JPH1067905A - Curable composition, recording medium and production thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a curable composition capable of easily forming an ink receiving layer having a high water resistant fastness, while satisfying various characteristics for the ink receiving layer such as a high ink absorption and a rapid absorption rate for enabling the development of an ink jet recording method into an industrial field, and a recording medium formed by using the same and to provide a method for producing the same medium. SOLUTION: This curable composition contains a component (A) consisting of a hydrophilic resin having ethylenically unsaturated groups in side chain thereof in a range of (m)=0.1-2.O, when a concentration of unsaturated bonding is expressed by number of mols (m) of the ethylenically unsaturated bonds per 1kg resin, and a component (B) consisting of a hydrophilic oligomer having 2-4 ethylenically unsaturated groups at the terminals of' molecule thereof, and having 400-3000 weight averaged molecular weight. This recording medium is produced by using the above composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a curable composition, a recording medium and a method for producing the same, and more particularly, to a curable composition used as a coating material capable of forming an excellent ink receiving layer. That is, by using the curable composition, a crosslinked structure is provided in the ink receiving layer, and not only an OHP film but also printability using an aqueous ink is provided, and high robustness which can be used in the industrial field. The present invention relates to a curable composition, a recording medium, and a method for producing the same, which are useful as a material for forming an ink-receiving layer having:

[0002]

2. Description of the Related Art In recent years, the ink jet recording system has made a remarkable development in the digital recording system, and has become widespread particularly as an output device of a personal computer used in an office. Furthermore, taking advantage of the ink-jet method that can be easily printed without a plate,
The expansion into the industrial field is also becoming active. However, compared to office use, which mainly focused on printing on paper, in the industrial field, recording materials to be printed are various, such as metal plates, plastics, rubber, ceramics, cloth, leather, glass, food, etc. is there.

[0003] Most of the ink jet printers currently in widespread use a so-called bubble jet method utilizing thermal energy, and generally, water-based ink is used in this method. For this reason, when printing on a recording material that does not absorb ink such as a metal plate or plastic, it is necessary to provide an ink receiving layer on these recording materials. In office use as well, printing on non-absorbable materials such as OHP films has been performed, and there have been many proposals for ink receiving layers. However, when considering the development in the industrial field, in addition to the performance requirements on images described in the following (1) to (3), which have been considered as problems in office use, the following (4) to (4) 6)
In addition, the performance described in (1) is further required. (1) High ink absorption capacity (large ink absorption capacity and fast ink absorption time) (2) High optical density of dots and no blur around dots (3) Clear and high resolution image (4) High robustness (particularly water resistance) (5) High adhesion to substrate (6) Ink receiving layer can be formed easily in a short time It has been proposed to form an ink receiving layer using a cured polymer material. Among them, the use of the active energy ray-curable resin is considered to be an effective means for achieving the above-mentioned various requirements since the ink receiving layer can be easily formed in a short time.

Conventionally, it has been proposed to use a resin cured by an active energy ray for the ink receiving layer, thereby further improving the robustness such as water resistance while maintaining the characteristics such as the absorption performance of the ink receiving layer. There are many. For example, JP-A-62-94379 and JP-A-62-94379
JP-A-94380 proposes an ink receiving layer in which a crosslinked structure portion and a non-crosslinked structure portion are formed by a resin composition comprising a resin having photopolymerizability and a resin having no polymerizability. However, even in such a case, the printing speed is increased, and the ink application amount per unit area is increasing with the increase in the resolution, and the ink suitable for the performance is used for the current inkjet color printer. It is difficult to form an ink-receiving layer having more water resistance while maintaining the absorption capacity and the ink absorption speed.

Japanese Patent Application Laid-Open No. 62-221591 discloses a coating layer mainly composed of an ultraviolet-cured anionic acrylic copolymer and a coating layer mainly composed of an ultraviolet-cured cationic acrylic copolymer. An ink receiving layer comprising a coating layer is proposed. According to the publication, the ink receiving layer can be formed by using an ion complex present at the boundary between two layers composed of two kinds of electrolyte polymers having different anionic and cationic properties or at the diffusion layer of the two layers. Has water resistance. That is, according to such a polyion complex, the medium and the dye molecules are present in the strong interaction (attraction) between the localized ions of anions and cations present in various parts of the layer. As a result, the movement of both the medium molecules and the dye molecules is strongly suppressed, so that the apparent fixability and water resistance are improved. However, the true drying of the media, on the other hand, is very slow, and has a significant drawback in terms of fixability in practice.

Further, Japanese Patent Application Laid-Open Nos. 1-222985 and 2-1360 propose an ink receiving layer obtained by curing a prepolymer having photocurable groups at both ends. However, in the case of this method, when the molecular weight of the prepolymer is small, there is a drawback that the ink absorption cannot be maintained even if the water resistance is good, as described above. Conversely, if the molecular weight is large, it is thought that a structure similar to the present invention can be created, but in this case, the reaction between both ends of the high molecular weight substance is difficult, and it is substantially difficult to cure. I think that the. As described above, in the range of the related art, the printing speed is increased, and the ink application amount per unit area is increasing with the increase in resolution. There is no known material for forming an ink-receiving layer having higher waterfastness while maintaining the water-repellency.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an ink jet recording system which has been conventionally required for an ink receiving layer, as described above, so that the ink jet recording system can be developed in the industrial field. A curable composition that satisfies various performances such as high absorbency and high absorption rate, and is further capable of easily forming an ink receiving layer and obtaining an ink receiving layer having high water fastness. It is an object of the present invention to provide a recording medium formed by the above method and a method for manufacturing the same.

[0008]

The above object is achieved by the present invention described below. That is, the present invention is a curable composition comprising the following components A and B. <Component A> When the unsaturated bond concentration is represented by the number m of moles of ethylenically unsaturated bonds in 1 kg of the resin, when the ethylenically unsaturated group is a side chain, m is in the range of 0.1 to 2.0. <Component B> Hydrophilic oligomer having a weight average molecular weight of 400 to 3,000 having 2 to 4 ethylenically unsaturated groups at molecular terminals

The present inventors have conducted intensive studies on the above-mentioned problems of the prior art, and as a result, by forming an ink receiving layer using a mixture of the above-mentioned A component and B component, the ink absorbing property, It has been found that an ink receiving layer having both water resistance can be formed. In particular, after the curable composition of the present invention composed of a mixture of the above-mentioned component A and component B is applied to a substrate, the composition is cured with an active energy ray to form an ink receiving layer, thereby having a crosslinked structure. An ink-receiving layer was obtained, and it was found that this structure enables formation of an ink-receiving layer having more water-fastness without impairing the ink absorption. That is, the hydrophilic resin used as the component A is a resin that forms the skeleton of the ink receiving layer. By mixing the hydrophilic oligomer that is the component B with the hydrophilic resin, the hydrophilic resin of the component A is crosslinked to form an ink receiving layer. Make the layers water resistant.

[0010]

Next, the present invention will be described in more detail with reference to embodiments of the present invention. The curable composition of the present invention is characterized by containing the following components A and B. Hereinafter, these components A and B will be described. <Component A> When the unsaturated bond concentration is represented by the number m of moles of ethylenically unsaturated bonds in 1 kg of the resin, when the ethylenically unsaturated group is a side chain, m is in the range of 0.1 to 2.0. <Component B> Hydrophilic oligomer having a weight average molecular weight of 400 to 3,000 having 2 to 4 ethylenically unsaturated groups at molecular terminals

First, the component A will be described. The hydrophilic resin of component A, which is a constituent material of the curable composition of the present invention,
When the ink receiving layer is formed, it is a resin that forms the skeleton thereof, and therefore needs to have properties such as ink absorbency and film formability so that it can function as the ink receiving layer. In general, since ink used in an ink jet printer is aqueous, it is preferable to use a hydrophilic resin having good film-forming properties as the component A. Furthermore,
In order to impart water resistance to the ink receiving layer, a material having an ethylenically unsaturated group in a side chain is used so that the ink receiving layer can be crosslinked by active energy rays or the like to form a crosslinked structure in the ink receiving layer. Specifically, 1 kg of a resin having an ethylenically unsaturated group introduced into a side chain of a hydrophilic and film-forming resin.
When the unsaturated bond concentration is represented by the number of moles of ethylenically unsaturated bond m in the above, the ethylenically unsaturated group is added to the side chain and m =
A hydrophilic resin having a range of 0.1 to 2.0 is used.

