JP2001058461A - Additive and recording medium for ink jet recording - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a recording medium for ink jet recording, with which an image having a high printing density and chroma is obtained, which is excellent in coping with the realization of a multicolor and high speed printing and in the adaptability to a recording device, has general performances as a material to be recorded and can be used in other recording systems. SOLUTION: This additive has a polymerization product obtained through the polymerization of 50 to 100 mol% of an alicyclic (meth)acrylic ester and 0 to 50 mol% of a monomer coplymerizable with the above alicyclic (meth) acrylic ester except the above alicyclic (meth)acrylic ester as its effective component and is cationic. This recording medium is prepared by internally adding or coating the above additive for ink jet recording to or onto a support or only by coating the above additive for ink jet recording with no pigment mixed onto the support.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an additive internally added or applied to a recording medium used in an ink jet recording system, and a recording medium using the same. More specifically, the present invention relates to a novel additive which provides a recording material that forms a recorded image having high resolution and excellent color development.

[0002]

2. Description of the Related Art Conventionally, an ink jet recording system does not require a developing and fixing process, a simple recording apparatus, and easy colorization.
It is widely used because it has lower noise than the dot impact type recording method. As a recording medium for inkjet recording, as disclosed in JP-B-4-15744, in order to increase ink absorbency and image density,
A method of including a cationic resin as a water-proofing agent is known. In addition, in the ink jet recording method, a cationic ink jet suitability improving additive having a cationic property is applied to the paper in order to improve the ink absorbency of the paper and increase the image density in order to record characters, figures, images, and the like satisfactorily. (Japanese Patent Application Laid-Open No. Hei 8-216504) has also been proposed.

[0003]

In recent years, with the remarkable development of printing technology represented by multicolor, high-speed, and precision recording, coated papers are required to have higher printability. It became so. Therefore, the recording medium for ink jet recording (1) increases the recording density and sharpens the color tone.
(2) Improve the ink drying speed and increase the ink absorption capacity. (3) The dots are circular, have no spread, and have sharp edges. (4) The dye has good fixability (water resistance). It is necessary to satisfy these properties.

[0004] However, the conventional technology does not provide a sufficiently satisfactory print density or high-saturation image, and cannot sufficiently cope with multicolor printing and high-speed printing.

The present invention satisfies all of the above requirements and has excellent compatibility with a recording apparatus (does not generate paper dust or curl), and has general performance (strength) as a recording material. It is an object of the present invention to provide a recording medium for ink jet recording that also satisfies the required performances such as having an appropriate printability, and being able to be used in other recording methods (electrophotographic recording, dot recording, etc.).

[0006]

Means for Solving the Problems The present inventors have developed an alicyclic (meta) compound in a recording medium for ink-jet recording for forming a recorded image using an aqueous ink containing a water-soluble dye.
A polymer containing an acrylic ester (the (meth) acrylic ester means an acrylic ester and / or a methacrylic ester, and hereinafter the (meta) has the same meaning) as an active ingredient; and It has been found that a cationic inkjet recording additive is suitable for being internally added to or coated on a support for producing the recording medium.

That is, in the present invention, the proportion of the alicyclic (meth) acrylate is 50 to 100 mol%, and the proportion of the copolymerizable monomer other than the alicyclic (meth) acrylate is 0 to 50 mol%. The polymer obtained by the polymerization as an active ingredient, an ink-jet recording additive having cationic properties, an ink-jet recording medium obtained by internally adding or coating the ink-jet recording additive to a support, and a pigment without mixing. The present invention relates to a recording medium for ink jet recording obtained by coating a support with only an additive for ink jet recording.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The alicyclic (meta) used in the present invention
Examples of the acrylate monomer include cyclohexyl (meth) acrylate, 1-methylcyclohexyl (meth) acrylate, 2-methylcyclohexyl (meth) acrylate, 3-methylcyclohexyl (meth) acrylate, and (meth) acrylic acid 4 -Methylcyclohexyl,
Examples thereof include 3,3,5-trimethylcyclohexyl (meth) acrylate, and isobornyl (meth) acrylate. Among these, cyclohexyl (meth) acrylate is preferable in terms of handleability and ease of monomer preparation. Is preferred.

