of sodium hydroxide aqueous solution fIL was added to adjust the pH to 9.0. Subsequently, the mixture was heated for 20 minutes while stirring to bring the liquid temperature to 50° C. to complete the curing of the capsules.

One of the pressure-sensitive copying papers, paper A, was obtained by coating the paper. Paper B coated with clay and paper C coated with phenol-aldehyde copolymer are prepared as paper facing pressure-sensitive copy paper A, and the microcapsule-coated side of paper A and paper B and O are coated with paper B and O. When writing under pressure on the non-coated side of paper A with the coated side facing the paper A, a blue image was immediately generated on paper B (3). was found to be sufficiently fast.

Example 5 ←)
87 parts by weight of crystal violet lactone and 57 parts by weight of benzoyl leucomethylene blue were combined with 2,000 parts by weight of 1,1-bis(S,a-dimethylphenyl)butane used in Example 1, and 1 part by weight of commercially available mineral oil [boiling point 180~ 270℃
, specific gravity α796 (15"/4°C)) was added to the mixed oil with 400 parts by weight, and stirred and emulsified to form a dispersion system of oil droplets of 2 to 6 microns. Warm water was further added to this system. In addition, the total amount was adjusted to 32.00 parts by weight, and then 10% by weight of acetic acid was added with stirring to adjust the pH to 4.2.To this, 57% by weight of formalin 80 was added for the purpose of hardening the film.
・After adding 0 parts by weight and holding at 40°C for 60 minutes, 5°C
The microcapsules were cooled until gelatinized, and then a 10% by weight aqueous sodium hydroxide solution was added to adjust the pH to 9.0 to complete the curing of the microcapsules.

(2) Production of pressure-sensitive copying paper Pressure-sensitive copying paper was produced in the same manner as in Example 4 using the microcapsules obtained by the above method. When the obtained copy paper was subjected to pressure printing, it gave a true color, clear, and blur-free copy image.

Claims (3)

[Claims] (1) A solvent for pressure-sensitive copying paper comprising a compound represented by the following general formula or a mixture thereof. General formula ▲ Numerical formula, chemical formula, table, etc. are available ▼ [In the formula, R and R' represent hydrogen or a methyl group. ] (2) The compound represented by the general formula is 1,1-bis(4-
The solvent for pressure-sensitive copying paper according to claim 1, which is (methylphenyl)butane. (3) The compound represented by the general formula is 1,1-bis(3,
The solvent for pressure-sensitive copying paper according to claim 1, which is 4-dimethylphenyl)butane.