The following methods (1) to (5) can be used to obtain a hydrophilic resin, which is the component A used in the present invention, in which an ethylenically unsaturated group is introduced into the hydrophilic resin in an effective range. Is mentioned. (1) For a hydrophilic resin having a hydroxyl group, a method utilizing the following reaction is suitable. Reaction of adding half urethane compound of acryloyl compound to hydroxyl group After esterification of unsaturated acid anhydride with hydroxyl group, esterification reaction with glycidyl (meth) acrylate Condensation reaction of N-alkylol (meth) acrylamide with hydroxyl group (2 For the hydrophilic resin having an epoxy group, a method utilizing the following reaction is preferable. Esterification reaction between acrylic acid and epoxy group (3) For a hydrophilic resin having a carboxyl group, a method utilizing the following reaction is suitable. Esterification reaction between glycidyl (meth) acrylate and carboxyl group (4) For a hydrophilic resin having an amino group, a method utilizing the following reaction is suitable. Ring-opening addition reaction between glycidyl (meth) acrylate and an amino group Reaction for adding a half urethane compound of an acryloyl compound to an amino group (5) A method based on a combination of the above methods (1) to (4) is preferable.

According to the above-mentioned methods (1) to (5), an ethylenically unsaturated group can be introduced into the side chain of the hydrophilic resin, but the hydrophilic resin serving as the skeleton has ink absorbency. Further, any conventionally known hydrophilic resin that is generally used can be used as long as it has a film-forming property. Examples of such a device include the following. 1) As a resin having a hydroxyl group, the following can be used.・ Polyvinyl alcohol and modified products thereof (cation modified product, anion modified product, acetalized product, etc.) ・ Cellulose such as hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose, etc. ・ Albumin, gelatin, casein, starch, cationized starch, gum arabic , A natural resin such as sodium alginate, a copolymer of a monomer having a hydroxyl group and a hydrophilic monomer

More specifically, for example, the following materials can be used. For example, as polyvinyl alcohol, gohsenol (trade name, manufactured by Nippon Gosei),
Shin-Etsu Poval (trade name Shin-Etsu Chemical), Electrified PVA (trade name Electrochemical), Kuraray PVA (trade name Kuraray), Unitika Poval (trade name Unitika), etc. Made)
Examples of polyvinyl acetal dimethylaminoacetate include AEA (trade name manufactured by Sankyo) and the like. Examples of hydroxypropyl cellulose include Nisso HPC (trade name manufactured by Nippon Soda), Shin-Etsu HPC (trade name manufactured by Shin-Etsu Chemical), and hydroxypropyl methyl cellulose. The Metros 90S
H, Metrolose 65SH, Metrolose 60SH (trade name of Shin-Etsu Chemical Co., Ltd.), etc., as the hydroxyethyl cellulose, NATROSOL (Aqualon), Fuji Chem HE
C (trade name: Fuji Chemical), Arabic gum: Arabic gum HP (trade name, manufactured by Sanei Pharmaceutical Trading Co., Ltd.), etc. , Kimitsu Algin (trade name, Kimitsu Chemical), Tack Algin (trade name, Kibun Food Chemifa), propylene glycol alginate, Kimiloid (trade name, Kimitsu Chemical), Duck Lloyd (trade name, Kibun Food Chemifa), etc. is there.

2) Examples of the resin having an epoxy group include glycidyl (meth) acrylate, 4-epoxystyrene, a copolymer of 1,2,1-vinylcyclohexene 4-5-oxide and a hydrophilic monomer, and the like. No. 3) Examples of the resin having a carboxyl group include poly (meth) acrylic acid, copolymers of (meth) acrylic acid, crotonic acid, maleic acid and a hydrophilic monomer, natural products, polymerized rosin, hydrogenated rosin , Disproportionated rosin, polyester resin having an acid value, and the like.

4) Examples of the resin having an amino group include the following. -Copolymer of acrylamide and its derivative and hydrophilic monomer Here, as the acrylamide, for example, N-methylacrylamide, N, N-dimethylacrylamide,
N, N-dimethylaminoethyl acrylate, N, N-dimethylaminopropyl acrylate, hydroxymethyl
(Meth) acrylate, β- (urea) -N-ethylene acrylate, β- (urea) -N-ethylene acrylate,
N, N-dimethylaminoethyl methacrylate, N, N-
Dimethylaminopropyl methacrylate, N, N-dimethylaminoacrylamide, N, N-dimethylamino (meth) acrylamide, N, N-dimethylaminoethyl methacrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N, N- Dimethylamino 2-hydroxypropyl (meth) acrylamide, N-methyl-N-
Ethyl acrylamide, N-methyl-NN-propylacrylamide, N-methyl-N-isopropylacrylamide, N-ethylacrylamide, N, N-diethylacrylamide, Nn-butylacrylamide, N
-Sec-butylacrylamide, N-tert-butylacrylamide, Nn-propyl (meth) acrylamide, N, N-di-n-propylacrylamide, N-
Isopropyl (meth) acrylamide, N-cyclopropyl (meth) acrylamide, N, N-di-isopropylacrylamide, Nn-hexylacrylamide, N-
n-octylacrylamide, N-tert-octylacrylamide, N-tetrahydrofurfuryl (meth) acrylamide, N-hydroxyethylacrylamide,
N-methoxymethylacrylamide, N-methoxyethyl (meth) acrylamide, N-methoxypropyl (meth)
Acrylamide, N-ethoxymethylacrylamide,
N-ethoxyethyl (meth) acrylamide, N-ethoxypropyl (meth) acrylamide, Nn-butoxymethylacrylamide, Nn-butoxypropylacrylamide, N-isopropoxypropyl (meth) acrylamide, N- (2,2 -Dimethoxyethyl) -N-methylacrylamide, N-1-methyl-2-methoxyethyl
(Meth) acrylamide, N-1-methoxymethylpropyl (meth) acrylamide, N- (1,3-dioxolane-
2-ylmethyl) -N-methylacrylamide, N-methylolacrylamide, diacetoneacrylamide,
N-2-ethylhexyloxypropyl acrylamide,
N-furfurylacrylamide, N-methylthiopropylacrylamide, N-chloropropylacrylamide, N-acryloylpiperidine, N-acryloylpyrrolidine, N-acryloylmorpholine, 2-methyl-
5-vinylpyridine, N-vinyl-2-pyrrolidone, N
-Acryloyl-2,6-dimethylmorpholine and the like, and quaternary compounds thereof.・ Polyallylamine, ethyleneimine copolymer

Specific examples of the hydrophilic resin, which is the component A, which can be used in the present invention are described in the above 1) to 4). The hydrophilic resin used in the case of forming the copolymer shown therein is used. Examples of such hydrophilic monomers are given below.・ Monomer having sulfonic acid group: Sodium vinyl sulfonic acid, vinyl benzene sulfonic acid salt, etc. ・ Monomer having carboxylic acid: (meth) acrylic acid, itaconic acid, succinic anhydride, maleic anhydride, etc. ・ Monomer having hydroxyl group: Polyoxyethylene (meth) acrylate, β-hydroxyethylene vinyl ether,
β-hydroxyethylene (meth) acrylate, trimethylolpropane monomethacrylate, pentaerythritol monomethacrylate, etc. Monomers having an amide group: (meth) acrylamide, monomethylol (meth) acrylamide, β- (urea) -N
-Ethylene acrylate, β- (urea) -N-ethylene acrylate, methacrylyl dicyandiamide, diacetone acrylamide ・ Monomer having ether group: ethylene oxide, propylene oxide, etc. ・ Monomer having pyrrolidone group: vinylpyrrolidone, etc. ・ having ethyleneimine group Monomer: ethyleneimine,
N-ethyleneiminoethyl methacrylate

In the present invention, monomers having an ethylene oxide chain in the side chain can also be effectively used as a hydrophilic monomer. Specific examples thereof include (a) an acrylate ester having an ethylene glycol chain in a side chain and (b) an acrylate ester having an ethylene glycol chain having an alkyl ether at the side chain terminal. (A) An acrylate ester having an ethylene glycol chain in a side chain and represented by the following general formula CH ₂ ＣC (R) —COO— (CH ₂ CH ₂ O) _n —H (where n is 2 to 24) And R represents a methyl group or a hydrogen atom.)

