JP2023026829A - Resin composition, polyurea resin, paint, and coating film - Google Patents

Abstract

To provide a resin composition for obtaining a polyurea resin which has various excellent characteristics while having an excellent pot life and for which various coating methods are usable.SOLUTION: Provided is a resin composition comprising a blocked (poly)isocyanate compound (a) and a polyamine (b) containing a primary amino group. The resin composition has a viscosity of 100-5,000,000 mPa s when allowed to stand at 25°C for 12 hours and cures at 60-200°C. The polyamine (b) containing a primary amino group is preferably one or more selected from polyvalent aromatic amines, polyether polyamines, polyethylene imines, ethylene amines, and aliphatic polyamines.SELECTED DRAWING: None

Description

The present invention relates to resin compositions, polyurea resins, paints, and coating films.

Polyurea resins are known to exhibit excellent physical properties, water resistance, chemical resistance, and the like, and are widely used for exterior walls of buildings, floor materials, and the like. Isocyanate compounds and polyamines, which are raw materials for polyurea resins, are known to have very high reactivity and harden at room temperature (15 to 30° C.) in a few seconds to ten and several seconds to gel and solidify. For this reason, when using a polyurea resin, it is not possible to adopt a so-called two-liquid type product, in which the raw materials are mixed and the coating is applied in the time it takes for the mixture to harden. Therefore, in order to apply a polyurea resin, a method called spray coating, in which the raw materials are separately heated and mixed immediately before spraying, has been generally used.

While the spray coating method enables efficient coating over a wide area, it is difficult to coat a narrow area. Moreover, since the mixed raw material scatters, it may be unfavorable to the human body and the surrounding environment.

In order to solve this problem, a technology is known that uses an amine called aspartate to extend the pot life of polyurea resin (the time during which viscosity can be maintained for use in coating) and can be used for hand coating. (Patent Document 1).

There is also known a technique of producing a two-liquid polyurethane urea whose reaction progress can be controlled by using a blocking agent for an isocyanate compound (Patent Document 2).

Patent No. 3415201 WO2019/189944

However, the physical properties of the coating film obtained in Patent Document 1 are inferior to those produced by the spray coating method.
In Patent Document 2, an isocyanate compound whose reactivity is suppressed compared to other isocyanates is used by using a blocking agent. The obtained polyurea resin is inferior in physical properties when used as a coating film, as compared with a coating film produced by a spray coating method.

Furthermore, both of the polyurea resins of Patent Documents 1 and 2 are difficult to adjust the pot life, and in applications where coating is performed manually by contractors, etc., loss occurs in terms of working time or materials.

The object of the present invention is to secure a sufficient pot life at room temperature, to be able to handle easily by brush coating or roller coating, to allow the curing reaction to proceed by heating, and to obtain physical properties of the coating film. An object of the present invention is to provide a resin composition for obtaining a polyurea resin excellent in

The present inventors have found that the above problems can be solved by using a polyamine having a specific structure and a blocked (poly)isocyanate compound, and completed the present invention.
That is, the gist of the present invention is the following (1) to (8).
(1) containing a blocked (poly)isocyanate compound (a) and a polyamine (b) containing a primary amino group, and having a viscosity of 100 to 5,000,000 mPa· when allowed to stand at 25°C for 12 hours; s and cures at 60 to 200°C.
(2) The resin composition of (1), wherein the polyamine (b) containing a primary amino group is one or more selected from polyvalent aromatic amines, polyether polyamines, polyethyleneimines, ethyleneamines and aliphatic polyamines. thing.
(3) The resin composition of (1) or (2), wherein the isocyanate constituting the blocked (poly)isocyanate compound (a) is an aromatic (poly)isocyanate and/or an aliphatic (poly)isocyanate. .
(4) The resin composition according to any one of (1) to (3), which has an organic solvent content of 30% by mass or less.
(5) A polyurea resin obtained by curing the resin composition of any one of (1) to (4).
(6) A paint containing the resin composition according to any one of (1) to (4).
(7) The coating of (5) applied by brushing, roller coating, or troweling.
(8) A coating film made of the paint according to (6) or (7).

