JPH0789220A - Production of cast coated paper for ink jet recording, cast coated paper and recording method using the same - Google Patents

Abstract

PURPOSE:To obtain cast coated paper for ink jet recording having especially excellent blank surface glossiness and excellent ink jet recording (printing) aptitude. CONSTITUTION:Cast coated paper is produced by applying a coating soln. containing a polymer with a glass transition point of 40 deg.C or higher obtained by polymerizing a monomer having an ethylenic unsaturated bond to raw paper having an undercoating layer containing pigment and an adhesive as principal components and provided thereto to form a cast coating layer and bringing the cast coating layer into contact with a heated mirror surface drum under pressure to dry the same.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cast coated paper for ink jet recording, and particularly to a method for producing a cast coated paper having an excellent white paper surface gloss and excellent ink jet recording (printing) suitability. The present invention relates to a cast coated paper and an inkjet recording method using the cast coated paper.

[0002]

2. Description of the Related Art In recent years, recording by an ink jet printer has been used in various fields because of its low noise, high speed recording, and easy multicoloring. As the ink jet recording paper, high-quality paper designed so as to have high ink absorbability, coated paper having a surface coated with a porous pigment, or the like is applied. By the way, all of these papers are mainly so-called matte ink jet recording papers having low surface gloss.

However, recently, with the expansion of applications such as high-speed ink jet recording, high definition of recorded images, and full-color ink jet recording, an ink jet recording paper having a high surface gloss and an excellent appearance has been desired. Generally, for paper with high surface gloss, apply a plate-like pigment on the surface,
Further, it is obtained by copying the mirror surface of the coated paper having a high gloss, which has been subjected to a calendering treatment, or a wet coating layer, by pressing and drying it on a heating drum surface having a mirror surface, if necessary. Cast coated paper and the like are known.

This cast coated paper has high surface gloss and more excellent surface smoothness as compared with a normal coated paper which has been subjected to a super calender finish, and an excellent printing effect can be obtained. However, when used as an ink jet recording sheet, it has various difficulties.

That is, a conventional cast coated paper is generally disclosed in, for example, US Pat. No. 5,275,846. A film-forming substance such as an adhesive in the pigment composition constituting the coating layer gives a high gloss by copying the mirror surface of the cast coater. On the other hand, the presence of the film-forming substance causes a problem that the coating layer loses its porosity and the ink absorption during ink jet recording is extremely reduced. In order to improve the ink absorbability, it is important to make the cast coating layer porous so that the ink can be easily absorbed, and for that purpose, it is necessary to reduce the amount of the film-forming substance. However, by reducing the amount of film-forming substance, the glossiness of white paper is reduced as a result.

As described above, at present, it is extremely difficult to satisfy both the surface gloss of cast coated paper and the suitability for ink jet recording (printing) at the same time.

[0007]

From the above, the inventors of the present invention have found a cast coated paper which maintains the high surface smoothness and high gloss originally possessed by the cast coated paper and is excellent in ink jet recording (printing) suitability. We have earnestly studied to obtain it. As a result, by applying a coating liquid for casting containing a polymer having a specific glass transition point on a base paper provided with an undercoat coating layer and performing a cast finish, extremely excellent inkjet printability In addition, it was found that a cast-coated paper that exhibits the excellent glossiness of inkjet-coated paper while maintaining the original high gloss of cast-coated paper and that has not been obtained with conventional cast-coated paper can be obtained. It was.

[0008]

The present invention includes, but is not limited to, the following embodiments.

[1] A polymer having a glass transition point of 40 ° C. or higher obtained by polymerizing a monomer having an ethylenically unsaturated bond is contained on a base paper provided with an undercoating layer containing a pigment and an adhesive. The coating liquid for coating is applied to form a coating layer for casting, and while the coating layer for casting is in a wet state, it is pressed against a heated mirror surface drum and dried to finish. Paper manufacturing method.

[2] The surface of the mirror drum surface is dried and finished under the temperature condition below the glass transition point of the polymer [1].
A method for producing the cast-coated paper for inkjet recording described.

[3] A polymer having a glass transition point of 40 ° C. or higher, which is obtained by polymerizing a monomer having an ethylenically unsaturated bond, on a base paper provided with an undercoat coating layer containing a pigment and an adhesive. An ink jet recording cast which is formed by applying a coating liquid to form a coating layer for casting, and while the coating layer for casting is in a wet state, is pressed against a heated mirror surface drum and dried to finish. Coated paper.

[4] The air permeability of the cast coated paper is (JI
SP-8117) 300 sec / 100 cc or less, The cast coated paper for inkjet recording according to [3].

[5] The cast coated paper for ink jet recording according to [3], wherein a cationic resin is contained in the undercoat coating layer.

[6] A polymer having a glass transition point of 40 ° C. or higher obtained by polymerizing a monomer having an ethylenically unsaturated bond is contained on a base paper provided with an undercoat coating layer containing a pigment and an adhesive. An ink jet recording method, characterized in that an image is formed by ejecting a water-based ink from fine pores on a strong glossy paper for ink jet recording having a surface coating layer. [7] The inkjet recording method according to [6], wherein thermal energy is applied to the water-based ink to eject the ink.

[8] The ink jet recording method according to [6], wherein the coated paper of the glossy paper has an air permeability of 300 sec / 100 cc or less.

[9] The inkjet recording method according to [6], wherein the undercoat coating layer of the glossy paper contains a cationic resin. [10] The inkjet recording method according to [6], wherein the surface coating layer of the glossy paper contains colloidal silica. [11] The inkjet recording method according to [6], wherein the undercoat coating layer of the glossy paper contains alumina or silica.

[0016]

As described above, in one embodiment of the present invention, a coating composition containing a specific resin having a specific glass transition point on a base paper provided with an undercoat coating layer containing a pigment and an adhesive. The object is to obtain a cast coated paper for inkjet recording, which has excellent surface gloss desired by the present invention and excellent aptitude for inkjet recording (printing) by coating and casting finish. .

Here, the cast coating liquid is obtained by polymerizing a monomer having an ethylenically unsaturated bond.
A coating composition containing a polymer having a glass transition point of not less than 0 ° C. is used.

