JPH06227113A - Method for manufacturing inkjet recording sheet - Google Patents

Abstract

(57) [Summary] [Purpose] A method for producing an ink jet recording sheet capable of effectively preventing curling in a wide range of environments. A method for producing a coat type inkjet recording sheet, comprising an inkjet recording sheet having at least one ink-receiving layer on one side of a support, or a double-sided coated inkjet recording sheet having a backside coating layer on the opposite side. In the manufacturing process of, after the ink receiving layer coating and drying,
A method for manufacturing an inkjet recording sheet, wherein a humidifying treatment is performed on the opposite surface during the next step. [Effect] It is possible to obtain an inkjet recording sheet capable of suppressing curl in a wide range of environments.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an ink jet recording sheet, and more particularly to a method for producing an ink jet recording sheet which can effectively prevent curling in a wide range of environments.

[0002]

2. Description of the Related Art As a recording sheet used in an ink jet recording system, efforts have been made from the viewpoint of equipment and ink composition so as to use high-quality paper or coated paper used for ordinary printing and writing. However, as the performance of the inkjet recording apparatus has been improved and the applications have been expanded, such as high speed, high definition, and full-color of the apparatus, more advanced characteristics have been required for the recording sheet.

As the form of the ink jet recording sheet, plain paper type and high quality paper such as so-called high-quality paper, bond paper and the like, which absorb ink into a support, paper such as high-quality paper, synthetic paper, synthetic resin film and the like are supported. It is roughly classified into a coat type in which an ink receiving layer is provided on the body surface.

Usually, various coated papers including ink jet recording sheets are coated with a coating machine, but if curl occurs in the coated papers, the papers are likely to be broken, which causes deterioration of operability. .

Further, since the ink receiving layer is designed to absorb a large amount of water-based ink as quickly as possible, a change in temperature and humidity causes a difference in expansion and contraction between the ink receiving layer and the support, resulting in curling. Therefore, there arises a problem that the running property is impaired when recording is performed by the normal recording apparatus.

In the field of printing paper, as a curl prevention method, JP-A-62-133198 discloses a curl prevention method using a water coating device, and JP-A-60-9469.
Japanese Patent Publication No. 2 discloses a method in which steam is applied to a cast coated surface to prevent curling.

When these are applied to an ink jet paper and water-coated, water permeates a lot when a low-sized base paper is used, and even penetrates into the ink receiving layer to cause unevenness or the base paper. If the paper is thin, it may run out of paper. Further, even if steam is applied to the ink receiving layer, the effect of preventing curling cannot be obtained, and conversely, curling tends to be bad.

[0008]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an ink jet recording sheet which has no problem in operation and is prevented from curling in a wide range of environments by performing a humidifying treatment on the opposite surface of the ink receiving layer. It is a manufacturing method.

[0009]

That is, the manufacturing method for ink jet recording according to the present invention is such that one side (A side) of a support is
An ink jet recording sheet provided with at least one ink receiving layer, or an ink receiving layer on the side A and the opposite surface (B
In a process for producing an inkjet recording sheet having a back surface coating layer on its surface), after the coating and drying of the A side, a humidifying treatment is performed on the B side during the transition to the next step. Is.

Further, the coating order of the recording sheet is such that after the A side is coated and dried, the B side is coated, or the B side is dried and the A side is coated. A method for manufacturing an ink jet recording sheet, characterized in that after the surface is coated and dried, the surface B is subjected to a humidification treatment during the next step.

Further, the method for producing an ink jet recording sheet is characterized in that the moisture content of the humidifying treatment is in the range of 0.1 to 2.5% by weight with respect to the weight per 1 m ^{2 of} paper.

The basis weight of the support of the recording sheet is 40.
A good effect can be obtained in the range of 200 to 200 g / m ² , preferably in the range of 50 to 130 g / m ² , and the coating amount ratio of the A and B surfaces is A / B = 1/4 to 4 / 1, and the ink-receiving layer is an ink jet recording sheet whose main component is a porous inorganic pigment and whose back coating layer is mainly a hydrohalloysite.

