JP2003094804A - Pressure sensitive copying developing sheet and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure sensitive copying developing sheet, on which a high speed coating with a blade coater can be realized without developing bleeding and which is excellent in color developing properties, plate wearability and workability, and its manufacturing method. SOLUTION: In the pressure sensitive copying developing sheet, which is formed by providing a coating layer consisting of a coating composition mainly made of a pigment, an adhesive and a developer with the blade coater on a base sheet, the coating composition consists of 100 mass parts of the pigment composing of 20 to 50 mass parts of a heavy calcium carbonate and 30 to 50 mass parts of a light calcium carbonate as the pigment, the adhesive composing of 2 to 15 mass parts of a starch or at least one kind of starch derivatives and 2 to 10 mass parts of a styrene-butgadiene copolymerized latex and 5 to 50 mass parts of the developer. With this composition, the high speed coating with the blade coater can be realized without developing bleeding under the realization of the excellent color developing properties and plate wearability and its manufacturing method is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-sensitive coating characterized by being capable of coating without causing bleeding even in a high-speed coating system using a blade coater, and having excellent coloring properties, printing durability, and workability. The present invention relates to a color developing sheet for copying and a manufacturing method thereof.

[0002]

2. Description of the Related Art A color image can be obtained by a contact reaction between an electron-donating, almost colorless organic compound (hereinafter referred to as a color former) and an electron-accepting solid acid (hereinafter referred to as a developer). It has been known since ancient times. As a specific application of this development, for example, pressure-sensitive copying paper (US Pat. No. 2,505,470)
No. 2505489) and thermosensitive recording paper (Japanese Patent Publication No. 45-14039).

The pressure-sensitive copying paper comprises a color-developing sheet prepared by dissolving a color-developing agent in a solvent, encapsulating it in a microcapsule, and coating it on a base sheet; and a color-developing sheet obtained by coating a color-developing agent. It consists of a sheet coated on both sides of a single base sheet.

In recent years, the pressure-sensitive copying color developing sheet is mainly manufactured by a blade coater, and in the production process, there is an increasing tendency to increase the coating speed year by year in order to improve productivity.

One of the problems in increasing the speed is a phenomenon called bleeding. This is thought to occur as follows. In the case of a blade coater, control of the coating amount is performed by pressing the doctor blade against the base sheet to be coated, but the pressing pressure increases as the coating speed increases. On the other hand, after the coating liquid to be coated is supplied to the base sheet, the water content of the coating liquid permeates mainly into the base sheet, causing an increase in concentration and a decrease in fluidity. When the coating liquid having reduced fluidity passes through the gap between the blade and the base sheet, the coating liquid remains as droplets or calcified solid matter at the blade tip due to the pressure difference before and after the passage.

If this occurs, it causes coating unevenness, paper breakage, and the like, and the workability is significantly impaired.
In order to suppress this bleeding, reducing the high shear rate viscosity of the coating solution during coating is an effective means, but if the concentration of the coating solution is reduced to reduce the high shear rate viscosity, The working liquid composition sinks, and as a result, the developer loses its ability to develop color. Attempts to lower the high shear rate viscosity by changing the composition of the coating solution often lead to a reduction in printing durability.

In order to suppress this bleeding, the coating liquid is often applied in a state where the concentration is as low as possible and the high shear rate viscosity is low. However, the low concentration of the coating liquid
This means that the load in the drying step becomes large, which is a factor controlling the speeding up, and this causes an increase in binder migration. Binder migration, especially latex migration, hinders color development and leads to a decrease in color density.

As described above, a color-developing color-developing sheet for pressure-sensitive copying characterized by being capable of high-speed coating with a blade coater without causing bleeding and being excellent in color development, printing durability, and workability, and its production. The development of methods has been strongly desired.

[0009]

An object of the present invention is that even high-speed coating using a blade coater can be applied without causing bleeding, and is excellent in color developability, printing durability, and workability. A color developing sheet for pressure-sensitive copying and a method for manufacturing the same.

[0010]

The present inventor, from the above-mentioned present circumstances, can perform high-speed coating using a blade coater without causing bleeding, and is excellent in color developability, printing durability and workability. A pressure-sensitive color developing sheet for producing a pressure-sensitive copying sheet and a method for producing the color-sensitive sheet for producing a pressure-sensitive copying sheet, which is confirmed to have a remarkable effect as a result of repeated studies from the viewpoint of formulation of a coating liquid. And finally came to complete the present invention.

That is, the pressure-sensitive copying color developing sheet of the present invention is a pressure-sensitive copying in which a coating layer comprising a coating composition containing a pigment, an adhesive and a color developing agent as a main component is provided on a base sheet. In the developer sheet for use, the coating composition contains 2 as a pigment.
100 parts by weight of the pigment containing 0 to 50 parts by weight of heavy calcium carbonate and 30 to 50 parts by weight of light calcium carbonate, 1 to 15 parts by weight of at least one starch or starch derivative as an adhesive, and styrene. The butadiene copolymer latex is 1 to 10 parts by mass and the color developer is 5 to 50 parts by mass.

