JP2001088434A - Ink jet recording medium - Google Patents

Abstract

(57) Abstract: An object of the present invention is to provide a corrugated cardboard ink jet recording medium which can be assembled into a corrugated paper box on which an original printing has been performed, and which has excellent suitability for an ink jet printer. An ink jet recording medium according to the present invention is an ink jet recording medium comprising at least one ink receiving layer provided on a support having two or more layers laminated, wherein at least one layer of the support is a cardboard. Is an ink jet recording medium.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording medium used for printing on paper containers utilizing an ink jet recording method. More specifically, the present invention relates to an ink jet recording medium provided with an ink receiving layer on the surface of a cardboard.

[0002]

2. Description of the Related Art In recent years, remarkable progress in ink jet printers and plotters has made it possible to easily obtain full-color and high-definition images.

In the ink jet recording system, fine droplets of ink are made to fly by various operating principles and adhere to a recording medium such as paper, thereby recording images and characters.
2. Description of the Related Art Ink jet printers and plotters have rapidly become widespread in various applications in recent years as hard copy creation devices for image information such as characters and various figures created by computers. In particular, a color image formed by a multi-color ink jet method can obtain a record comparable to multi-color printing by a plate making method or printing by a color photographic method, and is used in applications where the number of copies is small. Is widely used because it is cheaper than printing and photographic techniques.

In recent years, improvements and developments have been made in ink jet printers, and it has become possible to print even a recording medium having a thickness of several mm. Although generally used paper is often about 0.1 mm, there is also a demand for producing an original box or the like because it can print on a thick paper.

Japanese Patent Application Laid-Open No. 62-202781 discloses that
There is disclosed a recording material in which at least one side of a base material laminated with at least one layer is provided with ink receptivity. This has a basis weight of 1
A ^{20g / m 2 ~500g / m 2} , the case of obtaining the texture, such as a silver halide photographs and postcards, thick texture is intended to satisfy. However, it was somewhat unsatisfactory for use as a paper container.

[0006]

If the existing ink jet recording medium is used as it is for a paper box (box), the thickness is insufficient and the box cannot be used as a box. Therefore, the present inventors have made it possible to print original designs, photographs, etc. by giving ink jet suitability to the surface of the cardboard,
An object of the present invention is to provide an ink jet recording medium having sufficient strength as a box.

[0007]

That is, an ink jet recording medium according to the present invention is an ink jet recording medium comprising at least one ink-receiving layer provided on a support having two or more layers laminated thereon. Is a corrugated cardboard.

[0008] It is more preferable that the ink receiving layer is pressed against a heated mirror roll and dried to give a glossy finish while the ink receiving layer is in a wet state.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an ink jet recording medium of the present invention will be described in detail.

In one embodiment of the support having two or more layers as referred to in the present invention, an ink receiving layer is provided on one side of the first support, and cardboard is used as the second support on the other side of the support. It is manufactured by laminating. Here, as the first support provided with the ink receiving layer, generally, paper, paperboard,
Synthetic paper, resin-coated paper, film, synthetic resin plate, wood plate, metal plate, woven fabric, non-woven fabric and the like can be mentioned. In particular, paper such as paper and paperboard (postcard paper, white paperboard) can be suitably used in the present invention.

The cardboard laminated as the second support used in the present invention will be described. In the present invention, the term “corrugated cardboard” refers to one as described in Paper Sales Engineering Series 4 “Corrugated Cardboard” issued by Paper Industry Times. Corrugated cardboard is roughly divided into a liner to be pasted on the table and a midliner to be the paper to be corrugated. Liners are further divided into craft liners, jute liners, and interior liners, depending on the strength and the raw material used. Kraft liner is a liner made from kraft pulp as a main raw material and made into multiple layers, and is used for exterior. Recently, the number of craft liners containing waste paper has increased. The jute liner is a multilayer paper made from kraft pulp on the surface layer and waste paper as the middle and back layers, and includes a B liner, a C liner and the like. Jute liners are also used for exteriors like craft liners. The interior liner is used for a lightweight interior box, an individual packaging box, a partition, and a buffer, and does not particularly require strength.

[0012] Nakashin base paper used for the step (flute) in the corrugated cardboard includes pulp shin made from semi-chemical pulp (SCP) as a main material and special stuff made from waste paper. Most machines are made with fourdrinier or round net paper machines. Thick (1
(80 g, 200 g, etc.), and water-resistant shin with little deterioration in strength even when wet.

The corrugated cardboard is manufactured by a machine called corrugator, which forms corrugated cardboard into a sheet by corrugating a middle stiffener and gluing it to a liner on the front and back sides. There are single-sided corrugated cardboard, double-sided corrugated cardboard, double-sided corrugated cardboard, multiple double-sided corrugated cardboard, etc., in combination with middle shin and liner. The types of the steps (flutes) for forming the waveform are A, B, C,
The E flute is a typical example, and is defined by JIS according to the number of steps and the height of the steps. The E flute is not specified in JIS, but the number of steps is 95 ± 5/30 cm, and the step height is 1.1 to 1.8 mm.