The present invention contains a blocked (poly)isocyanate compound (a) and a polyamine (b) having a primary amino group, and is capable of suppressing the progress of the curing reaction at room temperature while maintaining a moderate heating temperature. Then the curing reaction proceeds. As a result, it is possible to obtain a polyurea resin capable of extending the pot life and forming a coating film having excellent physical properties.

The resin composition of the present invention contains a blocked (poly)isocyanate compound (a) and a polyamine (b) containing a primary amino group.

A blocked (poly)isocyanate compound is obtained by blocking the isocyanate groups of (poly)isocyanate with a blocking agent. By using the blocked (poly)isocyanate compound (a), it is possible to suppress the reactivity with the polyamine (b) having a primary amino group and obtain a resin composition in which the curing reaction at room temperature is suppressed. . Also, by using a blocked (poly)isocyanate compound, the effects on the human body and the environment are reduced.

In the resin composition of the present invention, the equivalent ratio of polyamine to blocked isocyanate groups (NCO/NH ₂ ) between component (a) and component (b) is preferably 0.85 to 1.15, and 0.85 to 1.15. 90 to 1.05 is more preferred, and 0.97 to 1.03 is even more preferred. If the equivalent ratio is less than 0.85, the physical properties of the resulting polyurea resin coating film may be deteriorated. It may become more likely.

(Poly)isocyanate, which constitutes the blocked (poly)isocyanate compound, is a compound having two or more isocyanate groups, and may be in the form of a monomer, an oligomer, or a polymer.

Examples of (poly)isocyanates include aromatic, aliphatic and/or alicyclic polyisocyanate monomers, isocyanate-terminated prepolymers obtained by reacting these with polyamines and polyols, and modified products thereof (allophanate modified products, urea modification, carbodiimide modification, burette modification, uretdione modification, isocyanurate modification, etc.) and the like.

Aromatic (poly)isocyanates and aliphatic (poly)isocyanates include 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, 1,5-naphthylene diisocyanate, 1,6 -hexamethylene diisocyanate, 1,4-tetramethylene diisocyanate, 2-methylpentane-1,5-diisocyanate, 3-methylpentane-1,5-diisocyanate, 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate , 2,6-diisocyanatomethylcaproate, lysine diisocyanate, trioxyethylene diisocyanate and the like.

Alicyclic (poly)isocyanates include 1,4-bis(isocyanatomethyl)cyclohexane, 4,4′-methylenebis(cyclohexylisocyanate), methyl-2,4-cyclohexanediisocyanate, and methyl-2,6-cyclohexanediisocyanate. , 1,3-bis(isocyanatomethyl)cyclohexane, 1,3-bis(isocyanatoethyl)cyclohexane, 1,4-bis(isocyanatoethyl)cyclohexane, 2,5- or 2,6-bis(isocyanatomethyl) ) hydrogenated norbornane (NBDI) and aromatic (poly)isocyanate.

Among them, aromatic (poly)isocyanates and aliphatic (poly)isocyanates are preferred from the viewpoint of curing reactivity with polyamines having primary amino groups during heating, and 2,4-toluene diisocyanate, 2,6 - toluene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, 1,5-naphthylene diisocyanate, 1,6-hexamethylene diisocyanate, lysine isocyanate, 4,4'-methylenebis(cyclohexyl isocyanate) are preferred, 2,4-toluene diisocyanate, More preferred are 2,6-toluene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate and 1,6-hexamethylene diisocyanate. Moreover, these may use two or more types together.

Examples of isocyanate-terminated prepolymers include those obtained by using the above (poly)isocyanate monomer and one or more selected from the high-molecular-weight polyols or polyamines described below as main components, and if necessary, in combination with low-molecular-weight polyols or polyamines. be done.

In order to obtain an isocyanate-terminated prepolymer, for example, a (poly)isocyanate monomer and a polyol or polyamine are reacted by a known method under a nitrogen gas atmosphere, and if necessary, in the presence of a solvent or a known catalyst such as dioctyltin dilaurate. and react at 60-100°C.
The isocyanate group/hydroxyl group and isocyanate group/amino group equivalent ratios in the reaction for obtaining the isocyanate-terminated prepolymer can be appropriately selected according to the properties of the prepolymer and the physical properties of the polyurea resin after the curing reaction. is preferably 1.5/1.0 to 2.5/1.0. .

