JP2001302949A - Correction ink composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a correction ink composition which provides an excellent solvent resistance and heat resistance of the printed matters, does not interfere with the underlying printed matter independent of its aqueous or oily nature and therefore allows no blur. SOLUTION: The correction ink composition comprises >=30 wt.% organic hollow particle having a ratio of the inner diameter to the outer diameter of >=0.4 and a methyl isobutyl ketone-insoluble content of >=60 wt.%. Methylcyclohexane is used as a solvent in the composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substantially white modified ink composition using organic hollow particles having a high degree of crosslinking.

[0002]

2. Description of the Related Art Conventionally, a correction liquid using a pigment such as titanium oxide as a concealing material has been known to perform concealment correction of characters and the like. However, the pigment is heavy and easily sedimented and re-agglomerated, so that storage stability is difficult. Also, due to the inorganic pigment, the corrected portion is thickened and the rewriting property is poor. Therefore, recently, a white ink using polymer hollow organic particles as a concealing material has been proposed (Japanese Patent Application Laid-Open No. Sho 63-163).
243179, JP-A-63-243180, JP-A-6-166844).

[0003]

However, in a white ink using the above-mentioned conventional organic hollow particles, when a solvent such as thinner is applied to the printed matter, the hollow particles are dissolved.
There was a problem that white printing was discolored. Further, when dried by hot air or exposed to a high temperature of 120 ° C. or more by copying or the like, there is a problem that the hollow particles are also dissolved and the white print is decolorized. In addition, when the print-corrected portion is a print made of water-based ink or oil-based ink, there is also a problem that the printed matter is eroded and bleeding occurs.

The present invention has been made in view of the above circumstances, and has excellent solvent resistance and heat resistance of a printed matter, and does not invade the base printed matter whether it is aqueous or oily. The aim is to provide a modified ink composition which does not.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, when using a specific organic hollow particle and using a specific ink solvent, It has been found that a modified ink composition which is excellent in solvent resistance and heat resistance of printed matter and which does not invade the base printed matter whether it is aqueous or oily, and therefore does not cause bleeding, can be obtained. The invention has been completed.

That is, according to the present invention, the outer diameter is 0.2 to 1 μm.
m, containing 30% by weight or more of organic hollow particles having a ratio of an inner diameter to an outer diameter of 0.4 or more, an insoluble component in methyl isobutyl ketone of 60% by weight or more, and using methylcyclohexane as a solvent. A modified ink composition according to the present invention.

[0007] In this specification, the insoluble component in the organic hollow particles with respect to methyl isobutyl ketone refers to about 1 g (X1) of the organic hollow particles as methyl isobutyl ketone 1.
After stirring for 1 day at 40 ° C. with a stirrer, the mixture was taken out, the weight (X2) after drying was measured, and the insoluble component was calculated as (X2 / X1) × 100 (%). Value.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The organic hollow particles used in the present invention have an outer diameter of 0.2 to 1 μm and a ratio of inner diameter to outer diameter of 0.4.
The outer diameter is preferably 0.3 to 0.7 μm.
m, the ratio of the inner diameter to the outer diameter is 0.5 or more, more preferably the outer diameter is 0.3 to 0.5 μm, and the ratio of the inner diameter to the outer diameter is 0.6 or more. . The upper limit of the ratio between the inner diameter and the outer diameter is not particularly specified, but if it is too large, it is usually difficult to manufacture it. In addition, the organic hollow particles have an insoluble component in methyl isobutyl ketone of 60% by weight or more, preferably 80% by weight or more, and more preferably 90% by weight or more.
It is good that it is more than weight%.

According to such organic hollow particles, the solvent component which has penetrated into the hollow particles when the printed ink is formed by applying the correction ink composition containing the particles to the surface to be corrected and drying to form a printed matter is obtained. As a result, the print is irregularly reflected by the air, and becomes opaque white, thereby exhibiting a function as a correction ink. The printed matter is excellent in solvent resistance and heat resistance. Even if the printed matter is coated with a solvent such as thinner, dried with hot air, or exposed to a high temperature of 120 ° C. or more by copying, it is hollow. There is no worry that the particles are dissolved and the white print is decolorized.