Specific examples of the above (a) include, for example, the following. _{· CH 2 = C (CH 3} ) -COO- (CH 2 CH 2 O) n -H
(N = 1.9, trade name: BLEMMER PE-90, manufactured by NOF _{Corporation) · CH 2 = C (CH} 3) -COO- (CH 2 CH 2 O) n -H
(N = 4.4, trade name: BLEMMER PE-200, manufactured by NOF _{Corporation) · CH 2 = C (CH} 3) -COO- (CH 2 CH 2 O) n -H
(N = 7.7, trade name: Blemmer PE-350, manufactured by NOF Corporation)

(B) Acrylic ester represented by the following general formula having an ethylene glycol chain of an alkyl ether at the side chain terminal: CH ₂ ＣC (R) —COO— (CH ₂ CH ₂ O) _m — (CH ₂ ) _p −
H (wherein, m represents an integer of 2 to 24, p represents an integer of 1 to 16, and R represents a methyl group or a hydrogen atom.)

Specific examples of the above (b) include, for example, those having an ethylene oxide chain in a side chain as described below. -Methoxy triethylene glycol acrylate (where R = H, m = 3, p = 1, trade name: NK ester AM-30G, manufactured by Shin-Nakamura Chemical Co., Ltd.)-Methoxy polyethylene glycol # 400 acrylate (where R = H, m = about 10, p = 1, trade name:
NK ester AM-90G, manufactured by Shin-Nakamura Chemical Co., Ltd. ・ Methoxydiethylene glycol methacrylate (in the above formula, R = CH ₃ , m = 2, p = 1, trade name: NK ester M-20G, manufactured by Shin-Nakamura Chemical Industry)・ Methoxytetraethylene glycol methacrylate
(Where R = CH ₃ , m = 4, p = 1, trade name: NK
Ester M-40G, manufactured by Shin-Nakamura Chemical Co., Ltd. • Methoxy polyethylene glycol # 400 methacrylate (R = CH ₃ , m = about 10, p = 1, trade name: NK
Ester M-90G, manufactured by Shin-Nakamura Chemical Co., Ltd. ・ Methoxypolyethylene glycol # 1000 methacrylate (R = CH ₃ , m = about 24, p = 1, trade name: N
K ester M-230G, manufactured by Shin-Nakamura Chemical Co., Ltd. ・ Butoxydiethylene glycol acrylate (R =
H, m = 2, p = 4, trade name: NK ester AB-20
G, Shin-Nakamura Chemical Co., Ltd.)

In the present invention, among the hydrophilic monomers used for forming the above-mentioned copolymer,
In particular, it is preferable to use a monomer in which a homopolymer obtained from the monomer has water solubility. In addition, it is preferable that the polymer of the component A has a repeating unit having a hydroxyl group in a range of 20 to 80% by weight in both a substance modified from a homopolymer and a substance obtained by copolymerization. . Further, when the polymer of the component A has no hydroxyl group, it is preferable that the total of the other hydrophilic monomers exemplified above is used in the range of 45 to 70% by weight.

As the hydrophilic resin as the component A used in the present invention, the amount of the ethylenically unsaturated group introduced into the side chain is as follows:
When the unsaturated bond concentration is expressed in terms of the number of moles of ethylenically unsaturated bonds in 1 kg of the resin, m = 0.1 to 2.0 is used. When m is more than 2.0, the crosslinking density becomes too high, and when the ink receiving layer is formed, sufficient ink absorbency cannot be maintained. Conversely, m is 0.1
If the amount is less than the above range, sufficient water fastness cannot be obtained when the ink receiving layer is formed.

[0024] As the hydrophilic resin is an A component used in the present invention, the glass transition temperature of the resin (hereinafter abbreviated as T _g)
However, it is preferable to use one in the range of 40 to 140 ° C, and more preferably, one in the range of 60 to 100 ° C.
That is, when T _g is lower than 40 ° C., even if the B component is mixed to form a crosslinked structure, the film formability is poor and the film becomes sticky. Conversely, if T _g is higher than 140 ° C., the strength of the coating is too high, which causes curling when applied to a substrate such as a film to form an ink receiving layer.

From the viewpoint of film forming properties, the molecular weight of the hydrophilic resin as the component A is 5,000 to 5,000 in terms of weight average molecular weight.
It is preferably in the range of 300,000, more preferably 10,000 to 200,000, and still more preferably 3
Those having a range of 000 to 100,000 are used.

As described above, the preferred hydrophilic resin material used as the component A in the present invention has been described. However, since these physical properties are mutually related, the optimum value is determined by the combination of the selected components. Change. That is, in the present invention, since the balance between the ink absorbency and the water resistance is important, it is necessary to mutually adjust the physical properties according to the degree of hydrophilicity. Therefore, when a resin having high hydrophilicity is used as the resin serving as the skeleton, it is necessary to increase the amount of ethylenically unsaturated bonds introduced into the side chain. In general, the higher the molecular weight is, the lower the solubility is. Therefore, when a resin having a high molecular weight is used as the resin serving as the skeleton, it is necessary to adjust the amount of the ethylenically unsaturated group or the like.

Next, the hydrophilic oligomer as Component B, which is another constituent material of the curable composition of the present invention, will be described. The component B used in the present invention has a function of cross-linking the hydrophilic resin as the component A as described above, and giving the formed ink receiving layer water resistance. Specifically, the component B is a hydrophilic oligomer having a weight average molecular weight of 400 to 3,000 and having 2 to 4 ethylenically unsaturated groups at the molecular terminals. As described above, by using a hydrophilic oligomer having 2 to 4 ethylenically unsaturated groups as functional groups in the molecule, crosslinking can be performed without impairing the ink absorbency of the hydrophilic resin of the component A. I can do it.

Examples of the component B include a hydrophilic oligomer having an alkylene glycol skeleton such as ethylene glycol, propylene glycol and tetramethylene glycol, and a hydrophilic oligomer such as a modified polyhydroxy compound. And those having 2 to 4 ethylenically unsaturated groups introduced. Specifically, it is preferable to use, for example, the following components a. To j. a. Of alkylene oxide adducts of polyhydric alcohols
(Meth) acrylate b. Terminal acrylic acid ester of urethane-modified compound of polyalkylene oxide c. Terminal acrylate of polyester modified compound of polyalkylene oxide d. Acrylic acid ester of epoxy-modified compound of polyalkylene oxide e. Acrylic ester of alkylene oxide adduct of melamine f. Acrylic acid ester of alkylene oxide adduct of isocyanurate g. Acrylic acid ester of alkylene oxide adduct of hydantoin h. Cationized acrylic of polyalkylene oxide compound i. Cationic acrylates of epoxy esters of polyalcoholene oxide.

