JP3205982B2 - Method of manufacturing color-developed sheet for pressure-sensitive copying - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-sensitive copying color developing sheet having suitability for ink jet recording and a method for producing the same.

[0002]

2. Description of the Related Art A pressure-sensitive copying paper is composed of a paper on which a color-forming agent microcapsule composition mainly containing microcapsules containing an oily substance in which an electron-donating organic color-forming agent or the like is dissolved is coated on the back surface of a support. A medium paper on which a color developer composition mainly composed of an electron-accepting color developer that develops color when it comes into contact with the color developer is applied to the surface of the support, and the color former microcapsule composition is applied to the back surface And a lower paper coated with a developer composition on the surface of a support, and generally used in combination of upper paper-lower paper or upper paper-middle paper-lower paper in order of writing pressure, pressure of a printer, etc. The microcapsules are destroyed and the oil dissolving the color former transfers to the color developing layer,
The color is developed by reacting with the color developer. In addition, a self-coloring type pressure-sensitive copying paper in which a color former and a developer are coated on the same surface of a support so that pressure-sensitive recording can be performed with one sheet is also known as one form thereof.

[0003] Pressure-sensitive copying paper is used for various types of slips, and those slips have been used in the form of form printing by offset printing, letterpress printing, or the like. In recent years, along with the technical development of the ink jet recording method, an example in which the ink jet recording method is used for form printing has come to be seen. The use of the ink jet recording method has the advantages that plate making is not required, the format can be easily changed, and the like, and can be used for printing small lots or printing variable information such as bar codes on slips. Ink-jet printing has also become widespread in pressure-sensitive copying paper.

[0004] Developers used in pressure-sensitive copying paper include:
Inorganic color developing agents such as acid clay, activated clay and attapulgite, and organic developing agents such as phenol-formaldehyde resin, polyvalent metal salt of salicylic acid derivative, polyvalent metal salt of terpene phenol resin and polyvalent metal salt of salicylic acid-containing copolymer. Coloring agents are known. However, an ink jet recorded image formed by using an ink jet recording method on a pressure-sensitive copying color developing sheet using a conventional inorganic color developing agent becomes a blurred and unclear image, and has poor water resistance and is wet with water. In addition, there were problems such as a decrease in the density of an ink jet recorded image.

[0005] In order to improve this, it is described that a cationic substance is blended in the color developing layer of the pressure-sensitive copying sheet. However, it is usually desirable that the coating liquid is anionic in order to reduce the viscosity or stabilize the viscosity of the developing layer coating liquid, but a cationic substance is blended in this anionic developing layer coating liquid. In such a case, the coating liquid is thickened or gelled, which makes coating very difficult. In addition, the cationic substance acts on the color developer to lower the color developing ability, the color density of the pressure-sensitive recording decreases, and there is a drawback that sufficient quality as pressure-sensitive copying paper cannot be obtained.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a pressure-sensitive copying color developing sheet using an inorganic color developing agent, when an ink jet recording method is used, the bleeding of an ink jet image or the image when wet with water. It is an object of the present invention to provide a pressure-sensitive copying developed color sheet which prevents a decrease in density and maintains a sufficient color density as pressure-sensitive copying paper.

[0007]

SUMMARY OF THE INVENTION The present invention provides a pressure-sensitive copying color-developing sheets using an inorganic color developer as electron-accepting color developing agent, ethylenediamine pH adjustment Akirairoso paint, di
Ethylene triamine or aqueous ammonia solution
The present invention relates to a pressure-sensitive copying color developing sheet characterized by being carried out using the above.

Conventionally, in a color developing sheet for pressure-sensitive copying using an inorganic color developing agent such as activated clay, a metal salt is sometimes blended as a dispersing agent for dispersing the color developing agent or pigment in water.
Further, if the pH of the color developing layer is small, there are problems such as deterioration of the color image over time and inferior desensitizing effect even when desensitized printing is performed. It is common practice to adjust the pH of the color developing layer coating material to a high value using a metal salt such as acid soda.

[0009] However, when printing is performed by an ink jet recording method on a pressure-sensitive copying color developing sheet provided with such a color developing layer, the recorded image has only bleeding or poor water resistance. According to the study of the present inventors, when adjusting the color developing layer coating, when a metal salt-based substance such as a dispersant or a pH adjuster is not blended, there is no bleeding of the ink jet recorded image, and the water resistance is good. there were. However, if the paint pH is 9
If the adjustment is not made as described above, the deterioration of the color image over time when the color is formed as the pressure-sensitive copying paper is severe, and the desensitizing effect when the desensitizing ink is printed is reduced.