The color-developing color developing sheet according to the present invention comprises:
A pressure-sensitive copying color developing sheet, comprising a base sheet and a coating layer comprising a coating composition containing a pigment, an adhesive and a color developing agent as main components, wherein the coating composition is used as a pigment. ~ 4
100 parts by weight of the pigment containing 0 parts by weight of heavy calcium carbonate and 40 to 50 parts by weight of light calcium carbonate, 2 to 15 parts by weight of at least one starch or starch derivative as an adhesive, and styrene-butadiene copolymer The polymer latex is 2 to 10 parts by mass and the developer is 5 to 50 parts by mass, and the styrene-butadiene copolymer latex has a gel content of 8
It is characterized by being 0% or more, an average particle diameter of 150 to 200 nm, a glass transition temperature of -10 to 20 ° C, and a non-nitrile copolymer latex.

In the above invention, the organic developer is preferably an aromatic carboxylic acid metal salt.

Further, the method for producing the color-developing color developing sheet according to the present invention is the same as the method for producing the pressure-sensitive copying color developing sheet according to the first or second invention, wherein the liquid concentration is 36% by mass or more and the shear rate is A coating liquid having a viscosity of 100 mPa · s or less as measured by a capillary viscometer at 10 ⁵ 1 / s, which is applied on a base sheet by a blade coater at a coating speed of 1000 m / min or more. is there.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION According to the first aspect of the present invention, for pressure-sensitive copying, a base sheet is provided with a coating layer made of a coating composition containing a pigment, a developer and an adhesive as main components. In the color-developing sheet, the coating composition contains 20 to 20 as a pigment.
100 parts by mass of the pigment containing 50 parts by mass of heavy calcium carbonate and 30 to 50 parts by mass of light calcium carbonate,
As an adhesive, a blade coater was used, with 2 to 15 parts by mass of at least one of starch or starch derivative, 2 to 10 parts by mass of styrene-butadiene copolymer latex, and 5 to 50 parts by mass of developer. Provided is a color-developing color developing sheet for pressure-sensitive copying, which is capable of being coated without causing bleeding even at high-speed coating and is excellent in color development.

The first aspect of the present invention will be described in more detail below. The pigment used in the coating liquid for the color-developing color developing sheet of the first invention of the present invention is characterized by using 30 to 50 parts by mass of heavy calcium carbonate and 20 to 50 parts by mass of light calcium carbonate. In this case, if the amount of the heavy calcium carbonate used is less than 20 parts by mass, the water retention is insufficient and the effect of suppressing bleeding deteriorates. Further, when the amount of light calcium carbonate used is less than 30 parts by mass, the coloring property is deteriorated. In the present invention, the combined use of other pigments is not limited.

As an adhesive used in the coating liquid for the color-developing color developing sheet of the first invention, 2 to 15 of at least one starch or starch derivative is added to 100 parts by weight of the pigment.
Parts by weight and styrene-butadiene copolymer latex 2 to 10
It is characterized by including parts by mass. By using starch or starch derivative, the high shear rate viscosity of the coating liquid can be reduced, and by using styrene-butadiene copolymer latex, good printing durability can be achieved without impairing color development. To do. With a latex other than the styrene-butadiene copolymer type, the color developability may be impaired.

The starch or starch derivative used in the present invention is not particularly limited, and examples thereof include starch, dextrin, dialdehyde starch, phosphoric acid starch, oxidized starch, enzyme-modified starch and cationized starch.

The adhesive used in the present invention is characterized in that the starch or starch derivative is contained in an amount of 2 to 15 parts by mass and the styrene-butadiene copolymer latex is contained in an amount of 2 to 10 parts by mass. The viscosity increases and the effect of suppressing bleeding deteriorates, and if it is too small, the effect as an adhesive cannot be achieved.

As the adhesive, for example, polyvinyl alcohol, casein, styrene-butadiene latex, acrylic latex, styrene-acrylic latex, acrylic-butadiene latex, vinyl acetate latex, gelatin, carboxymethyl cellulose, etc. Although an adhesive may be used in combination, it is possible to coat without causing bleeding even in high-speed coating using a blade coater, and from the purpose of excellent color development while maintaining the required printing durability. It is more preferable to use only a combination of starch or a starch derivative and a styrene-butadiene copolymer latex.

The present invention is characterized in that the color developer is contained in an amount of 5 to 50 parts by mass with respect to 100 parts by mass of the pigment. If the amount is too small, the coloring effect is small, and if the amount is too large, the effect is further increased. Is not available and is economically disadvantageous.

The color developer used in the present invention is not particularly limited. For example, inorganic clay such as activated clay, acid clay, attapulgite, zeolite, bentonite, silica, aluminum silicate, novolac type phenol resin, salicylic acid derivative, or polyvalent metal salt of salicylic acid derivative can be used. Many salicylic acid resins and polyvalent metal salts thereof have already been proposed as developers. Polyvalent metal salts of co-condensation resins such as salicylic acid and α, α′-dialkoxy-p-xylene (JP-A-62-17)
6875, 62-178387, 62-178.
No. 388, No. 63-53092, No. 63-15908.
No. 2, 63-160877, etc.), a polyvalent metal salt of a resin obtained by reacting a salicylic acid derivative having an aromatic substituent with a styrene derivative (JP-A-63-18).
6729), a polyvalent metal salt of a resin obtained by reacting a salicylic acid derivative having an aromatic substituent with a benzyl halide (JP-A-63-254124), and others, JP-A-63-289017. Organic developers such as the described resin polyvalent metal salts are known. In addition, polyvalent metal salt compounds composed of salicylic acids, rosins, and polyvalent metal compounds have also been disclosed as organic developers (Japanese Patent Laid-Open No. Hei 2).
-563 publication). The developer in the first invention of the present invention is also preferably an aqueous dispersion containing an aromatic carboxylic acid metal salt from the viewpoint of excellent color developability.

