JPH09104834A - Production of aqueous pigment dispersion, and aqueous coloring agent composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a finely dispersed aqueous pigment dispersion giving coated products excellent in luster, color generation and coloration, and excellent in fastness and durability such as water resistance, and to obtain an aqueous coloring agent composition containing the aqueous pigment dispersion. SOLUTION: This method for producing an aqueous pigment dispersion comprises (1) a process, (2) a process and a process for crosslinking a resin at an arbitrary time after the aqueous dispersion is produced. The process (1) comprises using a pigment and a resin having carboxyl groups and crosslinking functional groups or self-crosslinking functional groups, neutralizing the carboxyl groups of the resin with a basic compound and subsequently neutralizing or acidifying the aqueous dispersion of the produced hydrophilic resin (B) with an acidic compound to deposit and adhere the resin (B) to the pigment. The process (2) comprises neutralizing the adhered pigment with a basic compound to redisperse the resin (B)-adhered pigment in an aqueous medium. The aqueous coloring agent composition contains this aqueous pigment dispersion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing an aqueous pigment dispersion useful for an aqueous colorant composition such as an aqueous paint, an aqueous ink, a printing agent, a color filter, a jet ink and a color toner.

[0002]

2. Description of the Related Art From the viewpoint of pollution prevention and occupational hygiene, there is a strong tendency toward water-based properties in the industry where colorants such as paints and inks are used.

In order to disperse a pigment used in an aqueous colorant in an aqueous medium, a method of dispersing a powder pigment using a surfactant or a water-soluble resin is common, and is widely used even now. There is. However, a coating material containing a pigment dispersed by using a surfactant has a problem that the obtained coating film has extremely poor water resistance and can be used only for limited applications. Further, it is generally more difficult to disperse the pigment in the aqueous medium containing the water-soluble resin than to disperse the pigment in the organic solvent medium, and the pigment is finely dispersed at a high level, and, It is difficult to keep that state stable.

On the other hand, when the pigment is simply dispersed by using a water-soluble resin, the bond between the pigment and the resin is due only to weak bonding such as adsorption, and even if it is finely dispersed immediately after the production. However, there is a problem that the storage stability is not good because the pigment aggregates with time.

As a method for obtaining an easily dispersible pigment, an acid is added to an aqueous dispersion of a pigment dispersed in a resin having a carboxyl group neutralized with a base to make the resin hydrophobic. There is known a so-called acid precipitation method in which a resin is fixed to a pigment by the method.

For example, a method is known in which rosin is used to adhere to a pigment by an acid precipitation method to obtain a powder pigment having good dispersibility. However, rosin cannot be used as a film-forming resin due to its small molecular weight, and its weather resistance is extremely poor. Therefore, the amount of rosin used cannot be increased, and the amount of rosin used should be about 10% by weight or less. At present, there is no choice but to limit it. Therefore, rosin is currently used in powder pigments as a pigment treating agent, and when used in an aqueous pigment dispersion as in the present invention, a stable aqueous pigment dispersion cannot be obtained by rosin alone. Moreover, there is a problem that the performance of the obtained coating film is low.

In order to solve this problem, Japanese Patent Laid-Open No.
JP-A-122528 and JP-B-61-11979 disclose a method of obtaining a powder or solid pigment by performing acid precipitation using a limited resin such as an acrylic resin having a relatively high molecular weight.

However, in any of these methods, since powdering or solidification occurs after acid precipitation, the pigments agglomerate to some extent in the process, and when used in water-based paints and water-based inks. However, there is a problem that a complicated process of kneading is required again. Moreover, although the powder or solid pigment obtained by these methods is more easily dispersible than the untreated powder pigment, it is a pigment that has been once powdered or solidified and has a high coloring property or high coloring property in an aqueous colorant. There is also a problem that a considerable amount of labor is required to finely disperse the pigment to the extent that it exerts a coloring power.

On the other hand, US Pat. No. 4,166,811 discloses a pigment in which a highly hydrophilic water-soluble resin is used and re-neutralized with a basic compound after acid precipitation to easily disperse in an aqueous medium. Is disclosed.

However, the basic constitution of this method is a method of re-neutralizing with a basic compound, and then pulverizing or solidifying, and when redispersing in an aqueous medium, it is possible to perform only simple stirring. However, once powdered or solidified, the problem of pigment re-aggregation cannot be ignored, and it exhibits the coloring and coloring power of the coating material at a high level. However, there is a problem that simple stirring is not enough. Further, in order to facilitate redispersion in an aqueous medium after pulverization or solidification, the resin which can be used in this method has a low molecular weight and a considerably high acid value, and is applied as a colorant. There is also a problem that the toughness and water resistance of the coating film become extremely low.

[0011]

The film-forming resin used in the aqueous coating agent has physical properties such as the toughness of the coating and
Since durability such as water resistance is important, it is necessary to have a molecular weight above a certain level, and in order not to reduce the water resistance of the obtained coating film, it is effective for dispersing hydrophilic groups such as carboxyl groups and pigment dispersion. It is often designed with a small proportion of various functional groups. Therefore, it has been extremely difficult to finely disperse the pigment at a high level by using the aqueous film-forming resin designed to such a level.

That is, according to the prior art, it was not possible to obtain an aqueous pigment dispersion which can achieve both a high degree of fine dispersion of the pigment and durability such as water resistance of the coated object.

The problem to be solved by the present invention is to provide a coating film which cannot be achieved by the above-mentioned prior art and which is finely dispersed, has good storage stability, and is excellent in water resistance, durability and fastness. It is to provide a method for producing an aqueous pigment dispersion that can be formed.

[0014]

Means for Solving the Invention As a result of intensive studies to solve the above problems, the present inventors have found that a resin having a carboxyl group neutralized with a basic compound and having a crosslinking property is used. The aqueous dispersion of the finely dispersed pigment is strongly fixed to the pigment by making the pH neutral or acidic with an acidic compound to make the resin hydrophobic (hereinafter, this step is referred to as "acid deposition"). Then, a method for producing an aqueous pigment dispersion in which the carboxyl group is neutralized again with a basic compound and redispersed in water, and at any step after obtaining the aqueous dispersion of the pigment. , For example, before acid precipitation,
Simultaneous with acid precipitation, after acid precipitation before redispersion, at the same time as redispersion, or after redispersion, preferably before or after acid precipitation, by crosslinking the resin, gloss to a high level, color development, It is finely dispersed to the extent that it exerts its coloring power, has excellent storage stability, does not have the problem of solvent shock or color separation, and is also excellent in water resistance, durability and fastness of the coated object. Finding that a pigment dispersion can be produced,
The present invention has been completed.

That is, the present invention is as follows: A pigment obtained by using a pigment (A) and a resin (B) having a carboxyl group and a crosslinkable functional group, and neutralizing the carboxyl group of the resin (B) with a basic compound (F1) to make it hydrophilic. Step (1) of precipitating the resin (B) by fixing the aqueous dispersion (1a) of (1a) to neutral or acidic with the acidic compound (E) to fix it to the pigment, and then the resin (B) The step (2) of redispersing the pigment to which the resin (B) is fixed in the aqueous medium by neutralizing the carboxyl group of (1) with the basic compound (F2), and the crosslinking agent ( A method for producing an aqueous pigment dispersion containing C), and at any time after obtaining the aqueous pigment dispersion (1a), the crosslinkable functional group of the resin (B) and the crosslinking agent (C ) Aqueous face characterized by reacting with A method of manufacturing a dispersion,

2. As an aqueous pigment dispersion (1a),
Kneading the pigment (A) and the resin (B) in an organic solvent medium,
Before or after kneading, the cross-linking agent (C) is blended,
Furthermore, before and / or after kneading, at least a part of the carboxyl groups of the resin (B) is neutralized with a basic compound (F1) to disperse it in an aqueous medium to obtain an aqueous pigment. 2. The production method according to 1 above, which uses a dispersion. As an aqueous pigment dispersion (1a), the pigment (A)
An aqueous dispersion of a pigment obtained by mixing and / or kneading a resin (B) having a carboxyl group neutralized with a basic compound (F1) and a crosslinking agent (C) in an aqueous medium is used. The manufacturing method described in 1 above,

4. The resin (B) is a vinyl-based copolymer,
4. The production method according to the above 1, 2, or 3, which is a polyester resin or a polyurethane resin. The acid value based on the carboxyl group of the resin (B) is 3
5. The production method according to the above 1, 2, 3 or 4, in the range of 0 to 120 KOHmg / resin solid content 1 g; The crosslinkable functional group of the resin (B) is a carboxyl group, and the crosslinker (C) is selected from the group consisting of an amino resin and a compound having two or more epoxy groups in the molecule, or the resin (B) 1, 2, 3, wherein the crosslinkable functional group of is a hydroxyl group and the crosslinking agent (C) is an amino resin.
7. The production method according to 4 or 5. Before adding the acidic compound (E) or after redispersing the pigment (A) to which the resin (B) is fixed in an aqueous medium, a crosslinkable functional group of the resin (B) and a crosslinking agent (C) are added. The method according to any one of 1 to 6 above, in which

[8] A pigment (A) and a resin (D) having a carboxyl group and a self-crosslinking functional group are used, and the carboxyl group of the resin (D) is made hydrophilic by neutralizing the carboxyl group with a basic compound (F1). Step (1) of precipitating the resin (D) by fixing the aqueous dispersion (1b) of the pigment with the acidic compound (E) to adjust the pH to neutral or acidic, and then the resin (D). The method for producing an aqueous pigment dispersion, which comprises the step (2) of redispersing the pigment (A) to which the resin (D) is fixed in an aqueous medium by neutralizing the carboxyl group of the above with a basic compound (F2). A method for producing an aqueous pigment dispersion, which comprises self-crosslinking the resin (D) at any time after obtaining the aqueous pigment dispersion (1b),

9. As an aqueous pigment dispersion (1b),
Kneading the pigment (A) and the resin (D) in an organic solvent medium,
Before and / or after kneading, at least part of the carboxyl groups of the resin (D) is a basic compound (F1).
10. The production method according to the above 8, which uses the aqueous dispersion (1b) of the pigment obtained by dispersing in an aqueous medium by neutralizing with. As the aqueous pigment dispersion (1b), the pigment (A) is used.
8. The use of the pigment aqueous dispersion (1b) obtained by mixing and / or kneading a carboxyl group-containing resin (D) with a basic compound (F1) in an aqueous medium. Manufacturing method of

11. 11. The production method according to the above 8, 9 or 10, wherein the resin (D) is a vinyl-based copolymer, a polyester resin or a polyurethane resin. The acid value based on the carboxyl group of the resin (D) is
12. The production method according to the above 8, 9, 10 or 11, which is in the range of 30 to 120 KOHmg / resin solid content 1 g. The self-crosslinking functional group of the resin (D) has (1) a carboxyl group and an epoxy group in one molecule,
(2) The production method according to the above 8, 9, 10, 11 or 12, which has a hydroxyl group and an N-alkoxymethylamide group in one molecule, or (3) is a radically polymerizable unsaturated group. Any one of the above 8 to 13 in which the resin (D) is self-crosslinked before the addition of the acidic compound (E) or after redispersing the pigment (A) to which the resin (D) is fixed in an aqueous medium. Manufacturing method described in

15. An aqueous colorant composition comprising an aqueous pigment dispersion produced by the production method described in any one of 1 to 14 above.