Examples of low-molecular-weight polyols include compounds having two or more hydroxyl groups and having a number-average molecular weight of less than 400. Specific examples include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butylene glycol, 1,3-butylene glycol, 1,2-butylene glycol, 1,5-pentanediol, 1,6 - hexanediol, neopentyl glycol, alkane (7-22) diol, diethylene glycol, triethylene glycol, dipropylene glycol, 3-methyl-1,5-pentanediol, alkane-1,2-diol (C17-20), 1,3- or 1,4-cyclohexanedimethanol and mixtures thereof, 1,4-cyclohexanediol, hydrogenated bisphenol A, 1,4-dihydroxy-2-butene, 2,6-dimethyl-1-octene, 3, dihydric alcohols such as 8-diol; and trihydric alcohols such as glycerin and trimethylolpropane.
In addition, polyalkylene oxides having a number average molecular weight of less than 400 (including random and/or block copolymers of two or more alkylene oxides) obtained by adding alkylene oxides such as ethylene oxide and propylene oxide to these alcohols. ).

Examples of high-molecular-weight polyols include compounds having two or more hydroxyl groups and having a number average molecular weight of 400 or more. Specific examples include polyether polyols, polyester polyols, polycarbonate polyols, polyurethane polyols, epoxy polyols, vegetable oil polyols, polyolefin polyols, and acrylic polyols.

Examples of low-molecular-weight polyamines include compounds having a number-average molecular weight of less than 600 and having two or more primary or secondary amino groups in total. Specific examples thereof include ethylenediamine, 1,3-propanediamine, 1,4-butanediamine, 1,3-butanediamine, 1,2-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, Alkanediamines such as dimer diamine, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 1,5-naphthalenediamine, 1,8-naphthalenediamine, o-xylylenediamine, m-xylylenediamine, p- Aromatic diamines such as xylylenediamine, polyether diamines such as triethylene glycol diamine, trimethylolpropane poly(oxypropylene)triamine, methoxypoly(oxyethylene/oxypropylene)-2-propylamine, diethylenetriamine, triethylenetetramine, tetra Examples include ethylene amines such as ethylene pentamine, polyethyleneimine, Michael adducts of maleic acid diesters and primary amines, reactants of epoxy compounds and primary amines, and the like.
In addition, polyalkylene oxides having a number average molecular weight of less than 400 obtained by adding alkylene oxides such as ethylene oxide and propylene oxide to these polyamines (random and/or block copolymers of two or more alkylene oxides are included. ).

High-molecular-weight polyamines are compounds having two or more primary or secondary amino groups and having a number average molecular weight of 600 or more. Examples include amine reactants.

As the (poly)isocyanate, an isocyanate-modified product can also be used. Specific examples thereof include biuret, isocyanurate, adduct, polymeric and the like. Two or more of these may be mixed depending on the viscosity of the resin composition and the physical properties of the resulting polyurea resin.

Specific examples of blocking agents include alcohols such as methanol, ethanol and 2-methyl-2-propanol; phenols such as phenol, cresol and p-chlorophenol; thiols such as benzenethiol and 1-dodecanethiol; Lactams such as -caprolactam, oximes such as methyl ethyl ketone oxime, active methylene compounds such as ethyl acetoacetate, methyl acetoacetate and malonate diesters, and pyrazole compounds such as pyrazole and 3,5-dimethylpyrazole. When a triazole-based compound or imidazole-based blocking agent is used, the curing reaction between component (a) and component (b) may not be suppressed, and the reaction may proceed even at room temperature, which is not preferable. There is

The blocked (poly)isocyanate compound (a) used in the resin composition of the present invention can be produced by a known method.
For example, it can be obtained by adding a blocking agent to the above (poly)isocyanate and reacting it at 30 to 90° C. in a nitrogen gas atmosphere. The progress of the reaction is confirmed by the absorption intensity of the isocyanate group (near 2270 cm ⁻¹ ) in the infrared absorption spectrum, and the point of disappearance is defined as the end point. The reaction can be carried out by adding a solvent or plasticizer depending on the viscosity of the blocked (poly)isocyanate compound and the purpose.

