JP7077558B2 - Aqueous polyurethane resin dispersion and its use - Google Patents

Description

The present invention relates to an aqueous polyurethane resin dispersion in which a polyurethane resin is dispersed in an aqueous medium, and more particularly to an aqueous polyurethane resin that gives a coating film having high adhesion to a substrate. The present invention also comprises a method for producing the aqueous polyurethane resin dispersion, a coating composition containing the aqueous polyurethane resin dispersion, a coating composition, an ink composition, and the polyurethane resin dispersion. The present invention relates to a polyurethane resin film obtained by drying an object.

Since the aqueous polyurethane resin dispersion is an environment-friendly material capable of reducing volatile organic compounds as compared with the conventional solvent-based urethane, it is a material that is being replaced with solvent-based polyurethane.
Since the water-based polyurethane resin dispersion has excellent adhesion to the substrate, abrasion resistance, impact resistance, solvent resistance, etc., it can be used as a paint, ink, adhesive, various coating agents, such as paper and plastics. Widely used in films, metals, rubbers, elastomers, textile products, etc.
In recent years, there has been an increasing demand for surface protective coating agents such as plastic substrates and metal substrates, and in particular, water-based polyurethane resins having high adhesion to metal substrates are desired.
For example, a composite resin composition characterized by containing a composite resin in which a polyurethane having an alkyl group having 2 to 20 carbon atoms in a side chain and a vinyl polymer are bonded via a polysiloxane structure is disclosed. (See, for example, Patent Document 1).

JP 2011-105906

However, in the resin composition described in Patent Document 1, it is necessary to use a compound having a hydrolyzable silyl group or a silanol group separately from the polyurethane resin in order to form a siloxane structure for adjusting the mechanical properties. rice field. In a polyurethane resin composition that does not introduce a third component such as a siloxane structure, the adhesion of the coating agent to the base material is insufficient, and the plastic base material or the metal base material can be used without the presence of the third component. A polyurethane resin dispersion applicable as a coating agent for surface protection has not been known.

The present invention has been made to solve the above problems, and has a structure derived from a polycarbonate polyol having an alicyclic structure, a structure derived from a polyisocyanate, a structure derived from an acidic group-containing polyol, and a chain extender. It has been found that the above-mentioned problems can be solved by the aqueous polyurethane resin dispersion having the partial structures represented by the following formulas (1) and (2) in the aqueous polyurethane resin dispersion having the derived structure.

INDUSTRIAL APPLICABILITY The present invention provides an aqueous polyurethane resin dispersion having high adhesion to a substrate.

Hereinafter, embodiments of the present invention will be described in detail. In a polymer compound like the present invention, a product having a large number of structures can be obtained by reacting a plurality of types of raw material compounds. Therefore, even if a large number of included structures can be described by a general formula, the polymer compound is not uniquely shown by the structure. In addition, it is difficult to directly measure and identify the physical characteristics by instrumental analysis or the like, or to distinguish them from existing compounds. Therefore, in the present invention, a polymer compound such as "aqueous polyurethane resin dispersion" may be specified by a production method as necessary.

The aqueous polyurethane resin dispersion of the present invention has a structure derived from a polycarbonate polyol having an alicyclic structure, a structure derived from a polyisocyanate, a structure derived from an acidic group-containing polyol, and a structure derived from a chain extender. It is an aqueous polyurethane resin dispersion having a partial structure represented by the following formulas (1) and (2) in the resin dispersion.

(Structure derived from polycarbonate polyol having an alicyclic structure)
The structure derived from the polycarbonate polyol having an alicyclic structure indicates a partial structure of the molecular structure of the polycarbonate polyol having an alicyclic structure other than the groups involved in the urethanization reaction. The structure of the polyurethane resin may contain a group derived from a polycarbonate polyo having a plurality of alicyclic structures.

Examples of the polycarbonate polyol that introduces a structure derived from a polycarbonate polyol having an alicyclic structure into polyurethane include a polycarbonate polyol having a structure derived from a polyol having an alicyclic structure having 5 to 12 carbon atoms.
The structure derived from a polyol having an alicyclic structure having 5 to 12 carbon atoms is a group of polyol molecules having an alicyclic structure having 5 to 12 carbon atoms other than the groups involved in the carbonateization reaction. Indicates a partial structure.
Specific examples of the polyol for introducing a structure derived from a polyol having an alicyclic structure having 5 to 12 carbon atoms into a polycarbonate polyol include 1,4-cyclohexanedimethanol and 1,3-cyclohexanedimethanol. 1,4-Cyclohexanediol, 1,3-Cyclopentanediol, 1,4-Cycloheptandiol, 2,5-bis (hydroxymethyl) -1,4-dioxane, 2,7-norbornandiol, tetrahydrofurandimethanol , 1,4-Bis (hydroxyethoxy) cyclohexane and the like, but are not limited thereto.

Further, the polycarbonate polyol having an alicyclic structure may have a structure derived from a polyol having no alicyclic structure as a part of the structure.
Examples of the polyol for introducing a structure derived from a polyol having no alicyclic structure into a polycarbonate polyol include an aliphatic polyol, and for example, an aliphatic polyol having 2 to 12 carbon atoms. Specifically, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9 -Linear aliphatic diols such as nonanediol; 2-methyl-1,3-propanediol, 2-methyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 2-methyl-1 , 9-Nonandiol and other branched chain aliphatic diols; trifunctional or higher polyhydric alcohols such as trimethylolpropane and pentaerythritol can be mentioned, but are not limited thereto.