The acid value in the present invention is expressed by the amount of mg of potassium hydroxide necessary to neutralize 1 g of resin solid content.

The production method of the present invention comprises the production method (I) described in 1 to 7 above and the production method (II) described in 8 to 14 above.
The production method (I) basically comprises the following production steps.

Step (I-1): The pigment (A) and the resin (B) having a carboxyl group and a crosslinkable functional group are used, and the carboxyl group of the resin (B) is converted to a basic compound (F).
The aqueous dispersion (1a) of a pigment, which is made hydrophilic by neutralization with 1), is neutralized or acidified with an acidic compound (E) to precipitate a resin (B) and thereby a pigment. Fix to (A). Step (I-2): After the resin (B) is fixed to the pigment (A) by the above step (I-1), the carboxyl group of the resin (B) is neutralized with the basic compound (F2). Then, the pigment (A) to which the resin (B) is fixed is redispersed in an aqueous medium. Step (I-3): The cross-linking agent (C) is blended, and then the cross-linking functional group of the resin (B) and the cross-linking agent ( C) reacts to crosslink.

The production method (II) of the present invention basically comprises the following production steps. -Acidation step (II-1): using the pigment (A) and a resin (D) having a carboxyl group and a self-crosslinking functional group,
The carboxyl group of the resin (D) is replaced with a basic compound (F1)
The aqueous dispersion (1b) of the pigment, which is hydrophilized by neutralization with, is neutralized or acidified to pH with the acidic compound (E) to precipitate the resin (D), and thus the pigment (A ) Fixed to. Step (II-2): After the resin (D) is fixed to the pigment (A) by the above step (II-1), the carboxyl group of the resin (D) is neutralized with the basic compound (F2). Then, the pigment (A) to which the resin (D) is fixed is redispersed in an aqueous medium. Step (II-3): The resin (D) is self-crosslinked at any stage after obtaining the aqueous pigment dispersion (1b).

In the above production methods (I) and (II),
The resin (B) or (D) may be crosslinked at any time after the aqueous pigment dispersion (1a) or (1b) is obtained. For example, the step (I-1) or (II-1) ), After obtaining the aqueous dispersion (1a) or (1b) of the pigment and before adding the acidic compound (E), in the step (I-1) or (II-1), the acidic compound (E) When the resin (B) or (D) is precipitated by using and fixed to the pigment (A), after completion of the step (I-1) or (II-1), the step (I-2) or (II -2), the basic compound (F
Before the addition of 2), in the step (I-2) or (II-2), the pigment (A) to which the resin (B) or (D) is fixed using the basic compound (F2) is re-used in an aqueous medium. When dispersing, the resin (B) is produced by the step (I-2) or (II-2).
Alternatively, it may be after the pigment (A) to which (D) is fixed is redispersed in an aqueous medium. Among these, since a good aqueous pigment dispersion can be obtained, it is preferable to crosslink at the above-mentioned time or, and most preferable to crosslink at the time. Further, there is an advantage that the process can be rationalized if the crosslinking is carried out at the above step or.

If the resin (B) or (D) used in the production method of the present invention has a carboxyl group and a crosslinkable functional group or a self-crosslinkable functional group,
Any resin may be used, for example, vinyl copolymer, polyester resin, polyurethane resin,
Examples thereof include epoxy resin and rosin-modified resin. Among them, vinyl copolymers, polyester resins and polyurethane resins are preferable from the viewpoint of ease of introduction of carboxyl group, ease of introduction of crosslinkable functional group or self-crosslinkable functional group, and toughness of coating film. Is preferred.

Examples of the vinyl copolymer used in the production method of the present invention include (meth) acrylic acid ester resin, (meth) acrylic acid ester-styrene copolymer resin, and styrene- (anhydrous) maleic acid copolymer. Examples thereof include polymer resins and fluorine-containing vinyl copolymer resins.
Examples of the polyester resin used in the production method of the present invention include saturated polyester resin, unsaturated polyester resin, and alkyd resin. These resins contain a carboxy group as a hydrophilic group for imparting appropriate water solubility or water dispersibility, and have a crosslinkable functional group or a self-crosslinkable functional group for crosslinking. Required.

The crosslinkable functional group is a functional group capable of reacting with a crosslinking agent to form a crosslink, and the self-crosslinkable functional group is a functional group having self-crosslinkability and a crosslinkable functional group. is there.

Examples of the crosslinkable functional group include a carboxyl group, a hydroxyl group, a tertiary amino group, a blocked isocyanate group, an epoxy group, and a 1,3-dioxolan-2-on-4-yl group.

Next, examples of typical combinations of the crosslinkable functional group and the crosslinking agent (C) are listed below. (A) When the crosslinkable functional group is a carboxyl group, the crosslinking agent (C) is an amino resin, a compound having two or more epoxy groups in one molecule, and 1,3-dioxolan-2-one in one molecule. Examples thereof include compounds having two or more -4-yl groups (also referred to as cyclocarbonate groups). When the crosslinkable functional group (b) is a hydroxyl group, examples of the crosslinking agent (C) include amino resins, polyisocyanate compounds and blocked polyisocyanate compounds. (C) When the crosslinkable functional group is a tertiary amino group, the crosslinking agent (C) is a compound having two or more epoxy groups in one molecule and 1,3-dioxolan-2-one in one molecule. Examples thereof include compounds having two or more -4-yl groups. When the crosslinkable functional group (d) is a blocked isocyanate group, examples of the crosslinking agent (C) include compounds having two or more hydroxyl groups in one molecule. (E) When the crosslinkable functional group is an epoxy group or a 1,3-dioxolan-2-one-4-yl group, the crosslinking agent (C) is a compound having two or more carboxyl groups in one molecule, or a polyamine. Examples thereof include compounds and polymercapto compounds.

Examples of the self-crosslinkable functional group include radically polymerizable unsaturated groups and hydrolyzable alkoxysilane groups. For the purpose of reinforcing the self-crosslinking property, a compound having two or more radically polymerizable unsaturated groups and a compound having a hydrolyzable alkoxysilane group can be partially used in combination.

The functional group capable of cross-linking has two or more kinds of functional groups capable of reacting together in one molecule. Examples of the combination of such functional groups include (a) a carboxyl group and an epoxy group, ( b) carboxyl group and 1,3-dioxolan-2-on-4-yl group, (c) hydroxyl group and blocked isocyanate group, (d) hydroxyl group and N-alkoxymethylamide group, (e) hydroxyl group and hydrolyzable Combinations of alkoxysilane groups, and the like are included.

Next, a specific method for introducing a crosslinkable and self-crosslinkable functional group into the resin will be described.

The vinyl-based copolymer in which the hydrophilic group and the crosslinkable functional group are carboxyl groups can be easily produced by a method of copolymerizing a polymerizable monomer composition containing a polymerizable monomer having a carboxyl group. it can. Examples of the polymerizable monomer having a carboxyl group include acrylic acid, methacrylic acid, crotonic acid, fumaric acid, itaconic acid, (anhydrous) maleic acid, monoalkyl maleates such as monobutyl maleate, and itacone such as monobutyl itaconate. Examples thereof include acid monoalkyls.

As the polymerizable vinyl monomer other than the polymerizable vinyl monomer having a carboxyl group contained in the polymerizable monomer composition, for example, aromatic vinyl monomers such as styrene, vinyltoluene and α-methylstyrene; methyl ( (Meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, isoamyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isodecyl (meth) Acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, butoxymethyl (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, benzyl (meth) (Meth) acrylic acid esters such as acrylate, cetyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate and isobornyl (meth) acrylate; vinyl esters such as vinyl acetate, vinyl benzoate, vinyl versatate, vinyl propionate Polymerizable nitriles such as (meth) acrylonitrile; Vinyl monomers having a fluorine atom such as vinyl fluoride, vinylidene fluoride, tetrafluoroethylene, hexafluoropropylene or chlorotrifluoroethylene; diethylaminoethyl (meth) acrylate, dimethyl Tertiary amino group-containing monomers such as aminoethyl (meth) acrylate, N-vinylimidazole, N-vinylcarbazole; 2- (2'-hydroxy-5-methacryloyloxyethyl) Eniru)
-2H-benzotriazole, 2-hydro-4- (2
-Methacryloyloxyethoxy) benzophenone,
Monomers having ultraviolet absorption or antioxidant properties such as 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate; N-vinylpyrrolidone, glycidyl (meth) acrylate, 1,3-dioxolan-2-one N-alkoxymethyl (meth) such as -4-ylmethyl (meth) acrylate, 1,3-dioxolan-2-one-4-ylmethyl vinyl ether, diacetone acrylamide, N-methylol acrylamide, N-butoxymethyl (meth) acrylamide. ) Functional group-containing monomers such as acrylamides; phosphoric acid group-containing monomers such as 2-phosphooxyethyl (meth) acrylate and 4-phosphooxybutyl (meth) acrylate; having one polymerizable unsaturated group at the molecular end Examples thereof include macromonomers.