The blocking agent/isocyanate group equivalent ratio in component (a) is preferably 0.90 to 1.50, more preferably 0.95 to 1.30, and even more preferably 0.95 to 1.10. If it is 0.90 or less, the remaining isocyanate groups may instantly react with the polyamine to increase the viscosity. If it exceeds 1.50, the physical properties of the coating film obtained may deteriorate, or the curing temperature may become high.

A polyamine (b) containing a primary amino group is one that reacts with a blocked (poly)isocyanate compound. Component (b) includes aromatic, aliphatic and/or alicyclic primary polyamines.

Examples of aromatic primary polyamines include benzenediamines such as benzenediamine, 2,4-diethyl-6-methyl-1,3-benzenediamine and toluenediamine, 4,4'-diaminobiphenyl, 2,2'-dimethyl Examples include diaminobiphenyls such as biphenyl-4,4'-diamine, 4,4'-diaminodiphenyl ether, 2,2'-bis(trifluoromethyl)benzidine, bis(4-aminophenyl)sulfone and the like.

Aliphatic primary polyamines include 1,2-diaminoethane (ethylenediamine), 1,3-diaminopropane, 1,4-diaminobutane (1,4-tetramethylenediamine), 1,5-diaminopentane (1 ,5-pentamethylenediamine), 2-methyl-1,5-pentanediamine, 1,6-diaminohexane (1,6-hexamethylenediamine), 1,7-diaminoheptane, 1,8-diaminooctane, 1 ,9-diaminononane, 1,10-diaminodecane, 1,12-diaminododecane, 2,2,4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, tetramethylenediamine, 1,2,3 -triaminopropane, triaminohexane, triaminononane, triaminododecane, 1,8-diamino-4-aminomethyloctane, 1,3,6-triaminohexane, 1,6,11-triaminoundecane, 3 -aminomethyl-1,6-diaminohexane, diethylenetriamine, triethylenetetramine, polyethyleneimine and the like.

Polyether polyamines are included as aliphatic primary polyamines. Specific examples include α,ω-bis(2-aminopropyl ether)poly(propylene glycol) and α,ω-bis(3-aminopropyl)poly(oxytetramethylene).

Alicyclic primary polyamines include diaminocyclobutane, isophoronediamine (3-aminomethyl-3,5,5-trimethylcyclohexylamine), 1,2-diaminocyclohexane, 1,3-diaminocyclohexane, 1,4- diaminocyclohexane, methyl-2,4-cyclohexanediamine, methyl-2,6-cyclohexanediamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 4,4′-methylenebis( cyclohexylamine), 4,4′-methylenebis(2-methylcyclohexylamine), 2,5-bis(aminomethyl)bicyclo[2,2,1]heptane, 2,6-bis(aminomethyl)bicyclo[2, 2,1]heptane, triaminocyclohexane, and the like.

The resin composition of the present invention may contain an aliphatic and/or alicyclic secondary polyamine or polyol compound for the purpose of adjusting the physical properties and pot life of the coating film.
Examples of secondary polyamines include Michael adducts of maleic acid diesters and primary amines, reactants of epoxy compounds and primary amines, and the like. Polyol compounds include polyether polyols, polyester polyols, polycarbonate polyols, polyurethane polyols, epoxy polyols, vegetable oil polyols, polyolefin polyols, and the like.

The amount of the aliphatic and/or alicyclic secondary polyamine or polyol compound added is preferably such that the equivalent ratio to the primary amine is 0 to 0.2. If the equivalent ratio exceeds 0.2, the physical properties derived from the reaction product of primary amine and isocyanate may be impaired.

The resin composition of the present invention may contain a catalyst in order to improve the physical properties of the coating film to be obtained and to adjust the pot life and curing temperature.
Specific examples of catalysts include triethylamine, tributylamine, triethylenediamine, 2-dimethylaminoethyl ether, diazabicycloundecene, tertiary amines such as N-methylmorpholine, dibutyltin diacetate, dibutyltin laurate, 3-dibutyltin metal-based catalysts such as acetoxytetrabutylstannoxane, tin octenoate, tin chloride, butyl tin trichloride, bismuth trichloride, bismuth octenoate, tetrakis(2-ethylhexyl) titanate, tetrabutoxytitanium, and metal salts of acetoacetic acid; A quaternary ammonium salt and the like are included.