In the present invention, in addition, if necessary, a dispersant, a pH adjusting agent such as caustic soda or ammonia water, a defoaming agent, a lubricant, a water retention agent, a preservative, a fluorescent dye, a coloring dye or a coloring pigment, etc. Auxiliaries can be used.

According to the second aspect of the present invention, in the color-developing sheet for pressure-sensitive copying, the base sheet is provided with a coating layer made of a coating composition containing a pigment, a color developer and an adhesive as main components. The coating composition contains 100 parts by mass of the pigment containing 20 to 40 parts by mass of heavy calcium carbonate and 35 to 50 parts by mass of light calcium carbonate as a pigment, and at least starch or a starch derivative as an adhesive. 1 to 2
2 to 5 parts by mass of styrene-butadiene copolymer latex
10 parts by mass, 5 to 50 parts by mass of the developer, the styrene-butadiene copolymer latex has a gel content of 80% or more, an average particle size of 150 to 200 nm, a glass transition temperature-
The copolymerized latex of 10 to 20 ° C. and non-nitrile type allows the high speed coating using a blade coater to be applied without bleeding, and is excellent in color development and printing durability. And a developer sheet for pressure-sensitive copying.

The second aspect of the present invention will be described in more detail below. The pigment used in the coating liquid for the color-developing color developing sheet of the second invention of the present invention includes:
It is characterized by using 20 to 40 parts by mass of light calcium carbonate and 40 to 50 parts by mass of light calcium carbonate. When the amount of light calcium carbonate used is less than 40 parts by mass,
Poor color development. In the present invention, the combined use of other pigments is not limited.

The adhesive used in the coating solution for the color-developing color developing sheet of the second invention is, like the first invention, at least one of starch and starch derivatives per 100 parts by mass of the pigment. 2 to 15 parts by mass and 2 to 10 parts by mass of styrene-butadiene copolymer latex.

The starch or starch derivative used in the present invention is not particularly limited as in the first invention.

The styrene-butadiene copolymer latex used in the present invention has a gel content of 80% or more, an average particle size of 150 to 200 nm, and a glass transition temperature of -10 to 20.
It is characterized by being non-nitrile type at ℃. If the gel content is less than 80%, the swelling property of the latex is increased, and the solvent in which the color former is dissolved is trapped,
This leads to a decrease in color development. The higher the glass transition temperature is, the more excellent the color developability is, and it is preferably -10 ° C or higher, but if it is 20 ° C or higher, the printing durability is lowered. The larger the average particle diameter is, the more excellent the color developability is, and it is preferable that the average particle diameter is 150 nm or more. Further, the addition of a nitrile-based compound impairs the color developability and is not preferable.

The present invention is characterized in that the developer is contained in an amount of 5 to 50 parts by mass with respect to 100 parts by mass of the pigment, as in the first invention, and the developer used is particularly limited. Not done. The developer in the second invention of the present invention is also preferably an aqueous dispersion containing an aromatic carboxylic acid metal salt from the viewpoint of excellent color development rate.

In the present invention, as in the first invention, in addition, if necessary, a dispersant, a pH adjusting agent such as caustic soda or ammonia water, an antifoaming agent, a lubricant, a water retention agent, a preservative, a fluorescent dye, Auxiliary agents such as coloring dyes or coloring pigments can be used.

According to a third aspect of the present invention, in the method for producing a color-developing color developing sheet according to the first aspect or the second aspect, the liquid concentration is 36% by mass or more and the shear rate is 10 ⁵ 1.
Viscosity by capillary viscometer at 100 mPa / s
・ By using a coating liquid of s or less and coating on a base sheet with a blade coater at a coating speed of 1000 m / min or more, even high-speed coating using a blade coater can be performed without causing bleeding. And a method of manufacturing a color-developing color developing sheet for pressure-sensitive copying, which is excellent in color developability and workability.

In the third aspect of the present invention, a coating liquid having a concentration of 36% by mass or more and a viscosity of 100 mPa · s or less measured by a capillary viscometer at a shear rate of 10 ⁵ 1 / s is used. It is characterized by As the concentration of the coating liquid increases, the high shear rate viscosity increases, but with the coating liquid of the present invention, defects such as streaks and scratches,
Furthermore, it is unlikely that it will be difficult to control the coating amount. Further, since the coating liquid has a high concentration, binder migration is suppressed and more excellent color developability is realized. However, when the viscosity of the coating liquid with a capillary viscometer at a shear rate of 10 ⁵ 1 / s is higher than 100 mPa · s, the occurrence of bleeding becomes a problem.

In the present invention, the capillary viscometer is
"ACAV" manufactured by ACA Systems Oy was used, and the measurement conditions were a pressure of 200 bar and a capillary inner diameter of 0.5 mm.

In the present invention, the coating speed is 1000 m.
/ Min or more. There is no particular upper limit to the coating speed, but in order for the effects of the present invention to be sufficiently exerted, 2000 is taken into consideration in consideration of operational problems such as paper breakage.
It is preferably m / min or less. If it is less than 1000 m / min, the binder migration tends to be increased, the color development tends to be impaired, and it is not preferable in terms of production.

[0035]

EXAMPLES The present invention will be described in more detail below with reference to examples, but of course the present invention is not limited to these examples.