The polymer used in the present invention is an alicyclic (meth)
A polymer or copolymer of an acrylate ester,
In the case of a copolymer, it is necessary to contain the alicyclic (meth) acrylic acid ester in an amount of 50 mol% or more, preferably 80 mol% or more, more preferably 90 mol% or more. This is because when the proportion of the alicyclic (meth) acrylate in the emulsion polymer is less than 50 mol%, the density of the recorded image is deteriorated.

Examples of the nonionic vinyl monomer copolymerizable other than the above-mentioned alicyclic (meth) acrylate include ethylene, butadiene, styrene, α-methylstyrene, vinyl acetate, alkyl (meth) acrylate, (meth) ) Acrylamide, N-methylol (meth)
Acrylamide, N, N-dimethyl (meth) acrylamide, methylenebisacrylamide, (meth) acrylonitrile, vinylpyridine, vinylpyrrolidone, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and the like. Can be copolymerized within a range that does not impair the stability of the dispersion.

The additive for ink jet recording of the present invention is characterized by containing an alicyclic (meth) acrylic acid ester as an active ingredient, and having cationic properties in order to improve fixability.

Means for imparting cationicity to the ink jet recording additive of the present invention include A) a method of copolymerizing a cationic monomer with an alicyclic (meth) acrylate monomer, and B) an alicyclic (meth) A) a method of adding a cationic substance to a polymer obtained by polymerizing an acrylate monomer and / or a copolymer obtained by copolymerizing an alicyclic (meth) acrylate monomer,
C) a method of polymerizing or copolymerizing an alicyclic (meth) acrylate in the presence of a cationic substance; and D) a method of appropriately combining these three methods.

A) The cationic monomer is alicyclic (meth)
The method of copolymerizing with the acrylate monomer includes the method of formula (I):

[0014]

Embedded image (However, R ₁ is hydrogen or a methyl group, R ₂ is C1 to C4
Or CH ₂ CH (OH) CH ₂ . R ₃ and R ₄ are hydrogen or a C1 to C4 aliphatic alkyl group, glycidyl group, or benzyl group;
Or a monomer having a tertiary amino group represented by the formula (II):

[0015]

Embedded image (However, R ₁ is hydrogen or a methyl group, R ₂ is C1 to C4
Or CH ₂ CH (OH) CH ₂ . R ₃ , R ₄ and R ₅ represent hydrogen or a C1 to C4 aliphatic alkyl group, glycidyl group or benzyl group. Y represents O or NH. X ^- is shown an anion, a halogen ion, sulfate ion, alkyl sulfate ion, alkyl or aryl sulfonic acid ion, an acetate ion. ), Or copolymerizing an alicyclic (meth) acrylate monomer with a tertiary amino group-containing monomer represented by the formula (I). A method of performing quaternary ammonium conversion after polymerization and the like can be given.

Examples of the monomer having a tertiary amino group represented by the formula (I) include N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylamino Propyl (meth) acrylate, N, N-dimethylamino-2
-Hydroxypropyl (meth) acrylate, N, N-
Dimethylaminopropyl (meth) acrylamide and the like.

Examples of the monomer having a quaternary ammonium salt represented by the formula (II) include (meth) acryloyloxyethyltrimethylammonium chloride, (meth)
Acroyloxyethyl dimethylbenzyl ammonium chloride, (meth) acroyloxyethyl triethyl ammonium chloride, (meth) acroyloxyethyl diethyl benzyl ammonium chloride, (meth) acroyloxypropyl trimethyl ammonium chloride, (meth) acroyloxypropyl Triethylammonium chloride, 2-hydroxy-3-
(Meth) acryloyloxypropyltrimethylammonium chloride, (meth) acrylamidopropyltrimethylammonium chloride, (meth) acrylamidopropyldimethylbenzylammonium chloride,
(Meth) acrylamidopropyltriethylammonium chloride, (meth) acrylamidopropyldiethylbenzylammonium chloride, 2-hydroxy-
3- (meth) acrylamidopropyltrimethylammonium chloride and the like.