After coating and drying the A side, the B
By subjecting the surface to the moisturizing treatment, the fibers of the B surface are stretched and then contracted, so that curling can be prevented. The amount of water in the humidifying treatment at that time is arbitrarily selected from about 0.1 to 2.5% by weight based on the weight per 1 m ² of paper depending on the purpose and quality characteristics.

In the present invention, the humidifying device for the B side is not particularly limited, and any device may be used. In general, Fludex (FLUI
DEX, made by Hirano Metal Co., Ltd. is used in principle, and steam is sprayed onto the paper from both the top and bottom of the steam chamber, and the steam is condensed by a cooling roll to perform a humidification treatment. Moreover, it is easy to control the amount of humidification, and since it does not come into contact with the paper, there is no hindrance to operability.

In the present invention, even in a device capable of humidifying both sides, only one side (B side) is humidified. If the amount of humidification on side B is small, the curl prevention effect is small,
Further, when the processing amount is large, the curl on the B side becomes too large. Therefore, the amount of humidification treatment is 1 m ² of the above paper.
0.1 to 2.5% by weight is preferable with respect to the weight per unit,
It is preferably adjusted within the range of 0.5 to 1.5% by weight.

Further, in the case of double-sided coating, moisturizing treatment is applied to the B side regardless of the coating order, and the curl is synergistically improved in combination with the curl preventing effect of the B side coating layer. Of.

In the present invention, one or more known white pigments may be used in the ink receiving layer or the back coating layer. For example, light calcium carbonate, heavy calcium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, synthetic non- Crystalline silica, colloidal silica, colloidal alumina, pseudo-boehmite, aluminum hydroxide, alumina, lithopone, zeolite,
Examples thereof include white inorganic pigments such as hydrolyzed halloysite, magnesium carbonate and magnesium hydroxide, organic pigments such as styrene plastic pigments, acrylic plastic pigments, polyethylene, microcapsules, urea resins and melamine resins. Among the above, the white pigment contained as the main component in the ink receiving layer is preferably a porous inorganic pigment, and examples thereof include porous synthetic amorphous silica, porous magnesium carbonate, and porous alumina. Large porous synthetic amorphous silica is preferred.

In the present invention, the coating amounts on the A and B sides are
Depending on the purpose and quality characteristics, about 1 to 30 g / m ^{2 is} arbitrarily selected, but the coating amount ratio of the A and B surfaces is A / B = 1/4 to 4 /
When it is other than 1, the curl prevention effect is reduced.

Examples of the adhesive used in the present invention include polyvinyl alcohol, vinyl acetate, oxidized starch, etherified starch, cellulose derivatives such as carboxymethyl cellulose and hydroxyethyl cellulose, casein,
Gelatin, soybean protein, silyl modified polyvinyl alcohol, etc .; conjugated diene copolymer latex such as maleic anhydride resin, styrene-butadiene copolymer, methyl methacrylate-butadiene copolymer, etc .; acrylic acid ester and methacrylic acid ester polymer Or acrylic polymer latex such as copolymer; vinyl polymer latex such as ethylene vinyl acetate copolymer; or functional group-modified polymer latex with functional group-containing monomer such as carboxyl group of these various polymers Water-based adhesive such as thermosetting synthetic resin such as melamine resin, urea resin; polymethylmethacrylate, polyurethane resin, unsaturated polyester resin,
Examples thereof include synthetic resin adhesives such as vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, and alkyd resin, which are used in one kind or more.

Examples of the support used in the present invention include paper or a sheet material such as synthetic paper and synthetic resin laminated paper such as a photographic support. In the case of paper, addition or non-addition of internal sizing agent, use of sizing agents such as neutral sizing agents, polymer sizing agents, and acidic sizing agents alone or in combination, with or without fillers, size press Does not limit anything. As the internal filler for the paper support, conventionally known pigments are used as white pigments, and they can be used alone or in combination, and for example, light calcium carbonate, heavy calcium carbonate, kaolin, clay, talc, calcium sulfate, barium sulfate, Titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, synthetic silica,
White inorganic pigments such as aluminum hydroxide, alumina, lithopone, zeolite, magnesium carbonate, magnesium hydroxide, styrene plastic pigments, acrylic plastic pigments, polyethylene, microcapsules, organic pigments such as urea resin, melamine resin, etc. Can be mentioned.