For a polycarbonate polyol having a structure derived from a polyol having no alicyclic structure in the molecule, a polycarbonate polyol shall be prepared by a usual method using a polyol having an alicyclic structure and a polyol other than the polyol. And you can get it. The proportion of the structure derived from the polyol having the alicyclic structure in the polycarbonate polyol having the alicyclic structure can be appropriately adjusted by the ratio of the polyol added at the time of preparing the polycarbonate polyol, but has the alicyclic structure. The proportion of the structure derived from the polyol is preferably 10 mol% or more, more preferably 20 mol% or more, and particularly preferably 25 mol% or more.
Within this range, an aqueous polyurethane resin dispersion having high adhesion to the substrate can be obtained.

(Structure derived from polyisocyanate)
In the present invention, the polyisocyanate-derived structure refers to a partial structure of the molecular structure of polyisocyanate other than the groups involved in the polyurethane-forming reaction.
In the aqueous polyurethane resin dispersion of the present invention, the polyisocyanate-derived structure preferably includes a structure derived from an aliphatic polyisocyanate and a structure derived from an aromatic polyisocyanate.
Further, the structure derived from the aliphatic polyisocyanate indicates a partial structure of the molecular structure of the polyisocyanate other than the group involved in the polyurethaneization reaction, and the structure derived from the aromatic polyisocyanate is the aromatic polyisocyanate. Of the molecular structures of the above, the partial structures other than the groups involved in the polyurethaneization reaction are shown.

(Aliphatic polyisocyanate)
Examples of the polyisocyanate that introduces the structure derived from the aliphatic polyisocyanate into polyurethane include aliphatic polyisocyanates having two or more isocyanato groups, specifically, ethylene diisocyanate, tetramethylene diisocyanate, and hexamethylene diisocyanate (HDI). ), Dodecamethylene diisocyanate, 1,6,11-undecantryisocyanate, 2,2,4-trimethylhexamethylenediisocyanate, lysine diisocyanate, 2,6-diisocyanatomethylcaproate, bis (2-isocyanatoethyl) fumarate , Bis (2-isocyanatoethyl) carbonate, 2-isocyanatoethyl-2,6-diisocyanatohexanoate and other aliphatic polyisocyanates and isophorone diisocyanates (IPDI), 4,4'-dicyclohexylmethanediisocyanate (hydrogen) Addition MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TDI), bis (2-isocyanatoethyl) -4-diclohexene-1,2-dicarboxylate, 2,5-norbornandiisocyanate, 2,6- Examples thereof include, but are not limited to, aliphatic polycyanates having an alicyclic structure such as norbornandiisocyanate.

(Aromatic polyisocyanate)
Examples of the polyisocyanate that introduces the structure derived from the aromatic polyisocyanate into polyurethane include aromatic polyisocyanates having two or more isocyanato groups, specifically 1,3-phenylenediisocyanate and 1,4-phenylene. Diisocyanate, 2,4-tolylene diisocyanate (TDI), 2,6-tolylene diisocyanate, 4,4'-diphenylenemethane diisocyanate (MDI), 2,4-diphenylmethane diisocyanate, 4,4'-diisocyanetobiphenyl , 3,3'-dimethyl-4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatodiphenylmethane, 1,5-naphthylene diisocyanate, m-isocyanatophenylsulfonyl isocyanate , P-isocyanatophenylsulfonyl isocyanate and the like, but are not limited thereto.

The structure derived from the polyisocyanate preferably includes the structure derived from the aliphatic isocyanate having the alicyclic structure and the structure derived from the aromatic isocyanate.
Further, the amount of the structure derived from the aliphatic isocyanate having the alicyclic structure and the structure derived from the aromatic isocyanate can be designed at an arbitrary ratio depending on the amount of isocyanate added at the time of preparing the polyurethane, but it is preferable. The molar ratio of the structure derived from the aliphatic isocyanate having an alicyclic structure to the structure derived from the aromatic isocyanate is 80:20 to 20:80, more preferably 80:20 to 50:50, and particularly preferably 80: It is 20 to 60:40.
Within this range, an aqueous polyurethane resin dispersion having higher adhesion to the substrate can be obtained.

(Structure derived from acidic group polyol)
In the present invention, the structure derived from the acidic group-containing polyol means a partial structure of the molecular structure of the acidic group-containing polyol other than the groups involved in the polyurethane-forming reaction.
Examples of the polyol that introduces a structure derived from an acidic group-containing polyol into polyurethane include a polyol having at least one acidic group in the molecule. The acidic group is not particularly limited, and examples thereof include a carboxy group, a sulfonyl group, a phosphoric acid group, and a phenolic hydroxyl group.
The type of the acid group-containing polyol is not particularly limited, but specifically, dimethylol alkanoic acid such as 2,2-dimethylol propionic acid and 2,2-dimethylol butanoic acid, and N, N-bishydroxyethylglycine. , N, N-bishydroxyethylalanine, 3,4-dihydroxybutanesulfonic acid, 3,6-dihydroxy-2-toluenesulfonic acid and the like. Among these, from the viewpoint of availability, an alkanoic acid having 4 to 12 carbon atoms (dimethylol alkanoic acid) containing two methylol groups is preferable, and among them, 2,2-dimethylol propionic acid is preferable.
In the polyurethane resin of the present invention, the structure derived from the acidic group-containing polyol may have a structure derived from a plurality of types of acidic group-containing polyols by using a plurality of types of acidic group-containing polyols.