As the method for polymerizing the polymerizable vinyl monomer composition, various known polymerization methods such as suspension polymerization, emulsion polymerization, bulk polymerization and solution polymerization can be used, but solution polymerization is preferred because it is simple. As the polymerization initiator, known peroxides and azo compounds can be used.

The vinyl copolymer having a carboxyl group is obtained by adding a maleic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, trimellitic anhydride to a vinyl copolymer having a hydroxyl group described below. It can also be produced by a method of performing an addition reaction with an anhydrous acid such as.

The vinyl copolymer having a hydroxyl group and a carboxyl group can be easily produced by using a polymerizable monomer having a hydroxyl group in combination with the above-mentioned vinyl copolymer having a carboxyl group. . As the polymerizable monomer having a hydroxyl group, for example,
2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, "Praxel FM-
2 ”and“ Placcel FA-2 ”(manufactured by Daicel Chemical Industries, Ltd.) added (meth) acrylic monomers, polyethylene glycol mono (meth) acrylate monomers, polypropylene glycol mono (meth) acrylate. Examples thereof include monomers, hydroxyethyl vinyl ether and hydroxybutyl vinyl ether.

For the vinyl-based copolymer having a tertiary amino group and a carboxyl group, a polymerizable monomer having a tertiary amino group should be used in combination when the vinyl copolymer having a carboxyl group described above is produced. Can be easily manufactured. As the polymerizable monomer having a tertiary amino group, for example, diethylaminoethyl (meth)
Examples thereof include acrylate and dimethylaminoethyl (meth) acrylate.

The vinyl copolymer having a blocked isocyanate group and a carboxyl group can be easily prepared by using a polymerizable monomer having a blocked isocyanate group in combination during the production of the above vinyl copolymer having a carboxyl group. It can be manufactured.

The polymerizable monomer having a blocked isocyanate group can be easily obtained by adding a known blocking agent to a polymerizable monomer having an isocyanate group such as 2-methacryloyloxyethyl isocyanate. Alternatively, it can be easily produced by subjecting a vinyl copolymer having a hydroxyl group and a carboxyl group to an addition reaction with a compound having an isocyanate group and a blocked isocyanate group.

The compound having an isocyanate group and a blocked isocyanate group can be easily obtained by addition-reacting a diisocyanate compound with a known blocking agent in a molar ratio of about 1: 1.

The vinyl copolymer having an epoxy group and a carboxyl group can be easily produced by using a polymerizable monomer having an epoxy group in combination when producing the above-mentioned vinyl copolymer having a carboxyl group. You can Examples of the polymerizable monomer having an epoxy group include glycidyl (meth) acrylate and a (meth) acrylate monomer having an alicyclic epoxy group.

The vinyl copolymer having a 1,3-dioxolan-2-on-4-yl group and a carboxyl group is a 1,3-dioxolane at the time of producing the above-mentioned vinyl copolymer having a carboxyl group. -2-on-4-
It can be easily produced by using a polymerizable monomer having an yl group in combination. 1,3-dioxolane-2
As the polymerizable monomer having a -on-4-yl group,
For example, 1,3-dioxolan-2-on-4-ylmethyl (meth) acrylate, 1,3-dioxolane-2
Examples include-on-4-ylmethyl vinyl ether.

A vinyl-based copolymer having a polymerizable unsaturated group and a carboxyl group, which are self-crosslinking functional groups, can be obtained, for example, by adding (a) a vinyl-based copolymer having an epoxy group and a carboxyl group to a tertiary amino group. A method of subjecting a polymerizable monomer having a group to an addition reaction, and (b) a vinyl-based copolymer having a hydroxyl group and a carboxyl group, a polymerizable monomer having an isocyanate group such as 2-methacryloyloxyethyl isocyanate, or maleic anhydride. It is easily produced by a method in which an acid anhydride having a polymerizable unsaturated group such as, for example, is subjected to an addition reaction, and (c) a vinyl-based copolymer having a carboxyl group is subjected to an addition reaction with a polymerizable monomer having an epoxy group. be able to.

The vinyl-based copolymer having a cross-reactive functional group and a carboxyl group is (a) a polymerizable monomer having an epoxy group, (b) when the above-mentioned vinyl copolymer having a carboxyl group is produced. A polymerizable monomer having a 1,3-dioxolan-2-on-4-yl group,
Cross-reactivity such as a combination of (c) a polymerizable monomer having a hydroxyl group and a polymerizable monomer having a blocked isocyanate group, and (d) a polymerizable monomer having a hydroxyl group and a polymerizable monomer having an N-alkoxymethylamide group. It can be easily produced by copolymerizing a polymerizable monomer having a functional group.

The polyester resin in which the hydrophilic group and the crosslinkable functional group are carboxyl groups is prepared by subjecting the carboxyl group-containing compound and the hydroxyl group-containing compound to a known method such as a melting method or a solvent method so that the carboxyl group remains. It is produced by performing a dehydration condensation reaction.

The polyester resin is a compound having a carboxyl group such as a monobasic acid, a dibasic acid or a polybasic acid,
The alkyd resin is obtained by appropriately selecting and dehydrating and condensing a compound having a hydroxyl group such as a diol or a polyol, and further using an oil or a fatty acid.

The carboxyl group contained in the polyester resin used in the production method of the present invention is an unreacted carboxyl group mainly derived from the dibasic acid or polybasic acid constituting the polyester resin.

Examples of the dibasic acid or polybasic acid include adipic acid, (anhydrous) succinic acid, sebacic acid, dimer acid, (anhydrous) maleic acid, (anhydrous) phthalic acid, isophthalic acid, terephthalic acid, tetrahydro ( Anhydrous) phthalic acid, hexahydro (anhydrous) phthalic acid, hexahydroterephthalic acid, 2,6-naphthalenedicarboxylic acid, (anhydrous)
Examples thereof include trimellitic acid and (anhydrous) pyromellitic acid.

Examples of the compound having a carboxyl group other than the dibasic acid or the polybasic acid include lower alkyl esters of acids such as dimethyl terephthalate;
Benzoic acid, p-tert-butylbenzoic acid, monobasic acids such as rosin and hydrogenated rosin; fatty acids and oils and fats; macromonomers having 1 or 2 carboxyl groups at the molecular ends; 5-sodium sulfoisophthale Examples thereof include acids and their dimethyl esters.

Examples of the compound having a hydroxyl group include:
Ethylene glycol, neopentyl glycol, propylene glycol, diethylene glycol, dipropylene glycol, 2-methyl-1,3-propanediol,
2,2-diethyl-1,3-propanediol, 1,4
-Butanediol, 1,3-propanediol, 1,6
-Hexanediol, 1,4-cyclohexanedimethanol, 1,5-pentanediol, alkylene oxide adduct of bisphenol A, hydrogenated bisphenol A,
Hydrogenated bisphenol A alkylene oxide adduct,
Polyethylene glycol, polypropylene glycol,
Diols such as polytetramethylene glycol; polyols such as glycerin, trimethylolpropane, trimethylolethane, diglycerin, pentaerythritol, trishydroxyethyl isocyanurate;
Examples thereof include monoglycidyl compounds such as "CARDURA E-10" (glycidyl ester of synthetic fatty acid manufactured by Shell Chemical Co., Ltd.) and macromonomers having two hydroxyl groups at one end of the molecule.

When synthesizing the polyester resin,
Castor oil, hydroxyl group-containing fatty acids such as 12-hydroxystearic acid or fats and oils; dimethylolpropionic acid, p
Compounds having a carboxyl group and a hydroxyl group such as -hydroxybenzoic acid; cyclic ester compounds such as ε-caprolactone can also be used.

Further, a part of the dibasic acid can be replaced with a diisocyanate compound.

Further, the polyester resin having a carboxyl group is obtained by adding maleic anhydride, phthalic anhydride, tetrahydrophthalic anhydride to polyester resin having a hydroxyl group.
It can also be produced by a method in which an anhydride such as hexahydrophthalic anhydride or trimellitic anhydride is subjected to an addition reaction.

The polyester resin having a hydroxyl group and a carboxyl group can be easily produced by reacting the polyester resin in a dehydration condensation reaction according to a known method so that the hydroxyl group and the carboxyl group remain.

Polyester resins having a tertiary amino group and a carboxyl group are triethanolamine, N-
A compound having a tertiary amino group and a hydroxyl group such as methyldiethanolamine and N, N-dimethylethanolamine can be easily produced by using it as an alcohol component when producing a polyester resin.

The polyester resin having a polymerizable unsaturated group which is a self-crosslinkable functional group and a carboxyl group is
(A) Polymerizable monomers having an isocyanate group such as 2-methacryloyloxyethyl isocyanate in a polyester resin having a hydroxyl group and a carboxyl group,
Alternatively, a method of subjecting an anhydride having a polymerizable unsaturated group such as maleic anhydride to an addition reaction, (b) a method of subjecting a polyester resin having a carboxyl group to an addition reaction of polymerizable monomers having an epoxy group as described above,
(C) A method of synthesizing a polyester by using a polymerizable unsaturated group such as maleic anhydride as an acid component, can be easily produced.

The polyurethane resin having a carboxyl group used in the production method of the present invention comprises a polyol component containing a compound having a carboxyl group and a hydroxyl group such as dimethylolpropionic acid as a component for introducing a carboxyl group, and a polyisocyanate component. It can be easily produced by reacting with.

As the polyol component, in addition to the diol component listed in the method for producing a polyester, a trifunctional or higher functional polyol compound may be used, if necessary.

The polyisocyanate component includes 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, phenylene diisocyanate, 1,5-naphthalene diisocyanate,
Metaxylylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated 4,
In addition to diisocyanate compounds such as 4'-diphenylmethane diisocyanate, hydrogenated metaxylylene diisocyanate and crude 4,4'-diphenylmethane diisocyanate, polyisocyanate compounds such as polymethylene polyphenyl isocyanate can be used.

The polyurethane resin may be produced by a conventional method. For example, it is preferable to carry out the addition reaction at room temperature or at a temperature of about 40 to 100 ° C. in an inert organic solvent solution that does not react with the isocyanate group. At that time, a known catalyst such as dibutyltin dilaurate may be used.