Specific examples of the above compounds a. To j. Include the following. a. Of alkylene oxide adducts of polyhydric alcohols
(Meth) acrylic acid ester For example, ethylene glycol di (meth) acrylate, propanediol diol di (meth) acrylate, butanediol di (meth) acrylate, pentanediol di
(Meth) acrylate, hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, neopentyl glycol dihydroxypivalate
(Meth) acrylate, polyethylene glycol di (meth)
Examples include acrylate, polypropylene glycol di (meth) acrylate, polytetrafuran glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, and pentaerythritol tetra (meth) acrylate. Further, as these specific products, for example, Kayarad DPCA-120, Kayarad DPCA
-20, Kayarad DPCA-30, Kayarad DPC
A-60, Kayarad R-526, Kayarad R-62
9. Kayarad R-644 (brand name: Nippon Kayaku)
NK Ester A-4200, A-600,
A-800, A-1000, NK ester APG-4
00, APG-700 (Trade name: Shin-Nakamura Chemical Co., Ltd.)
ENT-2000, ENT-3400, EN
TP-4000 (above, manufactured by Kansai Paint Co., Ltd.)
And the like.

B. Terminal acrylic acid ester of urethane-modified compound of polyalkylene oxide Examples thereof include the following (i) to (iv). (i) A urethane compound whose terminal is isocyanate synthesized from bisphenol A and hexamethylene diisocyanate is reacted with 2-hydroxyethyl acrylate to have a number average molecular weight of about 2,600, and both terminals of the molecule. Is acryloyl urethane acrylate (ii) a urethane compound whose terminal is isocyanate synthesized from polytetramethylene glycol and tolylene diisocyanate is reacted with 2-hydroxyethyl acrylate to have a number average molecular weight of about 1, 800, urethane acrylate having acryloyl at both ends of the molecule (iii) reacting 2-hydroxyethyl acrylate with a urethane compound having isocyanate at the end synthesized using propylene oxide, ethylene oxide and xylylene diisocyanate Urethane acrylate having a number average molecular weight of about 1,800, and both ends of the molecule being acryloyl (iv) for a urethane compound having a molecular weight of 400, which is synthesized using polyethylene oxide and lysine diisocyanate and having a terminal of isocyanate , 2-hydroxyethyl methacrylate reacted with a number average molecular weight of about 3,
100, urethane acrylate in which both terminals of the molecule are acryloyl

Examples of these specific products include Aronix M-1100 and Aronix M-12.
00 (trade name, manufactured by Toa Gosei Chemical Industry Co., Ltd.), NK
Oligo U-4HA, U-108A, U-1084A, U
-200AX, U-122A (trade names, manufactured by Shin-Nakamura Chemical Co., Ltd.) and the like.

C. Terminal acrylate of polyester modified compound of polyalkylene oxide For example, (meth) acrylate of polyester can be mentioned. Examples of these specific products include, for example, Aronix M-6100 and Aronix M-62.
00, Aronix M-6250, Aronix M-6
300, Aronix M-6400, Aronix M-
7100, Aronix M-8030, Aronix M
-8100 (trade name, manufactured by Toa Gosei Chemical Industry Co., Ltd.)
And the like.

D. Acrylic acid ester of epoxy-modified compound of polyalkylene oxide For example, polyethylene glycol diglycidyl ether di (meth) acrylate, 1,6-hexanediol diglycidyl ether di (meth) acrylate, trimethylolpropane triglycidyl ether tri (meth) acrylate , Glycerin triglycidyl ether tri (meth) acrylate, glycerin triglycidyl ether tri
(Meth) acrylate, triglycidyl ether isocyanurate tri (meth) acrylate, (meth) acrylate of novolak type epoxy resin, (meth) acrylate of bisphenol type epoxy resin, etc. (Meth) acrylic acid esters of compounds having an epoxy group. These products include, for example, Denacol Acrylate DM201, DM
-811, DM-851, DM-832, DA-91
1, DA-920, DA-931, DA-314, DA
-701, DA-721, DA-722 (trade names, manufactured by Nagase Kasei Kogyo Co., Ltd.), NK Oligo EA-102
0, EA-6320, EA-6310 (trade names)
Shin-Nakamura Chemical Co., Ltd.).

E. Acrylic ester of alkylene oxide-added compound of melamine For example, melamine acrylate obtained by adding ethylene oxide at a ratio of 30 moles to 1 mole of melamine, followed by acryl esterification with acrylic acid chloride, and the like.

F. Acrylic acid ester of alkylene oxide addition compound of isocyanurate For example, an isocyanurate acrylate compound obtained by adding 18 mol of ethylene oxide to 1 mol of isocyanurate and then acrylic-esterifying with acrylic acid chloride is exemplified.

G. Acrylate ester of an alkylene oxide addition compound of hydantoin For example, a hydantoin acrylate compound obtained by adding 24 mol of ethylene oxide to 1 mol of hydantoin and then acryl-esterifying with acrylic acid chloride, or 1 mol of hydantoin,
A hydantoin acrylate compound obtained by adding a mole and then acryl-esterifying with acrylic acid chloride is exemplified.

H. Addition reaction product of polyepoxide of polyalkylene oxide compound with tertiary amine For example, a compound obtained by reacting polyepoxide of polyglycerin with acrylic acid and trimethylamine is exemplified.

I. Cationized acrylate of epoxy ester of polyalkylene oxide For example, a compound obtained by reacting dimethylaminoethyl methacrylate with diglycidyl ether of polyethylene oxide can be used.

The hydrophilic oligomer which is the component B used in the present invention has 2 to 4 reactive ethylenically unsaturated groups at the molecular terminals and has a molecular weight of 400 to 3,000.
Use a value in the range of 0. More preferably, the component B having a molecular weight in the range of 600 to 2,000 is used. When the molecular weight of the hydrophilic oligomer of the component B is smaller than 400, the distance between the crosslinking points becomes small, and it becomes difficult to maintain the ink absorbency. On the other hand, if it is larger than 3,000, even if a crosslinked structure is formed, the water resistance of the ink receiving layer is insufficient, and the intended object of the present invention cannot be achieved. Similarly to the component A, also in the case of the hydrophilic oligomer of the component B, the optimum amount and molecular weight of the ethylenically unsaturated group are determined by the mutual relationship of the compounds used. That is, A
When the concentration of the ethylenically unsaturated group of the component or the component B is high, it is preferable to adjust the crosslinking density by using a component B having a higher molecular weight. In addition, when a substance having high water solubility is used for the resin or oligomer used as the component A and the component B, it is desirable to use a substance having a small molecular weight or a substance having a large amount of ethylenically unsaturated groups as the component B.

The mixing ratio of the component A and the component B in the curable composition of the present invention is such that the amount of ethylenically unsaturated bond of each of the component A and the component B is 1/1 to 10/1. Mixing is preferred. The mixing ratio also depends on the material of the hydrophilic resin of the component A, the amount of the ethylenically unsaturated bond, the molecular weight of the resin, the type of the oligomer of the component B, the molecular weight, and the like. Therefore, the mixing ratio may be determined in consideration of the balance between the ink absorbency and the water resistance.

Further, the curable composition of the present invention preferably contains a compound which can be activated by heat or active energy rays, in addition to the above-mentioned components A and B. As described above, in the present invention, the hydrophilic resin which is the component A constituting the skeleton of the ink receiving layer is crosslinked by mixing the hydrophilic oligomer which is the component B, and the water resistance of the ink receiving layer is increased. It is possible to have. That is, the curable composition of the present invention comprising a mixture of the component A and the component B composed of the above-described materials is applied to a substrate, and then cured by heat or active energy rays to form an ink receiving layer. Then, it is possible to easily form the ink receiving layer having high adhesion to the substrate in a short time. Further, since the formed ink receiving layer has a cross-linked structure, when printing is performed by the inkjet recording method, the ink absorption is good, the optical density of dots is high, and the periphery of the dots is clear and high without being blurred. An excellent performance can be obtained in which an image having a resolution can be formed and water fastness is further improved. Therefore, the curable composition of the present invention preferably contains a catalyst for promptly promoting curing.