The resin composition of the present invention can be produced by mixing component (a), component (b), and, if necessary, other components in the above proportions.

The resin composition of the present invention is reacted and cured at an appropriate heating temperature. Thereby, it can be set as a polyurea resin.
The curing reaction temperature is 60 to 200°C, preferably 80 to 180°C, more preferably 80 to 150°C. If the curing temperature is less than 60°C, the curing reaction may be difficult to occur, and if it exceeds 200°C, the resin composition may not only oxidize or decompose, but also work safety may be disadvantageous. .

Since the resin composition of the present invention undergoes a curing reaction by heating, when it is applied to obtain a polyurea coating film, it is less likely to be affected by moisture contained in the coating substrate, and foaming is suppressed.

As the apparatus for heating the resin composition of the present invention, a known apparatus can be used in consideration of the viscosity of the polyurea resin to be obtained, the shape of the adherend, and the like. Specific examples of heating devices include heating rollers, roller heaters, polyimide heaters, infrared radiation heaters, polyimide heaters, high-temperature air heaters, heat guns, dryers, drying ovens, baking ovens, constant temperature dryers, and constant temperature ovens.

The resin composition of the present invention is liquid in shape and can be applied by hand coating or the like, and can be applied even if it does not substantially contain an organic solvent in normal coating. However, in order to adjust the viscosity, film thickness, coating speed, etc., an organic solvent may be contained within a range that does not impair the effects of the present invention.
The content of the organic solvent is preferably 30% by mass or less, more preferably 0 to 15% by mass, based on the total amount of the resin composition. 0 to 5% by mass is more preferable, and 0 to 3% by mass is particularly preferable. If the content of the organic solvent exceeds 30%, the effect of the present invention, namely the reduction of the burden on the human body and the environment, may be impaired.
When the content of the organic solvent is 30% by mass or less, the environmental load can be reduced compared to ordinary solvent-based paints and coating agents.

Examples of organic solvents include esters such as ethyl acetate and butyl acetate; ketones such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene and xylene; Examples include glymes such as diethyl ether and diisopropylene glycol dimethyl ether, and glycol esters such as ethylene glycol monomethyl ether acetate and propylene glycol monomethyl ether acetate. These organic solvents can be used alone or in combination of two or more.

The resin composition of the present invention includes, for example, known plasticizers, colorants such as pigments and dyes, antifoaming agents, ultraviolet absorbers, light stabilizers, antioxidants, inorganic fillers such as calcium carbonate and talc, and wetting agents. Dispersants, anti-settling agents and the like may be included.
The content can be any value to achieve the application and purpose.

The resin composition of the present invention preferably has a viscosity of 100 to 500,000 mPa·s, more preferably 500 to 300,000 mPa·s.

The resin composition of the present invention is inhibited from curing reaction at room temperature. As an indicator, the viscosity of the resin composition when left standing at 25° C. for 12 hours is 100 to 5,000,000 mPa·s, preferably 1,000 to 2,500,000 mPa·s.

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

First, methods for measuring and evaluating various physical properties will be described.
(1) Isocyanate content It was determined according to JIS K 7301 di-n-butylamine hydrochloric acid back titration method.

(2) Amine content It was determined according to the indicator titration method of JIS K 7237.

(3) Equivalent ratio of NCO/ _NH2 Calculated from the content ratios obtained in (1) and (2) above.

(4) The end point of the reaction between the (poly)isocyanate compound and the blocking agent was measured at around 2270 cm ⁻¹ by a Fourier transform infrared spectrophotometer (FT-IR) (trade name: FT/IR-300) manufactured by JASCO Corporation. The point at which the absorption spectrum of the isocyanate group disappeared was taken as the point.

(5) Viscosity BROOKFIELD ENGINEERING LABORATORIES, INC. Rotational viscosity (mPa·s) at a temperature of 25° C. was measured using a Brookfield DIAL VISCOMETER Model LVT, a Brookfield viscometer manufactured by the company.

(6) Viscosity after standing for 12 hours The viscosity of the resin composition after standing at 25°C for 12 hours was measured in the same manner as in (5) above.