(A) Synthesis of salicylic acid resin 3,5-di (4-methylbenzyl) salicylic acid 6.9 g
(0.02 mol), 50 ml of ethyl ether and 12 g of sulfuric acid as a catalyst were charged into a glass reactor and the temperature was maintained at 20 to 30 ° C. with stirring. Then, at the same temperature, 6.24 g (0.06 mol) of styrene was added dropwise over 8 hours for reaction. After dropping, the mixture was aged at the same temperature for 8 hours, warm water was added, the solvent was distilled off, and the deposited precipitate was filtered. This was vacuum dried to obtain 13.0 g of a white resin. The obtained resin has a weight average molecular weight of 1380 and a softening point of J
It was 62.0 ° C. when measured by a ring and ball softening point measuring device according to IS-K-2548.

(B) Synthesis of Salicylic Acid Resin Polyvalent Metal Salt 10 g of the resin obtained in (a) and 0.65 g of caustic soda were dissolved in 200 ml of hot water with stirring. Then, while maintaining the temperature of the solution at 30 to 35 ° C., 30 m of water was previously added.
3 g of an aqueous solution prepared by dissolving 2.5 g of zinc sulfate heptahydrate in 1
Dropped in 0 minutes. A white precipitate was deposited, and the mixture was stirred at the same temperature for 2 hours, filtered, washed with water, and dried.
10.5 g (yield quantitative) of white powder was obtained. This was a zinc salt of a salicylic acid resin, and the result of analyzing the zinc content was 4.82%.

(C) Preparation of Salicylic Acid Resin Metal Salt Developer Dispersion Liquid Using the metal salt of salicylic acid resin obtained in (b) as a developer, a suspension prepared by dispersing with a sand grinding mill in the following composition It was created.

[0039]   Salicylic acid resin metal salt developer dispersion compound Salicylic acid resin metal salt developer 10 parts by mass 10% polyvinyl alcohol aqueous solution (Kuraray # 117) 3 parts by mass 22.5 parts by weight of water

Examples 1 to 13 and Comparative Examples 1 to 13
In the above, bleeding was evaluated by visual evaluation, and 1
It was evaluated by the 0-point method. 10 points are excellent, no bleeding is observed at all, 1 point is inferior, bleeding occurs immediately after the start of operation, and there is a problem in operation.

Examples 1 to 13 and Comparative Examples 1 to 13
In the evaluation of color development, the color development sheet for blue color development (Mitsubishi NCR Paper Super N-40) and the color development sheet are overlapped so that both coating surfaces face each other, and the nip pressure is 100.
The color density was evaluated 1 minute after passing through a calendar roll of kg / cm ² . The evaluation was carried out by a 10-point method, 10 points being excellent and showing good color development, 1 point being inferior and showing a low color density and a problem.

Example 1 Commercially available heavy calcium carbonate (Escalon 150) as a pigment
0) 40 parts by mass, commercially available light calcium carbonate (Tamapearl 121) 40 parts by mass, commercially available secondary kaolin (Ultra Coat) 20 parts by mass, and commercially available polyacrylic acid-based dispersant (Aron T-40) 0.2 parts by mass. After adding and dispersing with a disperser, commercially available phosphate esterified starch (MS4
600) 10 parts by mass, commercially available styrene-butadiene copolymer latex 5 parts by mass, further 30 parts by mass of salicylic acid resin metal salt developer dispersion, water is added, and a coating liquid for a color developing sheet is applied at a coating liquid concentration of 38 parts by mass. Created to be%. A dry coating amount of 4.5 g / m 2 is obtained using this coating solution for color developing sheet.
² was applied with a blade coater equipped with a steel blade at 800 m / min, and dried to obtain a color developing sheet for pressure-sensitive copying. The bleeding evaluation was at a level of 8 points, confirming good operability. The color development evaluation was 8 points, confirming good color development.

Example 2 All the same as Example 1 except that the pigment was changed to 50 parts by mass of commercially available heavy calcium carbonate (Escalon 1500) and 50 parts by mass of commercially available light calcium carbonate (Tamapearl 121). Went to. The bleeding evaluation was 7 points, and the coloring property evaluation was 10 points.

Example 3 In Example 1, the pigment was used in an amount of 50 parts by weight of commercially available heavy calcium carbonate (Escalon 1500), 40 parts by weight of commercially available light calcium carbonate (Tamapearl 121), and 10 parts by weight of commercially available secondary kaolin (ultra coat). Except changed to
All were carried out in the same manner as in Example 1. Bleeding rating is 8
The evaluation of the color development property was 9 points.

Example 4 In Example 1, 40 parts by mass of commercially available heavy calcium carbonate (Escalon 1500), 50 parts by mass of commercially available light calcium carbonate (Tamapearl 121), and 10 parts by mass of commercially available secondary kaolin (Ultra Coat) were used. Except changed to
All were carried out in the same manner as in Example 1. Bleeding rating is 7
The point and the color development evaluation were 10 points.

Example 5 In Example 1, the pigment was used in an amount of 20 parts by weight of commercially available heavy calcium carbonate (Escalon 1500), 40 parts by weight of commercially available light calcium carbonate (Tamapearl 121), and 40 parts by weight of commercially available secondary kaolin (ultra coat). Except changed to
All were carried out in the same manner as in Example 1. Bleeding rating is 9
The evaluation was 8 points in terms of color development property.

Example 6 In Example 1, 40 parts by mass of a commercially available heavy calcium carbonate (Escalon 1500), 30 parts by mass of a commercially available light calcium carbonate (Tamapearl 121), and 30 parts by mass of a commercially available secondary kaolin (ultra coat) were used. Except changed to
All were carried out in the same manner as in Example 1. Bleeding rating is 9
The evaluation of the color development property was 7 points.