As the lamination method, any conventionally known method can be suitably used. For example, starch, oxidized starch,
Starch derivatives such as cationized starch, etherified starch and phosphate esterified starch, carboxymethylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, cellulose derivatives such as cellulose sulfate, polyvinyl alcohol of various saponification degrees or silanol modified products thereof, carboxylated products, cations Derivatives such as chloride, casein, gelatin, denatured gelatin, natural polymers such as soy protein, water-soluble polymers such as polyvinylpyrrolidone, sodium polyacrylate, sodium salt of styrene-maleic anhydride copolymer, sodium polystyrene sulfonate Adhesives, acrylic resins, aqueous emulsion adhesives of non-water-soluble resins such as ethylene-vinyl acetate resin, nitrile rubber, chloroprene rubber, nitrocellulose, acrylic resin, butyral A method of laminating and bonding a corrugated cardboard to the back side of a first support provided with an ink receiving layer, using a solvent-based adhesive such as a fat or a polyester resin, and a thermoplastic resin hot melt such as a polyolefin or a polyester as an adhesive layer. It is.

There is also a method in which an adhesive layer is provided on the back side of the first support provided with the ink receiving layer, and laminated on a cardboard via the adhesive layer.

Further, there is also a method of manufacturing a corrugated cardboard having an ink receiving layer on the surface by manufacturing a corrugated cardboard with a corrugator using the first support provided with the ink receiving layer as a surface liner. In this case, the first support is advantageously a card paper having a certain thickness or a white paperboard. In the case of ordinary high-quality paper or the like, it is also possible to attach thick high-quality medium paper, card paper, white paperboard, liner base paper, or the like to the back side.

The card paper and white paperboard for the first support used in this embodiment are formed by laminating several layers. By combining various types of pulp, properties that do not exist in the papermaking paper are further imparted.
That is, high rigidity, bulky paper, strong strength, and the like.
In the case of paper having a large basis weight, the formation of a multilayer is easier to form than the formation of a single layer, and there is also an advantage that strength is obtained by improving the formation. It is also possible to use waste paper pulp or mechanical pulp for the middle layer.

As described above, multilayer papermaking is advantageous for paper having a high basis weight. However, in order to bond several sheets of paper to form a multilayer, mutual adhesion between layers is important. If the degree of adhesion between the layers is low, peeling between layers may be caused by stress during printing and processing. The inter-layer adhesion usually utilizes the entanglement of fibers and the adhesive force of chemicals. The chemicals use starch, polyacrylamide, etc., for example, give starch by spraying between layers with a wire part,
There is a method of gelatinizing by the heat of the dryer in the next step to obtain an adhesive strength.

White paperboard is roughly classified into two types, a manila ball and a white ball, depending on the raw materials to be machined, and there are coated products and uncoated products. Manila balls are further divided into high-grade paperboard, special paperboard, and general manila balls, each of which has a different raw material. High-grade paperboard is composed of ivory using 100% virgin pulp and card using mechanical pulp or waste paper pulp in the middle layer. Coated products are coated on the front and back. Often used. Special paperboard is a paper made by coating a single-sided coating liquid that does not use a fluorescent dye on the same base paper as high-grade paperboard, and is mostly used for high-quality paper containers (boxes for cosmetics, medicines, foods, etc.). Also,
General manila balls use mechanical pulp or waste paper pulp for the middle and back layers, and are used for general food boxes and the like. There are coated and uncoated products for white balls, but there are many coated white balls whose surfaces are coated using virgin pulp for the surface layer and waste paper pulp for the middle and back layers. Court white ball
It is used as a box (paper container) for foods, detergents, toys, tissues, etc.

Here, the functions required for the paper container will be described. Protection function; 2. Beautification / exhibition function; 3. Handling and transport functions Hygiene functions in the case of food are listed. The protection function protects the contents from dirt during the distribution channel and the exhibition period, prevents discoloration and deterioration of the contents due to sunlight, ultraviolet rays, indoor lighting and temperature, and alteration due to oxygen and bacteria in the air.・ In addition to preventing rot, it also protects against external impacts caused by transport handling. In addition, the beautification display function is an important function for white paperboard, which is an individual packaging material, in order to increase the customer's willingness to purchase. This requires printability that enables white and beautiful printing on the surface, and processability such as varnish and press coat for improving the display effect. Paperboard printing is moving toward more colors and higher grades in consideration of beautification and display effects.Especially for coated products, offset printing is replaced by gravure printing, which produces finer prints, and character / graphic printing is replaced by half-printing. It is rapidly changing to toned photo printing.

The ink jet recording medium of the present invention is an ink jet recording medium comprising at least one ink receiving layer provided on a support having two or more layers laminated, and at least one layer of the support is a cardboard.

As the ink receiving layer in the present invention, conventionally known constitutions of various ink receiving layers can be used.
That is, one configuration is a configuration in which an ink absorption layer mainly containing a porous pigment and an aqueous adhesive is provided.

Examples of the porous pigment of the present invention include porous synthetic amorphous silica, porous calcium carbonate, porous magnesium carbonate, and porous alumina (pseudo-boehmite, δ-alumina). High porous synthetic amorphous silica is preferred. Such a synthetic amorphous silica is a microporous, irregular fine particle having a three-dimensional structure of SiO2 formed by gelation of silicic acid, and has a pore diameter of 10%.
About 2000 Å.