前記式（１）は、イソシアナト基とアミノ基との反応により生じる部分構造（下記の反応式（Ａ））であり、前記式（２）は、イソシアナト基とイミノ基との反応により生じる部分構造（下記の反応式（Ｂ））である。
式（１）は、例えば、イソシアナト基と（ａ）２以上のアミノ基のみを有する鎖延長剤のアミノ基との反応により生じる部分構造、またはイソシアナト基と（ｃ）アミノ基及びイミノ基を少なくとも１つずつ有する鎖延長剤のアミノ基との反応により生じる部分構造である。
また、式（２）は、例えば、イソシアナト基と（ｂ）２以上のイミノ基のみを有する鎖延長剤のイミノ基との反応により生じる部分構造、またはイソシアナト基と（ｃ）アミノ基及びイミノ基を少なくとも１つずつ有する鎖延長剤のイミノ基との反応により生じる部分構造である。

(Partial structure)
The aqueous polyurethane resin dispersion of the present invention has the following partial structures of the formulas (1) and (2).

The formula (1) is a partial structure (reaction formula (A) below) generated by a reaction between an isocyanato group and an amino group, and the formula (2) is a partial structure generated by a reaction between an isocyanato group and an imino group. (The following reaction formula (B)).
The formula (1) is, for example, a partial structure generated by the reaction of an isocyanato group with an amino group of (a) a chain extender having only two or more amino groups, or at least an isocyanato group and (c) an amino group and an imino group. It is a partial structure generated by the reaction with the amino group of the chain extender having one by one.
Further, the formula (2) is, for example, a partial structure generated by a reaction between an isocyanato group and (b) an imino group of a chain extender having only two or more imino groups, or an isocyanato group and (c) amino group and imino group. It is a partial structure generated by the reaction with the imino group of the chain extender having at least one of.

The molar ratio of the formula (1) and the formula (2) can be designed at any ratio by adjusting the ratio of the amino group and the imino group that react with the isocyanato group.
Furthermore, the ratio of the amino group and the imino group that react with the isocyanato group can be designed at any ratio by adjusting the type and amount of the chain extender.
The molar ratio of the formula (1) to the formula (2) is preferably 99: 1 to 1:99, more preferably 95: 5 to 5:95, still more preferably 90:10 to 10:90. Particularly preferably, it is 80:20 to 20:80.
Within this range, an aqueous polyurethane resin dispersion having higher adhesion to the substrate can be obtained.
(Structure derived from chain extender)
In the present invention, the structure derived from the chain extender refers to a partial structure of the molecular structure of the chain extender other than the groups involved in the chain extension reaction.
In the aqueous polyurethane resin dispersion of the present invention, the structure derived from the chain extender is a structure derived from a chain extender having only two or more amino groups, a structure derived from a chain extender having only two or more imino groups, and an amino group. And it is preferable to have two or more structures selected from the group consisting of a structure derived from a chain extender having at least one imino group.
Further, the structure derived from the chain extender having only two or more amino groups indicates a partial structure of the molecular structure of the chain extender other than the group involved in the chain extension reaction, and two or more imino groups. The structure derived from the chain extender having only one indicates a partial structure of the molecular structure of the chain extender other than the group involved in the chain extension reaction, and has at least one amino group and one imino group. The structure derived from the extender indicates a partial structure of the molecular structure of the chain extender other than the group involved in the chain extension reaction.

((A) Chain extender having only 2 or more amino groups)
Examples of the compound that introduces a structure derived from a chain extender having only two or more amino groups into polyurethane include compounds having only two or more amino groups, specifically, ethylenediamine, isophoronediamine, and 2-methyl-. 1,5-Pentanediamine, 1,2-bis (2-amino-2-propyl) benzene, 1,3-bis (2-amino-2-propyl) benzene, 1,4-bis (2-amino-2) -Propyl) benzene and the like, but are not limited to these.

((B) Chain extender having only 2 or more imino groups)
Examples of the compound for introducing a structure derived from a chain extender having only 2 or more imino groups into polyurethane include compounds having only 2 or more imino groups, and specifically, N, N'-di-t-. Butylethylenediamine, (1R, 2R) -N, N'-tert-butyl-1,2-bis (2-naphthyl) ethylenediamine, N'-cyclohexyl-2-methyl-N- (2-methylpropyl) -2 , 4-Pentanediamine and the like, but are not limited thereto.

((C) Chain extender having at least one amino group and one imino group)
Examples of the compound for introducing a structure derived from a chain extender having at least one amino group and one imino group into polyurethane include a compound having at least one amino group and one imino group, and specifically, aminoethylethanol. Examples thereof include, but are not limited to, amines, diethylenetriamines, triethylenetetramines, tetraethylenepentamines and pentaethylenehexamines.

When preparing the aqueous polyurethane resin dispersion of the present invention, it is preferable to use two or more chain extenders selected from the group consisting of (a), (b) and (c) as the chain extender.
Further, the molar ratio of amino groups to imino groups in the full chain extender is preferably 99: 1 to 1:99, more preferably 95: 5 to 5:95, and even more preferably 90:10 to 10:90. Particularly preferably, it is 80:20 to 20:80.
Within this range, an aqueous polyurethane resin dispersion having higher adhesion to the substrate can be obtained.