Example 7 All procedures were carried out in the same manner as in Example 1 except that the adhesive was changed to 10 parts by mass of commercially available phosphoric acid esterified starch (MS4600) and 10 parts by mass of commercially available styrene-butadiene copolymer latex. It was The bleeding evaluation was 7 points, and the color development evaluation was 7 points.

Example 8 All procedures were carried out in the same manner as in Example 1 except that the adhesive was changed to 10 parts by mass of commercially available phosphoric acid esterified starch (MS4600) and 2 parts by mass of commercially available styrene-butadiene copolymer latex. It was The bleeding evaluation was 9 points, and the coloring property evaluation was 9 points.

Example 9 All procedures were carried out in the same manner as in Example 1 except that the adhesive used in Example 1 was changed to 15 parts by mass of commercially available phosphoric acid esterified starch (MS4600) and 10 parts by mass of commercially available styrene-butadiene copolymer latex. It was The bleeding evaluation was 7 points, and the color development evaluation was 7 points.

Example 10 All procedures were carried out in the same manner as in Example 1 except that the adhesive used in Example 1 was changed to 15 parts by mass of commercially available phosphoric acid esterified starch (MS4600) and 5 parts by mass of commercially available styrene-butadiene copolymer latex. It was The bleeding evaluation was 7 points, and the color development evaluation was 8 points.

Example 11 All procedures were carried out in the same manner as in Example 1 except that the adhesive was changed to 2 parts by mass of commercial phosphoric esterified starch (MS4600) and 5 parts by mass of commercial styrene-butadiene copolymer latex. It was The bleeding evaluation was 10 points, and the color development evaluation was 8 points.

Example 12 The same procedure as in Example 1 was carried out except that the amount of the salicylic acid resin metal salt developer dispersion added was changed to 50 parts by mass. The bleeding evaluation was 7 points, and the coloring property evaluation was 10 points.

Example 13 The procedure of Example 1 was repeated, except that the amount of the salicylic acid resin metal salt developer dispersion added was changed to 5 parts by mass. The bleeding evaluation was 8 points and the color development evaluation was 7 points.

Comparative Example 1 In Example 1, 15 parts by mass of commercially available heavy calcium carbonate (Escalon 1500), 40 parts by mass of commercially available light calcium carbonate (Tamapearl 121), and 45 parts by mass of commercially available secondary kaolin (Ultra Coat) were used. Except changed to
All were carried out in the same manner as in Example 1. Bleeding rating is 9
The evaluation of color and color development was 6 points.

Comparative Example 2 In Example 1, 40 parts by mass of commercially available heavy calcium carbonate (Escalon 1500), 20 parts by mass of commercially available light calcium carbonate (Tamapearl 121), and 40 parts by mass of commercially available secondary kaolin (Ultra Coat) were used. Except changed to
All were carried out in the same manner as in Example 1. Bleeding evaluation is 1
The score was 0, and the color development evaluation was 5.

Comparative Example 3 All the same as Example 1 except that the pigment in Example 1 was changed to 40 parts by mass of commercially available heavy calcium carbonate (Escalon 1500) and 60 parts by mass of commercially available light calcium carbonate (Tamapearl 121). Went to. The bleeding evaluation was 6 points and the color development evaluation was 10 points.

Comparative Example 4 All the same as Example 1 except that the pigment in Example 1 was changed to 60 parts by mass of commercially available heavy calcium carbonate (Escalon 1500) and 40 parts by mass of commercially available light calcium carbonate (Tamapearl 121). Went to. The bleeding evaluation was 6 points, and the color development evaluation was 8 points.

Comparative Example 5 The procedure of Example 1 was repeated except that the amount of the commercially available styrene-butadiene copolymer latex was changed to 1 part by mass. The bleeding evaluation was 9 points, and the color development evaluation was 10 points.

Comparative Example 6 The procedure of Example 1 was repeated except that the amount of the commercially available styrene-butadiene copolymer latex was changed to 12 parts by mass. The bleeding evaluation was 6 points and the color development evaluation was 6 points.

Comparative Example 7 The procedure of Example 1 was repeated except that the commercially available styrene-butadiene copolymer latex was changed to the commercially available acrylonitrile butadiene copolymer latex.
The bleeding evaluation was 8 points, and the color development evaluation was 3 points.

Comparative Example 8 In Example 1, a commercially available phosphorylated esterified starch (MS46
The same procedure as in Example 1 was carried out except that (00) was replaced with a commercially available 10% polyvinyl alcohol (PVA) aqueous solution (Kuraray # 117). The bleeding evaluation was 4 points, and the color development evaluation was 8 points.

Comparative Example 9 The procedure of Example 1 was repeated, except that the amount of the salicylic acid resin metal salt developer dispersion liquid was changed to 4 parts by mass. The bleeding evaluation was 8 points, and the color development evaluation was 6 points.

Comparative Example 10 Example 1 was repeated except that the amount of the salicylic acid resin metal salt developer dispersion was changed to 60 parts by mass.
I went the same way. The bleeding evaluation was 6 points and the color development evaluation was 10 points.

Comparative Example 11 The procedure of Example 1 was repeated except that the salicylic acid resin metal salt developer dispersion was changed to a commercially available inorganic developer (Silton DR-1). The bleeding evaluation was 6 points and the color development evaluation was 5 points.