As a method of producing the recording sheet of the present invention,
For example, pulp fibers are disintegrated into a slurry, and if necessary, a filler, a sizing agent, and other additives are added, papermaking is carried out by a paper machine and dried, or after papermaking, an aqueous solution of starch or a polymer substance is used. After size pressing, drying and machine calendering to obtain a support sheet, at least one or more ink receiving layers are provided using a coating device or size pressing device. The maximum heating temperature of the dryer is at least 100 ° C or higher, preferably 120 ° C or higher. It is preferable that the temperature is high in relation to the drying efficiency, but the temperature is not particularly limited. The machine calendar may or may not be used, but it is preferably used in consideration of workability in the next coating step. As a method for providing the A-side or B-side coating layer, either an on-machine coater or an off-machine coater may be used. For example, conventionally known air knife coaters, curtain coaters, die coaters, blade coaters, gate roll coaters, bar coaters, rod coaters, roll coaters, bill blade coaters, short dwell blade coaters and the like can be used. Further, after coating, finish using a calendar such as a machine calendar, super calendar, or soft calendar.

In the present invention, as other additives,
Dye fixing agent, pigment dispersant, thickener, fluidity improver, defoaming agent, foam suppressor, release agent, foaming agent, penetrant, coloring dye, coloring pigment, fluorescent whitening agent, ultraviolet absorber, An antioxidant, an antiseptic, an antifungal agent, a water resistance agent, a wet paper strength enhancer, a dry paper strength enhancer and the like can also be appropriately added.

[0023]

EXAMPLES Examples and comparative examples of the present invention will be described below, but the present invention is not limited to these examples. In addition, "parts" and "%" shown in the examples represent parts by weight and% by weight, unless otherwise specified.

Comparative Example 1 Using 100 g / m ² basis weight high quality paper as a base paper, 100 parts of synthetic amorphous silica (Fineseal X37B; manufactured by Tokuyama Soda) and polyvinyl alcohol (PVA11) were used for the ink receiving layer.
7; made by Kuraray Co., Ltd.) was mixed, the coating liquid concentration was adjusted to 15%, the ink receiving layer was coated and dried with an air knife coater so that the coating amount was 10 g / m ^2, and the linear pressure was 200 Kg /
cm was subjected to a super calender finish to obtain Comparative Example 1.

COMPARATIVE EXAMPLE 2 A high-quality paper having a basis weight of 70 g / m ² was used as a base paper, and 100 parts of synthetic amorphous silica (Cyroid 620; manufactured by Fuji Davisson) and polyvinyl alcohol (PVA 117; PVA 117;
(Kuraray Co., Ltd.) was mixed, the coating liquid concentration was adjusted to 23%, the ink receiving layer was coated and dried with an air knife coater so that the coating amount was 24 g / m ^2, and the linear pressure was 180 kg / c.
Comparative example 2 was obtained by super-calendering with m.

Comparative Example 3 On the back surface of the sheet of Comparative Example 1, 70 parts of hydrolyzed halloysite (Ina Kaolin; made by Ohshun Chemical Co., Ltd.), 30 delaminated kaolin clay (NU clay; made by Engelhard) 30
Part, styrene-butadiene copolymer latex (JSR0
693; made from Japan Synthetic Rubber) was mixed to adjust the coating liquid concentration to 30%, and the coating amount was 10 g with an air knife coater.
Comparative Example 3 was obtained by coating and drying the back surface coating layer so that the coating amount would be / m ² and performing supercalendering at a linear pressure of 200 Kg / cm.

Comparative Example 4 A back surface coating layer was applied to the back surface of the sheet of Comparative Example 2 in the same manner as in Comparative Example 3 and dried, and was supercalendered at a linear pressure of 180 kg / cm to give Comparative Example 4.