(Manufacturing method of aqueous polyurethane resin dispersion)
The aqueous polyurethane resin dispersion of the present invention has a structure derived from a polycarbonate polyol having the alicyclic structure, a structure derived from the polyisocyanate, a structure derived from the acidic group-containing polyol, and a structure derived from the chain extender. Aqueous polyurethane resin having is dispersed in an aqueous medium, for example,
A step (α) of reacting a polycarbonate polyol having an alicyclic structure, a polyisocyanate, and an acidic group-containing polyol to obtain a polyurethane prepolymer, and
The step of neutralizing the acidic group of the polyurethane prepolymer (β),
A step of dispersing the neutralized polyurethane prepolymer in an aqueous medium (γ) and a step of reacting the isocyanato group of the polyurethane prepolymer with a chain extender to obtain an aqueous polyurethane resin (δ).
It can be manufactured by a method including.

The step (α) is preferably carried out by adding at least one kind of aqueous organic solvent to the reaction system. The type of the aqueous organic solvent is not particularly limited as long as it is a liquid that is soluble in water and does not inhibit the urethanization reaction. Specific examples include an alkyl ether solvent of polyalkylene glycol such as dipropylene glycol dimethyl ether, and lactams such as N-ethylpyrrolidone.
The step of neutralizing the acidic group of the polyurethane prepolymer (β) and the step of dispersing the polyurethane prepolymer in the aqueous medium (γ) may be performed at the same time, or the step of dispersing the polyurethane prepolymer in the aqueous medium. The step (γ) and the step (δ) of reacting with the chain extender to obtain an aqueous polyurethane resin may be performed at the same time.

Further, in the step (δ) of reacting the isocyanato group of the polyurethane prepolymer with the chain extender to obtain an aqueous polyurethane resin, two or more kinds of chain extenders can be used in combination, but one kind is sequentially used one by one. A water-based polyurethane resin may be obtained, or two or more kinds may be used at the same time to obtain a water-based polyurethane resin.
The method of dispersing the polyurethane prepolymer in the aqueous medium in the step (γ) is not particularly limited, but it can be obtained by adding the urethane prepolymer or the urethane prepolymer solution while stirring the aqueous medium with a homomixer or a homogenizer. can. Further, an aqueous medium may be added to the polyurethane prepolymer solution to disperse the solution. At this time, the proportion of the polyurethane resin in the aqueous polyurethane resin dispersion is preferably 5 to 60% by weight, more preferably 20 to 50% by weight.

(Polyurethane prepolymer)
The polyurethane prepolymer of the present invention is obtained by reacting the polycarbonate polyol having the alicyclic structure with the polyisocyanate and the acidic group-containing polyol.
The ratio of the number of moles of the isocyanato group of the polyisocyanate to the number of moles of the total hydroxyl group of the polyol and the acid group-containing polyol is preferably 1.1 to 2.5, more preferably 1.2 to 2.2. Particularly 1.3 to 2.0 is preferable.

A catalyst can also be used when the polyisocyanate is reacted with the polyol and the acid group-containing polyol to obtain a polyurethane prepolymer.
The catalyst is not particularly limited, but is, for example, a metal such as a tin-based catalyst (trimethyltin laurate, dibutyltin dilaurate, etc.) or a lead-based catalyst (lead octylate, etc.), salts of organic and inorganic acids, an organic metal derivative, and an amine. Examples thereof include system catalysts (triethylamine, N-ethylmorpholin, triethylenediamine, etc.), diazabicycloundecene system catalysts, and the like. Of these, dibutyltin dilaurate is preferable from the viewpoint of reactivity.
The reaction between the polyisocyanate, the polyol, and the acid group-containing polyol may be carried out without a solvent or with the addition of an organic solvent. Examples of the organic solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, dioxane, dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, N-ethylpyrrolidone, ethyl acetate and the like. Of these, acetone, methyl ethyl ketone, and ethyl acetate are preferable because they can be removed by heating and reducing pressure after the polyurethane prepolymer is dispersed in water and further subjected to a chain extension reaction. Further, N-methylpyrrolidone and N-ethylpyrrolidone are preferable because they act as a film-forming auxiliary when preparing a coating film of the obtained aqueous polyurethane dispersion.
By reacting the polyisocyanate with the polyol and the acid group-containing polyol, a polyurethane prepolymer having an isocyanato group at the terminal can be obtained as a solvent-free or organic solvent solution. When the viscosity of the urethane prepolymer is high and it is difficult to disperse it in water, it can be diluted with an organic solvent to increase the dispersibility. As the organic solvent that can be used here, the solvent used in producing the polyurethane prepolymer can be used.