As such synthetic amorphous silica, commercially available ones can be suitably used. For example, Mizukasil P-
526, Mizukacil P-801, Mizukasil NP-8,
Mizukacil P-802, Mizukasil P-802Y, Mizukasil C-212, Mizukacil P-73, Mizukacil P
-78A, Mizukacil P-78F, Mizukacil P-8
7, Mizukacil P-705, Mizukasil P-707, Mizukasil P-707D, Mizukasil P-709, Mizukasil C-402, Mizukasil C-484 (all manufactured by Mizusawa Chemical), Toksil U, Toksil UR, Toksil G
U, Toksil AL-1, Toksil GU-N, Toksil N, Toksil NR, Toksil PR, Solex, Fine Seal E-50, Fine Seal T-3
2, Fine Seal X-37, Fine Seal X-7
0, Fine Seal RX-70 Fine Seal A, Fine Seal B (all manufactured by Tokuyama), Carplex F
PS-101, carplex CS-7, carplex 80, carplex XR, carplex 67 (all manufactured by Shionogi & Co., Ltd.), thyroid 63, thyroid 6
5, thyroid 66, thyroid 77, thyroid 7
4, thyroid 79, thyroid 404, thyroid 6
20, thyroid 800, thyroid 150, thyroid 244, and thyroid 266 (all manufactured by Fuji Silysia Chemical Ltd.).

Examples of the aqueous adhesive of the present constitution include starch derivatives such as starch, oxidized starch, cationized starch, etherified starch, and phosphated starch, carboxymethylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, cellulose sulfate and the like. Cellulose derivatives, polyvinyl alcohol of various degrees of saponification or silanol modified products thereof, carboxylated products, various derivatives such as cationized products, casein, gelatin, modified gelatin, natural polymers such as soy protein, polyvinylpyrrolidone, sodium polyacrylate, styrene- Water-soluble synthetic polymers such as maleic anhydride copolymer sodium salt and polystyrene sodium sulfonate are used. Styrene-
Butadiene copolymer, conjugated diene copolymer latex such as methyl methacrylate-butadiene copolymer, acrylic polymer latex such as polymer or copolymer of acrylate and methacrylate, ethylene-
Vinyl-based polymer latex such as vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer, or functional group-modified polymer latex with functional group-containing monomer such as carboxy group of these polymers, polyurethane resin Thermosetting synthetic resins such as latex, melamine resin, and urea resin can be used.

The amount of the aqueous adhesive to be added to the porous inorganic pigment is 3 parts by weight based on 100 parts by weight of the total solid content of the pigment.
To 70 parts by weight, preferably 5 to 50 parts by weight,
If the amount is less than the weight part, the coating strength of the ink receiving layer is insufficient,
If the amount exceeds 70 parts by weight, the ink absorbency decreases.

Further, the ink absorbing layer contains, as an additive,
Dye fixing agents (various cationic resins), pigment dispersants, thickeners, flow improvers, defoamers, defoamers, release agents, sizing agents, penetrants, coloring dyes, coloring pigments, fluorescent whitening Agents, ultraviolet absorbers, antioxidants, preservatives, anti-binders, wet strength enhancers, dry strength enhancers, and the like can also be appropriately compounded.

In particular, a secondary amine which forms an insoluble salt with a sulfonic acid group, a carboxyl group, an amino group or the like in a water-soluble direct dye or a water-soluble acid dye which is a dye component of an aqueous ink,
When a cationic dye fixing agent comprising a quaternary amine and a quaternary ammonium salt is blended, the dye is captured in the ink absorbing layer, so that the color is improved. Further, the formation of the insoluble salt is preferable because the destruction of recording due to the dye or pigment in the ink flowing out of the ink absorbing layer due to the dripping or moisture absorption of water is suppressed.

In the present construction, if the amount of the ink absorbing layer applied is too small, not only does the ink absorbability become problematic, but also the image density, color and sharpness are low, and the ink is applied in the direction of the surface of the ink absorbing layer. The dot shape is deteriorated, called feathering, which is diffused and jagged like a bird. Also, if the coating amount is too large, the drying load in the drying step after coating increases, and not only does the productivity decrease due to the decrease in the coating speed, but also the coating composition constituting the ink absorbing layer when drying under a high load. The adhesive inside moves to the surface of the ink-absorbing layer together with the solvent that evaporates, and reduces the amount of voids on the surface. From such a viewpoint, the coating amount of the ink absorbing layer is preferably from 1 to 30 g / m ² . In addition, the ink absorbing layer can be applied in a certain application amount in several steps, and when applying gloss later, the gloss is improved as compared to applying the application amount at once.

The method of applying the ink-absorbing layer is as follows. Various apparatuses such as a blade coater, a roll coater, an air knife coater, a bar coater, a rod blade coater, a curtain coater, a short dwell coater, a size press and the like can be used on-machine or off-machine. Can be used. After the application, the ink-receiving layer can be formed by flattening and gloss-finishing using a calender such as a machine calender, a TG calender, a super calender, and a soft calender.

When the ink absorbing layer is applied, the ink absorbing layer may be provided on the support as it is, or a known surface activation treatment such as a corona treatment, a flame treatment, a plasma treatment, or an ultraviolet irradiation treatment may be performed. It can be applied later.