In the reaction system for producing the polyurethane resin, known chain extenders such as diamines, polyamines, N-alkyl dialkanol amines such as N-methyl diethanol amine; dihydrazide compounds and the like can be used.

The polyurethane resin having a hydroxyl group and a carboxyl group can be easily produced by reacting the polyurethane resin at a ratio of more hydroxyl groups than isocyanate groups when producing a polyurethane resin. Alternatively, it can also be easily produced by subjecting a polyisocyanate resin having a carboxyl group and a terminal isocyanate group to an addition reaction with a compound having two or more hydroxyl groups in one molecule.

A polyurethane resin having a tertiary amino group and a carboxyl group has N as a part of the polyol component.
It can be easily prepared by using an N-alkyl dialkanol amine such as -methyl diethanol amine.

The polyurethane resin having a blocked isocyanate group and a carboxyl group can be easily produced by adding a known blocking agent to a polyisocyanate resin having a carboxyl group and a terminal isocyanate group.

The polyurethane resin having an epoxy group and a carboxyl group can be easily produced by adding a compound having a hydroxyl group and an epoxy group to a polyisocyanate resin having a carboxyl group and a terminal isocyanate group.

Examples of the compound having a hydroxyl group and an epoxy group include glycidol, glycerin diglycidyl ether, trimethylolpropane diglycidyl ether, and bisphenol A diglycidyl ether.

The polyurethane resin having a polymerizable unsaturated group which is a self-crosslinkable functional group and a carboxyl group is a polyisocyanate resin having a terminal isocyanate group,
A polymerizable monomer having a hydroxyl group as described above and a compound having a hydroxyl group and a polymerizable unsaturated group such as glycerol mono (meth) acrylate, trimethylolpropane di (meth) acrylate, or pentaerythritol triacrylate are added. It can be easily produced by a reaction method or the like.

The polyurethane resin having a hydrolyzable alkoxysilane group and a carboxyl group of the self-crosslinking functional group is a polyisocyanate resin having a terminal isocyanate group, γ-mercaptopropyltrimethoxysilane,
γ-mercaptopropylmethyldimethoxysilane, γ-
It can be easily produced by a method in which a silane coupling agent having an active hydrogen capable of reacting with an isocyanate group such as aminopropyltrimethoxysilane and γ-aminopropyltriethoxysilane is subjected to an addition reaction.

The amount of carboxyl groups in the resin (B) having a carboxyl group and a crosslinkable functional group or the resin (D) having a carboxyl group and a self-crosslinking functional group is such that the acid value is in the range of 30 to 120. Is preferably 50 to 10
An amount in the range of 0 is more preferable. If the acid value exceeds 120, the hydrophilicity tends to be too high, so that the water resistance of the coated article tends to be remarkably reduced. If the acid value is less than 30, acid precipitation causes water to be neutralized. It is not preferable because the redispersibility in water tends to decrease.

Resin (B) having a carboxyl group and a crosslinkable functional group or a self-crosslinkable functional group used in the present invention
Alternatively, when the resin (D) is a vinyl-based copolymer or a polyurethane resin, the number average molecular weight is 5,000 to 2
Those in the range of 10,000 are preferable. If the number average molecular weight is lower than 5,000, the coated object tends to become brittle when used in a coating agent, and the number average molecular weight is 2 or more.
When it is higher than 10,000, it tends to be difficult to obtain a fine pigment dispersion, which is not preferable.

Resin (B) having a carboxyl group and a crosslinkable functional group or a self-crosslinkable functional group used in the present invention
Alternatively, when the resin (D) is a polyester resin,
Since the molecular weight is mostly branched polyester resin, unlike the case of linear vinyl copolymers, the weight average molecular weight is large even if the number average molecular weight is small, so it has sufficient toughness as a film. Have. Therefore, the number average molecular weight of the polyester resin is 1,000 to
Those having a weight average molecular weight of 20,000 are preferable, and those having a weight average molecular weight of 5,000 to 100,000 are preferable.

The pigment (A) used in the present invention may be an inorganic pigment or an extender pigment, but carbon black or an organic pigment is particularly preferable.

Typical organic pigments include, for example, phthalocyanine blue, phthalocyanine green,
Phthalocyanine series such as Hansa Yellow and permanent red, anthraquinone series, perinone series, dioxazine series, perylene series, quinacridone series, azo series metal complex, methine series metal complex, thioindigo series, isoindolinone series, isoindoline series, slene series, Examples include diaminoanthraquinonyl series.

The pigment used in the present invention may be a powder or a solidified pigment, or a pigment dispersed in water such as an aqueous slurry or a press cake can be used.

Next, the manufacturing steps in the present invention will be described in order.

First, in the step of mixing or kneading the pigment with the resin (B) or resin (D) having a carboxyl group and a crosslinkable functional group or a self-crosslinkable functional group, the following two methods are suitable. (1) A method in which a resin and a pigment are kneaded in an organic solvent medium and then dispersed in an aqueous medium. (2) A method of mixing or kneading pigments in an aqueous medium.

In the method (1), in order to knead a resin and a pigment in an organic solvent, first, a powder or solid pigment and an organic solvent solution of the resin are knoWn in a knoWn ball mill, a sand mill, a colloid mill or the like. Finely knead using a disperser.

As the organic solvent used in the first method (1), all of the commonly used organic solvents can be used, but the solubility in the resin is good, there is no problem in the synthesis of the resin, and the vapor pressure is higher than that of water. It is preferable that the solvent can be easily removed, and that the solvent is miscible with water. Examples of such an organic solvent include acetone, methyl ethyl ketone, methanol, ethanol, n-propanol, isopropanol, ethyl acetate, tetrahydrofuran and the like. Further, although it has low miscibility with water, methyl isopropyl ketone, methyl-n-propyl ketone, isopropyl acetate, n-propyl acetate, methylene chloride, benzene and the like can also be used.

To disperse a dispersion of an organic solvent, a resin and a pigment in an aqueous medium, the carboxyl group of the resin is neutralized with a basic compound (F1) to make the resin hydrophilic in water. Can be dispersed in.

The following method is suitable for the dispersion method in water. (A) A method in which a dispersion comprising an organic solvent, a pigment and a resin is neutralized with a basic compound and then water is added dropwise. (B) A method of adding water dropwise to a dispersion composed of a resin neutralized with an organic solvent, a pigment and a basic compound. (C) A method of dropping water containing a basic compound into a dispersion composed of an organic solvent, a pigment and a resin. (D) A dispersion comprising an organic solvent, a pigment and a resin is neutralized with a basic compound and then added to an aqueous medium. (E) A dispersion composed of a resin neutralized with an organic solvent, a pigment and a basic compound is added to an aqueous medium. (F) A dispersion composed of an organic solvent, a pigment and a resin is added to an aqueous medium containing a basic compound.

When dispersed in water, it may be carried out by usual stirring with low shear, stirring with high shear by a homogenizer, or using ultrasonic waves. Further, for the purpose of assisting dispersion in an aqueous medium, a surfactant, a protective colloid or the like can be used together within a range that does not significantly reduce the water resistance of the coated object.

Examples of the basic compound (F1) include:
Inorganic bases such as sodium hydroxide and potassium hydroxide, ammonia, triethylamine, tributylamine, dimethylethanolamine, diisopropanolamine and organic amines such as morpholine can be used.

In the second method (2), in order to knead the resin and the pigment in an aqueous medium, first, the carboxyl group of the resin is neutralized with the basic compound (F1) as described above, and then the aqueous solution is prepared. Mix or knead with pigment in medium. At this time, the resin dissolved or dispersed in water may contain an organic solvent, or the solvent may be removed to be a medium containing substantially only water. As the pigment, any of a powder pigment, an aqueous slurry and a press cake can be used. In the dispersion in an aqueous medium, it is preferable to use an aqueous slurry or presscake in which secondary aggregation of pigment particles is small in order to simplify the manufacturing process. Kneading method, organic solvent,
The basic compound (F1) may be the same as and used for the dispersion in the organic solvent medium.

A basic compound (F1) for hydrophilicizing the resin (B) or the resin (D) having a carboxyl group and a crosslinkable functional group or a self-crosslinkable functional group.
Neutralization of the carboxyl group by means of making the resin hydrophilic more than the extent that the resin becomes hydrophilic and an aqueous pigment dispersion (1a) or (1b) is obtained, and all the carboxyl groups in the resin are neutralized. There is no need to harmonize. Usually, about 50 to 100 mol% of the carboxyl groups in the resin are neutralized.

Whether kneading with an organic solvent system or an aqueous system, a pigment dispersant and a wetting agent are used together within a range that does not reduce the water resistance of the coated object for the purpose of assisting the dispersion of the pigment. You can also

When the pigment is kneaded or after the kneading,
It is also possible to add substances other than pigments, for example, dyes, antioxidants, ultraviolet absorbers, crosslinking catalysts for coating binders, rust preventives, fragrances, chemicals and the like.

The ratio of the resin to the pigment is preferably 1 to 200 parts by weight, and particularly preferably 5 to 100 parts by weight, based on 100 parts by weight of the pigment, as the solid content of the resin. If the proportion of resin solids is less than 1 part by weight, it tends to be difficult to disperse the pigment in a sufficiently fine manner, and if it is more than 200 parts by weight, the proportion of the pigment in the dispersion becomes small, and the coating agent It is not preferable because it tends to run out of composition design margin when used for such purposes.

The acid precipitation carried out for the purpose of strongly fixing the resin to the pigment finely dispersed in the aqueous medium is carried out by adding the acid compound (E) to the carboxyl group neutralized by the basic compound (F1). It is carried out by making the resin hydrophobic by making the pH neutral or acidic. Examples of the acidic compound (E) used include inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid and nitric acid; organic acids such as formic acid, acetic acid and propionic acid. An inorganic acid such as hydrochloric acid, which has a large acidifying effect, is preferable. The pH is preferably in the range of 3 to 6, but some pigments are decomposed by an acid, and in the case of such a pigment, acid precipitation can be performed in the range of pH 4 to 7. However, when the resin or the cross-linking agent has an epoxy group, hydrochloric acid or organic acid reacts with the epoxy group, and therefore it is not preferable to use it as an acidic compound. In such a case, phosphoric acid or the like can be preferably used. Also 5
About 7 is preferable. It is also preferable to remove the organic solvent present in the system by vacuum distillation or the like before carrying out the acid precipitation.