(7) Acid Resistance The resulting resin composition was applied to a metal plate with a baker applicator to a thickness of 1 mm and cured at 140° C. for 30 minutes. After that, it was cut into a size of 20 mm×20 mm×1 mm to obtain a test piece, which was immersed in a 10% by mass sulfuric acid aqueous solution at 25° C. for 60 days. After that, the case where none of swelling, cracking, softening, or elution occurred in the test piece was rated as ◯, and the case where one or more of them occurred was rated as x.

(8) Alkali resistance A test piece obtained in the same manner as in (7) above was immersed in a saturated aqueous solution of calcium hydroxide at 25°C for 60 days. After that, the case where none of swelling, cracking, softening, or elution occurred in the test piece was rated as ◯, and the case where one or more of them occurred was rated as x.

(9) Tensile strength A test piece obtained in the same manner as in (7) above is stretched using a tensile tester (Intesco Precision Universal Material Testing Machine 2020) until the test piece breaks, and the maximum was taken as the tensile strength.
The measurement was performed in an atmosphere of 20° C. and 65% RH, with a distance between chucks of 10 mm and a tensile speed of 100 mm/min. The measurement was performed with 5 samples, and the average value was adopted.

(10) Concrete Adhesion Strength A resin composition was applied to a mortar adherend defined in JIS A 1439:2016 so as to have a thickness of 1 mm, and cured at 140° C. for 30 minutes. Then, the adhesion strength was measured using an adhesion tester (RQ-40A manufactured by Sanko Techno Co., Ltd.).
The measurement was performed with 5 samples, and the average value was adopted.

(11) Storage stability (pot life)
15 g of the resulting resin composition was weighed into a glass container (100 mL) and mixed until it appeared uniform. After that, it was stored in a constant temperature bath set at a temperature of 25° C., and the time until fluidity was lost was visually confirmed to determine the pot life.
Storage stability was determined according to the following criteria.
◎: Pot life is 24 hours or more ○: Pot life is 18 hours or more and less than 24 hours △: Pot life is 12 hours or more and less than 18 hours ×: Pot life is less than 12 hours In practice, pot life is 12 hours hours or longer, preferably 18 hours or longer.

Raw materials used in Examples and Comparative Examples are shown below. The raw materials were used as they were without purification or distillation.

<(Poly)isocyanate>
MDI: diphenylmethane diisocyanate (weight average molecular weight 250, manufactured by Tokyo Chemical Industry Co., Ltd.)
TDI: toluene diisocyanate (2,4-, 2,6-mixture) (weight average molecular weight 174, manufactured by Tokyo Chemical Industry Co., Ltd.)
HDI: 1,6-hexamethylene diisocyanate (weight average molecular weight 168, manufactured by Tokyo Chemical Industry Co., Ltd.)
XDI: m-xylylene diisocyanate (weight average molecular weight 188, Mitsui Chemicals Takenate 500)
H12MDI: hydrogenated diphenylmethane diisocyanate (weight average molecular weight 262, manufactured by Tokyo Chemical Industry Co., Ltd.)
H6XDI: hydrogenated xylylene diisocyanate (weight average molecular weight 194, manufactured by Tokyo Chemical Industry Co., Ltd.)
IPDI: isophorone diisocyanate (weight average molecular weight 222, manufactured by Tokyo Chemical Industry Co., Ltd.)
24A-100: Biuret-modified HDI (manufactured by Asahi Kasei Corporation, NCO content 23.5%)
TPA-100: HDI isocyanurate modified product (manufactured by Asahi Kasei Corporation, NCO content 23.1%)
MR-200: Polymeric modified MDI (manufactured by Tosoh Corporation, NCO content 31.2%)

<Polyol>
P-2010: Poly(3-methyl-1,5-pentanediol) adipate diol (Kuraray Polyol P-2010 manufactured by Kuraray Co., Ltd., number average molecular weight 2,000)

<Polyamine having a secondary amino group>
DMEDA: N,N'-dimethylethylenediamine (manufactured by Tokyo Chemical Industry Co., Ltd., weight average molecular weight 88)
2MP: 2-methylpiperazine (manufactured by Tokyo Kasei Co., Ltd., weight average molecular weight 100)
NH1220: Desmophen NH1220 (manufactured by Covestro, weight average molecular weight 460, amine value 244 mgKOH/g)

