JPH02178367A - Desensitizing ink for copy paper - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is a desensitizing ink for pressure-sensitive copying paper, which is particularly free from double images caused by water, has excellent suitability for various types of printing, and has improved desensitizing effects and set-off properties. This invention relates to desensitizing ink for pressure-sensitive copying paper.

(Prior art) Electron-donating or proton-accepting colorless organic compounds (
It has been known for a long time that a colored image is obtained by the reaction between a color former (hereinafter referred to as a color former) and an electron-accepting or proton-releasing agent (hereinafter referred to as a color developer).

Pressure-sensitive copying paper (
For example, US Patent Nos. 2505470, 2505489, 2550471, 2548366, 271
No. 2507, No. 2730456, No. 2730457, No. 3418250, No. 3672935), thermal recording paper (for example, Japanese Patent Publication No. 43-4160, No. 43-760)
No. 0, No. 45-14039, U.S. Patent No. 29 No. 9009
(No.) etc. Furthermore, a printing method is known in which a colored image is obtained by supplying ink containing a color former to a sheet coated with a color developer (German patent application (OL8) 1939962).
issue).

The color developer has the properties defined above and includes clays, phenolic resins, metal salts of aromatic carboxylic acids, and the like.

Generally, in pressure-sensitive copying paper, a combination of a microcapsule-containing layer containing a color former and a color developer layer is used to obtain a colored image. This is done by destroying the microcapsules and bringing the color former and developer into contact.

Generally, these color developers are used as a color developer sheet that is uniformly applied to the entire surface of the support, but depending on the purpose of use of the pressure-sensitive printing paper, there may be areas on the side of the color developer sheet that do not require recording. In such cases, a method of desensitizing the color developer sheet by applying desensitizing ink containing a desensitizing agent to that portion of the color developer sheet using a printing machine or the like is used.

Desensitizing inks used for such purposes are disclosed in, for example, U.S. Pat.
No. 5, No. 45-21448, No. 46-22651,
46-29546, JP 47-32915, JP 47-38201, JP 48-4050, JP 48-6805, JP 49-4484, JP 49-
No. 19647, No. 49-23008, No. 49-238
No. 50, JP-A-49-43708, JP-A No. 49-7200
No. 9, No. 49-77709, No. 49-77710,
No. 49-15513, No. 49-83509, German Patent Filing (OLS) No. 2343800, No. 235
No. 9079, No. 2361856, Special Publication No. 58-381
No. 19, JP-A-63-74681, JP-A-63-41
184 etc. in detail.

(Problem to be Solved by the Invention) Desensitizing inks used for the above purpose generally use a desensitizer, a pigment such as titanium dioxide, a binder, and if necessary a diluent such as an organic solvent. No ink has been found that has an excellent desensitizing effect against various color developers and has good set-off properties. Also, if a desensitizer that is highly soluble in water is used, double images due to water will occur, and if a desensitizer that is insoluble in water is used, the printed area will not be uniform when used for offset printing, which are contradictory characteristics. It had become ink.

Therefore, the object of the present invention is to have excellent printability and 4! rf
It is an object of the present invention to provide a desensitizing ink for pressure-sensitive copying paper which has an excellent desensitizing effect on a color developer, has good set-off properties, and is free from double images due to water.

(Means for solving problems) The above objects are achieved by the invention described below.

That is, the present invention provides a desensitizing ink containing a desensitizer, a pigment, and a binder, in which 4 to 70 moles of an alkylene oxide adduct are used per mole of an amino compound represented by the general formula CI) as a desensitizer. A desensitizing ink for pressure-sensitive copying paper, characterized in that 40 moles or more of the alkylene oxide contains an adduct of butylene oxide.

H2N-CnH2n-N-CH2CH2÷N-CnHz
n-)-NHz (I)HH" In the above formula, m represents O or 1, and n represents an integer of 3 to 6.

As alkylene oxide, 40 moles or more must be butylene oxide, and the remaining 60 molesφ
Ethylene oxide, propylene oxide, prolene oxide, styrene oxide, etc. can be used below, but propylene oxide and butylene oxide are preferred.

This desensitizer exhibits appropriate hydrophobicity even in offset printing that utilizes water repulsion, and has good affinity with resins, so it can be used alone or in combination with conventionally known desensitizers to take advantage of this feature. can do.

Pigments used in the present invention include titanium dioxide.Binders used in the present invention include rosin-modified phenolic resins, ketone resins, polyamide resins, maleic acid resins, phenolic resins, epoxy resins, alkyd resins, and melamine resins.
, Urinary Jujutsuji, Nitrocellulose, Ethylcellulose,
Natural or synthetic polymeric compounds such as butyral resin, polyvinyl alcohol, gelatin, and silica are used.

The desensitizing ink of the present invention can be used with the above composition alone, but if necessary, an organic solvent may be used as a diluent. Examples of organic solvents include linseed oil, tung oil,
These include soybean oil, cottonseed oil, methanol, ethanol, ethyl acetate, toluene, hexane, methyl ethyl ketone, methyl isobutyl ketone, phoriflobylene glycol, polybutylene glycol, and paraffin oil.

The desensitizing ink of the present invention may also contain waxes such as paraffin wax, microcrystalline wax, and carnauba wax, starch, anti-set-off agents such as IJ (IJ), ultraviolet absorbers, antioxidants, etc., as necessary. Can be done.

(Example) 17 parts by weight of a rosin-modified phenol resin (Tamanol T135, manufactured by Marukaku Kagaku Co., Ltd.) was added to 40 parts by weight of the desensitizer shown in Table 1, and the mixture was dissolved at 150°C.

After cooling this melt to 25° C., 25 parts by weight of titanium dioxide and 18 parts by weight of white spindle oil were added and kneaded in a three-roller mill to obtain a desensitized ink for offset and letterpress.

As the test paper, commercially available pressure-sensitive copying paper (Fuji Pressure-Sensitive Paper, manufactured by Fuji Photo Film Co., Ltd.) was used.

The evaluation of the ink is as follows: 1.
00? After applying a load of /nl and combining it with the lower paper for - weeks, the transfer to the lower paper was evaluated as cent off,
In addition, the printed surface and top paper (commercially available Fuji pressure-sensitive paper) were overlapped, and the entire surface was colored using a super calendar, and the "desensitizing effect" and "uniformity" of the desensitizing effect were evaluated.Table 2 It was shown to.

In addition, in the following examples and comparative examples, oxybutylene group,
Oxypropylene groups are abbreviated as BO and PO, respectively.

Table 1 Table 2 ○: Excellent ×: Poor Δ: Slightly inferior (Effects of the invention) The desensitizing ink of the present invention is excellent in printability, set-off property, and desensitizing effect.

Claims (1)

[Scope of Claims] An adduct obtained by adding 4 to 70 moles of alkylene oxide to 1 mole of the amino compound represented by the general formula (I), wherein 40 mole% of the alkylene oxide is added.
A desensitizing ink for copying paper, characterized in that it contains an adduct in which the above is butylene oxide. ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) In the above formula, m represents 0 or 1, and n represents an integer from 3 to 6.