On the other hand, the outer diameter of the organic hollow particles is not more than 0.1.
When the diameter is less than 2 μm or when the ratio of the inner diameter to the outer diameter is less than 0.4, the whiteness based on the above-described action is reduced. When the outer diameter of the organic hollow particles exceeds 1 μm, the same white color is obtained. A large amount of hollow particles is required to obtain the degree, and problems tend to occur in terms of economy and durability of printed matter. Further, when the content of the insoluble component in the organic hollow particles with respect to methyl isobutyl ketone is less than 60% by weight, the solvent resistance and heat resistance of the printed matter are inferior, and a solvent such as thinner is attached to the printed matter,
When dried with hot air or exposed to a high temperature of 120 ° C. or more with a copy or the like, the problem that the hollow particles dissolve and the white print decolorizes easily occurs.

The above-mentioned organic hollow particles used in the present invention have a very high degree of crosslinking, for example, by dissolving a polyfunctional monomer such as methyl methacrylate and divinylbenzene in polystyrene seed. Can be obtained by emulsion polymerization using a water-soluble polymerization initiator. Among the organic hollow particles obtained in this way,
90% by weight of insoluble component in methyl isobutyl ketone
Some of them have the above-mentioned properties, are very excellent in solvent resistance, and have a glass transition temperature of 150 ° C. or more, a thermal decomposition temperature of 300 ° C. or more, and are excellent in heat resistance.

Commercially available organic hollow particles used in the present invention include "SX866 (A)" manufactured by JSR Corporation and related products. In contrast, for example, “SX864 (B)” and “SX865” manufactured by JSR Corporation
(B) "," Ropeg OP made by Rom & Haas Company "
42, Lopeg OP62 and the like have a low crosslink density and the content of insoluble components in methyl isobutyl ketone is less than 60% by weight, and cannot be used as the organic hollow particles of the present invention.

In the present invention, the specific organic hollow particles are used in an amount of 30% by weight or more, preferably 35% by weight or more (generally 70% by weight) in the modified ink composition.
Up to). If the above amount is less than 30% by weight, the whiteness of the printed matter is reduced, and the function as the correction ink composition cannot be achieved.

The ink solvent used in the present invention is methylcyclohexane. When such a specific solvent is used, a conventional general solvent, for example, a water-based solvent, a ketone-based solvent such as methyl isobutyl ketone, or ethanol may be used.
Unlike those using alcohol-based solvents such as
Regardless of whether the underlying printed matter is made of water-based ink or oil-based ink, it does not erode the underlying material, and therefore, when printed on the underlying material, there is no fear of causing bleeding. Absent.

As the binder used in the present invention, urethane resin, α-olefin-maleic acid copolymer resin,
Acrylic resin, styrene-acrylic copolymer resin, rosin resin, vinyl acetate resin, polyvinyl butyral resin,
There are vinyl chloride resin, polyamide resin, epoxy resin, etc., among which urethane resin, α-olefin-maleic acid copolymer resin, acrylic resin, styrene-acrylic copolymer resin, vinyl acetate resin, polyvinyl butyral resin And the like are preferably used.

Commercially available products include "Dianal PB121" and "Dianal PB383" manufactured by Mitsubishi Rayon Co., Ltd.
"Dianal PB122", "Dianal PB12"
3 "," Dynal PB204 "," Dynal P "
B2008 ”or other acrylic resin (with an acid value of 10 mg KOH
/ G or more are particularly good in dispersibility), α-olefin-maleic anhydride copolymer resin partial ester such as “G700” manufactured by Kyoei Chemical Co. (effective for improving flexibility),
"E700", "E755", "E
Urethane resins (effective for adhesion to the underlying printed matter and whiteness) such as "920", "E790", and "E760".

The amount of the binder used is usually 2 to 20% by weight, preferably 3 to 15% by weight, more preferably 5 to 5% by weight, based on the total weight of the correction ink composition.
It is preferably 13% by weight. If the amount of the binder used is too small, the adhesiveness to the underlying printed matter becomes poor,
On the other hand, if the amount is too large, problems such as a decrease in the whiteness of the printed matter and difficulty in printing may easily occur.

[0018]

Next, an embodiment of the present invention will be described in more detail. However, the present invention is not limited only to the following examples. Hereinafter, “parts” means “parts by weight”.

Example 1 Organic hollow particles (“SX866 (A)” manufactured by JSR Corporation, outer diameter: 0.36 μm, ratio of inner diameter to outer diameter: 0.67, solvent-insoluble content in methyl isobutyl ketone: 90 wt. %) 40 parts, acrylic resin ("Dianal PB121" manufactured by Mitsubishi Rayon Co., Ltd., acid value: 180 mgKOH / g) 2
5 parts and 40 parts of methylcyclohexane were mixed and dispersed by a ball mill for 3 hours to prepare a modified ink composition.

