JPS6341749B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to desensitizers. More particularly, the present invention relates to a desensitizer for suppressing or blocking the coloring function in carbonless pressure-sensitive copying paper using an electron-accepting compound or solid acid for coloring a colorless color former. Generally, pressure-sensitive copying paper consists of paper coated with an electron-donating leuco dye encapsulated in fine capsules and paper coated with an electron-accepting substance or solid acid. When pressurized, the capsule in the pressurized area is destroyed and the leuco dye develops color. The desensitizer is used for the purpose of suppressing or preventing color development by applying it in advance to areas where color development is unnecessary on either the surface coated with the electron-accepting substance or the electron-donating substance. Capsules containing electron-accepting substances and electron-donating substances are uniformly applied to the entire surface of the paper, so it is widely used to apply a desensitizer to either side using a printing machine or the like to remove unnecessary areas. It is. Clay minerals such as acid clay, bentonite, attapulgide, zeolite, and kaolin are known as electron-accepting solid acids. Also, known electron-donating color formers include crystal violet lactone, rhodamine aninone lactone, malachite green lactone, benzoyl leucomethylene blue, Michler's hydrol, and N-allyl leuco auramine. Conventionally known desensitizers include Japanese Patent Publication No. 46-29546;
Polyhydroxy compounds such as those found in Japanese Patent Publication No. 49-19647, Japanese Patent Publication No. 48-6805, etc., Japanese Patent Publication No. 44-27255,
Amine compounds such as those found in Japanese Patent Publication No. 45-21448, hetero compounds such as those found in Japanese Patent Publication No. 33-3921, Japanese Patent Publication No. 15513-1973, etc., Japanese Patent Publication No. 52-156010,
There are polyether compounds such as those found in JP-A-53-97511. Most of these desensitizers are strongly hydrophilic substances and are therefore printed by letterpress printing presses.
It was not possible to use any printing press other than a letterpress printing press. The idea of printing the desensitizer with a printing machine other than a letterpress printing machine, such as an offset printing machine, is to
For example, alkoxyl nucleophilic compounds have been used as desensitizers, but conventional desensitizers have poor printability and bleed resistance, and their desensitizing effects are not sufficient. As a result of intensive research into desensitizers that can be printed not only on letterpress printing machines but also on printing machines other than letterpress printing machines, the present inventors came to invent the desensitizer with excellent desensitizing effects of the present invention. It is something. That is, the desensitizer of the present invention is obtained by subjecting (1) rosin or modified rosin having a carboxyl group to an addition reaction with (2) a compound having a glycidyl group, and if unreacted glycidyl groups remain, further addition reaction is performed. If necessary, (3) is a desensitizer comprising a product reacted with a compound that reacts with a glycidyl group other than (1). The present invention has an excellent desensitizing effect on pressure-sensitive copying paper such as carbonless copying paper, does not bleed into areas where the desensitizer is not printed, and is applicable not only to letterpress printing but also to printing methods other than letterpress printing. The object of the present invention is to provide a desensitizing agent that has excellent printability during printing, is free from yellowing and odor problems that are disadvantageous to conventional desensitizing agents, and is easy to synthesize. The printing ink using the desensitizing agent according to the present invention can be printed by various printing methods such as offset printing and flexo printing in addition to conventional letterpress printing, so it can be used in various printing methods that could not be obtained with conventional desensitizing inks for letterpress printing. has advantages. Many conventional desensitizers have strong hydrophilic properties, and even if you try to use these strong hydrophilic desensitizers for offset printing, the desensitizer will dissolve into the dampening water, making it impossible to print satisfactorily. Not obtained,
The desensitizing effect is also extremely insufficient, and even if conventional desensitizers are printed using letterpress printing, the printing speed cannot be achieved as much as offset printing, and plate making is also troublesome. When the printing ink produced using this ink is printed using an offset printing machine, the printing effect is excellent and the drying properties are also particularly good, making it possible to speed up printing, making plate making easy, and saving a lot of money. It can save labor. When printed with an ink prepared using the desensitizer according to the present invention, a printed matter with good writability and inconspicuous printing can be obtained. The rosin or modified rosin having a carboxyl group according to the present invention is a rosin that is a natural resin, or a rosin that has been modified using the carboxyl group or double bond of a resin acid that is the main component of the rosin, and is a natural resin. Rosin is a resin acid whose main component is abietic acid. Modified rosin with carboxyl groups includes ester gum, cured resin,
These include maleic acid resin, fumaric acid resin, and rosin-modified phenol resin. Among these rosins or modified rosins, resins with a relatively high acid value are preferred from the viewpoint of desensitizing effects, and rosins and maleic acid resins (reaction products of rosin and maleic acid) are preferred.
Or fumaric acid resin (reaction product of rosin and fumaric acid) is particularly preferred. Examples of compounds having a glycidyl group in the present invention include monoglycidyl compounds such as phenyl glycidyl ether, cresyl glycidyl ether, butyl glycidyl ether, polypropylene glycol monoglycidyl ether, allyl glycidyl ether, octylene oxide, olefin oxide, and glycidyl methacrylate; Ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, 1,6