The following catalysts can be added to the curable composition of the present invention to accelerate curing. In particular, as a catalyst in the active energy ray curing reaction, for example, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- (4-isopropylphenyl) -2-hydroxy -2-methylpropan-1-one, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2-hydroxy-
2-methyl-1-phenylpropan-1-one, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1,4-phenoxydichloroacetophenone, 4- (2-hydroxyethoxy) Acetophenones such as phenyl (2-hydroxy-2-propyl) ketone, pt-butyldichloroacetophenone, pt-butyltrichloroacetophenone and p-dimethylaminoacetophenone; benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether; Benzoin ethers such as benzoin n-butyl ether, benzoin isobutyl ether, and benzyl dimethyl ketal; benzophenone, benzophenone methyl ether, benzoylbenzoic acid, methyl benzoylbenzoate,
Hydroxybenzophenone, 4-phenylbenzophenone, 3,3'-dimethyl-4-methoxybenzophenone, 3,3'-bis (N, N-dimethylamino) benzophenone, 4,4'-bis (N, N-diethylamino)
Benzophenone, 4 ', 4 "-diethylisophthalophenone, 3,3', 4,4'-tetra (t-butyl-oxycarbonyl) benzophenone, 4-benzoyl-4'-methyldiphenylsulfide, acrylated benzophenone, etc. Benzophenones; thioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4
-Xanthones such as dimethylthioxanthone, 2,4-diethyloxanthone, 2,4-diisopropylthioxanthone, 2-chlorothioxanthone and 2,4-dichlorothioxanthone; diketones such as diacetyl and benzyl; 2-ethylanthraquinone; t-butylanthraquinone, 2,3-diphenylanthraquinone, 1,2-benzanthraquinone, octitamethylanthraquinone,
Quinones such as camphorquinone, dibenzosuberone, and 9,10-phenanthrenequinone; and the like. or,
Also useful are CGI 1700, CGI 149 (a blend product based on bisacylphosphine oxide, manufactured by Nippon Ciba Geigy).

Some of these substances have low solubility in the solvent of the resin. In such a case, they have a relatively wide solubility represented by N-methylpyrrolidone.
An aprotic polar solvent may be used in combination. These catalysts are preferably added in a range of 3 to 10% based on the total amount of the component A and the component B.

The components A and B, which are essential components of the curable composition of the present invention, and the catalyst used as required have been described above. The curable composition of the present invention further comprises Other components such as those shown below may be added. For example, it is preferable to mix a dye-dyeable substance into the curable composition of the present invention in order to enhance the effect of waterfastness. The dye-dyeing substance may be already used as a resin or an oligomer constituting the skeleton of the component A or the component B, but when not used, the dye-dyeing substance is used as another component. It is preferable to mix substances having the following properties. As a substance having dyeing properties, for example,
Those having a tertiary amine group, a quaternary ammonium group, and a cationic group are exemplified. These include the following.

For example, cationically modified products of resins such as polyvinyl alcohol and hydroxyethylcellulose), cationic resins of main chain type, cationic polymers such as amine resins such as polyallylamine, polyallylsulfone and polydiallylamine; A cationic surfactant such as a secondary or tertiary amine salt type compound, laurylamine,
Hydrochlorides and acetates such as cocoamine, stearylamine and rosinamine, quaternary ammonium salts such as lauryltrimethylammonium chloride, lauryldimethylbenzylammonium chloride and benzyltributylammonium chloride, and pyridinium salts such as benzalkonium chloride , Cetylpyridinium chloride, cetylpyridinium bromide and the like, imidazoline-type cationic compounds, 2-heptadecenyl-hydroxyethylimidazoline and the like, higher alkylaminenoethylene oxide adducts, dihydroxyethylstearylamine and the like.

Further, in order to obtain quick ink absorption (ink absorption speed and ink absorption amount), fine particles having voids may be dispersed in the curable composition of the present invention. Examples of such a substance include extender pigments such as titanium oxide, silica, alumina, talc, and clay, inorganic salts, and organic fine particles, which are conventionally known as extender pigments. It is necessary to add these components to such an extent that the water resistance of the ink receiving layer is not impaired, and it is preferable to add them in a range of 15% or less based on the total amount of the components A and B.

When a curable composition of the present invention as described above is applied on a substrate to produce a recording medium having an ink receiving layer laminated thereon, the thickness of the ink receiving layer is adjusted by ink jet printing. In the case of the recording medium to be used, the curable composition of the present invention has a cured coating film having a thickness of 3 to 100 μm,
Preferably, the thickness is 5 to 50 μm. When the recording medium is used for printing using an aqueous ink with thermal drying such as gravure printing or flexographic printing, the thickness of the ink receiving layer is 0.5 to 50 μm, preferably 1 to 50 μm.
The thickness is preferably 20 μm.

The curable composition of the present invention is particularly preferably used as a material for forming an ink receiving layer for a water-based inkjet ink. That is, prior to printing using an inkjet printer, a coating liquid comprising the curable composition of the present invention is applied to a non-absorbable substrate, and then cured to form an ink receiving layer. As a method of applying the coating liquid at that time, any of existing coating means such as a spinner, a roll coater, a spray coater, and screen printing can be applied. Further, after performing such coating, the solvent is evaporated and dried, and the ink is polymerized and solidified by heat or electron beam irradiation or ultraviolet irradiation to form an ink receiving layer.

The above-mentioned curing means is appropriately selected and used depending on the materials of the component A and the component B which are the constituent materials of the curable composition of the present invention. For example, as the heating means, the substrate is preferably placed in a hot blast stove at a temperature of about 80 to 200 ° C. As the ultraviolet irradiation means, it is preferable to irradiate ultraviolet rays of about 200 to 1000 mJ / cm ^{2 in} total from a high-pressure mercury lamp. When an electron beam irradiation device is used, it is preferable to perform irradiation in the range of 1 to 50 Mrad. In the case of performing the polymerization treatment by electron beam irradiation at the time of curing, it is a matter of course that those skilled in the art remove the ultraviolet curing catalyst from the coating liquid.

The curable composition of the present invention can be applied to various media (substrates), and forms an ink-receiving layer on the surface of a material as described below. Also enables printing using an inkjet printer. As a support to be used, for example, films such as polyethylene terephthalate, cellulose acetate, polycarbonate, polyvinyl chloride, polystyrene, polysulfone, and aliphatic polyester film, metal plate, plastic, rubber, ceramics, cloth, leather, glass, and cardboard And the like.

Next, an example of an ink jet recording apparatus suitably used for printing on a recording medium having an ink receiving layer formed of the curable composition of the present invention will be described below. FIGS. 1, 2 and 3 show examples of the configuration of a head which is a main part of the apparatus. The head 13 includes a glass, ceramic or plastic plate or the like having a groove 14 through which ink passes, and a heating head 15 (a thin film head is shown in the figure, but is not limited to this) used for thermal recording. Are obtained by bonding. The heating head 15 has a good heat dissipation property such as a protective film 16 formed of silicon oxide or the like, aluminum electrodes 17-1 and 17-2, a heating resistor layer 18 formed of nichrome or the like, a heat storage layer 19, and alumina. It consists of a substrate 20.

The ink 21 has a discharge orifice (fine hole) 2
2, and a meniscus 23 is formed by a pressure (not shown). Now, aluminum electrodes 17-1 and 17
When electric signal information is added to -2, the area indicated by n of the heating head 15 generates heat rapidly, bubbles are generated in the ink 21 in contact with the area, and the meniscus 23 protrudes due to the pressure, and the ink 21 is ejected. The ink orifices 22 fly toward the recording material 25 from the ejection orifices 22.

FIG. 3 is an external view of a multi-head in which a number of heads shown in FIG. 1 are arranged. The multi-head is manufactured by closely contacting a glass plate 27 having a multi-groove 26 and a heating head 28 similar to that described with reference to FIG. FIG. 1 is a cross-sectional view of the head 13 along the ink flow path.
FIG. 2 is a sectional view taken along line AB in FIG.