As a method of copolymerizing with a monomer having a tertiary amino group represented by the formula (I) and then converting it to a quaternary ammonium, an alicyclic (meth) acrylate monomer and a compound of the formula (I) ), And then adding methyl chloride, epichlorohydrin, benzyl chloride, and dimethyl sulfate as quaternizing agents. The amount of the quaternizing agent is appropriately determined according to the amount of the tertiary amino group to be quaternized.

The above cationic monomer is alicyclic (meth)
By copolymerizing with acrylate monomer,
The cationic inkjet recording additive of the present invention is obtained, and the amount of the cationic monomer used in this case is preferably 0.1 mol% or more and 20 mol% or less. This is to improve the fixability of the ink for ink jet recording by increasing the amount of the cationic monomer to 0.1 mol% or more, and to improve the water resistance of the ink jet recording medium. This is for improving the print density of the ink jet recording medium.

B) The method for adding the cationic substance is not particularly limited, but specifically, an alicyclic (meth)
During polymerization of acrylate monomer or alicyclic (meth) acrylate monomer and alicyclic (meth)
A method of adding during the copolymerization with a nonionic vinyl monomer copolymerizable with a compound other than the acrylate monomer, after completion of the polymerization of the alicyclic (meth) acrylate monomer or after the completion of the alicyclic (meth) acrylate monomer Mixed with a nonionic vinyl monomer copolymerizable with a monomer other than the alicyclic (meth) acrylate monomer after completion of the copolymerization, a polymer of the alicyclic (meth) acrylate monomer or an alicyclic ( A method in which a copolymer of a (meth) acrylic acid ester and a nonionic vinyl monomer copolymerizable with a monomer other than the alicyclic (meth) acrylic acid ester monomer is mixed when the copolymer is added to a recording medium.

Examples of the cationic substance include i) a cationic surfactant, ii) a polymer of the above cationic monomer or a copolymer of several kinds of the above cationic monomers, and iii) 50 or more of the above cationic monomers. 1
A copolymer obtained by polymerizing a nonionic vinyl monomer other than the alicyclic (meth) acrylic acid ester, which contains less than 00 mol%, and iv) a method of combining these three methods, and the like. Can be

Examples of the cationic surfactant used in the present invention include dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, octadecyltrimethylammonium chloride, tetradecyldimethylbenzylammonium chloride, octadecyldimethylbenzylammonium chloride and the like.

C) The method of polymerizing or copolymerizing an alicyclic (meth) acrylate in the presence of a cationic substance includes: a) alicyclic (meth) acrylic acid in the presence of a cationic surfactant A method of polymerizing or copolymerizing an ester; b) polymerizing or copolymerizing an alicyclic (meth) acrylate in the presence of a polymer of the above cationic monomer or a copolymer of a combination of several kinds of the above cationic monomers C) a method of polymerizing or copolymerizing an alicyclic (meth) acrylate in the presence of a polymer containing 50 to less than 100 mol% of the cationic monomer, and d) a combination of these three methods. And the like.

When the cationic substance is added, the amount is preferably 1 to 20 parts by weight based on 100 parts by weight of the polymer or copolymer. This is because the print density is reduced by using more than 20 parts by weight.

The polymerization or copolymerization can be carried out by a known polymerization method, but it is preferable to use emulsion polymerization since a cationic surfactant or a cationic monomer is used.

The polymer of the present invention can be produced by polymerizing the above-mentioned monomer by a known method, and if necessary, a chain transfer agent, a reducing agent, a cross-linking agent and the like can be used. is there.