- Obtained from polyglycidyl compounds such as hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, trimethylolpropane triglycidyl ether, diphenylolpropane diglycidyl ether, polyhydric alcohols, polyamines, polyisocyanate compounds and epichlorohydrin. There are polyepoxy compounds etc. In the present invention, when a glycidyl group remains, the compounds to be reacted with the glycidyl group include:
Any compound that reacts with a glycidyl group may be used, such as a compound having an amino group or a compound having a carboxyl group. Examples of compounds having an amino group include monomethylamine, dimethylamine, monoethylamine, diethylamine, isopropylamine, and diisopropylamine. , n-butylamine, n-dibutylamine, isobutylamine, diisobutylamine, sec-butylamine, n
-amylamine, diamylamine, secondary amylamine, secondary hexylamine 2-ethylbutylamine, n-heptylamine, n-ethylhexylamine, dioctylamine, ethylenediamine, propylene diamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, aniline, monomethyl Aniline, N-mono-
n-butylaniline, N-monoamylaniline,
There are amines such as toluidine, chloraniline, cyclohexylamine, monoethanolamine, diethanolamine, and ammonia, and compounds with carboxyl groups include formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, and caprylic acid. , monovalent fatty acids such as pelargonic acid,
There are divalent carboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, and phthalic acid. In addition, acid anhydrides such as phthalic anhydride, maleic anhydride, succinic anhydride, dodecylsuccinic anhydride, hexahydrophthalic anhydride, methylnadic anhydride, pyromellitic anhydride, dichlorosuccinic anhydride, pyromellitic anhydride, chlorendic anhydride, etc. can also be used. In addition, compounds having hydroxyl groups can also be used in the presence of inorganic bases (for example potassium hydroxide) or organic bases (for example tertiary amines) as catalysts. Compounds having such hydroxyl groups include methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, isopropyl alcohol, n-heptyl alcohol, 2-ethylhexyl alcohol, tetradecyl alcohol, furfuryl alcohol, ethylene glycol monomethyl ether, and ethylene glycol. Monoethyl ether, methoxyethyl alcohol, ethylene glycol monoacetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether,
Monohydric alcohols such as diethylene glycol monobutyl ether, diethylene glycol acetate, triethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol,
Examples include polyhydric alcohols such as propylene glycol, dipropylene glycol, polypropylene glycol, and glycerin. In the present invention, when (1) rosin or modified rosin having a carboxyl group is reacted with the glycidyl group equivalent of the (2) glycidyl group-containing compound at a ratio equal to or higher than the carboxylic acid equivalent, (3)(1) There is no need to add compounds that react with glycidyl groups other than (1) rosin or modified rosin having a carboxyl group relative to the glycidyl group equivalent of (2) a compound having a glycidyl group, especially a polyglycidyl compound. If the reaction is carried out at a ratio less than the equivalent, unreacted glycidyl groups will remain, so if necessary, a compound that reacts with glycidyl groups other than (3) and (1) may be further reacted to remove unreacted glycidyl groups. It can be a desensitizer with no residual. If unreacted glycidyl groups remain in the desensitizer, it tends to deteriorate over time and the desensitizing effect decreases over time, so it is preferable that no unreacted glycidyl groups remain in the desensitizer. (2) When reacting a compound having a glycidyl group, especially the glycidyl group equivalent of a polyglycidyl compound, with (1) rosin or a modified rosin having a carboxyl group at a ratio lower than the carboxylic acid equivalent, it is important to avoid the desensitizing effect. The amount is preferably 1/2 or more of the equivalent mole. Depending on the purpose, desired additives such as drying accelerators, other varnishes, solvents, pigments, etc. can be appropriately added to the desensitizer of the present invention to the extent that the desensitizing effect is not inhibited. It is generally known that a carboxyl group and a glycidyl group undergo an addition reaction as follows. (X represents a residue of rosin or modified rosin, and Y represents a residue of a compound having a glycidyl group.) It is known that an amino group, a carboxyl group, or a hydroxyl group and a glycidyl group undergo an addition reaction as follows. There is. (R represents a residue of a compound having an amino group, a carboxyl group, or a hydroxyl group.) The desensitizer obtained by the present invention is an addition product of a monoglycidyl group and a rosin or a modified rosin having a carboxyl group. In the case of things, In the case of an addition product of a diglycidyl compound and a rosin or a modified rosin having a carboxyl group, When a diglycidyl compound, a rosin or a modified rosin having a carboxyl group, and a compound containing an amino group, carboxyl group, or hydroxyl group that reacts with the glycidyl group are reacted, the addition product is (Z is represented by -NH-, -COO-, -O-). When a compound having three or more glycidyl groups in its molecule is subjected to an addition reaction, the ratio of rosin used in the reaction, modified rosin having a carboxyl group, compound having a glycidyl group, amino group, carboxyl group, or compound having a hydroxyl group Therefore, the ends of the molecules of the addition products are different,
Its terminus is represented by one of the forms of formulas (1) to (4). The present invention will be explained below with reference to Examples. Example 1 30 g of rosin and 11.5 g of 1.6 hexanediol diglycidyl ether were placed in a three-necked flask, heated to 150° C. on an oil bath while stirring with nitrogen gas, and kept there. A pale yellow starch syrup-like product was taken out, and it was confirmed by infrared absorption spectroscopy that the characteristic absorption of the glycidyl group (wavelength: 11.0 μm) had disappeared. A desensitizer was synthesized according to the following composition by a similar method.