(Neutralizer)
In order to disperse the polyurethane prepolymer in water, a basic component can be added to the urethane prepolymer solution to neutralize the acidic groups derived from the acidic group-containing polyol contained in the polyurethane prepolymer.
Basic components that can be used for neutralization include trimethylamine, triethylamine, triisopropylamine, tributylamine, triethanolamine, N-methyldiethanolamine, N-phenyldiethanolamine, dimethylethanolamine, diethylethanolamine, and N-methylmorpholin. , Organic amines such as pyridine, inorganic alkalis such as sodium hydroxide and potassium hydroxide, ammonia and the like. Of these, organic amines are preferable, and triethylamine is particularly preferable. As a method of addition, a method of adding the basic component directly or as an aqueous solution to the polyurethane prepolymer solution is preferable, and the addition amount thereof is 0.5 to 2 times the equivalent of the acidic group in the polyurethane prepolymer. It is possible, and a 0.7 to 1.5 times equivalent is preferable, and a 0.85 to 1.3 times equivalent is particularly preferable.
A plurality of types of these neutralizers may be used in combination.

(Water-based medium)
The aqueous polyurethane resin dispersion of the present invention is in a form in which a polyurethane resin obtained by reacting a polyurethane prepolymer with a chain extender is dispersed in an aqueous medium. Examples of the aqueous medium include clean water, ion-exchanged water, distilled water, ultrapure water and the like. Above all, it is preferable to use ion-exchanged water in consideration of easy availability and unstable particles due to the influence of salt. Examples of the organic solvent include alcohol solvents such as methanol, ethanol, n-propanol and isopropanol; ketone solvents such as acetone and methyl ethyl ketone; polyalkylene glycols such as ethylene glycol, diethylene glycol and propylene glycol; and alkyl ethers of polyalkylene glycol. Solvent; Examples thereof include lactam solvents such as N-methyl-2-pyrrolidone and N-ethyl-2-pyrrolidone.
The aqueous medium is preferably contained in the range of 10% by mass to 90% by mass, more preferably in the range of 20% by mass to 80% by mass, in the total amount of the aqueous polyurethane resin dispersion of the present invention. Further, a plurality of types of water-based media may be used in combination.

(Paint composition, coating agent composition and ink composition)
The present invention also relates to a coating composition, a coating agent composition and an ink composition containing the aqueous polyurethane resin dispersion.
In addition to the above-mentioned aqueous polyurethane resin dispersion, other resins may be added to the coating composition, the coating agent composition and the ink composition of the present invention. Examples of other resins include polyester resin, acrylic resin, polyether resin, polycarbonate resin, polyurethane resin, epoxy resin, alkyd resin, polyolefin resin, vinyl chloride resin and the like. These may be used alone or in combination of two or more. Other resins preferably have one or more hydrophilic groups. Examples of the hydrophilic group include a hydroxyl group, a carboxy group, a sulfonic acid group, a polyethylene glycol group and the like.
The other resin is preferably at least one selected from the group consisting of polyester resin, acrylic resin, and polyolefin resin.

The polyester resin can usually be produced by an esterification reaction or a transesterification reaction between an acid component and an alcohol component. As the acid component, a compound usually used as an acid component in the production of the polyester resin can be used. As the acid component, for example, an aliphatic polybasic acid, an alicyclic polybasic acid, an aromatic polybasic acid and the like can be used.
The hydroxyl value of the polyester resin is preferably about 10 to 300 mgKOH / g, more preferably about 50 to 250 mgKOH / g, and even more preferably about 80 to 180 mgKOH / g. The acid value of the polyester resin is preferably about 1 to 200 mgKOH / g, more preferably about 15 to 100 mgKOH / g, and even more preferably about 25 to 60 mgKOH / g.

The weight average molecular weight of the polyester resin is preferably 500 to 500,000, more preferably 1,000 to 300,000, still more preferably 1,500 to 200,000.
As the acrylic resin, a hydroxyl group-containing acrylic resin is preferable. The hydroxyl group-containing acrylic resin comprises a hydroxyl group-containing polymerizable unsaturated monomer and another polymerizable unsaturated monomer copolymerizable with the hydroxyl group-containing polymerizable unsaturated monomer, for example, in a solution polymerization method in an organic solvent, in water. It can be produced by copolymerizing by a known method such as the emulsion polymerization method of.
The hydroxyl group-containing polymerizable unsaturated monomer is a compound having one or more hydroxyl groups and one or more polymerizable unsaturated bonds in one molecule. For example, (meth) acrylic acids such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate and 2 to 8 carbon atoms. Monoesters with dihydric alcohols; ε-caprolactone modified forms of these monoesters; N-hydroxymethyl (meth) acrylamides; allyl alcohols; (meth) acrylates with polyoxyethylene chains at the end of the molecule. And so on.

Examples of other polymerizable unsaturated monomers include compounds having a polyfunctional polymerizable unsaturated bond such as trimethylolpropane triacrylate and divinylbenzene.
The hydroxyl group-containing acrylic resin preferably has an anionic functional group. As for the hydroxyl group-containing acrylic resin having an anionic functional group, for example, as one kind of polymerizable unsaturated monomer, a polymerizable unsaturated monomer having an anionic functional group such as a carboxy group, a sulfonic acid group and a phosphoric acid group is used. Can be manufactured by.
The hydroxyl value of the hydroxyl group-containing acrylic resin is preferably about 1 to 200 mgKOH / g, more preferably about 2 to 100 mgKOH / g, and more preferably 3 to 60 mgKOH from the viewpoint of storage stability of the composition and water resistance of the obtained coating film. About / g is more preferable.
When the hydroxyl group-containing acrylic resin has an acid group such as a carboxy group, the acid value of the hydroxyl group-containing acrylic resin is preferably about 1 to 200 mgKOH / g from the viewpoint of water resistance of the obtained coating film and the like. About 150 mgKOH / g is more preferable, and about 5 to 100 mgKOH / g is even more preferable.
The weight average molecular weight of the hydroxyl group-containing acrylic resin is preferably 1,000 to 200,000, more preferably 2,000 to 100,000, and even more preferably in the range of 3,000 to 50,000. be.