[0066]

[Table 1]

As is clear from the results in Table 1, for pressure-sensitive copying, a base sheet was provided with a coating layer made of a coating composition containing a pigment, an adhesive and a color developer as main components by a blade coater. In the color-developing sheet, the coating composition contains 20 to 50 parts by mass of heavy calcium carbonate as a pigment and 30 to 30 parts by mass.
1 part of the pigment containing 50 parts by weight of light calcium carbonate
00 parts by mass, as an adhesive, 2 to 15 parts by mass of at least one of starch or starch derivative, 2 to 10 parts by mass of styrene-butadiene copolymer latex, and 5 to 50 parts by mass of developer. Thus, a color-developing sheet for pressure-sensitive copying is provided, which can be coated without causing bleeding even in high-speed coating using a blade coater and is excellent in color development.

In Examples 14 to 20 and Comparative Examples 12 to 17, bleeding was evaluated by visual evaluation, and a 10-point method was used. 10 points are excellent, no bleeding is observed at all, 1 point is inferior, bleeding occurs immediately after the start of operation, and there is a problem in operation.

In Examples 14 to 20 and Comparative Examples 12 to 17, the color development was evaluated by applying the pressure-sensitive copy coloring sheet for blue color development (Mitsubishi NCR Paper Super N-40) and the developing sheet. Nip pressure 1
The color density was evaluated 1 minute after passing through a calendar roll of 00 kg / cm ² . The evaluation was carried out by a 10-point method, 10 points being excellent and showing good color development, 1 point being inferior and showing a low color density and a problem.

In Examples 14 to 20 and Comparative Examples 12 to 17, the printing durability was evaluated by printing with an IPI ink using an RI printer (Myo Seisakusho), and the degree of picking on the printed surface was visually judged. did. 1 out of 10
0 is the best level and 1 is the worst level.

Example 14 Commercially available heavy calcium carbonate (Escalon 150) as a pigment
0) 30 parts by mass, commercially available light calcium carbonate (Tamapearl 121) 45 parts by mass, commercially available secondary kaolin (Ultra Coat) 25 parts by mass, and commercially available polyacrylic acid-based dispersant (Aron T-40) 0.2 parts by mass. After adding and dispersing with a disperser, commercially available phosphate esterified starch (MS4
600) 10 parts by mass, styrene-butadiene copolymer latex (gel content 85%, average particle size 160 nm, glass transition temperature 5 ° C., non-nitrile type) 5 parts by mass, and further 30 parts by mass of salicylic acid resin metal salt developer dispersion. Then, water was added to prepare a coating liquid for the color developing sheet so that the concentration of the coating liquid would be 36% by mass. Using this coating solution for color developing sheet, a dry coat amount of 4.5 g / m ² was applied at 900 m / min with a blade coater equipped with a steel blade, followed by drying. A color developing sheet for pressure copying was obtained. The bleeding evaluation was at a level of 8 points, confirming good operability. The color development evaluation was 9 points, confirming good color development. The printing durability was at a level of 9 points, and good printing durability was confirmed.

Example 15 In Example 14, the styrene-butadiene copolymer latex was changed to a non-nitrile type latex having a gel content of 90%, the average particle diameter and the glass transition temperature were not changed. Except for this, the same procedure as in Example 14 was carried out. The bleeding evaluation was 7, the color development evaluation was 9, and the printing durability evaluation was 8.

Example 16 In Example 14, the styrene-butadiene copolymer latex was changed to a non-nitrile type latex having a gel content of 95%, no change in average particle diameter and glass transition temperature. Except for this, the same procedure as in Example 14 was carried out. The bleeding evaluation was 7, the color development evaluation was 10, and the printing durability evaluation was 7.

Example 17 In Example 14, the styrene-butadiene copolymer latex was mixed with the gel having a mean particle size of 150 nm and a gel content of
The same procedure as in Example 14 was performed except that the glass transition temperature was not changed and the glass transition temperature was changed to a non-nitrile type. The bleeding evaluation was 8 points, the color development evaluation was 8 points, and the printing durability evaluation was 9 points.

Example 18 In Example 14, the styrene-butadiene copolymer latex was used, the average particle size was 200 nm, the gel content was
The same procedure as in Example 14 was performed except that the glass transition temperature was not changed and the glass transition temperature was changed to a non-nitrile type. Bleeding evaluation is 7 points, color development evaluation is 10 points,
The printing durability evaluation was 9 points.

Example 19 In Example 14, the styrene-butadiene copolymer latex was changed to a non-nitrile type having a glass transition temperature of −10 ° C., no change in gel content and average particle size. Except for the above, the same procedure as in Example 14 was carried out. The bleeding evaluation was 8 points, the color development evaluation was 7 points, and the printing durability evaluation was 10 points.

Example 20 In Example 14, the styrene-butadiene copolymer latex was mixed with a glass transition temperature of 20 ° C. and a gel content of
The average particle size was not changed, and the same procedure as in Example 14 was performed except that the average particle size was changed to a non-nitrile type. The bleeding evaluation was 8 points, the color development evaluation was 10 points, and the printing durability evaluation was 7 points.

Comparative Example 12 In Example 14, the styrene-butadiene copolymer latex had a gel content of 75%, the average particle diameter and the glass transition temperature were not changed, and was changed to a non-nitrile type. Except for this, the same procedure as in Example 14 was carried out. The bleeding evaluation was 8 points, the color development evaluation was 6 points, and the printing durability evaluation was 10 points.