Another constitution of the ink receiving layer used in the present invention is to impart a gloss by applying a gloss developing layer comprising a coating composition containing a pigment and an adhesive as a main component on the ink absorbing layer. This is the obtained ink receiving layer.

As the pigment contained in the glossy layer, one or more known pigments can be used in order to improve the ink absorption and the color reproducibility of the ink. For example, light calcium carbonate, heavy calcium carbonate, magnesium carbonate, magnesium hydroxide, 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 amorphous silica, colloidal silica, alumina, colloidal alumina, pseudoboehmite, aluminum hydroxide, lithopone, zeolite, hydrohaloysite, inorganic pigments such as magnesium hydroxide, styrene-based plastic pigments, Organic pigments such as acrylic plastic pigments, polyethylene, microcapsules, urea resins, melamine resins, and the like. Among them, colloid particles having an average particle diameter of 300 nm or less are preferable.

The colloidal particles preferably applied to the glossy layer of the present invention preferably have a porous structure made of amorphous silica or alumina having an average particle diameter of 300 nm or less. The colloid particles are supplied in a suspended and dispersed form, and have a porous structure having a structure of secondary particles or more in which amorphous silica or alumina having a primary particle diameter of several nm or less, preferably 1 nm or less forms a network. is there. In the case of forming a glossy layer in combination with another pigment, 5 parts by weight, preferably 10 parts by weight or more of the colloid particles is used based on 100 parts by weight of the total pigment in the glossy layer. .

Further, in the colloid particles applied to the glossy layer of the present invention, cationic colloid particles are more preferable, and the cationic colloid particles are suspended and dispersed in water to form a colloid. The average particle diameter in the colloidal state measured by the dynamic light scattering method is 30.
0 nm or less and refers to particles whose particle surface is positively charged, for example, alumina sol such as boehmite or pseudo-boehmite, colloidal alumina, or JP-B-47-2695.
As disclosed in Japanese Patent Publication No. 9-109, there may be mentioned particles in which the surface of colloidal silica particles is coated with alumina.
If the average particle diameter exceeds 300 nm, the surface area of the colloidal particles decreases, so that the fixability of the ink decreases, and it becomes necessary to increase the coating amount of the glossy layer.

That is, when the charge on the particle surface is a cation, it becomes possible to fix the dye component in the ink on the glossy layer by electric interaction. Furthermore, since the colloid particles themselves do not have the capacity to absorb the solvent component, the solvent component penetrates the glossy layer,
It will penetrate the ink absorbing layer. If the penetration of the solvent component in the ink absorbing layer is slow, the ink will stay in the gloss developing layer and the ink will be diffused, so that the penetration of the solvent component must be fast.

Examples of the adhesive contained in the glossy layer include natural polymers such as casein, gelatin and soybean protein, starch derivatives such as etherified starch and phosphorylated ester, carboxycellulose and hydroxyethylcellulose. Natural derivatives such as cellulose derivatives such as cellulose derivatives thereof, and various derivatives such as polyvinyl alcohol or silanol modified products thereof, carboxyl modified products, cation modified products thereof having various degrees of saponification, polyethylene oxide, polyethylene glycol, polyacrylamide, polyvinyl pyrrolidone, etc. Water-soluble polymer, melamine resin, urea resin,
Various water-soluble synthetic polymers such as polyurea polyamide resins and derivatives thereof such as carboxyl-modified, amide-modified, and cation-modified, and styrene-butadiene-based, acrylate and methacrylate-based, ethylene-vinyl acetate-based, Examples include synthetic polymer emulsions such as polyurethanes, latexes and modified derivatives such as carboxyls, amides, and cations modified with various amine groups.

The mixing ratio of the adhesive in the glossy layer is as follows:
It is usually 5 to 70 parts by weight, preferably 5 to 50 parts by weight, based on 100 parts by weight of the pigment. If the mixing ratio of the adhesive to 100 parts by weight of the pigment is less than 5 parts by weight, the strength of the glossy layer may be insufficient. On the other hand, if the above mixing ratio is more than 70 parts by weight, the ink absorbency may be reduced and good image quality may not be obtained.

For coating the glossy layer, for example, various blade coaters, roll coaters, bar coaters, rod blade coaters, curtain coaters, short dwell coaters,
Various devices such as a size press can be used.

The amount of the glossy layer to be applied is different depending on the smoothness and size of the ink-absorbing layer, required smoothness and the like.
m ² or more is sufficient. A glossy layer is applied on the ink absorbing layer, and when dried, it already has a gloss, but it is possible to further impart a high gloss by a calendar process,
This treatment also does not require conditions at high linear pressure and high temperature, and does not reduce the voids in the coating layer so as to deteriorate the ink absorbency, so that an ink jet recording medium meeting the object of the present invention can be obtained. .

Another structure of the ink receiving layer used in the present invention is a polymer-based layer mainly containing at least one selected from a water-soluble polymer, a water-absorbing polymer and a water-swellable polymer. The ink receiving layer is provided as it is.