Examples of the polyether resin include polymers or copolymers having an ether bond, and examples thereof include aromatics such as polyoxyethylene-based polyether, polyoxypropylene-based polyether, polyoxybutylene-based polyether, bisphenol A or bisphenol F. Examples thereof include polyethers derived from group polyhydroxy.
Examples of the polycarbonate resin include polymers produced from bisphenol, and examples thereof include bisphenol A and polycarbonate.
Examples of the polyurethane resin include resins having a urethane bond obtained by reacting various polyol components such as acrylic polyol, polyester polyol, polyether polyol, and polycarbonate polyol with polyisocyanate.
Examples of the epoxy resin include a resin obtained by the reaction of bisphenol and epichlorohydrin. Examples of bisphenol include bisphenol A and bisphenol F.

Alkyd resins include polybasic acids and polyhydric alcohols such as phthalic acid, terephthalic acid, and succinic acid, as well as fats and oils and fat fatty acids (soybean oil, flaxseed oil, palm oil, stearic acid, etc.), and natural resins (rosin, succinic acid, etc.). Etc.), and examples thereof include alkyd resins obtained by reacting with a modifying agent such as.
As the polyolefin resin, a polyolefin resin obtained by appropriately polymerizing or copolymerizing an olefin-based monomer with another monomer according to a normal polymerization method is water-dispersed using an emulsifier, or an olefin-based monomer is appropriately used as another monomer. Examples thereof include a resin obtained by emulsifying and polymerizing with the same. Further, depending on the case, a so-called chlorinated polyolefin-modified resin in which the above-mentioned polyolefin resin is chlorinated may be used.
Examples of the olefin-based monomer include ethylene, propylene, 1-butene, 3-methyl-1-butene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-hexene and 1-. Α-olefins such as decene and 1-dodecene; conjugated diene or non-conjugated diene such as butadiene, etilidennorbornene, dicyclopentadiene, 1,5-hexadiene and styrenes can be mentioned. A plurality of types of these monomers may be used in combination.
Examples of other monomers copolymerizable with the olefin-based monomer include vinyl acetate, vinyl alcohol, maleic acid, citraconic acid, itaconic acid, maleic anhydride, citraconic anhydride and itaconic anhydride. A plurality of types of these monomers may be used in combination.

The coating composition, coating agent composition and ink composition of the present invention may contain a curing agent, whereby a coating material or a multi-layer coating material or a coating obtained by using the coating material composition or the coating agent composition may be contained. It is possible to improve the water resistance of the film or printed matter.
As the curing agent, for example, amino resin, polyisocyanate, blocked polyisocyanate, melamine resin, carbodiimide and the like can be used. A plurality of types of curing agents may be used in combination.
Examples of the amino resin include a partially or fully methylolated amino resin obtained by reacting an amino component with an aldehyde component. Examples of the amino component include melamine, urea, benzoguanamine, acetoguanamine, steloganamin, spiroganamin, dicyandiamide and the like. Examples of the aldehyde component include formaldehyde, paraformaldehyde, acetaldehyde, benzaldehyde and the like.
Examples of the polyisocyanate include compounds having two or more isocyanato groups in one molecule, and examples thereof include hexamethylene diisocyanate and trimethylhexamethylene diisocyanate.
Examples of the blocked polyisocyanate include those obtained by adding a blocking agent to the isocyanato group of the above-mentioned polyisocyanate, and examples of the blocking agent include phenols such as phenol and cresol, and aliphatics such as methanol and ethanol. Alcohol-based, active methylene-based such as dimethyl malonate and acetylacetone, mercaptan-based such as butyl mercaptan and dodecyl mercaptan, acid amide-based such as acetanilide and acetate amide, lactam-based such as ε-caprolactam and δ-valerolactam, succinateimide Examples thereof include acidimide-based agents such as maleic acidimide, oxime-based agents such as acetoaldoxime, acetoneoxime and methylethylketooxime, and amine-based blocking agents such as diphenylaniline, aniline and ethyleneimine.
Examples of the melamine resin include methylol melamines such as dimethylol melamine and trimethylol melamine; alkyl ethers or condensates of these methylol melamines; and condensates of alkyl ethers of methylol melamine.

Coloring pigments, extender pigments, and brilliant pigments can be added to the coating composition, coating agent composition, and ink composition of the present invention.
Examples of the coloring pigment include titanium oxide, zinc flower, carbon black, molybdenum red, prusian blue, cobalt blue, azo pigment, phthalocyanine pigment, quinacridone pigment, isoindoline pigment, slene pigment, perylene pigment and the like. These may be used alone or in combination of two or more. In particular, it is preferable to use titanium oxide and / or carbon black as the coloring pigment.
Examples of the extender pigment include clay, kaolin, barium sulfate, barium carbonate, calcium carbonate, talc, silica, and alumina white. These may be used in combination of a plurality of types. In particular, it is preferable to use barium sulfate and / or talc as the extender pigment, and it is more preferable to use barium sulfate.
As the glitter pigment, for example, aluminum, copper, zinc, brass, nickel, aluminum oxide, mica, aluminum oxide coated with titanium oxide or iron oxide, mica coated with titanium oxide or iron oxide can be used. ..
The coating composition, coating agent composition and ink composition of the present invention may contain, if necessary, a thickener, a curing catalyst, an ultraviolet absorber, a light stabilizer, an antifoaming agent, a plasticizer, a surface conditioner, and a precipitation agent. It can contain ordinary additives such as inhibitors. These may be used in combination of a plurality of types.