The additive for ink jet recording used in the present invention may be applied to a support alone without being mixed or blended with a pigment in order to prevent deterioration of water resistance, light fastness and electrophotographic suitability of ink jet recording. preferable.

In the present invention, the support for the recording material may be any suitable for ink-jet recording, and typical examples thereof include paper. Other examples include cloth and polyethylene terephthalate used for overhead projectors. Various resin films such as a resin film can also be used.

The additive for ink jet recording used in the present invention is 0.05 to 2.5 g / m ² , preferably 0.1 to 1.5 g / m ² as a solid content as a coating amount or impregnation amount with respect to the support. ² , sufficient print density is developed. As a coating method, a conventional method can be used as it is.
That is, a size press, a gate roll coater, a blade coater, a bar coater, a spray and the like can be used.

[0030]

The reason why the additive for ink jet recording of the present invention exerts an excellent effect on the color development of a recorded image in ink jet recording is not clear, but it is generally considered as follows. The dispersion obtained by polymerizing the alicyclic (meth) acrylic acid ester of the present invention acts as an organic filler, adsorbs the colorant in the water-soluble ink well, and has a hydrophilic property so that it can absorb the water-soluble ink. Excellent in nature. Also, since many of the colorants used in water-soluble inks for ink jet recording are anionic dyes, by making the ink jet recording additives of the present invention cationic, the dyes are incorporated into the polymer and bonded, Can be fixed. For these reasons, it is considered that the additive for inkjet recording of the present invention is excellent in the color developability of a recorded image in inkjet recording.

[0031]

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

Example 1 In a reactor equipped with a stirrer and a reflux condenser, 95.3 g of cyclohexyl methacrylate, 4.7 g of N, N-dimethylaminoethyl methacrylate, a cationic surfactant (trade name: Katiogen L, trade name: 8.3 made by Ichi Kogyo Seiyaku Co., Ltd.)
g, 327.9 g of ion-exchanged water, 2.3 g of sulfuric acid, and 0.5 g of 2-mercaptoethanol, and the mixture was heated with stirring while blowing in nitrogen gas and dissolved in 50 g of water when the temperature reached 60 ° C. 1.0 g of an initiator (2,2′-azobis (2-amidinopropane) dihydrochloride, manufactured by Wako Pure Chemical Industries, Ltd.) was added, and the mixture was kept at 70 to 75 ° C. for 3 hours. The obtained additive was a white emulsion having an average particle diameter of 116 nm.

Example 2 In a reactor equipped with a stirrer and a reflux condenser, 9.4 g of N, N-dimethylaminoethyl methacrylate, a cationic surfactant (trade name: Katiogen L, Daiichi Kogyo Seiyaku Co., Ltd.)
8.3 g, ion-exchanged water 325.5 g, sulfuric acid 4.6
9 g and 0.5 g of 2-mercaptoethanol were added, and the mixture was heated while being blown and stirred with nitrogen gas, and when the temperature reached 60 ° C., the polymerization initiator (2, 2 ′) dissolved in 50 g of water.
1.0 g of azobis (2-amidinopropane) dihydrochloride, manufactured by Wako Pure Chemical Industries, Ltd.
It was kept at 5 ° C. for 3 hours. After cooling to 50 ° C., 90.6 g of cyclohexyl methacrylate was added, and the mixture was heated while being blown with nitrogen gas and stirred, and when the temperature reached 60 ° C., a polymerization initiator (2,2′-) dissolved in 50 g of water. Add 1.0 g of azobis (2-amidinopropane) dihydrochloride (manufactured by Wako Pure Chemical Industries, Ltd.) and add 3 g at 70 to 75 ° C.
Incubated for hours. The resulting additive has an average particle size of 189 nm.
Was a white emulsion.

