JPS62208985A - Color developer for pressure sensitive paper - Google Patents

Abstract

PURPOSE:To obtain a color developer excellent in economy, by constituting the color developer of a zinc salt of a phenol soluble in an encapsulated oil and a specified salicylic acid compound or a water-insoluble salt thereof. CONSTITUTION:This color developer for a pressure sensitive paper comprises a zinc salt of a phenol soluble in an encapsulated oil and a salicylic aid compound of general formula (I) or a water-insoluble salt thereof. In formula (I), R is hydrogen, a lower alkyl or formula (II) (wherein each of R<3> and R<4>, which may be the same or different, is hydrogen or a lower alkyl), and R<1> is a lower alkyl or formula (III) (wherein R<3> and R<4>) are as defined above). The zinc salt of a phenol soluble in the encapsulated oil is a zinc salt of an alkylnaphthalene, a diarylalkane, an alkylbiphenyl, benzylnaphthalene or the like. The salicylic acid compound may be 3,5-di-t-butylsalicylic acid, 3,5-bis(alpha-methylbenzyl)salicylic acid, 5-(1'-tolyl-1'-methylethyl)salicylic acid or the like. The water-insoluble salt of the compound of general formula (I) may be, for example, a calcium, magnesium, zinc or aluminum slat of the compound. The color developer is excellent in color-developing effect and economical efficiency.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a color developer for pressure-sensitive copying paper.

[Conventional technology]

Pressure-sensitive copy paper is U.S. Patent No. 2712507 and U.S. Patent No. 28.
As described in No. 00457 and No. 3418250, an electron-donating compound (hereinafter referred to as "color developer") dissolved in a high boiling point solvent and incorporated into microcapsules is combined, and both of them are combined. This is a recording paper that utilizes a color reaction upon contact.

Here, the color developer used is conventionally acid clay,
There are inorganic color developers such as kaolin, bentonite, and activated clay, and organic color developers such as various phenolic compounds, novolac type phenolic resins, and polyvalent metal salts of aromatic carboxylic acids. ．．
5-bis(α-methylbenzyl)salicylic acid zinc salt has been widely put into practical use.

[Problem that the invention seeks to solve]

Rose phenylphenol resin is a color developer with relatively strong coloring strength, but the coloring speed is slow, and the colored image may fade when it comes into contact with plasticizers or oils, or the white background may be exposed to sunlight or nitrogen oxidation in the air. It has the disadvantage that it turns yellow when exposed to oxidizing gases. Further, 3,5-bis(α-methylbenzyl)salicylic acid zinc salt is a color developer that has the highest coloring intensity and good storage stability, but has the drawback of being expensive.

[Means to solve the problem]

The present inventors aimed to develop a color developer that exhibits the same performance as 3.5-bis(α-methylbenzyl)salicylic acid zinc salt and has better economic efficiency.
After extensive research, we have completed the present invention.

The present invention provides a phenol zinc salt soluble in capsule oil and a group represented by the general formula [wherein R is hydrogen, a lower alkyl group, or a group represented by 2] (where R3 and R4 are the same or different and hydrogen or lower alkyl R1 represents a lower alkyl group or a group represented by the formula (where R3 and R4 have the same meanings as above). ] This invention relates to a color developer for pressure-sensitive copying paper comprising a salicylic acid compound or a water-insoluble salt thereof.

In the above definition, the lower alkyl group means methyl, ethyl, propyl, isopropyl, butyl, isobutyl, secondary butyl, tertiary butyl, pentyl, isopentyl, neopentyl, and tertiary pentyl.

The phenol zinc salts soluble in capsule oil used in the present invention include alkylnaphthalenes, diarylalkane, alkylbiphenyl, triaryldimethane,
2. It is soluble in fixed oil such as phenylene oxide, alkylbenzene, benzylnaphthalene, etc.
4-ditertiary butylphenol, 2.4-bis(α-methylbenzyl)phenol, 2.4-bis(α,α-dimethylbenzyl)phenol, 2,4-bis(1°-tolylethyl)phenol, 2 .4-bis(1′-tolyl-1°-methylethyl)phenol, 4-tertiary butylphenol, 4-(α-methylbenzyl)phenol,
4-(α,α-dimethylbenzyl)phenol, 4-
(1'-)Lylethyl)phenol, 4-(L'
Preferred are zinc salts of 2,4-disubstituted or 4-substituted phenols, such as, but not limited to, -tolyl-1<-methylethyl)phenol.