Therefore, in the present invention, as a result of intensive studies for satisfying both the suitability for ink-jet recording and the suitability for pressure-sensitive recording, ethylenediamine, diethylenetriamine
When the pH of the color developing layer coating is adjusted using either aqueous solution or aqueous ammonia solution, there is no bleeding of the ink jet recorded image, the water resistance is improved, and the deterioration of the pressure-sensitive coloring image can be reduced, and the desensitizing effect can be reduced. It has been found that a good color-developed sheet for pressure-sensitive copying can be obtained, and the present invention has been completed.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Examples of the inorganic color developer used in the present invention include activated clay, acid clay, bentonite, attapulgite, zeolite, montmorillonite, halloysite, kaolinite, and finely powdered silicic acid anhydride.
Activated clay obtained by eluting a part of the base component in the acid clay is particularly preferably used because it exhibits a high color density.

The inorganic pigment contained in the color developing layer of the present invention includes calcium carbonate, magnesium carbonate, zinc oxide,
Titanium oxide, magnesium oxide, aluminum hydroxide,
Examples include, but are not limited to, zinc hydroxide, kaolin, calcined kaolin, silica, barium sulfate, magnesium silicate, aluminum silicate, talc, and the like.

As the binder, starch, sodium alginate, gum arabic, dextrin, glue, gelatin, casein, collagen, viscose, methylcellulose, ethylcellulose, hydroxyethylcellulose, carboxymethylcellulose, polyvinyl alcohol and the like, and acetic acid A vinyl emulsion or the like can be used, but this is not particularly limited.

The developer for the color developing layer of the present invention may contain the above-mentioned color developing agents, pigments, binders and other auxiliaries known in the field of pressure-sensitive copying paper. The method for preparing the coating liquid is not particularly limited, and is appropriately prepared according to a conventional method. The type and amount of the color developer and other various components used in the present invention are determined according to the required performance and recording suitability.
It is appropriate to add about 50% by weight of pigment, 50 to 95% by weight of pigment and 1 to 40% by weight of binder.

[0015] as a pH adjusting agent in the present invention may be used ethylenediamine, diethylenetriamine, or ammonia water solution.

The method for applying the coating liquid is not particularly limited.
It is applied to a substrate such as paper or synthetic paper using an air knife coater, roll coater, blade coater, rod coater, curtain coater, or the like.

[0017]

EXAMPLES Hereinafter, the effects of the present invention will be described in detail with reference to examples and comparative examples, but the present invention is not limited to these examples. In addition, the part and% shown below show a weight part and weight%, respectively.

[Example 1] Activated clay (Silton SS-
100 parts of Mizusawa Chemical Co., Ltd.) are dispersed in 200 parts of water, and the resulting dispersion is treated with SBR latex (trade name: AKDL)
-620, Asahi Kasei Corporation) as dry solids, 15 parts,
A coating solution prepared by adding 40 parts of a 10% solution of oxidized starch (trade name: Oji Ace B, Oji Constarch Co., Ltd.) was adjusted to a coating pH of 10 with an aqueous ammonia solution at 60 g / m using an air knife coater. the coating is a coating weight of about 7.5 g / m ² by dry weight to ² of the base paper, to obtain a pressure-sensitive copying for developing colored paper.

[Example 2] In the same manner as in Example 1 except that the aqueous ammonia solution of Example 1 was changed to diethylenetriamine, a coating material having a coating material pH adjusted to pH 10 was adjusted to 60 g / m ² using an air knife coater. The base paper was coated so as to have an application amount of about 7.5 g / m ² by dry weight to obtain a pressure-sensitive copying developed paper.

Example 3 In the same manner as in Example 1 except that the aqueous ammonia solution of Example 1 was changed to ethylenediamine, the coating material was adjusted to pH 10 by using an air knife coater to adjust the coating material pH to 60 g / m ² . The base paper was coated so as to have an application amount of about 7.5 g / m ² by dry weight to obtain a pressure-sensitive copying developed paper.

Comparative Example 1 A coating material was prepared and applied in the same manner as in Example 1 except that the pH was not adjusted with an aqueous ammonia solution. The pH in this case is p
H7.