Many water-soluble polymers can be used alone or in combination in the ink-receiving layer containing a water-soluble or water-swellable polymer of the present structure. Examples of the water-soluble polymer include completely saponified or partially saponified polyvinyl alcohol, cationic modified, modified polyvinyl alcohol such as silanol modified, starch and modified starch, gelatin and modified gelatin, casein, pullulan, gum arabic, karaya gum, Examples include natural polymer resins such as albumin or derivatives thereof, water-soluble polymers such as polyacrylamide, polyvinylpyrrolidone, polyethyleneimine, polypropylene glycol, polyethylene glycol, maleic anhydride or a copolymer thereof, and the like. From the viewpoint of the fixability of N-
It is particularly preferable to include at least one of a water-soluble polymer having vinylpyrrolidone, polyvinyl alcohol, and gelatin.

Incidentally, gelatin is usually obtained by subjecting water-insoluble collagen obtained from animals, particularly pigskin, cowskin, cow bones or tendons as a raw material, to an alkali treatment or an acid treatment. The types include alkali-treated (lime-treated) gelatin, acid-treated gelatin, and gelatin extracted with high-pressure steam. There are also deionized gelatin obtained by ion-exchanging them, and low-molecular-weight gelatin decomposed by enzymes and the like. Furthermore, various other gelatin derivatives (for example,
Japanese Patent Publication Nos. 38-4854, 39-5514, 40-12237, 42-26345, U.S. Pat. Nos. 2,525,753 and 2,594,293. Book, No. 2,614,928
No. 2,763,639, No. 3,
Nos. 118,766, 3,132,945, 3,186,846, and 3,31
2,553, British Patent Nos. 861,414 and 1,033,189). As the gelatin used in the present invention, these known gelatins can be used alone or in combination, but the present invention is not limited to these.

Gelatin is an amphoteric electrolyte having an isoelectric point consisting of 18 kinds of amino acids. Thus, gelatin can be either cationic or anionic depending on the pH. That is, at a pH lower than the isoelectric point, the gelatin becomes cationic, and at a pH higher than the isoelectric point, the gelatin becomes anionic.

Since the acid-treated gelatin generally has a higher isoelectric point than the alkali-treated gelatin, it can be easily converted to the cationic type. Dyes or pigments used in inkjet inks are often anionic.
Therefore, if the gelatin of the ink receiving layer is a cationic type, a dye or a pigment can be chemically bonded.
Therefore, by using the acid-treated gelatin at a pH lower than the isoelectric point, the fixability of the dye or the pigment can be enhanced, and the recording by the dye or the pigment in the ink flowing out of the ink receiving layer due to water droplets or the like. Can be more effectively prevented.

The polyvinyl alcohol used in the present construction preferably has a saponification degree in the range of 86 to 100, more preferably 88 to 96. The polymerization degree is preferably in the range of 500 to 3500,
Those having a range of 0 to 2600 are more preferred. If these values are too small, it will be difficult to impart appropriate water resistance to the ink receiving layer. Conversely, if it is too large, the water swellability of the ink receiving layer becomes insufficient, and the ink absorbency and the fixability of the dye or pigment in the ink decrease.

The water-soluble polymer having N-vinylpyrrolidone as a structural unit used in the present structure has a molecular weight of 4
Those having a range of 10,000 to 1,000,000 are preferable, and those having a range of 400,000 to 800,000 are more preferable. When the molecular weight is less than 40,000, the strength of the ink receiving layer is insufficient. In addition, the molecular weight is 1
When the amount exceeds 100,000, the water swelling property of the ink receiving layer is insufficient, and the ink absorbency and the fixability of the dye or pigment in the ink are reduced.

These water-soluble polymers can be imparted with appropriate water resistance and water swellability by adding a crosslinking agent. Crosslinking agents include, for example, aldehyde compounds such as formaldehyde, glutaraldehyde, succinaldehyde, glyoxal and the like, US Pat. No. 3,28
No. 8,775, No. 2,732,303, British Patent No. 994,723, No. 1,16
No. 7,207, etc., compounds having a reactive halogen such as 2-hydroxy-4,6-dichloro-triazine salt, ketone compounds such as diacetylcyclopentanedione, divinyl sulfone ,
5-acetyl-1,3-diacryloyl, U.S. Pat. Nos. 3,635,718 and 2,232,763
Compounds having reactive olefins, such as those described in U.S. Pat.
Hydroxymethylphthalimide, US Patent No. 2,73
2,316, 2,586,168, etc., N-methylol compounds, U.S. Pat. No. 3,103,437, isocyanates, etc. Aziridine compounds described in U.S. Pat. Nos. 3,017,280 and 2,983,611; U.S. Pat. No. 2,725,294
Acid derivatives described in US Pat. No. 2,725,295 and the like, carbodiimide compounds described in US Pat. No. 3,100,704 and the like,
Epoxy compounds described in U.S. Pat. No. 3,091,537 and the like, U.S. Pat. No. 3,321,313
Nos. 3,543,292, etc., isoxazole compounds, halogenocarboxaldehydes such as mucochloric acid, dioxane derivatives such as dihydroxydioxane and dichlorodioxane, and others. Inorganic crosslinking agents such as blocked isocyanates, active acyl compounds, chromium alum, chromium trichloride and the like described in JP-A-53-113856. If necessary, these materials can be appropriately selected and used.

The rate of addition of the crosslinking agent to the water-soluble polymer is
It is preferably added in the range of 0.1% by weight to 10% by weight, and more preferably in the range of 0.2% by weight to 5% by weight. If the addition ratio of the crosslinking agent is less than 0.1% by weight, crosslinking is insufficient and water resistance is not sufficient, and if it exceeds 10% by weight, crosslinking proceeds too much to form a highly crosslinked film. In addition, the ink absorption amount of the ink receiving layer is extremely reduced, and an ink overflow phenomenon occurs in the solid printing portion.