In addition, as the salicylic acid compound of formula -i ([), 3.
5-Ditertiary-butylsalicylic acid, 3.5-bis(α-methylbenzyl)salicylic acid, 3.5-bis(α,α-dimethylbenzyl)salicylic acid, 3.5-bis(1°-
Tolylethyl) salicylic acid, 3.5-bis(1°-tolyl-1°-methylethyl)salicylic acid, 5-tert-butylsalicylic acid, 5-(α-methylbenzyl)salicylic acid, 5-(α,α-dimethylbenzyl) ) salicylic acid,
5-(lo-tolylethyl)salicylic acid, 5-(1'
-tolyl-1'-methylethyl)salicylic acid, but are not limited thereto.

Examples of water-insoluble salts of the compound of general formula (1) include calcium, magnesium, zinc, and aluminum.

The color developer for pressure-sensitive copying paper of the present invention is a suitable adhesive (starch, polyvinyl alcohol, gum arabic, water-soluble polymers such as carboxymethyl cellulose, hydroxyethyl cellulose, and styrene-butadiene copolymer,
The coating solution is dispersed or dissolved in water or an organic solvent with other synthetic resin emulsions such as acrylic polymers, etc.) and applied to high-quality paper, and the coating is applied with an air knife coater while cutting the coating process. It can be colored paper. In addition to the above-mentioned ingredients, this 2'/fl contains fillers such as calcium carbonate, talc, clay, titanium oxide, magnesium carbonate, silica, and aluminum silicate, as well as sodium dioctyl succinate, sodium dodecylbenzenesulfonate, and sodium lauryl sulfate. , fatty acid metal salts, fatty acid amides such as ethylene bis fatty acid amide, dispersants such as paraffin wax, ultraviolet absorbers, antifoaming agents,
Conventionally used additives such as waterproofing agents can be appropriately selected and included depending on the purpose.

On the other hand, phthalide dyes such as crystal violet lactone and malachite green lactone, phenothiazine dyes such as benzoylleucomethylene blue, and fluoran color former dyes such as 3-diethylamino-6-methyl-7-anilinofluorane are used by the coacervation method. 5
Microcapsules are formed by the itu method or interfacial polymerization method, and the resulting dispersion is applied to one surface of high-quality paper to form an appropriate amount of microcapsule layer to produce color paper for forming colored images.

Pressure-sensitive copying paper is manufactured by combining the colored paper thus obtained and the colored paper. This copy paper is used by printing under pressure with an electronic typewriter or the like.

The color developer for pressure-sensitive copying paper of the present invention can also be used in combination with a water-insoluble polyvalent metal compound such as zinc oxide.

[For production]

The color developer for pressure-sensitive copying paper of the present invention has excellent coloring effects and economical efficiency. Among these, the combination of the zinc salt of 2,4-disubstituted phenol, which is the raw material for the production of the compound of general formula (■), and the corresponding compound of general formula (I) is currently said to be a high-performance 3,5- Superior to bis(α-methylbenzyl)salicylic acid zinc salt.

〔Example〕

EXAMPLES Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited thereto.

In addition, all "parts" mean "parts by weight."

Example 1 2,4-bis(1′-tolyl-1°-methylethyl)phenol zinc salt ( A 2:1 mixture of m-tolyl and p-)lyl) and 3,5-bis(1
'-)Lilu1'-methylethyl)salicylic acid (
Add and mix 15 parts each of a 2=1 mixture of m-tolyl and p-tolyl (hereinafter the same applies), and weigh this on a scale 140.
g/nl high-quality paper is coated with a coating fi3 g/n ((dry weight)) to make colored paper.

Example 2 In Example 1, 2,4-bis(1'-)mon-
20 parts of 1°-methylethyl)phenol zinc salt; 3.
A colored paper similar to Example 1 was obtained except that 10 parts of 5-bis(1<-tolyl-1<-methylethyl)salicylic acid was used.

Example 3 In Example 1, 2,4-bis(1°-tolyl-1
15 parts of phenol zinc salt (2.4-°-methylethyl)
Except for replacing with 15 parts of di-tert-butylphenol zinc salt.
A colored paper similar to that in Example 1 was obtained.

Example 4 In Example 1, 2,4-bis(1°-tolyl-1
'-methylethyl)phenol zinc salt 15 parts 4-(1
A colored paper was obtained in the same manner as in Example 1, except that 15 parts of phenol zinc salt (-tolyl-1'-methylethyl) was used instead.