FIG. 4 shows an example of an ink jet recording apparatus incorporating the above head. In FIG. 4, reference numeral 61 denotes a blade as a wiping member, one end of which is held by a blade holding member to become a fixed end, and forms a cantilever. The blade 61 is arranged at a position adjacent to a recording area of the recording head 65, and in the present example, is held in a form protruding into the movement path of the recording head 65. Reference numeral 62 denotes a cap on the ejection port surface of the recording head 65, which is disposed at a home position adjacent to the blade 61, moves in a direction perpendicular to the moving direction of the recording head 65, and comes into contact with the ink ejection port surface to perform capping. It has a configuration to perform. Further, reference numeral 63 denotes an ink absorber provided adjacent to the blade 61, which is held in a form protruding into the movement path of the recording head 65, similarly to the blade 61.

The blade 61, the cap 62, and the ink absorber 63 constitute an ejection recovery section 64, and the blade 61 and the ink absorber 63 remove moisture, dust, and the like from the ink ejection port surface. A recording head 65 having ejection energy generating means for ejecting ink to a recording material facing an ejection port surface provided with ejection ports to perform recording;
Reference numeral 6 denotes a carriage on which the recording head 65 is mounted and moved. The carriage 66 is slidably engaged with the guide shaft 67, and a part of the carriage 66 is connected to a belt 69 driven by a motor 68 (not shown).
As a result, the carriage 66 can move along the guide shaft 67, and the recording head 65 can move the recording area and the adjacent area.

Reference numeral 51 denotes a sheet feeding unit for inserting a recording material, and 5
Reference numeral 2 denotes a paper feed roller driven by a motor (not shown). With such a configuration, the recording material is fed to a position facing the discharge port surface of the recording head 65, and is discharged to a discharge section provided with a discharge roller 53 as recording proceeds.

In the above configuration, when the recording head 65 returns to the home position at the end of recording or the like, the cap 62 of the ejection recovery section 64 is retracted from the moving path of the recording head 65, but the blade 61 protrudes into the moving path. I have. As a result, the ejection port surface of the recording head 65 is wiped.
When capping is performed by contacting the cap 62 with the ejection port surface of the recording head 65, the cap 62 moves so as to protrude into the moving 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 at the same position as the position at the time of wiping described above. As a result, the ejection port surface of the recording head 65 is also wiped during this movement. The movement of the print head 65 to the home position is performed not only at the end of printing or at the time of ejection recovery, but also at the home position adjacent to the printing area at a predetermined interval while the printing head 65 moves through the printing area for printing. And the wiping is performed with this movement.

FIG. 5 is a diagram showing an example of an ink cartridge containing ink supplied to the head via an ink supply member, for example, a tube. Here, reference numeral 40 denotes an ink storage unit that stores the supply ink, for example, an ink bag, and a rubber stopper 42 is provided at the end thereof. By inserting a needle (not shown) into this stopper 42,
The ink in the ink bag 40 can be supplied to the head. An ink absorber 44 receives the waste ink. It is preferable for the present invention that the ink absorbing portion has a liquid contact surface with the ink formed of polyolefin, particularly polyethylene.

The ink-jet recording apparatus used in the present invention is not limited to the one in which the head and the ink cartridge are separated as described above, but is also suitable for the one in which they are integrated as shown in FIG. Used. In FIG. 6, reference numeral 70 denotes a recording unit, in which an ink storage unit storing ink, for example, an ink absorber is stored, and a head unit having a plurality of orifices in which the ink in the ink absorber is stored. It is configured to be ejected from 71 as ink droplets.

As the material of the ink absorber, it is preferable for the present invention to use polyurethane, cellulose or polyvinyl acetal. Reference numeral 72 denotes an atmosphere communication port for communicating the inside of the recording unit with the atmosphere. The recording unit 70 is used in place of the recording head shown in FIG. 4, and is detachable from the carriage 66.

[0062]

Next, the present invention will be described more specifically with reference to examples and comparative examples. In the following description, “parts” and “%” are based on weight unless otherwise specified. First, examples of the synthesis of the hydrophilic resin used as the component A in the examples are shown below.

(A-1) A resin was obtained by reacting 100 parts by weight of polyvinyl alcohol (trade name: PVA217, manufactured by Kuraray) with 20 parts by weight of succinic anhydride to effect esterification. 70 parts by weight of the obtained resin was reacted with 20 parts by weight of glycidyl methacrylate to introduce an ethylenically unsaturated group into the hydrophilic resin to obtain compound A-1. The unsaturated bond concentration m of the ethylenically unsaturated group of the obtained resin (1 kg of resin)
The number of moles of ethylenically unsaturated bonds in the formula) was m = 2. The glass transition temperature T _g was 94 ° C., and the weight average molecular weight was 80,000.

(A-2) 100 parts by weight of polyvinyl alcohol (trade name: PVA217, manufactured by Kuraray) was reacted with 10 parts by weight of succinic anhydride to obtain a resin by esterification. 70 parts by weight of the obtained resin was reacted with 10 parts by weight of glycidyl methacrylate to introduce an ethylenically unsaturated group into the hydrophilic resin to obtain compound A-2. The unsaturated bond concentration of the ethylenically unsaturated group in the obtained resin was m = 1. The glass transition temperature T _g was 90 ° C., and the weight average molecular weight was 80,000.

(A-3) A resin esterified by reacting 5 parts by weight of succinic anhydride with 100 parts by weight of polyvinyl alcohol (trade name: PVA217, manufactured by Kuraray Co., Ltd.) was obtained. 70 parts by weight of the obtained resin was reacted with 5 parts by weight of glycidyl methacrylate to introduce an ethylenically unsaturated group into the hydrophilic resin to obtain a compound A-3. The unsaturated bond concentration of the ethylenically unsaturated group in the obtained resin was m = 0.5. The glass transition temperature T _g was 87 ° C. and the weight average molecular weight was 80,000.

(A-4) Glycidyl methacrylate / vinyl pyrrolidone / hydroxyethyl methacrylate (=
12/66/22) 100 parts by weight of the acrylic resin copolymerized with 3.5 parts by weight of acrylic acid and 0.6 parts by weight of succinic acid were added to esterify, and an ethylenically unsaturated group was introduced into the hydrophilic resin. As a result, compound A-4 was obtained. The unsaturated bond concentration of the ethylenically unsaturated group in the obtained resin was m = 0.5. The glass transition temperature T _g was 91 ° C., and the weight average molecular weight was 50,000.

(A-5) Acrylic acid / acrylate (trade name: Blemmer PE-200, manufactured by NOF Corporation) /
Compound A was prepared by reacting 2.5 parts by weight of glycidyl methacrylate with 60 parts by weight of an acrylic resin copolymerized with methyl methacrylate (= 7/65/28) to introduce an ethylenically unsaturated group into a hydrophilic resin. -5 was obtained.
The unsaturated bond concentration of the ethylenically unsaturated group in the obtained resin was m = 0.8. The glass transition temperature T _g is 6
At 0 ° C., the weight average molecular weight was 70,000.

(A-6) 1 part by weight of glycidyl methacrylate is reacted with 70 parts by weight of an acrylic resin copolymerized with acrylamide / acrylonitrile / methyl methacrylate (= 48/11/41) to esterify the resin, and the hydrophilic resin is converted into ethylene. The compound A-6 was obtained by introducing the unsaturated group. The unsaturated bond concentration of the ethylenically unsaturated group in the obtained resin was m = 0.3. The glass transition temperature T _g was 105 ° C., and the weight average molecular weight was 30,000.

(A-7) A compound obtained by condensing 10 parts by weight of N-methylolacrylamide with 100 parts by weight of polyvinyl alcohol (trade name: PVA217, manufactured by Kuraray) to introduce an ethylenically unsaturated group into a hydrophilic resin. A-7 was obtained. The unsaturated bond concentration of the ethylenically unsaturated group in the obtained resin was m = 0.1. Also, the glass transition temperature T _g
Was 90 ° C. and the weight average molecular weight was 80,000.