After acid precipitation, if necessary, filtration and washing with water are carried out to produce a water-containing cake of dispersed pigments. For the filtration, known methods such as suction filtration, pressure filtration, and centrifugal separation can be adopted.

This water-containing cake was dried without being dried.
By re-neutralizing the carboxyl group using the basic compound (F2) in the water-containing state, the pigment particles are re-dispersed in the aqueous medium while maintaining the fine state without agglomeration. The basic compound (F2) is preferably a volatile amine compound such as ammonia, triethylamine or dimethylethanolamine in consideration of the water resistance of the object to be coated.

Next, the crosslinking in the present invention will be described.

When the crosslinking is self-crosslinking, the aqueous dispersion before acid precipitation, the water-containing cake after acid precipitation, and the basic compound (F
Crosslinking may be carried out in any state of the aqueous dispersion re-neutralized in 2), but crosslinking in the state of the aqueous dispersion before acid precipitation or the aqueous dispersion after re-neutralization is preferable. Crosslinking in the state of the aqueous dispersion after the addition is more preferable.

Self-crosslinking by a carboxyl group and an epoxy group, self-crosslinking by a hydroxyl group and an N-alkoxymethylamide group, and self-crosslinking by a hydrolyzable alkoxysilane group can be carried out under the conditions as described above, and the crosslinking can be carried out more quickly. To do so, a crosslinking catalyst can be used as appropriate.

In the case of self-crosslinking with a radically polymerizable unsaturated group, a water-soluble polymerization initiator such as potassium persulfate or ammonium persulfate is added, and the polymerization is performed at a redox system at 50 to 90 ° C. It can be crosslinked at moderate temperatures.

On the other hand, when the cross-linking is carried out using the cross-linking agent (C), the composition of the cross-linking agent is such that the resin to be used, the aqueous dispersion before acid precipitation, the water-containing cake after acid precipitation, and the base It can be added to any of the aqueous dispersions re-neutralized with the acidic compound (F2), and the crosslinking is also performed with the aqueous dispersion before acid precipitation, the water-containing cake after acid precipitation, and the aqueous dispersion after re-neutralization. It can be crosslinked in any of the above conditions. However, in order to obtain a finer aqueous dispersion of the pigment, it is preferable to use the following crosslinking agent, compounding method and crosslinking method.

As the cross-linking agent (C), any one may be used which is infinitely soluble in water, has appropriate hydrophilicity, or is completely hydrophobic. A completely hydrophobic resin can be incorporated into particles by mixing with a resin (B) having a carboxyl group and a crosslinkable functional group and dispersing it in water.

Among these cross-linking agents (C), preferable cross-linking agents are those which are not infinitely soluble in water, are not completely hydrophobic, and have appropriate hydrophilicity. Is mentioned. For those that are infinitely soluble in water, since the crosslinking agent is partially dissolved in the aqueous medium, crosslinking between dispersed particles cannot be ignored, and there is a risk that coarse particles will be generated, and completely. The hydrophobic one cannot be well dispersed in the aqueous medium, and there is a risk that coarse particles are generated. The hydrophilicity of the crosslinking agent (C) in the present invention is
Those having a water tolerance of 10 to 2,000% are preferable, and those having a water tolerance of 20 to 1,000% are more preferable.

The water tolerance is based on the following measurement.

5 g of the resin solution was weighed into a 100 cc Erlenmeyer flask, and ion-exchanged water was added dropwise while stirring at 25 ° C. The amount of water dropped when the solution became cloudy and the newspaper characters could not be read was measured with respect to the resin. Expressed in%. For example, when the amount of ion-exchanged water is 10 cc, the water tolerance is 200%.

The step of adding the cross-linking agent (C) is preferably added to the resin solution to be used before kneading with the pigment. With a mixed solution of a resin (B) solution and a crosslinking agent (C),
Even when the pigment (A) is kneaded with an organic solvent system and then dispersed in water, or when the mixed solution is dispersed in water and then the pigment (A) is kneaded, the crosslinking agent (C ) Is encapsulated by the resin (B) and is dispersed in water, and since crosslinking occurs exclusively inside the particles, coarse particles are not generated.

The time of crosslinking may be any time after obtaining the aqueous dispersion (1a) of the pigment as described above, but before the addition of the acidic compound (E) for the acid precipitation or the re-neutralization. Subsequent crosslinking in the aqueous dispersion is preferred, and crosslinking in the aqueous dispersion after re-neutralization is most preferred.

The crosslinking is preferably carried out by heating at 50 to 100 ° C. under normal pressure, but in some cases, 100 to 1 under pressure.
It can also be crosslinked at about 50 ° C. The use of crosslinking catalysts can also be recommended.

Examples of the cross-linking agent (C) include amino resins and compounds having two or more epoxy groups in the molecule.

Amino resins include melamine resins, urea resins,
A typical example is benzoguanamine resin, which is methylolated with formaldehyde and then etherified with methanol or butanol.

Compounds having two or more epoxy groups are various polyglycidyl ethers called epoxy resins,
Examples thereof include vinyl-based copolymers obtained by copolymerizing polyglycidyl esters and a polymerizable monomer having an epoxy group such as glycidyl methacrylate.

The blending ratio of the resin (B) and the crosslinking agent (C) is preferably 50:50 to 95: 5, and more preferably 70:30 to 90:10, in terms of solid content ratio. preferable.

The aqueous pigment dispersion thus obtained preferably has a volume average particle diameter of 10 to 500 nm. If the volume average particle diameter is larger than 500 nm, it tends to be difficult to obtain a glossy, color-developing and coloring power of the coated object, which is not preferable.
It is very difficult and not realistic to make it smaller than 0 nm.

The aqueous pigment dispersion thus obtained is used by blending it with various aqueous colorant compositions such as aqueous paints, aqueous inks and printing agents.

[0112]

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to the scope of these examples. In the following examples,
"Parts" and "%" are "parts by weight" unless otherwise specified.
And "% by weight" respectively.

The molecular weight in the present invention is GPC.
It is measured by (gel permission chromatography), and the volume average particle diameter is "UPA-15".
“0” (Laser Doppler type particle size distribution meter manufactured by JGC Corporation)
It was measured by.

(Synthesis Example 1) [Synthesis of a vinyl-based copolymer having a carboxyl group and a hydroxyl group] A three-liter four-necked flask equipped with a dropping device, a thermometer, a nitrogen gas introducing pipe, a stirring device and a reflux cooling pipe. Then, 1,000 parts of methyl ethyl ketone was charged and heated to 78 ° C., and then 100 parts of styrene, 538 parts of n-butyl methacrylate, 104 parts of n-butyl acrylate, 150 parts of 2-hydroxyethyl methacrylate, 1 part of methacrylic acid.
A mixed solution consisting of 08 parts and 80 parts of tertiary butyl peroxy-2-ethylhexanoate (“Perbutyl Oh” manufactured by NOF CORPORATION) was added dropwise over 4 hours,
The reaction was carried out at the same temperature for 8 hours. After completion of the reaction, methyl ethyl ketone was added to adjust the nonvolatile content to 50%, and the acid value in the resin solid content was 70 (hereinafter, the acid value is represented by the value in the resin solid content). Average molecular weight is 6,000
A resin solution A of was obtained.

(Synthesis Example 2) [Synthesis of Vinyl Copolymer Having Carboxyl Group and Hydroxyl Group] In Synthesis Example 1, 100 parts of styrene and 45 parts of n-butyl methacrylate were used as the monomer and the polymerization initiator.
4 parts, n-butyl acrylate 143 parts, 2-hydroxyethyl methacrylate 150 parts, methacrylic acid 153
Resin and a resin having an acid value of 100 and a number average molecular weight of 16,000 as the resin solid content, in the same manner as in Synthesis Example 1 except that 20 parts of tert. Solution B was obtained.

(Synthesis Example 3) [Synthesis of Vinyl Copolymer Having Carboxyl Group and Epoxy Group] In Synthesis Example 1, the monomer and the polymerization initiator used were 100 parts of styrene and 47 parts of n-butyl methacrylate.
6 parts, n-butyl acrylate 116 parts, 2-hydroxyethyl methacrylate 150 parts, glycidyl methacrylate 50 parts, methacrylic acid 108 parts and tert-butyl peroxy-2-ethylhexanoate 80 parts In the same manner as in 1, a resin solution C having an acid value of 70 in resin solid content and a number average molecular weight of 10,500 was obtained.

(Synthesis Example 4) [Carboxyl group and N-
Synthesis of Vinyl Copolymer Having Butoxymethylamide Group] In Synthesis Example 1, instead of 1,000 parts of methyl ethyl ketone, 800 parts of methyl ethyl ketone and 200 parts of isopropyl alcohol were used, and the monomer and the polymerization initiator used were styrene 100 Parts, n-butyl methacrylate 459 parts, n-butyl acrylate 83 parts, 2-hydroxyethyl methacrylate 150 parts, N-butoxymethyl methacrylamide 100 parts, methacrylic acid 108 parts and tertiary butyl peroxy-2-ethylhexanoate. In the same manner as in Synthesis Example 1 except that the amount was changed to 80 parts, the acid value of the resin solid content was 70, and the number average molecular weight was 8,
000 resin solutions D were obtained.

(Synthesis Example 5) [Synthesis of Vinyl Copolymer Having Polymerizable Unsaturated Group] A 3 liter four port equipped with a dropping device, a thermometer, a nitrogen gas introducing pipe, a stirring device and a reflux cooling pipe. In a flask, 190 parts of the resin solution A obtained in Synthesis Example 1, 5 parts of 2-methacryloyloxyethyl isocyanate and "Swanox B"
HT "(polymerization inhibitor manufactured by Seikou Kagaku Kogyo Co., Ltd.) 0.0
5 parts were charged and reacted at 70 ° C. for 3 hours. After the reaction was completed, methyl ethyl ketone was added to give a nonvolatile content of 5
Adjust to 0% so that the acid value in resin solids is 67
Thus, a resin solution E having a number average molecular weight of 7,000 was obtained.