Example 3 In a reactor equipped with a stirrer and a reflux condenser, 58.0 g of cyclohexyl methacrylate, 28.8 g of styrene, and acrylamidopropyltrimethylammonium chloride 1 were added.
4.3 g, 8.3 g of a cationic surfactant (trade name: Katiogen L, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), 324.7 g of ion-exchanged water, 5.43 g of sulfuric acid, and 0.5 g of 2-mercaptoethanol were added. When the temperature reached 60 ° C. by blowing while stirring and blowing in nitrogen gas, a polymerization initiator (2,2′-azobis (2-amidinopropane) dihydrochloride dissolved in 50 g of water, Wako Pure Chemical Industries, Ltd. )
1.0 g was added and the mixture was kept at 70 to 75 ° C for 3 hours. The obtained additive was a white emulsion having an average particle diameter of 100 nm.

COMPARATIVE EXAMPLE 2 In a reactor equipped with a stirrer and a reflux condenser, 95.2 g of methyl methacrylate, 4.9 g of N, N-dimethylaminoethyl methacrylate, a cationic surfactant (trade name: Katiogen L, Daiichi 16.7 g, manufactured by Kogyo Seiyaku Co., Ltd.), 318.1 g of ion-exchanged water, 3.73 g of sulfuric acid, and 0.5 g of 2-mercaptoethanol were added, and the mixture was heated to a temperature of 70 to 75 ° C. while blowing and stirring with nitrogen gas. At that time, 1.0 g of a polymerization initiator (2,2′-azobis (2-amidinopropane) dihydrochloride, manufactured by Wako Pure Chemical Industries, Ltd.) dissolved in 50 g of water was added, and the mixture was heated at 70 to 75 ° C. for 3 hours. Incubated for hours. The obtained additive was a white emulsion having an average particle diameter of 257 nm.

Comparative Example 3 In a reactor equipped with a stirrer and a reflux condenser, 18.8 g of cyclohexyl methacrylate, 81.4 g of N, N-dimethylaminoethyl methacrylate, a cationic surfactant (trade name: Katiogen L, trade name: (Ichi Kogyo Seiyaku Co., Ltd.) 16.
7 g, ion-exchanged water 306.9 g, sulfuric acid 15.7 g, 2
-0.5 g of mercaptoethanol was added, and the mixture was heated with stirring while blowing in nitrogen gas, and when the temperature reached 70 to 75 ° C, a polymerization initiator (2, 2′-) dissolved in 50 g of water.
1.0 g of azobis (2-amidinopropane) dihydrochloride, manufactured by Wako Pure Chemical Industries, Ltd.
It was kept at 5 ° C. for 3 hours. The resulting additive has an average particle size of 1
It was a 19 nm white emulsion.

Comparative Example 4 A reactor equipped with a stirrer and a reflux condenser was charged with 70.0 g of acrylamidopropyltrimethylammonium chloride.
259.3 g of ion-exchanged water was added, and the mixture was heated while being blown and stirred with nitrogen gas. When the temperature reached 70 to 75 ° C., the polymerization initiator (2,2′-azobis (2-amidino) dissolved in 50 g of water was used. 1.0 g of propane) dihydrochloride, manufactured by Wako Pure Chemical Industries, Ltd.
Incubated for hours. The resulting additive was a pale yellow clear solution.

Comparative Example 5 Acrylic acid was placed in a reactor equipped with a stirrer and a reflux condenser.
9 g, N, N-dimethylaminoethyl methacrylate 1
9.8 g, 102.4 g of cyclohexyl methacrylate, 16.7 g of sodium dodecylbenzenesulfonate, 315.3 g of ion-exchanged water, 6.55 g of sulfuric acid, and 0.5 g of 2-mercaptoethanol were added, and heated while blowing in nitrogen gas. When the temperature reaches 70 to 75 ° C, water 50
g of a polymerization initiator (2,2′-azobis (2-
1.0 g of amidinopropane) dihydrochloride (manufactured by Wako Pure Chemical Industries, Ltd.) was added, and the mixture was kept at 70 to 75 ° C for 3 hours. The obtained additive was a white emulsion having an average particle diameter of 101 nm.