(A-8) Methyl methacrylate / N, N
-Dimethylaminopropyl acrylate / acrylamide / glycidyl methacrylate (= 2/24/36/1
To 100 parts by weight of the acrylic resin copolymerized in 4), 4.4 parts by weight of acrylic acid and 0.2 parts by weight of succinic acid were added to esterify, and an ethylenically unsaturated group was introduced into the hydrophilic resin to obtain a compound A- 8 was obtained. The unsaturated bond concentration of the ethylenically unsaturated group in the obtained resin was m = 1. The glass transition temperature T _g was 97 ° C. and the weight average molecular weight was 100,000.

Table 1 below summarizes the ethylenically unsaturated bond amount, molecular weight, and glass transition temperature of the hydrophilic resin used as the component A synthesized as described above.

[0072]

[Table 1]

Example 1 Using the component A-1 obtained above, a curable composition of the present invention having the following composition was obtained. A component: 500 parts of an aqueous solution of resin A-1 having a solid content of 20% 500 parts B component: 100 parts of Gly48EA (prototype, epoxy acrylate of 48 mol ethylene oxide adduct of glycerin) Catalyst: Irgacure 2959 (trade name: CIBA) -GEIGY) 6 parts The obtained curable composition was applied to a 100 μm-thick polyethylene terephthalate film (hereinafter simply referred to as a PET film) using a bar coater, and then heated at 85 ° C for 10 hours.
After drying for a minute, a layer having a dry thickness of 25 μm was obtained. The PET film coated with this layer was irradiated with ultraviolet rays of 400 mJ / cm ^{2 in} total from a high-pressure mercury lamp and reacted to form an ink receiving layer having a crosslinked structure on the PET film.

Example 2 Using the component A-2 obtained above, a curable composition of the present invention having the following composition was obtained. A component: 500 parts of an aqueous solution of 20% solid content of resin A-2 500 parts B component: 70 parts of DENACOL ACRYLATE DM-832 (trade name Nagase Kasei Kogyo) Catalyst: Irgacure 2959 (trade name CIBA-GEIGY) 5 Using the obtained curable composition, coating, drying, and ultraviolet irradiation were performed in the same manner as in Example 1 to obtain a PET film on which an ink receiving layer was formed.

Example 3 Using the component A-3 obtained above, a curable composition of the present invention having the following composition was obtained. A component: 500 parts of an aqueous solution of 20% solid content of resin A-3 500 parts B component: 45 parts of DENACOL ACRYLATE DA-931 (trade name, manufactured by Nagase Kasei Kogyo) Catalyst: Irgacure 2959 (trade name, manufactured by CIBA-GEIGY) 4 Using the obtained curable composition, coating, drying, and ultraviolet irradiation were performed in the same manner as in Example 1 to obtain a PET film on which an ink receiving layer was formed.

Example 4 Using the A-4 component obtained above, a curable composition of the present invention having the following composition was obtained. A component: 500 parts of a 20% solid content of methyl ethyl ketone (hereinafter abbreviated as MEK) solution of resin A-4 500 parts B component: NK Oligo U-108A (trade name, manufactured by Shin-Nakamura Chemical Co., Ltd.) 13 parts Catalyst: Darocur 1173 (Product name: CIBA-GEIGY) 3 parts The obtained curable composition was applied, dried and irradiated with ultraviolet rays in the same manner as in Example 1 to obtain a PET film on which an ink receiving layer was formed. Was.

Example 5 Using the component A-5 obtained above, a curable composition of the present invention having the following composition was obtained. A component: 500 parts of a MEK solution having a solid content of 20% of resin A-5 500 parts B component: GE-NA30 (prototype, a compound obtained by reacting diethanolamine and acrylic acid with a 30 mol addition product of EO of glycerin) 26 Part Catalyst: Darocur 1173 (trade name, manufactured by CIBA-GEIGY) 4 parts Using the obtained curable composition, in the same manner as in Example 1, apply, dry, and irradiate ultraviolet light to form an ink receiving layer. The formed PET film was obtained.

Example 6 Using the component A-6 obtained above, a curable composition of the present invention having the following composition was obtained. -A component: 500 parts of MEK solution with 20% solid content of resin A-6-B component: NK ester A-1000 (trade name, manufactured by Shin-Nakamura Chemical Industry) 10 parts-Catalyst: Irgacure 184 (trade name, manufactured by CIBA-GEIGY) 3 parts) The obtained curable composition was applied, dried, and irradiated with ultraviolet rays in the same manner as in Example 1 to obtain a PET film having an ink receiving layer formed thereon.

Example 7 Using the component A-7 obtained above, a curable composition of the present invention having the following composition was obtained. A component: 500 parts of an aqueous solution of 20% solid content of resin A-7 B component: NK ester APG-700 (trade name, manufactured by Shin-Nakamura Chemical Industry) 80 parts Catalyst: Irgacure 2959 (trade name, manufactured by CIBA-GEIGY) 5 parts The obtained curable composition was applied, dried, and irradiated with ultraviolet rays in the same manner as in Example 1 to obtain a PET film on which an ink receiving layer was formed.

Example 8 Using the component A-8 obtained above, a curable composition of the present invention having the following composition was obtained. -A component: 500 parts of MEK solution with 20% solid content of resin A-8-B component: NK Oligo EA6310 (trade name, manufactured by Shin-Nakamura Chemical Industry) 175 parts-Catalyst: Irgacure 184 (trade name, manufactured by CIBA-GEIGY) 8 Using the obtained curable composition, coating, drying, and ultraviolet irradiation were performed in the same manner as in Example 1 to obtain a PET film on which an ink receiving layer was formed.

Example 9 Using the component A-7 obtained above, a curable composition of the present invention having the following composition was obtained. A component: 500 parts of a MEK solution having a solid content of 20% of resin A-7 500 parts B component: (prototype, a compound obtained by adding 36 mol of EO to hydantoin to give an acrylic acid ester) 78 parts Catalyst: Irgacure 184 (Product name: CIBA-GEIGY) 5 parts The obtained curable composition was applied, dried, and irradiated with ultraviolet rays in the same manner as in Example 1 to obtain a PET film having an ink receiving layer formed thereon. Was.

Comparative Example 1 Using the A-2 component obtained above, a curable composition of Comparative Example not containing the B component having the following composition was obtained. A component: 500 parts of a 20% solids aqueous solution of resin A-2 Catalyst: Irgacure 2959 (trade name: CIBA-GEIGY) 3 parts Using the obtained curable composition, in the same manner as in Example 1. The PET film on which the ink receiving layer was formed was obtained by performing coating, drying, and ultraviolet irradiation.

Comparative Example 2 Using the component A-2 obtained above, a curable composition of the comparative example consisting of the following composition in which the weight average molecular weight of the hydrophilic oligomer of the component B was 200 was obtained. A component: 500 parts of an aqueous solution of 20% solid content of resin A-2 B component: NK ester A-200 (trade name, manufactured by Shin-Nakamura Chemical Co., Ltd.) 30 parts Catalyst: Irgacure 2959 (trade name, manufactured by CIBA-GEIGY) 4 parts The obtained curable composition was applied, dried and irradiated with ultraviolet rays in the same manner as in Example 1 to obtain a PET film on which an ink receiving layer was formed.

Comparative Example 3 A comparative example comprising the following composition using the A-2 component obtained above and the B component being an epoxy acrylate (more than 3,000 in weight molecular weight) of a 72 mol adduct of glycerin with ethylene oxide. Was obtained. -A component: 500 parts of an aqueous solution of 20% solid content of resin A-2-B component: 360 parts of Gly72EA (prototype, epoxy acrylate of ethylene oxide 72 mol adduct of glycerin)-Catalyst: Irgacure 2959 (trade name: CIBA) -GEIGY (14 parts) The obtained curable composition was applied, dried and irradiated with ultraviolet rays in the same manner as in Example 1 to obtain a PET film having an ink receiving layer formed thereon.