The amount of the polymer constituting the ink receiving layer containing the water-soluble or water-swellable polymer is 0.5 g.
/ M ² or more, and preferably 2 g / m ² or more, from the viewpoint of ink fixability. When the amount is 0.5 g / m ² or less, sufficient ink fixability cannot be obtained.

If the amount of the polymer applied is too large, curling of the ink jet recording medium and peeling of the ink receiving layer from the support may occur. Therefore, the amount is preferably 30 g / m ² or less, more preferably 20 g / m ² or less. More preferred.

Further, the ink receiving layer of the present construction also includes other additives such as a dye fixing agent (various cationic resins), a pigment dispersant, a thickener, a flow improver, an antifoaming agent, a foam inhibitor, Release agents, sizing agents, penetrants, coloring dyes, coloring pigments, optical brighteners, ultraviolet absorbers, antioxidants, preservatives, anti-binders,
A wet-strength enhancer, a dry-strength enhancer, and the like can be appropriately added.

Still another structure of the ink receiving layer used in the present invention is that the above-mentioned pigment-containing ink-absorbing layer is formed on the above-mentioned pigment-containing ink-absorbing layer and the above-mentioned polymer mainly containing a water-soluble polymer as a gloss-generating layer. And an ink receiving layer.

According to this configuration, sufficient ink absorbency can be obtained by the ink absorbing layer containing the pigment, and appropriate gloss can be obtained by the gloss developing layer composed of the water-soluble polymer.

Further, the ink receiving layer or the gloss developing layer is coated and dried on the temporary support for surface formation, transferred and adhered to another support, and the temporary support is peeled off. An ink receiving layer having a surface on which the surface shape of the temporary support is copied can also be produced.

Furthermore, while the ink receiving layer is in a wet state, it can be a so-called cast treated ink receiving layer which is pressed against a heated mirror-finished roll and dried to finish.

As a method of casting the ink receiving layer, there are a direct method, a gelling method and a rewetting method. Among them, the direct method is to apply a high gloss finish by pressing the coating layer onto a heated mirror drum while the coating layer applied on the support is still wet. In the gelation method, while the coating layer applied on the support is still in a wet state, the coating layer is brought into contact with a gelling agent bath, and the gelled coating layer is pressed onto a heated mirror-surface drum surface. To perform a high gloss finish. Further, in the rewetting method, after once drying a wet coating layer, the coating layer is brought into contact with a rewetting liquid, and then the coating layer is pressed against a heated mirror drum to perform a high gloss finish. is there.

When the method of cast coated paper is adopted,
When any of the above three methods is selected, the moisture of the coating layer evaporates from the back surface of the support. Therefore, it is necessary to select a paper support having moisture permeability as the support.

With the above-described structure, a cardboard having an ink receiving layer suitable for ink jet recording can be manufactured. The corrugated cardboard for the interior and the cardboard for personal use have the functions of protecting, beautifying / displaying, and handling / transporting functions required for the above-mentioned paper box, and the proportion of the cardboard used is increasing. These paper containers are often subjected to printing, and the present invention can perform the printing by inkjet printing.

The present invention also includes an embodiment in which the ink receiving layers are provided on both sides. In this case, both sides may have the same configuration or one side may have a different configuration.

The inks of the present invention include the following colorants:
This is a recording liquid composed of a liquid medium and other additives.

Examples of the coloring agent include direct dyes, acid dyes, basic dyes, reactive dyes, and water-soluble dyes such as food colorants.

Examples of the solvent for the ink include water and various water-soluble organic solvents such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, and the like. Alkyl alcohols having 1 to 4 carbon atoms such as isobutyl alcohol; amides such as dimethylformamide and dimethylacetamide; ketones or ketone alcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane; polyethylene glycol and polypropylene glycol Polyalkylene glycols such as ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1,2,6-hexanetriol, thiodiglycol; Recall, hexylene glycol, an alkylene group such as diethylene glycol 2
And 6 alkylene glycols; lower alkyl ethers of polyhydric alcohols such as glycerin, ethylene glycol methyl ether, diethylene glycol methyl (or ethyl) ether, and triethylene glycol monomethyl ether. Among these many water-soluble organic solvents, polyhydric alcohols such as diethylene glycol, and lower alkyl ethers of polyhydric alcohols such as triethylene glycol monomethyl ether and triethylene glycol monoethyl ether are preferable.

As other additives, for example, a pH adjuster, a metal sequestering agent, an antioxidant, a fungicide, a viscosity adjuster, a surface tension adjuster, a wetting agent, a surfactant, a rust inhibitor and the like can be used. No.

[0065]

EXAMPLES The present invention will be described below in detail with reference to examples, but the contents of the present invention are not limited to these examples.
Further, “parts” and “%” shown in the examples are parts by weight and% by weight unless otherwise specified.