<Blocking agent>
MEKO: methyl ethyl ketone oxime (manufactured by Tokyo Chemical Industry Co., Ltd., weight average molecular weight 87)
DMP: dimethylpyrazole (manufactured by Tokyo Chemical Industry Co., Ltd., weight average molecular weight 96)
DEM: diethyl malonate (manufactured by Tokyo Chemical Industry Co., Ltd., weight average molecular weight 160)
E-CAP: ε-caprolactam (manufactured by Tokyo Chemical Industry Co., weight average molecular weight 113)
TA: 1,2,4-triazole (manufactured by Tokyo Chemical Industry Co., weight average molecular weight 69)

<Polyamine Having Primary Amino Group>
DETDA: diethyl toluenediamine (manufactured by Mitsui Chemicals Fine Co., Ltd., weight average molecular weight 178)
DEEDA: N,N'-diethylethylenediamine (manufactured by Tokyo Chemical Industry Co., Ltd., weight average molecular weight 116)
D400: Polyetheramine (manufactured by Mitsui Fine Chemicals, weight average molecular weight 400, primary amino group weight 4.5 mmol/g)
SP-018: polyethyleneimine (manufactured by Nippon Shokubai Co., Ltd., weight average molecular weight 1800, primary amino group content 6.7 mmol/g, secondary amino group content 6.7 mmol/g)
TETA: triethylenetetramine (manufactured by Tokyo Chemical Industry Co., Ltd., weight average molecular weight 146)
HMDA: hexamethylenediamine (manufactured by Tokyo Chemical Industry Co., Ltd., weight average molecular weight 116)
MBCHA: 4,4'-methylenebiscyclohexylamine (manufactured by Tokyo Chemical Industry Co., weight average molecular weight 210)

<Production of isocyanate-terminated prepolymer (A) using polyol>
The inside of a four-necked flask equipped with a stirrer, thermometer, reflux condenser and nitrogen blowing tube was purged with nitrogen, and 358 g of P-2010 and 92 g of MDI were added at room temperature. Then, 50 g of diglyme was added, and the temperature was gradually raised to 90° C. for 5 hours to react. The reaction was terminated by IR confirming that the theoretical isocyanate content had been reached. The resulting prepolymer had a resin concentration of 90%, an NCO content of 3.2% and a viscosity of 9,200 mPa·s/25°C.

<Production of isocyanate-terminated prepolymers (E) and (G) using polyol>
The same operation as in (A) was performed except that the type of polyol was the compound shown in Table 1 and the amount added was changed so that the amount of OH groups: the amount of NCO groups was 1:2 and the total amount was 450 g. A prepolymer was obtained.

<Production of isocyanate-terminated prepolymer (B) using polyamine>
A four-necked flask equipped with a stirrer, a thermometer, a dropping funnel and a nitrogen blowing tube was purged with nitrogen, and 67 g of DMEDA and 383 g of MDI were charged into the dropping funnel and the four-necked flask. After that, 50 g of N,N-dimethylformamide was added to the four-necked flask, and polyamine was added dropwise while stirring while maintaining the temperature at 0°C. After the dropwise addition was completed, stirring was continued for 10 minutes to complete the reaction. The resulting prepolymer had a resin concentration of 90%, an NCO content of 3.1% and a viscosity of 43,000 mPa·s/25°C.

<Production of isocyanate-terminated prepolymers (C) and (D) using polyamine>
The same operation as in (B) was performed except that the type of polyamine was the compound shown in Table 1 and the amount added was changed so that the OH group amount: NCO group amount was 1:2 and the total amount was 450 g. A prepolymer was obtained.

<Production of isocyanate-terminated prepolymer (F) using polyamine and polyol>
The polyamine and polyol were the compounds shown in Table 1, and the amount added (OH group amount + amine group amount): NCO group amount was changed to 1:2 and the total amount was 450 g. An isocyanate-terminated prepolymer was obtained by working up.