That is, in the present invention, as a polymer obtained by polymerizing a monomer having an ethylenically unsaturated bond (hereinafter referred to as an ethylenic monomer) contained in a coating composition for casting (cast coating liquid), For example, methyl acrylate, ethyl acrylate butyl acrylate, 2
Ethylhexyl acrylate, lauryl acrylate,
Alkyl group such as 2-hydroxyethyl acrylate, glycidyl acrylate, etc. having 1 to 18 carbon atoms, alkyl group such as methyl methacrylate, ethyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, glycidyl methacrylate, etc. Of 1 to 18 methacrylic acid ester, styrene, α-methylstyrene, vinyltoluene, acrylonitrile, vinyl chloride, vinylidene chloride,
Vinyl acetate, vinyl propionate, acrylamide, N
A polymer obtained by polymerizing ethylenic monomers such as methylol acrylamide, ethylene and butadiene. Other monomers may be polymerized within the range that does not impair the effects of the present invention. Among the above, styrene-
Acrylic acid ester copolymers and styrene-methacrylic acid ester copolymers are preferred.

The polymer may be a copolymer in which two or more kinds of ethylenic monomers are used in combination, if necessary, and may be a substituted derivative of these polymers or copolymers. Incidentally, examples of the substituted derivative include, for example, those having a carboxyl group or those having an alkali reactivity. Further, the above-mentioned ethylenic monomer is polymerized in the presence of colloidal silica to obtain Si-
It is also possible to use it in the form of a complex by OR (R: polymer component) bond.

As mentioned above, the polymer obtained by polymerizing the above-mentioned ethylenic monomer is required to have a glass transition point of 40 ° C. or higher, more preferably about 50 ° C. to about 1 ° C.
It is preferably in the range of 00 ° C. Most preferably, it is about 70 ° C to about 90 ° C. The glass transition point can be adjusted by, for example, the type of ethylenic monomer or the degree of crosslinking of the polymer. For example, it is possible to raise the glass transition point by including 50% by weight or more of a monomer such as styrene which relatively raises the glass transition point. In the coating composition for casting, a pigment such as colloidal silica may be blended in addition to the above-mentioned polymer, and the amount thereof is usually about 0 parts by weight to about 200 parts by weight with respect to 100 parts by weight of the polymer. .

That is, in the conventional cast coated paper,
In order to obtain an excellent surface gloss, the resin content in the coating liquid was sufficiently formed into a film during the cast finish to obtain the cast gloss. However, such a method is not preferable because the porosity of the surface of the cast coated paper is reduced and, as a result, the absorption of ink during inkjet recording is reduced.
In the present invention, in order not to reduce the absorption of this ink,
Since a polymer having a high glass transition point is used, the polymer composition is cast-finished in a state where film formation does not occur completely. Therefore, the decrease in the porosity of the surface of the cast coated paper is slight, the absorption of the ink does not decrease, and a cast coated surface having an excellent glossy surface can be obtained. When the glass transition point of the polymer is lower than 40 ° C., the heat of the surface of the cast drum facilitates the film formation of the resin component more than necessary, the porosity of the surface of the cast coated paper is reduced, and the ink absorbency is reduced. Will fall.

In the present invention, the composition for cast coating layer can be obtained only by the polymer having the specific glass transition point as described above. The agent can be used in combination with casein, soybean protein and the like.
Further, a cationic resin containing a tertiary amino group or a quaternary ammonium group is used in combination for the purpose of improving ink fixability and water resistance after inkjet printing. In addition, pigments, dispersants, thickeners, defoamers, colorants, antistatic agents used for general printing coated papers and inkjet papers to adjust whiteness, viscosity, fluidity, etc. , Various auxiliaries such as preservatives are appropriately added.

Next, in the method of the present invention, the above-mentioned top coating solution (also referred to as a casting coating solution or a specific polymer composition) is preliminarily provided on a support (mainly base paper) on an undercoat coating layer. It is necessary to coat it. When the base paper is directly coated and cast-finished, the surface smoothness of the base paper is remarkably inferior to that of the undercoat, so that surface defects such as so-called pinholes occur. In another aspect of the invention, the cast coated paper J
The air permeability measured according to IS-P-8117 is 300.
Excellent ink absorbency is obtained by adjusting the time to not more than 100 sec / sec. If the air permeability measured according to JIS-P-8117 exceeds 300 seconds / 100 cc, the ink absorbency tends to decrease. The lower limit of the air permeability is not particularly limited, but usually about 5 seconds / 100 cc or more is preferable.
The air permeability is more preferably about 10 seconds / 100 cc to about 20.
It is 0 second / 100 cc.

After forming the cast coating layer, the air permeability according to JIS-P-8117 as described above is 300 seconds / 10.
One means for obtaining 0 cc of cast coated paper is a value measured by a Gurley high pressure type air permeability tester (ASTM-D-72) on the coated surface of the base paper after providing an undercoat coating layer.
6 B method), it may be adjusted to 30 seconds / 10 cc or less (the lower the value, the better the air permeability), preferably 20 seconds / 10 cc or less. By the way, 30 seconds / 10
If it exceeds cc, the ink absorbency of the inkjet tends to decrease, and the cast operability also decreases.

The pigment and adhesive contained in the undercoat coating layer will be described. That is, as the pigment, for example, kaolin,
Clay, calcined clay, amorphous silica, zinc oxide, aluminum oxide, aluminum hydroxide, calcium carbonate, satin white, aluminum silicate, smectite, magnesium silicate, magnesium carbonate, magnesium oxide,
Various publicly known pigments used in the general coated paper manufacturing field such as diatomaceous earth, styrene-based plastic pigments, urea resin-based plastic pigments, and benzoguanamine-based plastic pigments can be used.

Among the above pigments, it is particularly preferable to use a porous pigment such as amorphous silica or alumina because the ink absorbability during ink jet recording and the print color density are improved. The reason is that since amorphous silica and alumina have a very porous structure, a large amount of voids are obtained in the coating layer, and as a result, air permeability is lowered and ink absorption is improved.