<Coating Liquid for Ink Absorbing Layer> The coating composition for the ink absorbing layer is a synthetic amorphous silica (Fine Seal X-3).
7B: 100 parts of Tokuyama Corporation, 30 parts of polyvinyl alcohol (PVA117: Kuraray), 30 parts of colloidal silica (Snowtex-O: Nissan Chemical Industries),
These were prepared by using 20 parts of a cationic dye fixing agent (Violet Resin 1001: manufactured by Sumitomo Chemical Co., Ltd.) at a solid content concentration of 15%.

<Coating Liquid A for Gloss-Producing Layer> The coating composition for the gloss-producing layer contains, as a pigment, colloidal particles having a particle diameter of 40 nm and a silica / alumina weight ratio of 75/25 (USB-
1: Catalyst Kasei Co., Ltd.) 100 parts, styrene-butadiene latex (0693: Nippon Synthetic Rubber Co., Ltd.) 5 parts as an adhesive, polycarboxylic acid thickener (Modecol V)
D: manufactured by San Nopco) with a solid content of 20 parts
These were prepared as%.

<Coating solution B for glossy layer> The coating composition for the glossy layer was 49 parts of gelatin (8% aqueous solution), 49 parts of polyvinylpyrrolidone K-30 (8% aqueous solution), and di-2-ethylhexyl sulfosuccinate. These were prepared as 2 parts of acid soda (1% aqueous solution).

Example 1 An ink-absorbing layer coating liquid was applied to a base paper having a basis weight of 83 g / m ² by an air knife coater to dryly apply 10 g / m 2.
^It was coated and dried on one side of the coated base paper so as to obtain ² . Then, the back surface of the paper provided with the ink receiving layer was laminated on a 2 mm thick double-faced cardboard with an aqueous adhesive (a vinyl acetate emulsion-based paste) and bonded to obtain an ink jet recording medium of Example 1.

Example 2 An ink-absorbing layer coating solution was applied to a base paper having a basis weight of 83 g / m ² by an air knife coater to dryly apply a coating amount of 10 g / m 2.
² is coated and dried on one side of the coated base paper, and then the chilled roll surface temperature is set to 50 ° C. and the linear pressure is set to 100 kg / h so that the coated surface of the ink receiving layer is in contact with the chilled roll surface.
Super calendar treatment was performed under the condition of cm. Then, the back surface of the paper provided with the ink receiving layer was laminated on a 2-mm thick double-faced cardboard with a solvent-based adhesive (a glue solution of styrene-butadiene synthetic rubber in normal hexane) and bonded together. I got

Example 3 An ink-absorbing layer coating liquid was applied on a base paper having a basis weight of 76 g / m ² by an air knife coater to a dry coating amount of 10 g / m 2.
^The coated base paper was coated on one side of the coated base paper and dried, and then a coating liquid A for glossy layer was applied and dried on the coated paper with an air knife coater to a dry coating amount of 6 g / m ² . Then, the back surface of the paper provided with the ink receiving layer was laminated and adhered to a 2 mm-thick double-faced cardboard with an aqueous adhesive (vinyl acetate emulsion paste) to obtain an ink jet recording medium of Example 3.

Example 4 An ink-absorbing layer coating solution was applied on a base paper having a basis weight of 76 g / m ² by an air knife coater to a dry coating amount of 10 g / m 2.
² and coated and dried on one side of the coated base paper, and then coated and dried with a gloss-generating layer coating solution A thereon using an air knife coater to a dry coating amount of 6 g / m ^2. The super calender treatment was performed under the conditions of a chill roll surface temperature of 50 ° C. and a linear pressure of 100 kg / cm so that the coated surface was in contact with the chill roll surface. Then, thickness 2mm
The ink-jet recording medium of Example 4 was obtained by laminating the back surface of the paper provided with the ink receiving layer on a double-faced cardboard with a solvent-based adhesive (a glue of styrene-butadiene synthetic rubber dissolved in normal hexane).

Example 5 An ink-absorbing layer coating solution was applied on a base paper having a basis weight of 76 g / m ² by an air knife coater to a dry coating amount of 10 g / m 2.
² was coated on one side of the coated base paper and dried, and then a coating liquid B for glossy layer was applied and dried thereon using an air knife coater to a dry coating amount of 3 g / m ² . Then, the back surface of the paper provided with the ink receiving layer was laminated and adhered to a 2 mm-thick double-faced cardboard with an aqueous adhesive (vinyl acetate emulsion paste) to obtain an ink jet recording medium of Example 5.

Example 6 An N-hyper having a basis weight of 260 g / m ² (manufactured by Mitsubishi Paper Industries, special white paperboard, eight-layer lamination using GP for the middle layer) was used as a support, and an ink absorbing layer was coated on its coated surface. The liquid was applied and dried using an air knife coater so as to have a dry coating amount of 10 g / m ^2, and then a coating liquid A for glossy layer was applied thereon with an air knife coater to apply a dry coating amount of 6 g / m ^2.
The chilled roll surface temperature was set to 50 so that the coated surface was in contact with the chilled roll surface.
Super calendar treatment was performed under the conditions of a temperature of 200 ° C. and a linear pressure of 200 kg / cm. Then use it as a surface liner, thickness 2
A single-sided corrugated cardboard was glued with starch glue using a glue machine to obtain an ink jet recording medium of Example 6.