(Synthesis Example 6) [Synthesis of Polyester Resin Having Carboxyl Group and Hydroxyl Group] A 2-liter four-necked flask equipped with a dehydration tube, a thermometer, a nitrogen gas introducing tube, and a stirrer was charged with "Cardura E-
10 "(glycidyl ester of synthetic fatty acid manufactured by Shell Chemical Industry Co., Ltd.), 241 parts of adipic acid, 376 parts of hexahydrophthalic anhydride, 195 parts of neopentyl glycol, 165 parts of trimethylolpropane and dibutyltin dioxide 0.5. After charging up parts, the temperature was raised to 190 ° C. over 5 hours while dehydrating, and then a dehydration condensation reaction was carried out at the same temperature. Sampling is performed to measure the acid value, the reaction is terminated so that the target acid value becomes 60, the temperature is lowered, and methyl ethyl ketone is added to obtain a nonvolatile content of 65%.
A resin solution F having an acid value of 61, a number average molecular weight of 2,200, a weight average molecular weight of 30,000, and a hydroxyl value of 60 per resin solid content was obtained by diluting so as to obtain a resin solution F.

(Synthesis Example 7) [Synthesis of Polyurethane Resin Having Carboxyl Group] A 3-liter four-necked flask equipped with a thermometer, a nitrogen gas introducing tube, a stirrer and a reflux cooling tube was charged with 900 parts of methyl ethyl ketone and dimethylol. 129 parts of propionic acid,
521 parts of "Placcel 212" (polylactone diol manufactured by Daicel Chemical Industries, Ltd.) and 350 parts of isophorone diisocyanate were charged and reacted at 78 ° C for 2 hours, and then 0.1 part of dibutyltin dilaurate was added,
Further, the reaction was carried out at the same temperature for 4 hours. After the reaction was completed, the reaction mixture was cooled to 30 ° C., and then ethylenediamine 5.8
Part and methyl ethyl ketone 106 parts were charged and reacted for 1 hour to obtain a resin solution G having an acid value of 54 and a number average molecular weight of 12,000.

Example 1 (1) Pigment Dispersion Step of Kneading Pigment in Aqueous Medium Resin solution A (12.8 parts, solid content: 6.4 parts) was mixed with dimethylethanolamine (0.71 part). After harmonizing
2.29 parts (methyl etherified melamine resin manufactured by Sanwa Chemical Industry Co., Ltd.) "Nikalac MX-041" (1.6 parts in terms of solid content) were mixed. In this mixed solution,
"Fastogen Super Maroon
Maroon) PSK "(cyanine blue pigment manufactured by Dainippon Ink and Chemicals, Inc.) was added while stirring 50 parts of an aqueous slurry having a pigment content of 16% (8 parts by pigment content).

(2) Acid precipitation step Water (in this specification, all ion-exchanged water is used) is added to the dispersion sample to dilute it twice, while stirring with a disper,
A 1N aqueous hydrochloric acid solution was added until the resin became insoluble and fixed to the pigment. The pH at this time was approximately 3-5.

(3) Filtration and Washing Process The pigment to which the resin is fixed is suction filtered, and then the pH of the washing liquid is adjusted.
Was washed with deionized water until a value of 6 was exceeded to obtain a water-containing cake.

(4) Step of Neutralization and Redispersion in Aqueous Medium Water was added until the water-containing cake became fluid, and while stirring with a disper, dimethylethanolamine 10 was added.
% Aqueous solution was added until the pH of the dispersion reached 8.5-9.5, and stirring was continued for 1 hour. Water was added to the redispersion to adjust the nonvolatile content to 20%.

(5) Crosslinking Step To the redispersion, 0.5% of "Nacure 2500X" (crosslinking catalyst manufactured by Kusumoto Kasei Co., Ltd.) was added to the resin solid content, and crosslinking was carried out at 95 ° C. for 1 hour. The reaction was carried out to obtain an aqueous pigment dispersion (A-1).

Comparative Example 1 16 parts of resin solution A (8 parts by solid content) was neutralized with 0.80 part of dimethylethanolamine to prepare a solution of "Fastgen Super Maroon PSK". Aqueous slurry 50 with 16%
Parts (8 parts in terms of pigment) were added with stirring, and then the solvent was removed. Water was added to this to adjust the nonvolatile content to 20% to obtain an aqueous pigment dispersion (a-1).

(Comparative Example 2) A solution prepared by neutralizing 16 parts of resin solution A (8 parts in terms of solid content) with 0.80 part of dimethylethanolamine was used to prepare a pigment component of "Fastgen Super Maroon PSK". Aqueous slurry 50 with 16%
Parts (8 parts in terms of pigment content) are added with stirring, then water is added to the dispersion sample to dilute it twice, while stirring with a disper,
A 1N aqueous hydrochloric acid solution was added until the resin became insoluble and fixed to the pigment. The pH at this time was approximately 3-5.

Next, the pigment to which the resin is fixed is filtered by suction,
Next, the washing liquid was washed with deionized water until the pH of the washing liquid exceeded 6 to obtain a water-containing cake.

Water was added until the water-containing cake became fluid, and while stirring with a disper, a 10% aqueous solution of dimethylethanolamine was added to the dispersion so that the pH of the dispersion was 8.5 to 9.
After adding until it reached 5, stirring was continued for 1 hour as it was. Water was added to the redispersion to adjust the nonvolatile content to 20% to obtain an aqueous pigment dispersion (a-2).

Comparative Example 3 An aqueous pigment dispersion (in the same manner as in Example 1 except that the dispersion sample obtained in the pigment dispersion step in Example 1 was desolvated and then crosslinked) a-3) was obtained.

Example 2 (1) Pigment Dispersion Step 14.4 parts of resin solution B (7.2 parts by solid content), 8 parts of "Fastgen Super Maroon PSK" powder and 40 parts of methyl ethyl ketone were used as an average diameter. Was charged into a 250 cc glass bottle together with 130 parts of 1.5 mm glass beads and kneaded with a paint shaker for 4 hours.

Next, "CR-5L" (hydrophilic epoxy resin manufactured by Dainippon Ink and Chemicals, Inc.) was added to this kneaded product.
After 0.8 parts and 24 parts of methyl ethyl ketone were added and stirred, the glass beads were removed by filtration.

87.2 parts of this dispersion was added to an aqueous solution of 1.2 parts of dimethylethanolamine and 100 parts of water while stirring with a disper to obtain a dispersion sample.

(2) Acid precipitation step Water was added to the dispersion sample to dilute it twice, and 1N phosphoric acid aqueous solution was added with stirring with a disper until the resin was insolubilized and fixed to the pigment. The pH at this time was 5.

(3) Filtration and Washing Step The pigment to which the resin is fixed is suction filtered, and then the pH of the washing solution is adjusted.
Was washed with deionized water until a value of 6 was exceeded to obtain a water-containing cake.

(4) Step of Neutralization and Redispersion in Aqueous Medium Water was added until the water-containing cake became fluid, and while stirring with a disper, 10 parts of dimethylethanolamine was added.
% Aqueous solution was added until the pH of the dispersion reached 8.5-9.5, and stirring was continued for 1 hour. Water was added to the redispersion to adjust the nonvolatile content to 20%.

(5) Crosslinking Step The redispersion was subjected to a crosslinking reaction at 95 ° C. for 1 hour to obtain an aqueous pigment dispersion (B-1).

(Comparative Example 4) In Example 2, the amount of the resin solution B used was 16 parts, and no epoxy resin was used.
Aqueous pigment dispersion (b-) was prepared in the same manner as in Example 2 except that a 1 N hydrochloric acid aqueous solution was used instead of the normal phosphoric acid aqueous solution.
1) was obtained.

(Comparative Example 5) An aqueous pigment dispersion (Comparative Example 5) was prepared in the same manner as in Example 2 except that the dispersion sample obtained in the pigment dispersion step was desolvated and then crosslinked. b-2) was obtained.

Example 3 In Example 1, the melamine resin was not used, and instead of the resin solution A, the resin solution C16 was used.
Parts (8 parts in solid content), the amount of diethylethanolamine used was 0.80 parts, and 1N phosphoric acid aqueous solution was used in place of 1N hydrochloric acid aqueous solution, and acid precipitation was performed until pH 5 was reached. A self-crosslinking aqueous pigment dispersion (C-1) was obtained in the same manner as in Example 1 except that the crosslinking reaction was carried out at 95 ° C for 1 hour without using "Nacure 2500X".

Example 4 In Example 1, the melamine resin was not used, and instead of the resin solution A, the resin solution D16 was used.
Parts (8 parts by solid content) were used, and a self-crosslinking aqueous pigment dispersion (D-1) was obtained in the same manner as in Example 1 except that the crosslinking reaction was carried out at 120 ° C. for 1 hour.

Example 5 In Example 1, the melamine resin was not used, and instead of the resin solution A, the resin solution E16 was used.
Part (8 parts in solid content) is used, and "Nacure 2500
X ”in place of ammonia persulfate 0.5% with respect to the resin solid content, and the cross-linking reaction was carried out at 90 ° C. for 3 hours, and the self-crosslinking aqueous pigment dispersion was carried out in the same manner as in Example 1. The body (E-1) was obtained.

Example 6 (1) Pigment Dispersion Step Resin solution F 12.8 parts (solids 6.4 parts), "Fastogen Blue FGF" (manufactured by Dainippon Ink and Chemicals, Inc.) Of copper phthalocyanine pigment) and 40 parts of methyl ethyl ketone having an average diameter of 1.
A 250 cc glass bottle was charged with 130 parts of 5 mm glass beads and kneaded for 4 hours with a paint shaker.

Next, this kneaded product was mixed with "Nikalac MX
-041 "2.29 parts (1.6 parts in terms of solid content)," Nacure 2500X "0.04 part and methyl ethyl ketone 24 parts were added and stirred, and then the glass beads were removed by filtration.

87.1 of this dispersion in an aqueous solution consisting of 0.65 parts of dimethylethanolamine and 100 parts of water.
3 parts was added while stirring with a disper, and then the solvent was removed under reduced pressure to obtain a dispersion sample.