Further, since this pigment has high transparency, it does not interfere with the color development of the ink dye absorbed in the coating layer, and as a result, the color development of the print is improved. Also,
The amount of porous pigment added is at least 50 as a pigment.
It is desirable that the content be at least wt%.

Next, as an adhesive for the undercoat layer, proteins such as casein, soybean protein and synthetic protein, various starches such as starch and oxidized starch, polyvinyl alcohol, cellulose derivatives such as carboxymethyl cellulose and methyl cellulose, Styrene-butadiene copolymer, methyl methacrylate-butadiene copolymer conjugated diene polymer latex, acrylic polymer latex, vinyl polymer latex such as ethylene-vinyl acetate copolymer, etc. Generally for coated paper The conventionally known adhesives used can be used alone or in combination. The amount of the adhesive compounded is 5 to 50% by weight, more preferably 10% by weight, based on the pigment.
It is adjusted in the range of ˜30% by weight.

In still another embodiment of the present invention, in the production of cast coated paper, the cast coated layer is formed at a temperature condition below the glass transition point of the polymer contained in the cast coating liquid (coating liquid for the overcoat layer). Drying of the gives good results. The lower limit of the mirror surface drum temperature is not particularly limited, but it is preferably about 40 ° C. or higher. More preferably, it is about 50 ° C to about 90 ° C. Support (base paper)
To provide a subbing layer, further to form a cast coating composition layer containing a polymer having the specific glass transition point, press-contacted to the cast drum, when cast finish,
It is particularly preferable to carry out the drying at a drum surface temperature below the glass transition point of the polymer. According to the above, by performing the cast finish in a state in which the polymer composition does not form a complete film, it is possible to obtain a cast coating layer surface having high gloss while maintaining the porosity of the cast coating layer surface. That is why.

On the contrary, when the drying temperature of the cast coating layer is increased, these polymers are formed at a temperature not lower than their glass transition point, and as a result, the porosity of the surface of the cast coating layer is increased by the polymer film. Since they are hindered, they tend to reduce the ink absorption during inkjet recording. Particularly, a drum surface temperature exceeding the glass transition point by 20 ° C. or more is not preferable.

By the way, when the glass transition point of the polymer is less than 40 ° C., the casting is finished at a surface temperature lower than that, and as a result, the drying speed of the cast coating composition is remarkably slowed and the productivity is lowered. Is inevitable.

Thus, the composition for the undercoat layer generally has a solid content concentration adjusted to about 1 to 65% by weight, and has a basis weight of about 2%.
² to 50 dry weight on base paper of 0 to 400 g / m 2
g / m ^2, more preferably a blade coater so that the order of 5 to 20 g / m ^2, an air knife coater, roll coater, brush coater, champflex coater, a bar coater, various known and used coated device such as a gravure coater Is coated and dried. Further, if necessary, smoothing treatment such as super calendering, brushing, and cast finishing can be performed after drying the undercoat layer.

The base paper to be the base is not particularly limited, and acid paper or neutral paper used for general coated paper is appropriately used. Further, the sizing degree and the filler can be appropriately adjusted according to the print quality. The coating surface of the thus obtained undercoat coated paper, a cast coating liquid consisting of the specific polymer composition described above, a blade coater, an air knife coater, a roll coater, a brush coater, a Chanplex coater, a bar coater, Coating with various known coating devices such as gravure coater,
As described above, while the coating layer is in the wet state, it is pressed against the heated mirror surface drum and dried to perform the cast finish. The coating amount of the cast coating liquid in this case is 0.2 to 30 g / m ² in terms of dry solid content, preferably 1 to 10
It is g / m ² .

In the cast coating liquid, pigments, dispersants, thickeners and defoaming agents used for general coated papers for printing and ink jet papers are used for controlling whiteness, viscosity, fluidity and the like. Various auxiliaries such as agents, colorants, antistatic agents and preservatives can be appropriately added.

Regarding conventional ink jet paper,
It is known to add a cationic resin to the coating layer for the purpose of improving the water resistance and the color density of printing. However, it is not preferable to add these cationic resins to conventional general cast coating liquids, because they lower the surface gloss and the ink absorbency. On the other hand, addition of a cationic resin to the undercoat coating layer coating liquid can improve water resistance and print color density without lowering surface gloss and ink absorbency. Furthermore, the addition of a cationic resin to the coating liquid for the undercoat layer means that when the coating composition for casting containing the above-mentioned polymer composition as a main component is coated as the top coating, the cationic resin is coated for casting. Since the aggregation of the composition is promoted, excessive penetration into the undercoat layer can be prevented, and as a result, a uniform and high-gloss cast coating surface with less uneven gloss and pinholes can be obtained.

The cationic resin in this case is, for example, a polyalkylene polyamine such as polyethylene polyamine or polypropylene polyamine, or a derivative thereof, an acrylic resin having a tertiary amino group or a quaternary ammonium group, a diacrylamine. Etc. are used.

Further, the addition amount of the cationic resin is adjusted in the range of 1 to 30 parts by weight, more preferably 5 to 20 parts by weight, relative to 100 parts by weight of the pigment. Other,
Dispersants, thickeners, used in the production of general coated paper,
Various auxiliaries such as defoaming agents, colorants, antistatic agents and preservatives are appropriately added.

The ink jet recording method of the present invention using the thus obtained cast coated paper for ink jet recording may be a system capable of effectively separating the ink from the nozzle to apply the ink to the recording medium as a range. Any method may be used, but in particular, in the method described in JP-A-54-59936, the ink subjected to the action of thermal energy undergoes a rapid volume change, and the action force due to this state change causes An inkjet recording method in which ink is ejected from nozzles can be effectively used.

An example of an inkjet recording apparatus suitable for the inkjet recording method of the present invention will be described below. An example of the head structure, which is the main part of the apparatus, is shown in FIGS. 1, 2 and 3. That is, the head 13 is made of glass, ceramic, plastic plate, or the like having a groove 14 through which ink passes, and a heating head 15 (a head is shown in the drawing, but not limited to this) used for thermal recording. It is obtained by bonding. The heating head 15 includes a protective film 16 made of silicon oxide or the like and aluminum electrodes 17-1 and 17.
-2, a heating resistor layer 18 made of nichrome or the like, a heat storage layer 19, and a substrate 20 having a good heat dissipation property such as alumina.