Comparative Example 4 A curable composition of Comparative Example having the following composition was obtained without using the component A. -B component: 100 parts of Gly48EA (prototype, epoxy acrylate of 48 mol adduct of ethylene oxide with glycerin)-Catalyst: 3 parts of Irgacure 2959 (trade name: CIBA-GEIGY) The obtained curable composition was used. Coating, drying and UV irradiation were performed in the same manner as in Example 1 to obtain a PET film on which an ink receiving layer was formed.

Comparative Example 5 As the component A, A ′ having an insufficient amount of ethylenically unsaturated groups was used.
Using the -1 component, a curable composition of Comparative Example having the following composition was obtained. A component: 500 parts of an aqueous solution of the following resin A'-1 having a solid content of 20%: 500 parts B component: Gly48EA (prototype, epoxy acrylate of ethylene oxide 48 mol adduct of glycerin) 13 parts Catalyst : Irgacure 2959 (trade name: CIBA-GEIGY) 3 parts (resin A'-1) polyvinyl alcohol (trade name: PV
A217, made by Kuraray) 100 parts by weight of succinic anhydride 1
The resin A′-1 was obtained by reacting 1 part by weight of glycidyl methacrylate with 140 parts by weight of the resin esterified by reacting parts by weight. The unsaturated bond concentration m of the ethylenically unsaturated group (the number of moles of the ethylenically unsaturated bond in 1 kg of the resin) of the obtained resin was m = 0.05. Further, the glass transition temperature T _g was 85 ° C., and the weight average molecular weight was 80,000.

Comparative Example 6 As the component A, an excess of A′-
Using two components, a curable composition of a comparative example having the following composition was obtained. A component: 500 parts of an aqueous solution having a solid content of 20% of the resin A'-2 shown below: 500 parts B component: B component Gly48EA (prototype, epoxy acrylate of a 48 mol adduct of ethylene oxide of glycerin): 1200 parts Catalyst: Irgacure 2959 (trade name CIBA-GEIGY) 40 parts (Resin A'-2) polyvinyl alcohol (trade name: PV
A217, made by Kuraray) 100 parts by weight of succinic anhydride 1
100 parts by weight of the resin esterified by reacting with 00 parts by weight was reacted with 70 parts by weight of glycidyl methacrylate to obtain A′-2. The concentration m of unsaturated bonds of ethylenically unsaturated groups (the number of moles of ethylenically unsaturated bonds in 1 kg of the resin) of the obtained resin was m = 5.0. The glass transition temperature T _g was 97 ° C. and the weight average molecular weight was 80,000. Using the obtained curable composition, coating, drying, and ultraviolet irradiation were performed in the same manner as in Example 1 to obtain a PET film on which an ink receiving layer was formed.

<Printing Test> Examples 1 to 9 and Comparative Examples 1 to
The bubble jet color printer BJC was prepared by using each of the PET films on each of which the ink receiving layer obtained in step 6 was formed.
At -600J (equipped with four water-based dye inks of Canon, yellow, magenta, cyan, and black), test patches of seven colors of yellow, cyan, magenta, black, green, red, and blue were printed. After printing, the ink absorption and water resistance were examined by the following methods and evaluated according to the following criteria.

<Evaluation> Ink Absorbability In the portion where the patch was printed by the above-described method, it was visually observed whether or not there was ink overflow (beading). Those with overflowing inks were marked as x, and those without them were marked with ○. Table 2 shows the evaluation results.

Water resistance: One day after printing, the patch portion was dropped with water using a dropper, and after 30 seconds, a load of 40 g / m ² was applied and the portion was wiped off, and the state was visually observed. In the image of the portion where the water was dropped, there was no disturbance in the image, ○ indicates that the density was lowered, and X indicates that the image was white. Table 2 shows the evaluation results.

[0091]

[Table 2] Evaluation results

As can be seen from Table 2, when the ink receiving layer using the curable composition of the present invention was formed on the PET film, the conventional water-soluble resin used in the comparative example was used. Alternatively, as compared with an ink receiving layer formed of an ultraviolet curable resin, both of the ink absorbing property and the water dyeing resistance are achieved well.

[0093]

As described above, according to the present invention,
An excellent curable composition which is excellent in ink absorbability (ink absorption rate and ink absorption amount) and can easily form an ink receiving layer having high water fastness is provided.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a head of an ink jet recording apparatus.

FIG. 2 is a cross-sectional view of a head of the inkjet recording apparatus.

FIG. 3 is an external perspective view of a head obtained by multiplying the head shown in FIG. 1;

FIG. 4 is a perspective view illustrating an example of an ink jet recording apparatus.

FIG. 5 is a vertical sectional view of the ink cartridge.

FIG. 6 is a perspective view illustrating an example of a recording unit.

[Explanation of symbols]

 13: Head 14: Ink groove 15: Heating head 16: Protective film 17-1, 17-2: Aluminum electrode 18: Heating resistor layer 19: Heat storage layer 20: Substrate 21: Ink 22: Discharge orifice (fine hole) 23 : Meniscus 24: Ink droplet 25: Recording material 26: Multi-groove 27: Glass plate 28: Heating head 40: Ink bag 42: Plug 44: Ink absorber 45: Ink cartridge 51: Paper feed unit 52: Paper feed roller 53: paper discharge roller 61: blade 62: cap 63: ink absorber 64: ejection recovery unit 65: recording head 66: carriage 67: guide shaft 68: motor 69: belt 70: recording unit 71: head unit 72: atmosphere communication mouth

Continuation of the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical indication location C08J 7/04 CEY C08L 33/26 C08L 33/26 C09D 5/00 C C09D 5/00 B41J 3/04 101Y ( 72) Inventor Masahiko Hima 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc.

Claims (11)

[Claims] 1. A curable composition comprising the following components A and B: <Component A> When the unsaturated bond concentration is represented by the number m of ethylenically unsaturated bonds in 1 kg of the resin, the ethylenically unsaturated group is used as a side chain and m is in the range of 0.1 to 2.0. <Component B> Hydrophilic oligomer having a weight average molecular weight of 400 to 3,000 having 2 to 4 ethylenically unsaturated groups at molecular terminals 2. The curable composition according to claim 1, wherein the component B is a hydrophilic oligomer further having an alkylene glycol skeleton. 3. The curable composition according to claim 1, wherein the component B is a hydrophilic oligomer further containing at least one of a tertiary amino group, a quaternary ammonium group, and a cationic group. 4. The curable composition according to claim 1, wherein the component A is a polymer having 20 to 80% by weight of a repeating unit having a hydroxyl group. 5. The composition according to claim 1, wherein the component A is a hydrophilic monomer.
2. The curable composition according to claim 1, wherein the amount of the hydrophilic monomer is acrylamide or a derivative thereof. 6. The glass transition temperature of the component A is from 40 to 14.
The curable composition according to claim 1, which is at 0 ° C. 7. The weight average molecular weight of the component A is 5,000.
The curable composition according to claim 1, wherein the amount is from 300 to 30,000. 8. The component A and the component B in the curable composition have a ratio of the ethylenically unsaturated group of the component A to the ethylenically unsaturated group of the component B of 10/1 to 1/1. The curable composition according to claim 1, wherein the curable composition is mixed. 9. The curable composition according to claim 1, further comprising a compound that can be activated by heat or an active energy ray. 10. A recording medium in which an ink receiving layer is laminated on a substrate, wherein the ink receiving layer is formed of the curable composition according to any one of claims 1 to 9. A recording medium comprising a cured coating having a thickness of 0.5 to 100 μm. 11. After applying the curable composition according to any one of claims 1 to 9 on a substrate, a solvent is evaporated and dried to form a coating film. Alternatively, a method for producing a recording medium, comprising forming an ink receiving layer by irradiating an electron beam to cure the recording medium.