(2) Acid precipitation step-Crosslinking step Using this dispersion sample, "Nacure 250
0X ”was used, and the crosslinking reaction was carried out at 95 ° C. for 1 hour, in the same manner as in Example 1 except that the acid precipitation step, the filtration and washing steps, the neutralization and redispersion in an aqueous medium step, and the crosslinking step were carried out. The steps were performed to obtain an aqueous pigment dispersion (F-1).

Example 7 Using the dispersion sample obtained in the pigment dispersion step of Example 6, a crosslinking reaction was carried out at 95 ° C. for 2 hours, and then, similarly to Example 1, an acid precipitation step and a filtration step were sequentially performed. Then, a water washing step, a neutralization step and a redispersion step in an aqueous medium were carried out to obtain an aqueous pigment dispersion (F-2).

Comparative Example 6 (1) Pigment Dispersion Step 16 parts of resin solution F (8 parts by solid content), “Fastgen
8 parts of "Fastogen Blue FGF" powder and 40 parts of methyl ethyl ketone were charged into a 250 cc glass bottle together with 130 parts of glass beads having an average diameter of 1.5 mm, and were kneaded for 4 hours with a paint shaker.

Next, to this kneaded product, 24 parts of methyl ethyl ketone was added and stirred, and then glass beads were removed by filtration.

88 parts of this dispersion was added to an aqueous solution consisting of 0.8 part of dimethylethanolamine and 100 parts of water.
The mixture was charged with a disper with stirring, and then the solvent was removed under reduced pressure to obtain a dispersion sample.

(2) Acid precipitation step-neutralization and redispersion step in an aqueous medium Using this dispersed sample, except that the crosslinking step was not carried out,
In the same manner as in Example 1, an acid precipitation step, a filtration step, a water washing step, a neutralization step and a redispersion step in an aqueous medium were sequentially performed to obtain an aqueous pigment dispersion (f-1).

(Comparative Example 7) An aqueous pigment dispersion (f-2) was obtained in the same manner as in Example 6 except that the acid precipitation step was not carried out.

Example 8 (1) Pigment Dispersion Step After 7.2 parts of resin solution G (3.6 parts by solid content) was neutralized with 0.31 part of dimethylethanolamine, "CR-5" was prepared.
L "0.4 part was mixed, and 43.1 parts of water was added dropwise with stirring to obtain an aqueous dispersion.

To this aqueous dispersion was added "Shimla Fast.
Red (Symuler Fast Red) 4195 "(insoluble azo pigment manufactured by Dainippon Ink and Chemicals, Inc.) and 130 parts of glass beads are added, and the mixture is kneaded for 4 hours with a paint shaker, then dispersed by removing the glass beads by filtration. A sample was obtained.

(2) Acid precipitation step Water was added to the dispersion sample to double the dilution, and 1N phosphoric acid aqueous solution was added with stirring with a disper until the resin was insolubilized and fixed to the pigment. The pH at this time was 5.

(3) Filtration and Washing Process The pigment to which the resin is fixed is suction filtered, and then the pH of the washing liquid is adjusted.
Was washed with deionized water until a value of 6 was exceeded to obtain a water-containing cake.

(4) Neutralization and Redispersion in Aqueous Medium Water was added until the water-containing cake became fluid, and while stirring with a disper, 10% ammonia water was added to adjust the pH of the dispersion to 8.5. After adding until 9.5, 1 as it is
Stirring was continued for hours. Water was added to the redispersion to adjust the nonvolatile content to 20%.

(5) Crosslinking Step The redispersion was subjected to a crosslinking reaction at 95 ° C. for 1 hour to give an aqueous pigment dispersion (G-1) having a dispersion resin / pigment ratio of 1/2 in terms of solid content. ) Got.

(Comparative Example 8) In Example 8, "CR-
5 L ”was used to knead the pigment using 8 parts of resin solution G (4 parts in terms of solid content), followed by acid precipitation, filtration and washing with water, neutralization with aqueous ammonia, and dispersion in water. Thus, a non-crosslinked aqueous pigment dispersion (g-1) having a dispersion resin / pigment ratio of 1/2 in terms of solid content was obtained.

(Comparative Example 9) In Example 8, the resin solution G was neutralized with aqueous ammonia, desolvation was carried out without acid precipitation, and then crosslinking was carried out to obtain a solid dispersion resin / pigment ratio. An aqueous pigment dispersion (g-2) having a ratio of 1/2 was obtained.

The constitutions of various aqueous pigment dispersions thus obtained are summarized in Table 1 below.

[0162]

[Table 1]

In the above table, PSK stands for "Fastgen Super Maroon PSK", FGF stands for "Fastgen Blue FGF", and 4195 stands for "Shimla Fast Red 4195".

(Example 9) "Watersol S-751" (manufactured by Dainippon Ink and Chemicals, Inc., water-soluble acrylic resin for non-volatile components for baking paint with 50% non-volatile content) 56 parts (28 parts in solid content) "Cymel 303 "(Methyl ether melamine resin with 98% active ingredient manufactured by Mitsui Cyanamid Co., Ltd.) 12.25 parts (12 parts by solid content) Ratio of 100 parts (20 parts by solid content) of aqueous pigment dispersion (A-1) So that the nonvolatile content is 24
A water-soluble baked acrylic resin paint was prepared by diluting it so that the amount thereof became%.

This paint was applied to "BT-144 treated steel plate"
(Zinc phosphate-treated steel sheet manufactured by Nippon Parker Rising Co., Ltd.) was coated with a bar coater so that the film thickness was 20 ± 2 μm, set for 10 minutes, and then baked at 150 ° C. for 20 minutes to give a test piece. Was produced.

[0166] Further, this paint was treated with corona discharge treated PET.
The film is coated with a bar coater so that the film thickness is 10 ± 1 μm, and after setting for 10 minutes, 150 ° C
Then, baking was performed for 20 minutes to prepare a test piece.

(Comparative Examples 10 to 12) In Example 9,
A water-soluble pigment was prepared in the same manner as in Example 9 except that the aqueous pigment dispersion (a-1), (a-2) or (a-3) was used instead of the aqueous pigment dispersion (A-1). A fire resistant acrylic resin paint was prepared and a test piece was prepared.

(Example 10) In Example 9, instead of the aqueous pigment dispersion (A-1), an aqueous pigment dispersion (B-
A water-soluble baked acrylic resin paint was prepared in the same manner as in Example 9 except that 1) was used to prepare test pieces.

(Comparative Examples 13 and 14) In Example 9, except that the aqueous pigment dispersion (b-1) or (b-2) was used instead of the aqueous pigment dispersion (A-1), respectively. In the same manner as in Example 9, a water-soluble baked acrylic resin paint was prepared and test pieces were prepared.

(Examples 11 to 13) In Example 9,
A water-soluble pigment was prepared in the same manner as in Example 9 except that the aqueous pigment dispersion (C-1), (D-1) or (E-1) was used instead of the aqueous pigment dispersion (A-1). A fire resistant acrylic resin paint was prepared and a test piece was prepared.

(Examples 14 and 15) In Example 9, instead of "Waterzor S-751", "Waterzol S-212" (manufactured by Dainippon Ink and Chemicals, Inc., a non-volatile content of 65% baking paint) Water-soluble polyester resin) for 43 parts (28 parts in solid content) is used,
A water-soluble polyester resin baking coating was prepared in the same manner as in Example 9 except that the aqueous pigment dispersion (F-1) or (F-2) was used instead of the aqueous pigment dispersion (A-1). Then, a test piece was prepared.

(Comparative Examples 15 and 16) In Example 14, except that the aqueous pigment dispersion (f-1) or (f-2) was used instead of the aqueous pigment dispersion (F-1), respectively. A water-soluble polyester resin baking paint was prepared in the same manner as in Example 14 to prepare a test piece.

(Example 16) "HYDRAN AP-40" and the aqueous pigment dispersion were weighed in terms of solid content to give "HYDRAN AP-40" (non-volatile content 2 manufactured by Dainippon Ink and Chemicals, Inc. 2 2. 5% water-soluble polyurethane resin) 178 parts (40 parts by solid content) Aqueous pigment dispersion (G-1) 300 parts (60 parts by solid content) were mixed, and 10 parts of ethanol was added to the non-volatile A 20% water based ink was prepared.

This ink was applied to a corona discharge treated PET film with No. After painting with 7 bar coater,
A sample was prepared by drying at 60 ° C. for 1 minute.

(Comparative Examples 17 and 18) In Example 16, except that the aqueous pigment dispersion (g-1) or (g-2) was used instead of the aqueous pigment dispersion (G-1), respectively. An aqueous ink was prepared in the same manner as in Example 16,
A sample was prepared.

(Example 17) First, a printing paste was prepared as follows. "Ryudai W Reducer Conc 500" 50 parts (thickener manufactured by Dainippon Ink and Chemicals, Inc.) Mineral terpen 650 parts Water 300 parts were weighed in a beaker and stirred for 30 minutes with a homomixer.

Next, a printing agent was prepared by blending as follows. Aqueous pigment dispersion (A-1) 1.0 part (pigment content 0.1 part) Water 1.0 part The above printing paste 16.0 parts "Ryudai W Fixer 756K-1" 2.0 parts (Dainippon Ink and Chemicals) Acrylic resin emulsion manufactured by Kogyo Co., Ltd.) was weighed in a beaker and stirred for 30 minutes with a homomixer to prepare a printing agent.

A printing agent as a standard product was prepared as follows. Preparation of color base "Fastogen Super Maroon PSK" 15.0 parts "Emulgen 911" (surfactant manufactured by Kao Corporation) 7.2 parts Water 77.8 parts together with 130 g of glass beads having an average diameter of 1.5 mm,
A 250 cc glass bottle was weighed and kneaded for 4 hours with a paint shaker to prepare a color base.

Next, the above color base 0.67 parts (pigment content 0.1 part) water 1.33 parts printing paste 16.00 parts "Ryudai W Fixer 756K-1" 2.00 parts were weighed into a beaker and homogenized. A standard printing agent was prepared by stirring for 30 minutes with a mixer.