The ink 21 has a discharge orifice (fine hole) 2
2, the meniscus 23 is formed by the pressure P.

Now, when an electric signal is applied to the electrodes 17-1 and 17-2, the area indicated by n of the heating head 15 rapidly generates heat, and bubbles are generated in the ink 21 in contact therewith, and the pressure thereof is generated. At this point, the meniscus 23 is projected, the ink 21 is ejected, becomes a recording droplet 24 from the orifice 22, and flies toward the recording sheet 25. FIG. 3 shows an external view of a multi-head in which many heads shown in FIG. 1 are arranged. The multi-head includes a glass plate 27 having multi-grooves 26, and FIG.
The heating head 28 similar to that described in FIG.

FIG. 1 shows the head 1 along the ink flow path.
3 is a sectional view of FIG. 3, and FIG. 2 is a sectional view taken along the line AB of FIG. 1.

FIG. 4 shows an example of an ink jet recording apparatus incorporating such a head. In FIG. 4, 61
Is a blade serving as a wiping member, one end of which is held by a blade holding member to be a fixed end, which is in the form of a cantilever. The blade 61 is arranged at a position adjacent to the recording area by the recording head, and in the case of this example, is held in a form protruding in the movement path of the recording head. Reference numeral 62 denotes a cap, which is disposed at a home position adjacent to the blade 61, and has a configuration in which it moves in a direction perpendicular to the moving direction of the recording head and contacts the ejection port surface to perform capping. Further, 63 is an ink absorber provided adjacent to the blade 61, and is held in a form projecting in the movement path of the recording head like the blade 61. The blade 61, the cap 62, and the absorber 63 form an ejection recovery unit 64, and the blade 61 and the absorber 63 remove water, dust, and the like from the ink ejection port surface.

Reference numeral 65 denotes a recording head having ejection energy generating means for ejecting ink to a recording medium facing the ejection port surface where the ejection port is arranged for recording, and 66 a recording head 65 having the recording head 65 mounted thereon. It is a carriage for moving the. The carriage 66 slidably engages with a guide shaft 67, and a part of the carriage 66 is connected (not shown) to a belt 69 driven by a motor 68. Accordingly, the carriage 66 can move along the guide shaft 67, and the recording area by the recording head 65 and the area adjacent thereto can be moved.

Reference numeral 51 designates a paper feed section for inserting a recording medium, and 5
A paper feed roller 2 is driven by a motor (not shown). With these configurations, the recording medium is fed to a position facing the ejection opening surface of the recording head, and is ejected via the ejection roller 53 as the recording progresses.

In the above structure, when the recording head 65 returns to the home position after recording is completed, the head recovery unit 6
The fourth cap 62 is retracted from the movement path of the recording head 65, but the blade 61 is projected in the movement path. As a result, the ejection port surface of the recording head 65 is wiped. When the cap 62 comes into contact with the protruding surface of the recording head 65 to perform capping, the cap 62 moves so as to protrude into the movement path of the recording head.

When the recording head 65 moves from the home position to the recording start position, the cap 62 and the blade 61 are in the same positions as the above wiping positions. As a result, the protruding opening surface of the recording head 65 is wiped even during the movement.

The above-mentioned movement of the recording head to the home position is performed not only at the end of recording and at the time of ejection recovery, but also at the home adjacent to the recording area at a predetermined interval while the recording head moves in the recording area for recording. After moving to the position, the wiping is performed in accordance with the movement.

On the other hand, in the ink used in the ink jet recording method of the present invention, a dye for forming an image and a liquid medium for dissolving or dispersing the dye are essential components,
If necessary, various dispersants, surfactants, viscosity modifiers,
It is prepared by adding a specific resistance adjusting agent, a pH adjusting agent, an antifungal agent, a dissolution (or dispersion) stabilizer of a recording agent, and the like.

The recording agents used in the ink include direct dyes, acid dyes, basic dyes, reactive dyes, food dyes, disperse dyes, oil dyes and various pigments, but conventionally known ones are not particularly limited. Can be used without. The content of such a dye is determined depending on the type of liquid medium component, the properties required for the ink, etc., but in the case of the ink of the present invention, the formulation as in the conventional ink, that is, There is no particular problem when used in a proportion of about 0.1 to 20% by weight.

The ink used in the present invention is a liquid solvent prepared by dissolving or dispersing the above-mentioned dye, and is water or water and a water-soluble organic solvent, and a polyhydric alcohol having an ink drying preventing effect. What is contained is used.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.
Unless otherwise specified, parts and% in the examples represent parts by weight and% by weight, respectively. Unless stated otherwise, parts by weight refer to parts by weight of solids only, excluding water. The air permeability after forming the cast coating layer is measured according to JIS-P-8117,
Displayed in units of seconds / 100 cc. The air permeability of the base paper after forming the undercoat layer was measured by AS
Displayed in seconds / 10 cc according to the TM-D-726B method.

Example 1-1 100 parts of amorphous silica was used as a pigment, 20 parts of polyvinyl alcohol was used as an adhesive, and 4 parts was used as a cationic resin.
5 parts of acrylic resin containing primary ammonium salt and 0.5 part of sodium polyphosphate as a dispersant were added to give a solid content of 20.
% Coating solution for undercoating was prepared. 10 g / m ² dry weight of this base coating liquid on a base paper of 100 g / m ^2
2 was coated with an air knife coater and dried to obtain an undercoat base paper. The air permeability of this undercoat base paper was measured with a Gurley high pressure type air permeability tester and was 5 seconds / 10c.
It was c.

On the other hand, 100 parts of a styrene-2 methylhexyl acrylate copolymer having a glass transition point of 80 ° C. as a cast coating solution and 10 parts of calcium stearate as a releasing agent, a coating solution having a solid content concentration of 40%. Was prepared. This cast coating liquid was coated on the above base coating base paper using a roll coater, and immediately after the surface temperature was raised to 75
It was pressed against a mirror surface drum at ℃, dried, and then released to obtain a cast coated paper for inkjet recording. The cast coating amount at this time was 5 g / m ² in terms of solid content weight.