Example 2 A modified ink composition was prepared in the same manner as in Example 1, except that the amount of the organic hollow particles (“SX866 (A)” manufactured by JSR) was changed to 50 parts.

Comparative Example 1 As an organic hollow particle, "SX864" manufactured by JSR Corporation was used.
(B) "(outer diameter: 0.55 μm, ratio of inner diameter to outer diameter:
0.50, solvent insoluble content in methyl isobutyl ketone: 30% by weight) except that 40 parts were used.
A modified ink composition was prepared in the same manner as in Example 1.

Comparative Example 2 As organic hollow particles, "SX865" manufactured by JSR Corporation was used.
(B) "(outer diameter: 0.55 μm, ratio of inner diameter to outer diameter:
0.40, solvent-insoluble content in methyl isobutyl ketone: 20% by weight) except that 40 parts were used.
A modified ink composition was prepared in the same manner as in Example 1.

Comparative Example 3 A modified ink was prepared in the same manner as in Example 1 except that 40 parts of a mixed solvent of methyl isobutyl ketone and ethanol at a weight ratio of 1: 1 was used instead of methylcyclohexane. A composition was prepared.

Comparative Example 4 Organic hollow particles ("Ropeg OP42" manufactured by Rom & Haas Company, solid content: 40% by weight, outer diameter: 0.42 μm)
m, ratio of inner diameter to outer diameter: about 0.6, solvent insoluble content in methyl isobutyl ketone: 0% by weight), 140 parts, styrene-acrylic copolymer resin solution ("Jeon Clear" manufactured by Jeonson & Jeonson Co., Ltd.) 52 ", solid content: 60
% By weight], 12 parts of an additive (carbitol), 12 parts of aqueous ammonia (28% by weight of ammonia), 60 parts of water and 20 parts of isopropanol were mixed and dispersed to prepare a modified ink composition. .

The modified ink compositions of Examples 1 and 2 and Comparative Examples 1 to 4 were applied to a black steel plate by an applicator and dried to form printed matter (thickness after drying: 4 μm) )
The initial whiteness was measured with a Macbeth reflection densitometer. Further, thinner was dropped on the printed matter, and the whiteness after drying was measured, and this was defined as the whiteness after the solvent resistance test. Further, the whiteness was measured after leaving the printed matter in a furnace at 120 ° C. for 24 hours, and this was defined as the whiteness after the heat resistance test. In addition, each of the above whiteness degrees is based on Wh of Kodak Company.
item Reflection Coating (6
080) printed on a colorless steel plate in the same manner as above.
It is represented by a relative value of 00%. Further, each of the above-mentioned correction ink compositions was printed on a printed material composed of an aqueous ink and an oil-based ink, and the occurrence of bleeding was examined.
Table 1 shows the results.

[0026]

As is evident from the results shown in Table 1, the modified ink compositions of Examples 1 and 2 exhibited a practical level of whiteness even when printed on a black steel plate, and even when thinner was dropped. It can be seen that even after standing at 120 ° C. for 24 hours, no decrease in whiteness is observed, and no bleeding occurs on any of the aqueous and oily base prints. On the other hand, in the modified ink compositions of Comparative Examples 1 to 4 different from those of the present invention, the solvent resistance and heat resistance of the printed matter are inferior, or bleeding is caused on the aqueous or oily ink printed matter. It can be seen that there are problems such as the occurrence of

[0028]

As described above, according to the present invention, when the outer diameter is 0.2 to 1 μm and the ratio of the inner diameter to the outer diameter is 0.4 or more,
60% by weight of insoluble component in methyl isobutyl ketone
By using the above organic hollow particles and by using methylcyclohexane as an ink solvent,
It is possible to provide a modified ink composition which is excellent in solvent resistance and heat resistance of a printed matter and which does not affect any of the aqueous or oily printed matter of the base and therefore does not cause bleeding.

Claims (1)

[Claims] 1. An organic hollow particle having an outer diameter of 0.2 to 1 μm, a ratio of an inner diameter to an outer diameter of 0.4 or more, and an insoluble component in methyl isobutyl ketone of 60% by weight or more, containing 30% by weight or more. A modified ink composition comprising: methylcyclohexane as a solvent.