The printing agent thus prepared was color-developed with a doctor on cotton satin using a 90 mesh screen and dried at 120 ° C. for 5 minutes to give a test cloth.

(Comparative Examples 19 to 21) In Example 17, the aqueous pigment dispersion (a-1), (a-2) or (a-3) was used in place of the aqueous pigment dispersion (A-1). A printing agent was prepared and a test cloth was prepared in the same manner as in Example 17 except that each was used.

(Example 18) In Example 17, instead of the aqueous pigment dispersion (A-1), an aqueous pigment dispersion (B-
A printing agent was prepared and a test cloth was prepared in the same manner as in Example 17 except that 1) was used.

(Comparative Examples 22 and 23) In Example 17, except that the aqueous pigment dispersion (b-1) or (b-2) was used instead of the aqueous pigment dispersion (A-1), respectively. A printing agent was prepared and a test cloth was prepared in the same manner as in Example 17.

<Evaluation> (1) Volume average particle size The volume average particle size immediately after the preparation of the aqueous pigment dispersions obtained in each Example and each Comparative Example and after standing at room temperature for 30 days was
It measured using "UPA-150" (laser Doppler type particle size distribution analyzer made by JGC Corporation). The results are summarized in Table 2.

[0185]

[Table 2]

From the results shown in Table 2, the aqueous pigment dispersion obtained by the production method of the present invention has almost constant particle size immediately after production and after 30 days from the production, and therefore exhibits stable dispersion. Understand that it is excellent. On the other hand, since the aqueous pigment dispersions obtained in Comparative Examples 1, 3, 5, 7 and 9 were not subjected to acid precipitation, the dispersion stability was not good, and the aqueous pigment dispersions obtained in Comparative Examples 2, 6 and 8 were obtained. The pigment dispersion is excellent in dispersion stability because it is subjected to acid precipitation, but it is inferior in water resistance of the coating film as described later because it is not crosslinked by using a crosslinking agent.

(2) Evaluation in Baking Paint The paints obtained in Examples 9 to 15 and Comparative Examples 10 to 16 were evaluated as follows. The results of the water-soluble acrylic resin baking paint are shown in Table 3, and the results of the water-soluble polyester resin baking paint are shown in Table 4.

Gloss: The product coated on "BT-144 treated steel plate" was measured with 60 ° specular gloss.

Coloring property: The PET film coated was visually evaluated. Evaluation Criteria ⊚: High color density and high hiding power.

A: Color density and hiding property are slightly inferior. Δ: The color density and hiding property are considerably poor. X: The color density and hiding property are considerably poor, and the sharpness is also low.

Water resistance: The coated "BT-144 treated steel plate" was immersed in water at a temperature of 50 ° C., and after 96 hours, the degree of blister generation was visually determined. Evaluation criteria ◎: No abnormality.

B: Slight blistering was observed. B: Significant blister formation was observed. X: Blister occurred on the entire surface of the test piece.

[0193]

[Table 3]

[0194]

[Table 4]

From the results shown in Tables 3 and 4, the paint using the aqueous pigment dispersion obtained by the production method of the present invention has a gloss,
It can be seen that the color development and the water resistance are excellent.

(3) Evaluation in water-based ink The water-based inks obtained in Example 16 and Comparative Examples 17 to 18 were evaluated as follows. The results are summarized in Table 5.

-Gloss: 60 ° specular gloss-Coloring property: Same evaluation as in the case of baking paint-Water resistance: Using a rubbing tester tester manufactured by Ohira Rika Kogyo Co., Ltd., applying a load of 0.1 kg to apply water. The impregnated felt was rubbed 10 times.

Evaluation Criteria A: The felt is not colored at all. ◯: The felt was slightly colored.

Δ: The felt was considerably colored, and the ink was partly peeled from the test piece. X: The felt was markedly colored, and the ink was peeled off from the test piece.

[0200]

[Table 5]

From the results shown in Table 5, it can be understood that the aqueous ink using the aqueous pigment dispersion obtained by the production method of the present invention is excellent in gloss and startability.

(4) Evaluation of Printing Agents The printing agents obtained in Examples 17 to 18 and Comparative Examples 19 to 23 were evaluated as follows. The results are summarized in Table 6.・ Coloring power: The coloring power was measured with a spectrophotometer, and the coloring power of the test cloth coated with the standard printing agent dispersed with an emulsifier was 100%.
The coloring powers of Examples and Comparative Examples are expressed as%. Water resistance: Using a rubbing tester tester manufactured by Ohira Rika Kogyo Co., Ltd., rubbing was performed 50 times with a felt impregnated with water under a load of 1 kg.

Evaluation Criteria ⊚: The felt has no color at all. ◯: The felt was slightly colored.

Δ: The felt was considerably colored and discoloration of the test piece was recognized. X: The felt was markedly colored, and the test piece was considerably discolored.

[0205]

[Table 6]

From the results shown in Table 6, it can be understood that the printing agent using the aqueous pigment dispersion obtained by the production method of the present invention is excellent in coloring power and water resistance.

[0207]

The aqueous pigment dispersion obtained according to the production method of the present invention is excellent in storage stability due to acid precipitation, and when used in aqueous paints, aqueous inks and printing agents, gloss and color developability. It also has excellent coloring power, and when it is crosslinked, it has excellent water resistance, which is extremely practical.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display area C09D 175/04 PHN C09D 175/04 PHN 201/06 PDF 201/06 PDF

Claims (15)

[Claims] 1. A resin (B) comprising a pigment (A) and a resin (B) having a carboxyl group and a crosslinkable functional group.
Aqueous dispersion (1a) of a pigment, which is made hydrophilic by neutralizing the carboxyl group of the above with a basic compound (F1)
(1) in which the resin (B) is deposited and fixed to the pigment by making the pH neutral or acidic using the acidic compound (E), and then the carboxyl group of the resin (B) is added to the basic compound. By neutralizing with (F2),
A method for producing an aqueous pigment dispersion, comprising the step (2) of redispersing a pigment to which a resin (B) has been fixed in an aqueous medium, and incorporating a crosslinking agent (C) at an arbitrary time, and
An aqueous pigment dispersion characterized by reacting a crosslinkable functional group of a resin (B) with a crosslinking agent (C) to crosslink at any time after obtaining an aqueous dispersion (1a) of a pigment. Production method. 2. A pigment (A) and a resin (B) are kneaded in an organic solvent medium as an aqueous pigment dispersion (1a), and a cross-linking agent (C) is added before or after the kneading. Furthermore, before and / or after kneading, the resin (B)
At least a part of the carboxyl group of the basic compound (F
The production method according to claim 1, wherein an aqueous dispersion of the pigment obtained by dispersing in an aqueous medium by neutralizing with 1) is used. 3. An aqueous pigment dispersion (1a) comprising a pigment (A), a resin (B) having a carboxyl group neutralized with a basic compound (F1), and a crosslinking agent (C). The production method according to claim 1, wherein an aqueous dispersion of a pigment obtained by mixing and / or kneading in a medium is used. 4. The resin (B) is a vinyl-based copolymer, a polyester resin or a polyurethane resin,
4. The production method according to 2 or 3. 5. The production method according to claim 1, wherein the acid value based on the carboxyl group of the resin (B) is in the range of 30 to 120 KOHmg / 1 g of resin solid content. 6. A cross-linking agent selected from the group consisting of a carboxyl group as the cross-linkable functional group of the resin (B) and an amino resin and a compound having two or more epoxy groups in the molecule as the cross-linking agent (C). Alternatively, the production method according to claim 1, 2, 3, 4, or 5, wherein the crosslinkable functional group of the resin (B) is a hydroxyl group, and the crosslinking agent (C) is an amino resin. 7. Crosslinking with a crosslinkable functional group of the resin (B) before adding the acidic compound (E) or after redispersing the pigment (A) to which the resin (B) is fixed in an aqueous medium. The method according to any one of claims 1 to 6, wherein the agent (C) is reacted and crosslinked. 8. A pigment (A) and a resin (D) having a carboxyl group and a self-crosslinking functional group are used, and the carboxyl group of the resin (D) is neutralized with a basic compound (F1). Aqueous dispersion of pigment (1
b) step (1) of precipitating the resin (D) by fixing the pH to neutral or acidic with the acidic compound (E) and fixing the resin (D) to the pigment, and then the carboxyl group of the resin (D) is basic. A method for producing an aqueous pigment dispersion, comprising a step (2) of redispersing a pigment (A) to which a resin (D) is fixed in an aqueous medium by neutralizing with a compound (F2), and A method for producing an aqueous pigment dispersion, which comprises self-crosslinking the resin (D) at any time after obtaining the aqueous pigment dispersion (1b). 9. An aqueous dispersion (1b) of a pigment, wherein the pigment (A) and the resin (D) are kneaded in an organic solvent medium, and the carboxyl group of the resin (D) is mixed before and / or after the kneading. 9. The production method according to claim 8, wherein the pigment aqueous dispersion (1b) is obtained by dispersing at least a part of the pigment in an aqueous medium by neutralizing the pigment with a basic compound (F1). 10. A pigment (A) and a basic compound (F1)
9. The production method according to claim 8, wherein the pigment aqueous dispersion (1b) obtained by mixing and / or kneading the resin (D) whose carboxyl group is neutralized with the above in an aqueous medium is used. 11. The production method according to claim 8, wherein the resin (D) is a vinyl-based copolymer, a polyester resin or a polyurethane resin. 12. The method according to claim 8, wherein the acid value based on the carboxyl group of the resin (D) is in the range of 30 to 120 KOHmg / 1 g of resin solid content. 13. The self-crosslinking functional group of the resin (D) is
(1) one having a carboxyl group and an epoxy group in one molecule, (2) one having a hydroxyl group and an N-alkoxymethylamide group in one molecule, or (3) a radically polymerizable unsaturated group. , 9, 10, 11 or 12, the manufacturing method. 14. The resin (D) is self-crosslinked before the addition of the acidic compound (E) or after redispersing the pigment (A) to which the resin (D) is fixed in an aqueous medium. ~
13. The manufacturing method according to any one of 13. 15. An aqueous colorant composition comprising the aqueous pigment dispersion produced by the production method according to any one of claims 1 to 14.