[Comparative Example 2] A coating material whose pH was adjusted to 10 was prepared using an air knife coater in the same manner as in Example 1 except that the aqueous ammonia solution of Example 1 was changed to sodium hydroxide. was coated so that the coating weight of about 7.5 g / m ² by dry weight to ² of the base paper.

Comparative Example 3 The procedure of Example 1 was repeated except that the aqueous ammonia solution of Example 1 was changed to sodium silicate.
The paint adjusted to pH 10 was applied to a base paper of 60 g / m ² using an air knife coater to obtain a dry weight of about 7.
The coating was performed so that the coating amount was 5 g / m ² .

Comparative Example 4 pH 10 prepared in Comparative Example 3
Styrene methacrylate quaternary ammonium salt copolymer (trade name: Safomer ST-3100,
A paint was prepared by adding 1.5 parts of a solid component (manufactured by Mitsubishi Yuka Co., Ltd.), but the viscosity was remarkably increased and application was impossible.

Each of the above-mentioned color-developed papers for pressure-sensitive copying was evaluated for suitability as pressure-sensitive copying paper and ink jet printing by the following methods. The results are shown in Table 1. [Suitability of pressure-sensitive copying paper] Color density: Commercial top paper NW40T (Nippon Paper Industries Co., Ltd.)
) And developer paper are overlapped so that the application surfaces face each other,
After calendering at a linear pressure of 50 kg / cm, the color density after 24 hours is measured using a Macbeth densitometer (RD914, Wratten # 106).
Filter, MAKUBETH).
(The larger the value, the better the color development.) Desensitizing effect: A desensitizing ink (trade name: 804-5, manufactured by Nippon Paper Industries Co., Ltd.) is printed on the coated surface, and commercially available upper paper NW40T
Were superposed on each other so that the coated surfaces faced each other, and calendered at a linear pressure of 50 kg / cm. The desensitizing effect was visually determined. ○ Good desensitization effect × Inferior desensitization effect

[Inkjet printing characteristics] Print quality: inkjet printer is BJC-400
Printing was performed using J (manufactured by Canon Inc.), and bleeding of the ink in the printing portion was visually determined. ○ No bleeding × Severe bleeding Water resistance: Printing was carried out using the above-described recording apparatus. After 24 hours had passed since printing, a drop of distilled water was dropped on the printing portion, and the degree of ink jet print density reduction and ink dissolution were measured. Visual determination was made. ○ No print density decrease × Print density decrease

[0027]

[Table 1]

[0028] As is apparent from the results shown in Table 1, ethyl
Rangeamine, diethylenetriamine, or ammonium
In Examples 1 to 3 of the present invention in which pH was adjusted using a near aqueous solution , good results were obtained in suitability for pressure-sensitive copying paper and ink jet printing. In contrast, poor Comparative Example 1, desensitizing effect not conducted pH adjustment, addition, ET
Tylenediamine, diethylenetriamine, or
In the case of Comparative Examples 2 and 3 using a pH adjuster other than the aqueous solution of Monia , the pressure-sensitive coloring density and the desensitizing effect were not affected, but both the ink jet printing quality and the water resistance were very poor. Therefore, in the color developing sheet for pressure-sensitive copying using the ink jet recording method, it can be understood that the pH adjuster of the color developing layer paint has an important effect on the ink jet printing suitability.

[0029]

The developed color sheet for pressure-sensitive copying of the present invention, when printed using an ink-jet recording method, prevents the deterioration of the quality of an ink-jet recorded image when wet with water, and is used as a pressure-sensitive copy paper. Is sufficient, and the desensitizing effect when the desensitizing ink is printed is sufficient, resulting in an extremely excellent pressure-sensitive copying developed color sheet. Further, there is no need to include other additives such as a cationic substance in the color developing layer for imparting water resistance, which is industrially advantageous and practical.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-3-236986 (JP, A) JP-A-57-137183 (JP, A) JP-A-62-85983 (JP, A) JP-A-4- 282888 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41M 5/00 B41M 5/124-5/165

Claims (1)

(57) [Claims] 1. A method for producing a pressure-sensitive copying for color-developing sheet provided with a Akirairoso containing an inorganic color developer on the support, ethylenediamine paint pH of該顕color layer, diethylene tri
A method for producing a color-developed sheet for pressure-sensitive copying, wherein the pH is adjusted to 9 or more with either an amine or an aqueous ammonia solution .