The method for producing the coating composition, the coating agent composition and the ink composition of the present invention is not particularly limited, but a known production method can be used. Generally, the coating composition and the coating agent composition are produced by mixing the above-mentioned aqueous polyurethane resin dispersion with the above-mentioned various additives, further adding an aqueous medium, and adjusting the viscosity according to the application method. Will be done.
Examples of the material to be coated of the coating composition, the material to be coated of the coating agent composition, or the material to be applied of the ink composition include metals, plastics, inorganic substances, wood, etc. can.
An electrodeposition coating plate is an electrodeposition coating plate in which an object to be coated is immersed in a water-soluble paint and a DC voltage is applied using the object to be coated as a cathode (or anode) and the paint as an opposite electrode of the object to be coated. It is a laminated board in which a coating film is formed on an object. With electrodeposition coating, even an object to be coated with a complicated shape can be painted in detail and can be painted automatically and continuously, so large and complicated shapes such as automobile bodies can be applied. It is preferable as an undercoat coating method for an object to be coated, which has high rust resistance and is required. Further, it is economical because the use efficiency of the paint is extremely high as compared with other painting methods, and it is preferable as an industrial painting method. For example, cationic electrodeposition coating is performed by immersing an object to be coated in a cationic electrodeposition coating material having a cationic property as a cathode and applying a voltage.
Examples of the coating method of the coating composition or the coating method of the coating agent composition include bell coating, spray coating, roll coating, shower coating, and dip coating. Examples of the method of applying the ink composition include an inkjet printing method, a flexographic printing method, a gravure printing method, a reverse offset printing method, a sheet-fed screen printing method, and a rotary screen printing method.

It is preferable that the coating composition, the coating agent composition and the ink composition are applied to the material to be applied and then heat-cured to obtain a coating film and a coating.
Examples of the heating method include a heating method using its own reaction heat, a heating method for actively heating a coating composition, a coating agent composition, an ink composition, and an applied material. Examples of the positive heating include a method in which a coating composition, a coating agent composition, an ink composition and an applied material are placed in a hot air oven, an electric furnace, or an infrared induction heating furnace to heat them.
The heating temperature is preferably 40 to 200 ° C, more preferably 60 to 160 ° C. By heating at such a temperature, drying can be performed more efficiently. The heating time is preferably 0.0001 to 20 hours, more preferably 1 to 10 hours. By setting such a heating time, a polyurethane resin film having higher hardness can be obtained. Drying conditions for obtaining the polyurethane resin film include, for example, heating at 120 ° C. for 3 to 10 seconds.
In particular, in the present invention, it is possible to form a coating film having high adhesion to a substrate at a relatively low temperature of about 80 to 90 ° C.
The thickness of the coating film after curing is not particularly limited, but is preferably 1 to 100 μm, and more preferably 3 to 50 μm.

(Polyurethane resin film)
The present invention further relates to a polyurethane resin film obtained from the aqueous polyurethane resin dispersion.
A polyurethane resin film can be obtained by using an aqueous polyurethane resin dispersion. A polyurethane resin film can be obtained by applying an aqueous polyurethane resin dispersion to a releasable substrate, drying and curing it by means such as heating, and then peeling the cured product of the polyurethane resin from the releasable substrate. ..
Examples of the heating method include a heating method using its own reaction heat and a heating method in which the reaction heat and positive heating of the mold are used in combination. Examples of positive heating of the mold include a method of heating the mold in a hot air oven, an electric furnace, or an infrared induction heating furnace.
The heating temperature is preferably 40 to 200 ° C, more preferably 60 to 160 ° C. By heating at such a temperature, drying can be performed more efficiently. The heating time is preferably 0.0001 to 20 hours, more preferably 1 to 10 hours. By setting such a heating time, a polyurethane resin film having higher hardness can be obtained. Drying conditions for obtaining the polyurethane resin film include, for example, heating at 120 ° C. for 3 to 10 seconds.

Next, the present invention will be specifically described with reference to examples, but the scope of the present invention is not limited thereto.

(Evaluation of adhesion to substrate)
The aqueous polyurethane resin composition was applied onto each of a 70 mm × 50 mm steel sheet and dried at 80 ° C. for 60 minutes to prepare a metal substrate coated with the aqueous polyurethane resin dispersion. Eleven vertical and horizontal cuts were made in the obtained cured film at intervals of 2 mm to prepare 100 cells. The cellophane tape was applied to the entire mass, rubbed with an eraser, adhered well, and then the cellophane tape was vigorously peeled off to evaluate the adhesion to the substrate.
It was terminated when even one square was peeled off, and if it was not peeled off, this operation was repeated up to 10 times. The number of molecules remaining on the surface of the substrate without peeling and the number of tests performed until peeling (number in parentheses) were used as the evaluation results.