COMPARATIVE EXAMPLE 13 In Example 14, the styrene-butadiene copolymer latex was used, the average particle size was 130 nm, the gel content was
The same procedure as in Example 14 was performed except that the glass transition temperature was not changed and the glass transition temperature was changed to a non-nitrile type. The bleeding evaluation was 9 points, the color development evaluation was 6 points, and the printing durability evaluation was 9 points.

Comparative Example 14 In Example 14, the styrene-butadiene copolymer latex was used, the average particle size was 220 nm, the gel content was
The same procedure as in Example 14 was performed except that the glass transition temperature was not changed and the glass transition temperature was changed to a non-nitrile type. The bleeding evaluation was 6 points, the color development evaluation was 9 points, and the printing durability evaluation was 8 points.

Comparative Example 15 In Example 14, the styrene-butadiene copolymer latex had a glass transition temperature of −20 ° C., the gel content and the average particle diameter were not changed, and the non-nitrile type was changed. Except for the above, the same procedure as in Example 14 was carried out. The bleeding evaluation was 7, the color development evaluation was 6, and the printing durability evaluation was 5.

Comparative Example 16 In Example 14, the styrene-butadiene copolymer latex was mixed with a glass transition temperature of 30 ° C. and a gel content of
The average particle size was not changed, and the same procedure as in Example 14 was performed except that the average particle size was changed to a non-nitrile type. The bleeding evaluation was 9 points, the color development evaluation was 10 points, and the printing durability evaluation was 6 points.

Comparative Example 17 The same procedure as in Example 14 was carried out except that the styrene-butadiene copolymer latex was changed to a nitrile styrene-butadiene copolymer latex containing 10% acrylonitrile as a monomer composition. It was The bleeding evaluation was 8 points, the color development evaluation was 5 points, and the printing durability evaluation was 9 points.

[0084]

[Table 2]

As is clear from the results in Table 2, for pressure-sensitive copying, a base sheet was provided with a coating layer made of a coating composition containing a pigment, an adhesive and a color developer as main components by means of a blade coater. In the color-developing sheet, the coating composition contains 20 to 40 parts by mass of heavy calcium carbonate and 40 to 40 parts by weight as pigments.
1 part of the pigment containing 50 parts by weight of light calcium carbonate
00 parts by mass, 2 to 15 parts by mass of at least one starch or starch derivative as an adhesive, 2 to 10 parts by mass of a styrene-butadiene copolymer latex, and 5 to 50 parts by mass of a color developing agent. The copolymer latex has a gel content of 80% or more and an average particle size of 150 to 200.
nm, glass transition temperature −10 to 20 ° C., and by being characterized by being a non-nitrile-based copolymerized latex, coating can be performed without bleeding even in high-speed coating using a blade coater, and Provided is a color-developing color developing sheet for pressure-sensitive copying, which is more excellent in color developability and printing durability.

In Examples 21 to 27 and Comparative Examples 20 to 23, bleeding was evaluated by visual evaluation and was evaluated by a 10-point method. 10 points are excellent, no bleeding is observed at all, 1 point is inferior, bleeding occurs immediately after the start of operation, and there is a problem in operation.

In Examples 21 to 27 and Comparative Examples 18 to 21, the coloring property was evaluated by applying the pressure-sensitive copy coloring sheet for blue color development (Mitsubishi NCR paper Super N-40) and the developing surface to both coated surfaces. Nip pressure 1
The color density was evaluated 1 minute after passing through a calendar roll of 00 kg / cm ² . The evaluation was carried out by a 10-point method, 10 points being excellent and showing good color development, 1 point being inferior and showing a low color density and a problem.

In Examples 21 to 27 and Comparative Examples 18 to 21, the workability was evaluated by comprehensively judging coating troubles such as paper breaks and stains caused by bleeding. ○ indicates that there is no problem during coating. △ is a condition where problems rarely occur. × means that the problem frequently occurs.

Example 21 Commercially available heavy calcium carbonate (ESCALON 150) as a pigment
0) 30 parts by mass, commercially available light calcium carbonate (Tamapearl 121) 40 parts by mass, commercially available secondary kaolin (Ultra Coat) 30 parts by mass, and commercially available polyacrylic acid-based dispersant (Aron T-40) 0.2 parts by mass. After adding and dispersing with a disperser, commercially available phosphate esterified starch (MS4
600) 15 parts by mass, commercially available styrene-butadiene copolymer latex 10 parts by mass, further 30 parts by mass of salicylic acid resin metal salt developer dispersion, water is added, and a coating solution for a developer sheet has a coating solution concentration of 40 parts by mass. Created to be%. The viscosity of this coating liquid measured by a capillary viscometer at a shear rate of 10 ⁵ 1 / s was 40 mPa · s. Using this coating liquid for a color developing sheet, a dry coat amount of 4.5 g / m ² was applied at 1000 m / min with a blade coater equipped with a steel blade, followed by drying. A color developing sheet for pressure copying was obtained. The bleeding evaluation was at a level of 7 points, and good operability was confirmed. The color development evaluation was 8 points, confirming good color development. The workability evaluation was good and was good.

Example 22 The same procedure as in Example 21 was carried out except that the concentration of the coating liquid for the color developing sheet was changed to 36% by mass. The viscosity of this coating liquid measured by a capillary viscometer at a shear rate of 10 ⁵ 1 / s was ¹⁵ mPa · s. The bleeding evaluation was 9 points, the color development evaluation was 7 points, and the workability evaluation was ◯.