Example 5 In Example 1, 2,4-bis(1°-tolyl-1
15 parts of phenol zinc salt (2.4-°-methylethyl)
To 15 parts of a 3:2 mixture of bis(1'-)lylethyl)phenol zinc salt im-tolyl and p-tolyl isomers,
15 parts of 3.5-bis(1°-tolyl-1'-methylethyl)salicylic acid was mixed with 15 parts of 3.5-bis(1°-tolylethyl)salicylic acid (3:2 mixture of m-tolyl form and p-1-sol form). A colored paper similar to that of Example 1 was obtained except that the amount was changed to 15 parts.

Example 6 In Example 1, 2,4-bis(1°-tolyl-1
15 parts of 4-(α-methylethyl)phenol zinc salt
, α-dimethylbenzyl) phenol zinc salt 15 parts,
The same colored paper as in Example 1 was used, except that 15 parts of 3,5-bis(1'-)lylu-1'-methylethyl)salicylic acid was replaced with 15 parts of 3,5-bis(α-methylbenzyl)salicylic acid. Obtained.

Example 7 In Example 1, 2.4-bis(1'-) lylu l°
- 15 parts of 2.4-bis(α-methylbenzyl)phenol zinc salt to 15 parts of 2.4-bis(α-methylbenzyl)phenol zinc salt,
3.5-bis(1°-tolyl-1″-methylethyl)
A colored paper similar to Example 1 was obtained except that 15 parts of salicylic acid was replaced with 15 parts of 3.5-di-tert-butylsalicylic acid.

Example 8 In Example 1, 3,5-bis(1°-tolyl-1
A colored paper similar to Example 1 was obtained, except that 15 parts of 5-tert-butylsalicylic acid was used instead of 15 parts of ``-methylethyl)salicylic acid.

Example 9 In Example 1, 3.5-bis(1°-tolyl-1
A colored paper was obtained in the same manner as in Example 1, except that 15 parts of 3,5-bis(l''-tolyl-1°-methylethyl)salicylic acid zinc salt was used instead of 15 parts of ``-methylethyl)salicylic acid.

Comparative Example 1 In Example 1, 2,4-bis(1°-tolyl-1
15 parts of phenol zinc salt (methylethyl), 3.5-
A colored paper was obtained in the same manner as in Example 1, except that 15 parts of bis(1°-tolyl-1°-methylethyl)salicylic acid was replaced with 30 parts of rosephenylphenol resin.

Comparative Example 2 In Example 1, 2,4-bis(1'-tolyl-1°
-methylethyl)phenol zinc salt, 15 parts of 3.5-bis(1°-tolyl-1°-methylethyl)salicylic acid was replaced with 30 parts of zinc 3.5-bis(α-methylbenzyl)salicylate, etc. A colored paper similar to that in Example 1 was obtained.

Coloring paper to be combined with these colored papers can be obtained, for example, by the following method.

30 parts of crystal violet lactone is dissolved in 370 parts of alkylated naphthalene oil and microencapsulated by a coacervation method to obtain a dispersion. This dispersion liquid was coated on one side of a high-quality paper with a weight of 40 g/rd to obtain a microcapsule layer with a dry weight of 4 g/rd. Example 1
- 9 and Comparative Examples 1 to 2 were printed using an electric typewriter in accordance with the above-mentioned colored paper, and the degree of color development was observed with the naked eye and summarized as color intensity. The results are shown in Table 1.

Table 1: Color development intensity As a result, it became clear that the color development intensity of Examples 1 to 9 was stronger than Comparative example 1 and equivalent to Comparative example 2, and the color development speed of Examples 1 to 9 and The stability of the colored image against plasticizers and oils, and the weather resistance were comparable to Comparative Example 2 and superior to Comparative Example 1.

〔Effect of the invention〕

The colored paper using the color developer for pressure-sensitive copying paper of the present invention is 3.5-
It exhibits color development intensity, color development speed, and color image stability comparable to those using bis(α-methylbenzyl)salicylic acid zinc salt. Therefore, the present invention provides an economical pressure sensitive paper.

Claims (1)

[Claims] Phenol zinc salt soluble in capsule oil and general formula ▲ Numerical formula, chemical formula, table, etc. ▼ [In the formula, R is hydrogen, a lower alkyl group, or the formula ▲ Numerical formula,
There are chemical formulas, tables, etc. ▼ The group represented by (where R^3 and R^4 are the same or different and represent hydrogen or a lower alkyl group),
^1 represents a lower alkyl group or a group represented by the formula ▲Numerical formula, chemical formula, table, etc.▼ (where R^3 and R^4 have the same meanings as above). ] A color developer for pressure-sensitive copying paper comprising a salicylic acid compound or a water-insoluble salt thereof.