[Example 1]
ETERNALCOLL UM90 (1/3) (registered trademark; polycarbonate diol manufactured by Ube Kosan Co., Ltd .; number average molecular weight 907; hydroxyl value 123.7 mgKOH / g; polyol component 1,4- Cyclohexanedimethanol: Polycarbonate diol obtained by reacting a polyol mixture having a molecular ratio of 1,6-hexanediol = 1: 3 with a carbonic acid ester) 319.52 g (0.352 mol) and 2,2-di. 45.89 g (0.342 mol) of methylolpropionic acid, 240.05 g (0.915 mol) of hydrogenated MDI, 63.62 g (0.254 mol) of MDI were added to dibutyltin dilaurylate in N-ethylpyrrolidone (dibutyltin dilaurylate). 0.5 g) In the presence of a nitrogen atmosphere, the mixture was heated at 80 to 90 ° C. for 5 hours. The isocyanato group content at the end of the urethanization reaction was 4.05% by weight. After the reaction mixture was brought to 80 ° C., 34.67 g of triethylamine was added, and the mixture was stirred for 30 minutes. Of the reaction mixture, 404.4 g was extracted and placed in 513.6 g of water with vigorous stirring, and then 15.0 g of 2-methyl-1,5-pentanediamine and 3.8 g of diethylenetriamine were added as chain extenders to add aqueous solution. A polyurethane resin dispersion was obtained.

[Comparative Example 1]
ETERNALCOLL UM90 (1/3) (registered trademark; polycarbonate diol manufactured by Ube Kosan Co., Ltd .; number average molecular weight 900; hydroxyl value 124.7 mgKOH / g; polyol component 1,4 -Cyclohexanedimethanol: Polycarbonate diol obtained by reacting a polyol mixture having a molecular ratio of 1,6-hexanediol = 1: 3 with a carbonic acid ester) 176.3 g (0.196 mol) and 2,2-. 26.3 g (0.196 mol) of dimethylol propionic acid and 169.7 g (0.647 mol) of hydrogenated MDI in the presence of dibutyltin dilaurylate (0.3 g) in N-methylmethylpyrrolidone, in a nitrogen atmosphere. Underneath, it was heated at 80-90 ° C. for 5 hours. The isocyanato group content at the end of the urethanization reaction was 3.90% by weight. After the reaction mixture was brought to 80 ° C., 19.9 g of triethylamine was added, and the mixture was stirred for 30 minutes. Of the reaction mixture, 416.5 g was extracted and placed in 527.5 g of water with strong stirring, and then 19.64 g of a 2-methyl-1,5-pentanediamine aqueous solution was added as a chain extender to add an aqueous polyurethane resin dispersion. Got

From the comparison between Example 1 and Comparative Example 1, it can be seen that the aqueous polyurethane resin dispersion of the present invention is applied to the substrate and dried, and the obtained coating film has excellent adhesion to the substrate.

The aqueous polyurethane resin dispersion of the present invention can be widely used as a raw material for paints, coating agents, primers, adhesives, inks, films and the like.

Claims (10)

In an aqueous polyurethane resin dispersion having a structure derived from a polycarbonate polyol having an alicyclic structure, a structure derived from a polyisocyanate, a structure derived from an acidic group-containing polyol, and a structure derived from a chain extender.
The chain extender is (a) a chain extender having only two or more amino groups, and (c) a chain extender having at least one amino group and one imino group.
An aqueous polyurethane resin dispersion having a partial structure represented by the following formulas (1) and (2) (however, a polyurethane resin having a polymerizable unsaturated bond and a compound having a polymerizable unsaturated bond are dispersed in an aqueous medium. Excluding the aqueous polyurethane resin dispersion).

The partial structure shown in the above formula (1) is
A partial structure produced by the reaction of an isocyanato group with an amino group of (a) a chain extender having only two or more amino groups, or a chain extender having at least one isocyanato group and (c) an amino group and an imino group. A partial structure produced by the reaction with an amino group,
The aqueous polyurethane resin dispersion according to claim 1. The aqueous polyurethane resin dispersion according to claim 1 or 2 , wherein the molar ratio of the formula (1) to the formula (2) is 99: 1 to 1:99. The aqueous polyurethane resin dispersion according to any one of claims 1 to 3 , wherein the polyisocyanate-derived structure has a structure derived from an aliphatic polyisocyanate and a structure derived from an aromatic polyisocyanate. .. A step (α) of reacting a polycarbonate polyol or polyisocyanate having an alicyclic structure with an acidic group-containing polyol to obtain a prepolymer.
The step of neutralizing the acidic group in the prepolymer (β) and
The step of dispersing the neutralized prepolymer in the aqueous dispersion (γ),
The method for producing an aqueous polyurethane resin dispersion according to any one of claims 1 to 4 , which comprises a step (δ) of reacting a prepolymer dispersed in an aqueous medium with a chain extender. The method for producing an aqueous polyurethane resin dispersion according to claim 5 , wherein at least one kind of aqueous organic solvent is added in the step (α) for obtaining the prepolymer. A coating composition containing the aqueous polyurethane resin dispersion according to any one of claims 1 to 4 . A coating agent composition containing the aqueous polyurethane resin dispersion according to any one of claims 1 to 4 . An ink composition containing the aqueous polyurethane resin dispersion according to any one of claims 1 to 4 . A polyurethane resin film obtained by drying and curing a composition containing the aqueous polyurethane resin dispersion according to any one of claims 1 to 4 .