Example 23 The procedure of Example 21 was repeated except that the concentration of the coating liquid for the color developing sheet was changed to 45% by mass. The viscosity of this coating liquid measured by a capillary viscometer at a shear rate of 10 ⁵ 1 / s was 65 mPa · s. The bleeding evaluation was 8 points, the color development evaluation was 9 points, and the workability evaluation was ◯.

Example 24 The procedure of Example 21 was repeated except that the concentration of the coating liquid for the color developing sheet was changed to 48% by mass. This coating solution had a viscosity of 100 mPa · s measured by a capillary viscometer at a shear rate of 10 ⁵ 1 / s. Bleeding evaluation is 7 points, color development evaluation is 10 points,
The workability evaluation was ◯.

Example 25 The procedure of Example 21 was repeated except that the coating speed of the blade coater was changed to 1200 m / min. The bleeding evaluation was 8 points, the color development evaluation was 8 points, and the workability evaluation was ◯.

Example 26 The procedure of Example 21 was repeated except that the coating speed of the blade coater was changed to 1500 m / min. The bleeding evaluation was 7, the color development evaluation was 8, and the workability evaluation was ◯.

Example 27 The procedure of Example 21 was repeated except that the coating speed of the blade coater was changed to 1800 m / min. The bleeding evaluation was 7, the color development evaluation was 8, and the workability evaluation was Δ.

Comparative Example 18 The same procedure as in Example 21 was carried out except that the concentration of the coating liquid for the color developing sheet was changed to 34% by mass. The viscosity of this coating solution measured by a capillary viscometer at a shear rate of 10 ⁵ 1 / s was 5 mPa · s.
The bleeding evaluation was 10 points, the color development evaluation was 6 points, and the workability evaluation was ◯.

Comparative Example 19 The procedure of Example 21 was repeated except that the concentration of the coating liquid for the color developing sheet was changed to 50% by mass. The viscosity of this coating liquid measured by a capillary viscometer at a shear rate of 10 ⁵ 1 / s was 130 mPa · s. Bleeding evaluation is 6 points, color development evaluation is 10 points,
The workability evaluation was Δ.

COMPARATIVE EXAMPLE 20 The procedure of Example 21 was repeated except that the coating speed of the blade coater was changed to 800 m / min. The bleeding evaluation was 8 points, the color development evaluation was 6 points, and the workability evaluation was ◯.

Comparative Example 21 The same procedure as in Example 21 was carried out except that the coating speed of the blade coater was changed to 2000 m / min. The bleeding evaluation was 6 points, the color development evaluation was 8 points, and the workability evaluation was poor because paper breakage was likely to occur.

[0100]

[Table 3]

As is clear from the results shown in Table 3, claim 1
Alternatively, in the method for producing a color developing sheet for pressure-sensitive copying according to 2, the liquid concentration is 36% by mass or more and the shear rate is 10 ⁵ 1 / s.
Viscosity by capillary viscometer at 100mPa · s
By using the following coating liquid and coating on the base sheet with a blade coater at a coating speed of 1000 m / min or more, even high-speed coating using a blade coater can be performed without bleeding, and Provided is a method for producing a color-developing color-sensitive sheet for pressure-sensitive copying, which is excellent in color developability and workability.

[0102]

As described above, according to the present invention, it is possible to coat without causing bleeding even in high-speed coating using a blade coater, and to have excellent coloring properties, printing durability, and workability. It is possible to obtain the excellent effect of providing the characteristic color developing sheet for pressure-sensitive copying and the manufacturing method thereof.

Claims (4)

[Claims] 1. A pressure-sensitive copying color developing sheet in which a coating layer comprising a coating composition containing a pigment, an adhesive and a color developing agent as main components is provided on a base sheet by a blade coater,
The coating composition contains 100 parts by mass of the pigment containing 20 to 50 parts by mass of heavy calcium carbonate and 30 to 50 parts by mass of light calcium carbonate as a pigment, and at least starch or a starch derivative as an adhesive. 2 to 15 parts by mass of one type, 2 to 10 parts by mass of a styrene-butadiene copolymer latex, and 5 to 50 parts by mass of a color developing agent. 2. A pressure-sensitive copying color-developing sheet in which a coating layer comprising a coating composition containing a pigment, an adhesive and a color-developing agent as a main component is provided on a base sheet by a blade coater.
The coating composition contains 100 parts by mass of the pigment containing 20 to 40 parts by mass of heavy calcium carbonate and 40 to 50 parts by mass of light calcium carbonate as a pigment, and at least starch or starch derivative as an adhesive. 2 to 15 parts by mass of one kind, 2 to 10 parts by mass of a styrene-butadiene copolymer latex, 5 to 50 parts by mass of a color developer, and the styrene-butadiene copolymer latex has a gel content of 80% or more and average particles. Diameter 150-200 nm, glass transition temperature -10-2
A color development sheet for pressure-sensitive copying, characterized in that it is a copolymerized latex of 0 ° C. and non-nitrile type. 3. A color-developing sheet for pressure-sensitive copying according to claim 1, wherein the color-developing agent is an aromatic carboxylic acid metal salt. 4. The method for producing a color-developing color-sensitive sheet for pressure-sensitive copying according to claim 1 or 2, wherein the viscosity is 100 mPa · s at a liquid concentration of 36 mass% or more and a shear rate of 10 ⁵ 1 / s by a capillary viscometer. A method for producing a color-developing color-sensitive sheet for pressure-sensitive copying, which comprises applying a coating solution of s or less on a base sheet with a blade coater at a coating speed of 1000 m / min or more.