Example 1-2 As a cast coating liquid, a composite of a styrene-methyl acrylate copolymer having a glass transition point of 70 ° C. and colloidal silica (the weight ratio of the copolymer to the colloidal silica is 50: 5).
0) 100 parts, calcium stearate 1 as a release agent
A coating liquid having a solid content concentration of 0% of 40% was prepared.
This cast coating liquid was applied onto the undercoat base paper (base paper having an undercoat layer) of Example 1-1 by using a roll coater, and immediately thereafter, it was pressed against a mirror surface drum having a surface temperature of 60 ° C., dried, and then separated. The mold was cast to obtain a cast coated paper for inkjet recording. The cast coating amount at this time was ² g / m ² in terms of solid content weight.

Example 1-3 In Example 1-1, the surface temperature of the mirror surface drum was 50 ° C.
A cast coated paper for inkjet was obtained by the same method as in Example 1-1, except that.

Examples 1-4 As a cast coating liquid, a coating liquid having 100% of an acrylic ester polymer having a glass transition point of 45 ° C. and 5 parts of calcium stearate as a release agent and having a solid content of 40% was prepared. did. This coating liquid was coated on the same base paper as the base paper used in Example 1-1 by using a roll coater, and immediately thereafter, it was pressed against a mirror surface drum having a surface temperature of 40 ° C., dried, and then released. A cast coated paper for inkjet recording was obtained. The amount of cast coating at this time was 3 g / solid weight.
It was m ² .

Example 1-5 100 parts of a composite of a styrene-methyl acrylate copolymer having a glass transition point of 95 ° C. and colloidal silica as a cast coating liquid, and ammonium oleate 5 as a release agent
A coating liquid having a solid content concentration of 35% was prepared. This coating liquid was applied onto the same base paper as the base paper used in Example 1-1 by using a roll coater, immediately followed by pressure contact with a mirror surface drum having a surface temperature of 90 ° C., drying, and release. A cast coated paper for inkjet recording was obtained. At this time, the cast coating amount was 2 g / m ² in terms of solid content weight.

Example 1-6 40 parts of kaolin as a pigment, 30 parts of light calcium carbonate
Parts, and 30 parts of heavy calcium carbonate, 5 parts of starch as an adhesive, 10 parts of styrene-butadiene copolymer latex, 5 parts of a quaternary ammonium salt-containing acrylic resin as a cationic resin, and sodium polyphosphate as a dispersant. 0.5 part was added to prepare an undercoat coating liquid having a solid content concentration of 55%. This coating liquid was applied to a base paper having a basis weight of 60 g / m ² by a blade coater so as to have a dry weight of 20 g / m ² , and dried to obtain an undercoat base paper. The air permeability of this base paper was 50 seconds / 10 cc when measured with a Gurley high pressure type air permeability tester. On this undercoat base paper, the same cast coating liquid as used in Example 1-1 was used, and a cast coated paper for inkjet recording was obtained in the same manner as in Example 1-1.

Example 1-7 An ink jet recording cast coated paper was obtained in the same manner as in Example 1-1, except that the temperature of the mirror surface drum was changed to 90 ° C.

Example 1-8 An ink jet recording cast coated paper was obtained in the same manner as in Example 1-2, except that the temperature of the mirror surface drum was changed to 80 ° C.

Comparative Example 1-1 100 parts of a styrene-butadiene copolymer having a glass transition point of 0 ° C. as a cast coating liquid and 10 parts of calcium stearate as a release agent, a coating having a solid content concentration of 40%. A liquid was prepared. This cast coating liquid was used in Example 1-1.
After coating with a roll coater on the same undercoat base paper as above, immediately press the surface of the mirror drum with a surface temperature of 60 ℃,
After drying, the mold was released to obtain a cast coated paper for inkjet recording. At this time, the cast coating amount is 2 by solid weight.
It was g / m ² .

Comparative Example 1-2 As the pigment, 50 parts of kaolin and 50 parts of heavy calcium carbonate were used.
Parts, 5 parts of oxidized starch, 12 parts of styrene-butadiene copolymer latex as an adhesive, and 0.5 parts of sodium polyacrylate as a dispersant are added to prepare a coating liquid for undercoating having a solid content concentration of 60%. did. This coating liquid, 60 g / tsubo
As the base paper on the dry weight of m ² is 20 g / m ^2, coated with a blade coater and dried to obtain an undercoat base paper. The Gurley high pressure type air permeability tester for this undercoat base paper
It was seconds / 10 cc. On the other hand, as a cast coating liquid,
A coating liquid having a solid content concentration of 45% was prepared, which consisted of 100 parts of kaolin, 10 parts of casein, 10 parts of a styrene-butadiene copolymer (glass transition temperature 10 ° C.), and 10 parts of calcium stearate as a release agent. This cast coating liquid was applied onto the above-mentioned undercoat base paper using a roll coater, and immediately thereafter, it was pressed against a mirror surface drum having a surface temperature of 75 ° C.,
After drying, the mold was released to obtain a cast coated paper for inkjet recording. At this time, the cast coating amount was 1 by weight of the solid content.
It was 5 g / m ² .

Table 1 shows the results of the white gloss, the ink jet printer recording suitability and the operability of the cast coated paper thus obtained. The above evaluation was carried out by the following method.

[Glossiness of White Paper] It was measured according to JIS-P8142.

[Inkjet printer recording suitability / ink absorption] Color Image Jet I manufactured by Sharp Corporation
Printing was performed using O-735X (inkjet printer), and the drying property of the ink was visually evaluated. ⊚: There is no stain even if touched with a finger immediately after printing. ◯: Slightly soiled when touched with a finger immediately after printing, but almost dry. Δ: The ink portion is slightly shiny immediately after printing, but there is no problem in practical use. X: Ink is not practical because the ink flows during printing due to poor drying of the ink.

[Cast operability] ◯: Operation was possible without problems. Δ: The operation was performed at a low speed, but there was no practical problem. X: Drum pick occurs due to poor releasability.