[Table] Example 5 Rosin-modified maleic acid resin (Hitaratsuku 40M)
Put 40 g and 30.6 g of polyethylene glycol diglycidyl ether (molecular weight 306) into a three-necked flask, stir while blowing in nitrogen gas, and place on an oil bath.
The mixture was kept at 140°C for 2 hours, then 8.8 g of n-butyric acid was added, and the mixture was further kept at 150°C for 3 hours. The starch syrup-like product was taken out, and it was confirmed by infrared absorption spectrum measurement that the characteristic absorption (wavelength: 11.0 μm) of the glycidyl group had disappeared. By a similar method, n-
It was synthesized using the following compound instead of butyric acid.

【table】

[Preparation of desensitizing ink and production of printed matter]

30 parts by weight of titanium white (rutile) and 10 parts by weight of mineral oil were mixed with 60 parts by weight of the compound synthesized in Examples 1 to 17 and Comparative Example 1, and the mixture was kneaded in a ball mill for 24 hours to prepare an ink. These inks and the ink prepared according to Comparative Example 2 were tested using an offset printing tester, and the coating amount was 5.0 g/
m ² on commercially available carbonless pressure-sensitive copying paper. Next, test methods for desensitization effect, bleed resistance, and printability will be shown. [Test method] Color development test Using the above printing paper, apply 100% to a sphere with a diameter of 0.8 mm.
Copying (color development) was carried out by applying a load of 100 g and moving at a speed of 5 m per minute. The color development results are shown in Table 1, and the numerical values indicate the reflective visibility value (abbreviation of visual density, Vis, D) measured with a microdensitometer.

[Table] Bleed resistance test The above printed material and non-desensitized carbonless pressure-sensitive copying paper were stacked together, a load of 10 g/cm ² was applied, and the paper was placed in a constant temperature and humidity room at a relative humidity of 90% and a temperature of 20°C. After being left for one month, a color development test was conducted on the printed matter and the non-desensitized carbonless pressure-sensitive copying paper. The results are shown in Table 2.

【table】

[Table] Printing suitability test Printing suitability was comprehensively judged by ease of printing using an offset printing tester. The results are shown in Table 3.

【table】

【table】

[Table] ○: Good △: Slightly poor ×: Poor From the results shown in Tables 1 to 3, it can be seen that the desensitizer according to the present invention is excellent in desensitizing effect, bleed resistance, and printability.

Claims (1)

[Claims] 1 (1) Rosin or a modified rosin having a carboxyl group and (2) a compound having a glycidyl group are subjected to an addition reaction, and if unreacted glycidyl groups remain, (3) (1) is added as necessary. ) A desensitizer comprising a product obtained by reacting a compound that reacts with a glycidyl group other than ).