Example 1 A base paper having a basis weight of 62.2 g / m ² and a Steckigt sizing degree of 0 to 1 second was mixed with a solid concentration of the additive obtained in Example 1 of 3
Weight% aqueous solution using a bar coater to dry solid content 0.7
Coating was performed so as to be 5 g / m ² to prepare a recording medium of the present invention. The inkjet recording suitability of the above recording medium,
Printing was performed using an ink jet printer (BJC-600J, manufactured by Canon Inc.), and evaluation was performed. As an evaluation item, the print density of a solid printed portion of each color was measured by a Gretag reflection densitometer D186. Also, as a water resistance test,
After the printed sample was immersed in ion-exchanged water at 25 ° C. for 15 minutes, the density was measured with a Gretag reflection densitometer D186. The results are shown in Table 1. By applying the additive obtained in Example 1-, the print density was improved and the water resistance was also improved.

Examples 2- to 3- Instead of the additive obtained in Example 1, Example 2-
A recording medium of the present invention was produced in the same manner as in Example 1 except that the additive obtained in Example 3 was used. Evaluation of inkjet suitability was performed in exactly the same manner as in Example 1-. The results are shown in Table 1. The coating density and the water resistance were improved by applying the additives obtained in Example 2 and Example 3-.

Comparative Example 1 The base paper used in Examples 1 to 3 (basis weight: 62.2 g /
m ² , Steckigt sizing degree 0 to 1 second) was used as it was as a comparative example. Table 1 shows the results.

Comparative Examples 2- to 5- Instead of the additive obtained in Example 1, Comparative Example 2-
Example 1 was repeated except that the additives obtained in Examples 1 to 5 were used.
A recording medium was prepared and evaluated in the same manner as described above. Table 1 shows the results.

[0043]

[Table 1]

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C056 FC06 2H086 BA31 BA34 4D075 CA35 DA04 DB18 DC27 EB22 EC35 EC54 4J002 BG041 BG072 BG112 EN136 FD097 FD316

Claims (7)

[Claims] 1. An alicyclic (meth) acrylic acid ester of 5
0 to 100 mol%, a polymer obtained by polymerizing a copolymerizable monomer other than the alicyclic (meth) acrylic acid ester at a ratio of 0 to 50 mol% as an active ingredient, and a cationic ink jet recording additive object. 2. The ink jet recording additive according to claim 1, which comprises a nonionic vinyl monomer as a monomer copolymerizable with the alicyclic (meth) acrylate. 3. The additive for ink jet recording according to claim 1, wherein the copolymerizable monomer contains a cationic monomer in a proportion of 20 mol% or less. 4. An alicyclic (meth) acrylate ester containing 5
As a cationic surfactant and / or a constituent monomer, a polymer obtained by polymerizing a copolymerizable monomer other than the above-mentioned alicyclic (meth) acrylic acid ester at a ratio of 0 to 50 mol% in an amount of 0 to 100 mol%. The additive for inkjet recording according to any one of claims 1 to 3, wherein a polymer containing 50 to 100 mol% of a cationic monomer is mixed. 5. A cationic surfactant and / or 50 to 100 cationic monomers as constituent monomers.
In the presence of a polymer containing mol%, a monomer which can be copolymerized with an alicyclic (meth) acrylate or an alicyclic (meth) acrylate and a compound other than the alicyclic (meth) acrylate described above. The additive for inkjet recording according to any one of claims 1 to 4, which is a polymer obtained by polymerizing 6. A recording medium for ink jet recording, wherein the additive for ink jet recording according to claim 1 is internally added or coated on a support. 7. The method according to claim 1, wherein the pigment is not mixed or blended.
5. A recording medium for ink jet recording obtained by applying only the additive for ink jet recording described in any one of 5 to a support.