[0067]

[Table 1]

Example 2-1 90 parts of amorphous silica as pigment, 1 light calcium carbonate
0 part, 20 parts of polyvinyl alcohol as an adhesive, 10 parts of dicyandiamide-based resin (trade name: Neofix FY / produced by Nika Chemical Industry Co., Ltd.) which is a condensate of dicyandiamide and formalin as a cationic resin, and a dispersant , 0.5 parts of sodium polyphosphate was added to give a solid content of 1
A 5% undercoat coating solution was prepared. 12 g / m ² dry weight of this undercoat coating liquid on 100 g / m ² of base paper.
² was coated with an air knife coater and dried to obtain an undercoat base paper. The air permeability measured by the Gurley high pressure type air permeability tester is 4 seconds / 10 cc.

On the other hand, the cast coating liquid comprises 40 parts of a styrene-2 methylhexyl acrylate copolymer having a glass transition point of 80 ° C., 60 parts of colloidal silica, and 2 parts of calcium stearate as a release agent, which has a solid content concentration of 30.
% Coating solution for casting was prepared. This coating liquid was coated on the above-mentioned undercoat base paper using a roll coater, immediately followed by pressure contact with a mirror surface drum having a surface temperature of 85 ° C., drying and release to obtain a cast coated paper for inkjet recording. It was The coating amount at this time was 5 g / m ² in terms of solid content weight. Air permeability of this cast coated paper (JIS-P-8
117) was 120 seconds / 100 cc.

Example 2-2 Ink jetting was carried out in the same manner as in Example 2-1 except that the surface temperature of the mirror surface drum was changed from 85 ° C. to 70 ° C. to obtain the cast coated paper in Example 2-1. A cast coated paper for recording was obtained. The cast coated paper had an air permeability of 80 seconds / 100 cc.

Example 2-3 100 parts of a styrene-methyl acrylate copolymer having a glass transition point of 50 ° C. as a cast coating liquid, and 5 parts of ammonium oleate as a releasing agent have a solid content concentration of 35.
% Coating solution for casting was prepared. This coating liquid was applied on the base paper for undercoat obtained in Example 2-1 using a roll coater, and immediately thereafter, it was pressed against a mirror surface drum having a surface temperature of 60 ° C., dried, and then released for inkjet recording. A cast coated paper was obtained. The coating amount at this time is 1 by weight of the solid content.
It was g / m ² . The air permeability of this cast coated paper is 1
It was 00 seconds / 100 cc.

Example 2-4 100 parts of a composite of a styrene-methyl acrylate copolymer having a glass transition point of 70 ° C. and colloidal silica as a cast coating liquid, and ammonium oleate 3 as a releasing agent.
A coating liquid for casting having a solid content concentration of 40% was prepared. This coating liquid was applied onto the base paper for undercoat obtained in Example 2-1 by using a roll coater, and immediately thereafter, it was pressed against a heating mirror surface drum having a surface temperature of 65 ° C., dried, and then released from the mold to form an inkjet. A cast coated paper for recording was obtained.
The coating amount at this time was 6 g / m ² in terms of solid content weight. The air permeability of this cast coated paper is 75 seconds / 100c
It was c.

Example 2-5 70 parts of MgCO ₃ as a pigment of an undercoating liquid, 30 parts of heavy calcium carbonate, 5 parts of oxidized starch as an adhesive, 10 parts of styrene-butadiene copolymer latex, and dicyandiamide as a cationic resin. And a formalin condensate dicyandiamide resin (trade name: Neofix F
Y / Nika Kagaku Kogyo Co., Ltd. 5 parts and 0.4 parts of sodium polyphosphate as a dispersant were added to prepare an undercoating coating liquid having a solid content concentration of 30%. This undercoat coating liquid
g / m as on the ^second base paper become 15 g / m ² by dry weight, coated with a blade coater and dried to obtain an undercoat base paper. The air permeability measured by the Gurley high pressure type air permeability tester is 10 seconds / 10 cc.

Then, Example 2-1 was formed on this base paper.
The cast coating liquid used in 1. was applied, and a cast coated paper for inkjet recording was obtained in the same manner as in Example 2-1. The air permeability of this cast coated paper is 220 seconds / 100
It was cc.

Examples 2-6 70 parts of Al ₂ O ₃ as a pigment of the undercoating liquid, 30 parts of amorphous silica, 5 parts of oxidized starch as an adhesive, 15 parts of polyvinyl alcohol, and a polyethylene polyamine type as a cationic resin. Resin (Brand name: Neofix RP-7
0 / Nippa Kagaku Kogyo Co., Ltd. 8 parts and 0.4 parts of sodium polyphosphate as a dispersant were added to prepare an undercoating coating liquid having a solid content concentration of 30%. This undercoat coating liquid
g / m ² of the base paper so that the dry weight becomes 9 g / m ² .
It was coated with a blade coater and dried to obtain an undercoat base paper.
Air permeability by Gurley high pressure type air permeability tester is 7 seconds / 10
It's cc. The base coating paper was coated with the coating liquid for casting used in Example 2-1, and a cast coated paper for inkjet recording was obtained in the same manner as in Example 2-1. The cast coated paper had an air permeability of 250 seconds / 100 cc.

Examples 2-7 80 parts of MgO and 2 kaolins as pigments for the undercoating liquid
0 part, polyvinyl alcohol 19 parts as an adhesive, diacrylamine acrylamide resin (trade name: Sumirez Resin 1001 / Sumitomo Chemical Co., Ltd.) 8 parts as a cationic resin, sodium polyphosphate 0.4 as a dispersant Parts were added to prepare an undercoat coating liquid having a solid content concentration of 30%. This coating liquid was applied onto a base paper having a basis weight of 80 g / m ² by a blade coater so as to have a dry weight of 14 g / m ^2, and dried to obtain an undercoat base paper. The air permeability measured by the Gurley high pressure type air permeability tester was 7 seconds / 10 cc. The base coating paper was coated with the coating liquid for casting used in Example 2-1, and a cast coated paper for inkjet recording was obtained in the same manner as in Example 2-1. The cast coated paper had an air permeability of 180 seconds / 100 cc.