Example 7 An ink-absorbing layer coating liquid was applied to a coated base paper having a basis weight of 83 g / m ² by an air knife coater to obtain a dry coating amount of 10 g / m 2.
² is coated on one side of the base paper, and after 2 seconds,
Casting was carried out by a direct method of pressing against a mirror roll heated to a surface temperature of 90 ° C. and drying. Then, thickness 2mm
The back surface of the paper provided with the ink receiving layer was laminated and bonded to a double-faced cardboard with an aqueous adhesive (vinyl acetate emulsion-based paste) to obtain a high gloss ink jet recording medium of Example 7.

Example 8 An ink-absorbing layer coating solution was applied to a base paper having a basis weight of 76 g / m ² by an air knife coater to dryly apply 8 g / m ^2.
Is coated on one side of the coated base paper and dried, and then a gloss developing layer coating solution A is coated thereon with an air knife coater to a dry coating amount of 4 g / m ^2, and after 2 seconds, It was treated by a direct method of pressing against a mirror roll heated to a surface temperature of 90 ° C. and drying. Then, the back surface of the paper provided with the ink receiving layer was laminated and adhered to a 2-mm-thick double-faced corrugated cardboard with an aqueous adhesive (vinyl acetate emulsion paste) to obtain a high gloss ink jet recording medium of Example 8. Was.

Example 9 An ink-absorbing layer coating liquid was applied to a base paper having a basis weight of 76 g / m ² by an air knife coater to dryly apply 8 g / m ^2.
Is applied and dried on one side of the coated base paper, and then a gloss developing layer coating solution A is applied thereon by an air knife coater to a dry coating amount of 4 g / m ² and dried to receive ink. A layer was formed. Next, water was applied to the ink-receiving layer to re-wet the ink-receiving layer, and the ink-receiving layer was cast by a rewetting method in which the ink-receiving layer was pressed against a mirror roll heated to a surface temperature of 90 ° C. and dried. Then, the back surface of the paper provided with the ink receiving layer was laminated and adhered to a double-sided cardboard having a thickness of 2 mm with an aqueous adhesive (vinyl acetate emulsion paste) to obtain a high gloss ink jet recording medium of Example 9. Was.

Example 10 An N-pearl deluxe having a basis weight of 210 g / m ² (manufactured by Mitsubishi Paper Mills, a special white paperboard coated on one side) was used as a support, and the coating surface of the ink-absorbing layer was coated on the coated surface with an air knife coater. Coating and drying to a dry coating amount of 8 g / m ² ,
Next, the glossy layer coating solution A was coated thereon by an air knife coater to a dry coating amount of 4 g / m ² and dried to form an ink receiving layer. Next, water was applied to the ink receiving layer to re-wet the ink receiving layer, and immediately thereafter, the ink receiving layer was cast by a rewetting method of pressing against a mirror-surface roll heated to a surface temperature of 90 ° C. and drying. Then, using this as a surface liner, a glue machine was used to attach starch glue to a single-sided cardboard having a thickness of 2 mm using a glue machine to obtain a high gloss ink jet recording medium of Example 10.

Comparative Examples 1 to 10 Ink jet recording media of Comparative Examples 1 to 10 were obtained in the same manner as in Examples 1 to 10, except that lamination on cardboard was not performed.

The evaluations of Examples 1 to 10 and Comparative Examples 1 to 10 were performed by the following methods, and the results are shown in Table 1.
The measurement and evaluation were performed under the environment specified in JIS-P8111.

1) Ink Absorption The ink absorption was evaluated by printing a heavy-colored square pattern with cyan ink and magenta ink using BJC-420J manufactured by Canon Inc. which is an ink jet recording apparatus.
The boundary between the printed pattern and the unprinted portion was visually evaluated according to the following criteria. ：: No bleeding was observed at the boundary portion ：: Little bleeding was observed at the boundary portion ：: Bleeding was detected at the boundary portion ×: Remarkable bleeding was observed at the boundary portion Good ink absorption Shown are the evaluations of ◎ to ○.

2) Evaluation of practicality Each recording medium was assembled in a box shape, and the touch, the strength as a box, and the like were instinctively evaluated. In the evaluations, ○ indicates that there is no practical problem, and X indicates that it lacks practicality.

[0083]

[Table 1]

According to Table 1, an ink receiving layer was provided on the support,
Examples 1 to 10 laminated with cardboard are useful as ink-jet printable cardboard. Comparative Examples 1 to 10
Is not a laminated support and lacks practicality.

[0085]

As described above, by implementing the present invention, it is possible to provide an ink jet recording medium suitable for printing on corrugated paperboard and suitable for ink jet printing. Even when used in a cardboard box (box) on which an original print is applied, a glossy one subjected to a cast treatment can provide a high-quality practical ink jet recording medium with a better appearance.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C056 FC06 2H086 BA15 BA21 4F100 AK22G AT00A AT00B BA03 BA10A BA10C DD12A DG10A EC01 EJ19 EJ42 EJ86 GB90 JD14C JM01G JN21

Claims (2)

[Claims] 1. An ink jet recording medium comprising at least one ink receiving layer provided on a support having two or more layers laminated thereon, wherein at least one layer of the support is a cardboard. 2. While the ink receiving layer is in a wet state,
2. The ink jet recording medium according to claim 1, wherein the medium is pressed against a heated mirror-finished roll, dried, and gloss-finished.