Comparative Example 5 Using a high quality paper having a basis weight of 35 g / m ² as a base paper, 100 parts of synthetic amorphous silica (Fineseal X37B; manufactured by Tokuyama Soda) and polyvinyl alcohol (PVA117;
(Kuraray Co., Ltd.) 40 parts was mixed, the coating solution concentration was adjusted to 15%, the ink receiving layer was coated and dried with an air knife coater to a coating amount of 10 g / m ^2, and the back side was humidified with fludex. A comparative example 5 was obtained by performing treatment such that the water content was 1.0% and drying, and performing super calendering at a linear pressure of 200 g / cm.

COMPARATIVE EXAMPLE 6 Except that a high-quality paper having a basis weight of 220 g / m ² was used as the base paper.
Comparative Example 6 was prepared in the same manner as Comparative Example 5.

Examples 1 to 3 On the back surface of the sheet of Comparative Example 1, the moisture content of the moisturizing treatment was 0.5.
%, 1.0%, and 1.5%, dried, and subjected to supercalendering at a linear pressure of 200 kg / cm to give Examples 1 to 3.

Example 4 A high-quality paper having a basis weight of 150 g / m ² was used as the base paper, except that
Example 4 was made in the same manner as Comparative Example 5.

Example 5 Using a high quality paper having a basis weight of 40 g / m ² as a base paper, 100 parts of synthetic amorphous silica (Fineseal X37B; manufactured by Tokuyama Soda) and polyvinyl alcohol (PVA117;
(Kuraray Co., Ltd.) 40 parts were mixed, the coating liquid concentration was adjusted to 15%, the ink receiving layer was coated and dried with an air knife coater so that the coating amount was 10 g / m ^2, and the moisture content on the back surface was humidified. Of 1.0%, then 100 parts of delaminated kaolin clay (NU clay; made by Engelhard) and styrene-butadiene copolymer latex (JSR0693; made by Japan Synthetic Rubber) 15 on the back surface.
Parts, and the coating solution concentration is adjusted to 30%, the back side coating layer is coated and dried with an air knife coater so that the coating amount is 10 g / m ^2, and the super calendar with a linear pressure of 180 Kg / cm. It was finished to obtain Example 5.

Example 6 Using 100 g / m ² basis weight high quality paper as a base paper, 100 parts of synthetic amorphous silica (Fineseal X37B; manufactured by Tokuyama Soda) and polyvinyl alcohol (PVA11) were used for the ink receiving layer.
7: made by Kuraray) 40 parts were mixed, the coating liquid concentration was adjusted to 15%, the ink receiving layer was coated and dried with an air knife coater so that the coating amount was 25 g / m ^2, and the back surface was humidified. Treatment is performed so that the water content is 1.5%, and then
Delaminated Kaolin clay (NU clay;
100 parts by Engelhard), styrene-butadiene copolymer latex (JSR0693; made by Japan Synthetic Rubber) 1
5 parts were mixed, the coating solution concentration was adjusted to 30%, the back side coating layer was coated and dried with an air knife coater so that the coating amount was 5 g / m ^2, and the super coat was applied at a linear pressure of 180 kg / cm. Rendering was performed to obtain Example 6.

Example 7 After coating and drying the ink-receiving layer of the sheet of Comparative Example 3, the back surface was treated so as to have a moisture content of 1.0%.

Example 8 Example 8 was carried out after coating and drying the ink-receiving layer of the sheet of Comparative Example 4 so that the moisture content on the back surface was adjusted to 1.5%.

Example 9 Using a high-quality paper having a basis weight of 100 g / m ² as a base paper, 70 parts of water-containing halloysite (Ina Kaolin; manufactured by Ohshun Chemical Co., Ltd.) and delaminated kaolin clay (NU clay; Engelhard) were provided on the back surface of the sheet. 30 parts by weight) and 15 parts by weight of styrene-butadiene copolymer latex (JSR0693; made by Japan Synthetic Rubber) are mixed and adjusted to a coating liquid concentration of 30% so that the coating amount is 10 g / m ² with an air knife coater. After coating and drying the back surface coating layer on the surface, 100 parts of synthetic amorphous silica (Fineseal X37B; manufactured by Tokuyama Soda) and polyvinyl alcohol (PVA117;
(Manufactured by Kuraray Co., Ltd.) 40 parts were mixed, the coating solution concentration was adjusted to 15%, the ink receiving layer was coated and dried with an air knife coater so that the coating amount was 10 g / m ^2, and the moisture content on the back surface was humidified. It is treated to 0.5% and dried, and the linear pressure is 20
Example 9 was made by supercalendering at 0 kg / cm.