Example 2-8 80 parts of aluminum oxide (alumina), amorphous silica 2
0 parts, polyvinyl alcohol 15 parts, sodium polyphosphate 1
Parts were added to prepare an undercoat coating liquid having a solid content concentration of 20%. This undercoating coating liquid was applied to a base paper having a basis weight of 100 g / m ^{2 with} a dry weight of 12 g / m ² by an air knife coater and dried to obtain an undercoat base paper. Air permeability by Gurley high pressure type air permeability tester is 15 seconds / 10c
c.

On the other hand, as a cast coating liquid, 50 parts of a styrene-2 methylhexyl acrylate copolymer having a glass transition point of 80 ° C., 50 parts of colloidal silica, and 2 parts of calcium stearate as a release agent have a solid content concentration of 30.
% Coating solution for casting was prepared. This coating liquid was coated on the above-mentioned undercoat base paper using a roll coater, immediately followed by pressure contact with a mirror surface drum having a surface temperature of 85 ° C., drying and release to obtain a cast coated paper for inkjet recording. It was The coating amount at this time was 6 g / m ² in terms of solid content weight. Air permeability of this cast coated paper (JIS-P-8
117) was 400 seconds / 100 cc.

Example 2-9 100 parts of amorphous silica as a pigment, 15 parts of polyvinyl alcohol as an adhesive, and 1.0 part of sodium polyphosphate as a dispersant were added to prepare an undercoating coating solution having a solid content of 15%. It was prepared. This undercoat coating liquid, 100 g / m 2
Such that the 6 g / m ² by dry weight to ² of the base paper, coated with an air knife coater and dried to obtain an undercoat base paper. Air permeability by Gurley high pressure type air permeability tester is 4 seconds / 10c
c.

On the other hand, as a cast coating liquid, 50 parts of styrene-2 methylhexyl acrylate copolymer having a glass transition point of 80 ° C., 50 parts of colloidal silica, and 2 parts of calcium stearate as a releasing agent have a solid content concentration of 30.
% Coating solution for casting was prepared. This coating liquid was coated on the above-mentioned undercoat base paper using a roll coater, immediately followed by pressure contact with a mirror surface drum having a surface temperature of 85 ° C., drying and release to obtain a cast coated paper for inkjet recording. It was The coating amount at this time was 6 g / m ² in terms of solid content weight. Air permeability of this cast coated paper (JIS-P-8
117) was 100 seconds / 100 cc.

Comparative Example 2-1 Styrene-2 having a glass transition point of 0 ° C. as a cast coating liquid
A coating liquid for casting having a solid content concentration of 35% was prepared, which was composed of 40 parts of methylhexyl acrylate copolymer, 60 parts of colloidal silica, and 5 parts of ammonium oleate as a release agent. This coating liquid was applied on the base paper for undercoat obtained in Example 2-1 using a roll coater, and immediately thereafter, it was pressed against a mirror surface drum having a surface temperature of 60 ° C., dried, and then released for inkjet recording. A cast coated paper was obtained. The coating amount at this time was 5 g / m ² in terms of solid content weight. The cast coated paper had an air permeability of 450 seconds / 100 cc.

Comparative Example 2-2 Styrene having a glass transition point of 30 ° C. as a cast coating liquid
A coating liquid for casting having a solid content concentration of 35% was prepared, which was composed of 100 parts of a butadiene copolymer and 5 parts of ammonium oleate as a release agent. After this coating liquid was coated on the base paper for undercoat obtained in Example 2-1, using a roll coater,
Immediately, it was pressed against a mirror surface drum having a surface temperature of 80 ° C., dried, and released to obtain a cast coated paper for inkjet recording. The coating amount at this time was 5 g / m ² in terms of solid content weight. The air permeability of this cast coated paper is 1300 seconds /
It was 100 cc.

COMPARATIVE EXAMPLE 2-3 Cast coating comprising 100 parts of a styrene-butadiene copolymer having a glass transition point of 0 ° C. as a cast coating liquid and 5 parts of ammonium oleate as a releasing agent and having a solid content of 35%. A liquid was prepared. This coating liquid was applied on the base paper for undercoat obtained in Example 2-1 using a roll coater, and immediately thereafter, it was pressed against a mirror surface drum having a surface temperature of 60 ° C., dried, and then released for inkjet recording. A cast coated paper was obtained. The coating amount at this time was 5 g / m ² in terms of solid content weight. The air permeability of this cast coated paper is 2200 seconds /
It was 100 cc.

Comparative Example 2-4 Kaolin 100 parts and casein 10 as a cast coating liquid
Part, styrene-methylmethacrylate (glass transition point 30 ° C.) 10 parts, and 10 parts of calcium stearate as a release agent, a coating liquid for casting having a solid content concentration of 45% was prepared. This coating liquid was applied onto the base paper for undercoat obtained in Example 2-1 by using a roll coater, and immediately thereafter, it was pressed against a mirror surface drum having a surface temperature of 75 ° C., dried, and then released for inkjet recording. A cast coated paper was obtained. The cast coating amount at this time was 15 g / m ² in terms of solid content weight. The air permeability of this cast coated paper is 5000 seconds /
It was 100 cc.

Comparative Example 2-5 As the pigment, 50 parts of kaolin and 50 parts of light calcium carbonate were used.
Parts, 5 parts of oxidized starch as an adhesive, 20 parts of styrene-butadiene copolymer latex, and 0.5 parts of sodium polyphosphate as a dispersant were added to prepare a coating liquid for undercoating having a solid content concentration of 50%. This undercoat coating liquid is 100 g / tsubo
As the base paper on the dry weight of m ² is 12 g / m ^2, coated with an air knife coater and dried to obtain an undercoat base paper. Gurley high pressure type air permeability tester has an air permeability of 200
It was seconds / 10 cc.

On the other hand, the casting coating liquid of Comparative Example 2-4 was applied onto the above-mentioned undercoat base paper using a roll coater, and immediately thereafter, it was pressed against a mirror surface drum having a surface temperature of 85 ° C. and dried, The mold was released to obtain a cast coated paper for inkjet recording. The coating amount at this time is 15% by weight of solid content.
It was g / m ² . The air permeability of this cast coated paper is 1
It was 0000 seconds / 100 cc.