<Production of blocked (poly)isocyanate compound>
(Production example 1)
The interior of a four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen blowing tube is replaced with nitrogen, and 100 parts by mass of MDI (the number of moles of isocyanate groups in this polyisocyanate is 100), acetic acid n- 92.4 parts by mass of butyl and a blocking agent in an amount corresponding to 105 mol % of the isocyanate groups in the (poly)isocyanate were charged and maintained at 60°C. After that, 0.77 parts by mass of 28% sodium methylate was added and kept for 4 hours. As a result of measuring the infrared spectrum, disappearance of the isocyanate group was confirmed, and then 19.6 parts of n-butanol was added to obtain a composition containing a blocked (poly)isocyanate compound having a solid content concentration of 60% by mass. .

(Production Examples 2 to 13)
A composition containing a blocked (poly)isocyanate compound was prepared in the same manner as in Production Example 1 except that the types and amounts of the (poly)isocyanate and blocking agent were changed as shown in Table 2. Obtained.

(Example 1)
<Production of resin composition>
The blocked (poly)isocyanate compound obtained in Production Example 1 and the primary amines or polyamines listed in Table 4 were added so that the isocyanate group amount/(primary amino group amount + secondary amino group amount) = 0.98. mixed. Thereafter, the solvent was removed with a vacuum pump to reduce the solvent content to 30% by mass or less, thereby obtaining a resin composition.

(Examples 2 to 19)
A resin composition was obtained in the same manner as in Example 1 except that the types of blocked (poly)isocyanate compound and polyamine were changed as shown in Tables 4 to 6.
Tables 4 to 6 show the evaluation results of viscosity, acid resistance, alkali resistance, tensile strength, adhesion strength to concrete, pot life, and storage stability of the resin compositions obtained in Examples.

(Comparative example 1)
When the same operation as in Example 1 was performed except that MDI was used as the unblocked isocyanate compound, the curing reaction proceeded the moment DETDA and MDI were mixed, and a resin composition could not be obtained. , could not be evaluated.

(Comparative example 2)
As shown in Table 7, a resin composition was obtained in the same manner as in Example 1 except that the blocked (poly)isocyanate compound obtained in Production Example 14 was used. Table 7 shows the evaluation results of viscosity, acid resistance, alkali resistance, tensile strength, adhesion strength to concrete, pot life and storage stability of the obtained resin composition.

(Comparative Example 3)
As shown in Table 7, a resin composition was obtained in the same manner as in Example 1, except that a polyamine containing no primary amino group was used. Table 7 shows the results of evaluating the viscosity, acid resistance, alkali resistance, tensile strength, adhesion strength to concrete, pot life, and storage stability of the obtained resin composition.

The resin compositions of the present invention obtained in Examples 1 to 19 had a long pot life, excellent storage stability, and excellent various properties when formed into coating films.

The resin composition obtained in Comparative Example 2 lost fluidity after standing for 12 hours, and the viscosity could not be measured. It had a short pot life, poor storage stability, and poor alkali resistance when used as a coating film.

The resin composition obtained in Comparative Example 3 lost its fluidity after standing still for 12 hours, and the viscosity could not be measured. The pot life was short, the storage stability was poor, and the acid resistance, alkali resistance, tensile strength, and adhesion strength to concrete when made into a coating film were poor.

Claims (8)

containing a blocked (poly)isocyanate compound (a) and a polyamine (b) containing a primary amino group,
The viscosity when left standing at 25° C. for 12 hours is 100 to 5,000,000 mPa s,
A resin composition that cures at 60 to 200°C. The resin composition according to claim 1, wherein the polyamine (b) containing a primary amino group is one or more selected from polyvalent aromatic amines, polyether polyamines, polyethyleneimine, ethyleneamines and aliphatic polyamines. . 3. The resin composition according to claim 1, wherein the isocyanate constituting the blocked (poly)isocyanate compound (a) is an aromatic (poly)isocyanate and/or an aliphatic (poly)isocyanate. The resin composition according to any one of claims 1 to 3, wherein the content of the organic solvent is 30% by mass or less. A polyurea resin obtained by curing the resin composition according to any one of claims 1 to 4. A paint containing the resin composition according to any one of claims 1 to 4. 6. The coating of claim 5, applied by brushing, roller coating or troweling. A coating film comprising the coating material according to claim 6 or 7.