Example 10 After applying and drying the ink-receiving layer of the sheet of Example 9, the back surface was treated so as to have a moisture content of 1.0%.

Examples 11 to 13 The procedure of Example 8 was repeated except that the coating amount of the back surface coating layer was set to 6 g / m ² , and after the coating of the ink receiving layer was dried, the moisture content on the back surface was 0. The treatments were carried out so as to obtain 0.5%, 1.0%, and 2.5%, and Examples 11 to 13 were made.

Table 1 shows the coating order, coating amount, and moistening water content, and Table 2 shows the measurement results of the above sheets.

[0040]

[Table 1]

[0041]

[Table 2]

In Table 2, A: Curl is 0 to 5 m in absolute value.
m: good, B: curl in absolute value of 5 to 10 mm, no practical problem, C: curl in absolute value of 10 mm or more, practically problematic.

As is clear from Comparative Examples 1, 2, 5, 6 and Examples 1 to 4, the basis weight of the support is in the range of 40 to 200 g / m ² , and the surface opposite to the ink receiving layer is subjected to a humidification treatment. The curling in a wide range of environments is improved by carrying out.

Further, from the results of Comparative Examples 3 and 4 and Examples 5 to 13, in the double-sided coated paper whose back surface is humidified after coating and drying the ink receiving layer, the ink receiving layer is irrespective of the coating order. If the coating amount ratio of the back coating layer is within a specific range, curling can be suppressed in a wide range of environments.

[0045]

INDUSTRIAL APPLICABILITY In the method for producing an ink jet recording sheet, ink is used in the process of producing an ink jet recording sheet having at least one ink receiving layer or a double coated ink jet recording sheet having a back surface coating layer on the opposite surface thereof. After the coating of the receiving layer is dried, the surface of the opposite side of 0.1 to the weight per 1 m ^{2 of} paper is transferred during the next process.
2. Curling in a wide range of environments can be suppressed by performing a humidification treatment of 5% by weight. Moreover, the curl does not run out of paper, and the product can be manufactured without problems in operation.

Claims (7)

[Claims] 1. In a manufacturing process of an ink jet recording sheet having at least one ink receiving layer provided on one surface (A surface) of a support, after coating and drying the A surface, the B surface is subjected to a humidification treatment. , The moisture content in the humidification treatment is 1 m ^{2 of} paper.
The method for producing an ink jet recording sheet is characterized in that it is in the range of 0.1 to 2.5% by weight based on the weight per unit. 2. A process for producing a double-sided coated ink jet recording sheet, wherein at least one or more ink receiving layers are provided on one surface (A surface) of a support and a back surface coating layer is provided on the opposite surface (B surface). In the above, after the coating and drying of the A side, the B side is subjected to a humidifying treatment during the next step, and the moisture content in the humidifying treatment is 0.1 to 2.5% by weight with respect to the weight per 1 m ^{2 of} paper. The method for producing an inkjet recording sheet is characterized in that 3. The method for producing an ink jet recording sheet according to claim 2, wherein the coating order of the recording sheet is to coat and dry the A side and then coat the B side. 4. The method for producing an ink jet recording sheet according to claim 3, wherein the recording sheet is coated on the B side and then dried on the A side. 5. The coating amount ratio of the A and B surfaces is A / B = 1/4.
The method for producing an inkjet recording sheet according to claim 2, 3 or 4, wherein the method is 4 to 1/1. 6. The basis weight of the support is 40 to 200 g / m ^2.
6. The method for producing an inkjet recording sheet according to claim 2, wherein the range is 3. 7. The ink jet recording sheet according to claim 2, wherein the A-side coating layer is mainly composed of a porous inorganic pigment, and the B-side coating layer is mainly composed of hydrohalloysite. Production method.