The results of white gloss, ink jet recording suitability and operability of the cast coated paper thus obtained are summarized in Table 2. The above evaluation was carried out by the following method.

[Glossiness of White Paper] It was measured according to JIS-P8142.

[Inkjet Recording Suitability] (Absorbability of Inkjet Recording Ink) Printing was performed with Color Image Jet IO-735X (inkjet recording apparatus) manufactured by Sharp Corporation, and the drying property of the ink was visually evaluated. . ⊚: No stain at all when touched with a finger immediately after printing. ◯: Slightly soiled when touched with a finger immediately after printing, but almost dry. Δ: The ink portion is slightly shiny immediately after printing, but there is no problem in practical use. Δ ': The ink portion is shining immediately after printing, but it is dried after about 10 seconds, and there is no problem in practical use for a pattern with a small amount of ink. X: Due to poor drying of the ink, the ink flows during printing and cannot be used practically.

(Coloring property of ink jet recording ink after recording) Color Image Jet I manufactured by Sharp Corporation
Printing was performed with O-735X, and the density of the ink was visually evaluated. ◯: Color density is good. Δ: The color density is slightly low, but there is no practical problem. X: The color density is too low to be practical.

[Cast operability] ◯: Operation was possible without problems. △: Low speed but at a level at which operation is possible. ×: Drum pick occurs due to poor releasability and operation is impossible.

[0092]

[Table 2]

Inkjet printer (BJC-8) for ejecting ink by applying thermal energy to water-based ink
Ink jet recording was performed on the cast coated papers of Example 2-1 to Example 2-9 using 20J: trade name, manufactured by Canon Inc., and the same results as in Table 2 were obtained.

[0094]

As is clear from the results shown in Tables 1 and 2,
The cast coated paper of the present invention was excellent in surface gloss and suitability for inkjet recording, and could be efficiently produced.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a head portion of an inkjet recording apparatus.

FIG. 2 is a cross-sectional view of a head portion of an inkjet recording device.

3 is an external perspective view of a head in which the head shown in FIG.

FIG. 4 is a perspective view showing an example of an inkjet recording apparatus.

[Explanation of symbols]

 13: Head 14: Groove through which ink is passed 15: Heating head 16: Protective film 17-1: Aluminum electrode 17-2: Aluminum electrode 18: Heating resistor layer 19: Heat storage layer 20: Substrate 21: Ink 22: Orifice 23: Meniscus 24: Recording small droplet 25: Recording sheet 26: Multi-groove 27: Glass plate 28: Heating head 51: Paper feeding section 52: Paper feeding roller 53: Paper discharging roller 61: Blade 62: Cap 63: Ink absorber 64: Discharge recovery unit 65: Recording head 66: Carriage 67: Guide shaft 68: Motor 69: Belt

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiromasa Kondo 4-3-1, Jokoji, Amagasaki City, Hyogo Prefecture Shinko Paper Manufacturing Co., Ltd. Kanzaki Mill (72) Inventor Kazuhiro Nojima 4-chome, Jokoji Temple, Amagasaki City, Hyogo Prefecture No. 1 Shin-Oji Paper Co., Ltd. Kanzaki Mill (72) Inventor Katsuyoshi Imabefu 4-3-1, Jokoji, Amagasaki City, Hyogo Prefecture Shin-Oji Paper Mill Kanzaki Mill

Claims (14)

[Claims] 1. A polymer having a glass transition point of 40 ° C. or higher, which is obtained by polymerizing a monomer having an ethylenically unsaturated bond, on a base paper provided with an undercoat coating layer containing a pigment and an adhesive. A cast coated paper for ink jet recording, which is formed by applying a coating liquid to form a cast coating layer, and while the cast coating layer is in a wet state, press-contacts a heated mirror surface drum and finishes by drying. Manufacturing method. 2. The method for producing cast coated paper for ink-jet recording according to claim 1, wherein the mirror-finished drum surface is dried to a temperature below the glass transition point of the polymer. 3. The air permeability of the cast coated paper is defined by (JIS-P
-8117) 300 seconds / 100 cc or less, The manufacturing method of the cast coated paper for inkjet recording of Claim 1 or 2 characterized by the above-mentioned. 4. The method for producing a cast coated paper for ink jet recording according to claim 1, 2 or 3, wherein a cationic resin is contained in the undercoat coated layer. 5. A polymer having a glass transition point of 40 ° C. or higher, which is obtained by polymerizing a monomer having an ethylenically unsaturated bond, on a base paper provided with an undercoat coating layer containing a pigment and an adhesive. A cast coating for inkjet recording, which is formed by applying a coating liquid to form a coating layer for casting, and pressing and drying the coating layer for heating while the coating layer for casting is in a wet state and drying. Paper. 6. The air permeability of the cast coated paper is (JIS-P
-8117) 300 sec / 100 cc or less, The cast coated paper for inkjet recording according to claim 5. 7. The cast coated paper for ink jet recording according to claim 5, wherein a cationic resin is contained in the undercoat coated layer. 8. The cast coated paper for ink jet recording according to claim 5, 6, or 7, which is dried and finished with the temperature of the surface of the mirror surface drum being lower than the glass transition point of the polymer. 9. A polymer having a glass transition point of 40 ° C. or higher, which is obtained by polymerizing a monomer having an ethylenically unsaturated bond, on a base paper provided with an undercoat coating layer containing a pigment and an adhesive. An inkjet recording method, wherein an image is formed by ejecting a water-based ink from fine pores on a strong glossy paper for inkjet recording having a surface coating layer. 10. The ink jet recording method according to claim 9, wherein heat energy is applied to the water-based ink to eject the ink. 11. An air permeability of the coated paper of the glossy paper is 30.
The ink jet recording method according to claim 9, which is 0 second / 100 cc or less. 12. The ink jet recording method according to claim 9, wherein the undercoat coating layer of the glossy paper contains a cationic resin. 13. The ink jet recording method according to claim 9, wherein the surface coating layer of the glossy paper contains colloidal silica. 14. The ink jet recording method according to claim 9, wherein the undercoat coating layer of the glossy paper contains alumina or silica.