JP6619125B1 - Thermosetting resin composition, coating material for precoat metal, cured product and laminate - Google Patents

Abstract

An object of the present invention is to provide a thermosetting resin composition which can obtain a cured film having excellent durability and appearance at a low temperature and which has excellent storage stability. The thermosetting resin composition of the present invention comprises (A) a resin having a specific hydroxyl group, (B) an alkyletherified melamine resin, and (C) a metal having Pauling's electronegativity of 1.31 to 2.02. A Lewis acid catalyst comprising a cation and a counter anion which is a deprotonated form of a protonic acid having an acid dissociation constant pKa of 1.0 or less, and a solvent (D), wherein the solvent (D) has a Hildebrand solubility parameter value (SP) Value) contains 18.6 to 47.9 of the solvent (D-1), and the content of the solvent (D-1) with respect to the total amount of the solvent (D) is 21% by mass or more, and the solvent (D-1) Among them, the content of the solvent (DS) in which the solubility of the Lewis acid catalyst (C) is 0.01% by mass or more is 4% by mass or more based on the total amount of the solvent (D).

Description

  The present invention relates to a thermosetting resin composition, a cured product composed of the composition, and a laminate including a cured film composed of the composition.

  Moreover, this invention relates to the laminated body containing the coating material for precoat metals, the hardened | cured material which consists of this coating material, and the cured film which consists of this coating material.

  Conventionally, in various fields such as paints for automobiles and paints for home appliances, thermosetting resin compositions containing polyols and alkyl etherified melamines are used, and the storage stability of the compositions is good. In addition, the cured film obtained is required to have excellent durability and appearance. In addition, the curing of the thermosetting resin composition requires a heating time of approximately 10 to 60 minutes at a temperature of approximately 110 to 160 ° C. From the viewpoint of energy saving, the heat can be cured at a lower temperature and in a shorter time. There is a strong demand for curable resins.

  In addition, as a steel plate used for outdoor building materials such as roofs and wall materials, and household appliances such as refrigerators, washing machines, and lighting fixtures, it has been coated before molding and cutting, which is called pre-coated metal. Steel plates are widely used. In various fields such as paints for automobiles and paints for home appliances, a coating material for a pre-coated metal containing a polyol and an alkyl etherified melamine is used, and the storage stability of the coating material is good. The cured film to be obtained is required to have excellent durability and appearance.

  In general, pre-coated metal is coated in a continuous line, and only about 10 to 120 seconds of drying time can be secured for its curing, but the peak metal temperature (PMT), which is the maximum temperature of the metal to be coated, is 150 to 260 ° C. Since the temperature of the drying furnace may reach 300 ° C., there is a strong demand for a thermosetting resin that can be cured in a shorter time, particularly from the viewpoint of energy saving.

Here, in the crosslinking reaction between the polyol and the alkyl etherified melamine, the ether exchange proceeds between the hydroxyl group (A- OH ) of the polyol and the ether group (B- OR ) of the alkyl etherified melamine, and the alkyl etherified melamine The derived alcohol (R—OH) is eliminated. Although this reaction is an equilibrium reaction, crosslinking can be irreversibly caused by volatilizing the desorbed alcohol out of the system, and as a condition for this, a temperature of approximately 110-160 ° C. and heating for 10-60 minutes Time is needed. In this crosslinking reaction, a catalyst may be used for the purpose of promoting crosslinking, and it has been reported that a Lewis acid catalyst is effective in addition to a protonic acid.

  For example, in Patent Document 1, various Lewis acids can be applied when a polyol having a specific range of epoxy equivalent, hydroxyl value, glass transition temperature and weight average molecular weight is cured with an isocyanate containing an amino resin or a block. It is disclosed that particularly preferred catalysts are zinc catalysts such as zinc chloride, zinc naphthenate, zinc octylate and the like.

  Patent Document 2 discloses that a polyester resin and a melamine are used by using a catalyst selected from a specific Lewis acid catalyst and a perfluoroacetic acid catalyst under baking conditions of 280 to 450 ° F. (138 to 232 ° C.) for 5 to 60 seconds. When the crosslinking reaction of the crosslinking agent and epoxy resin is promoted, and when a low boiling point solvent such as an aromatic compound, ester or ketone solvent or a mixture of aromatic ester or ketone solvent is required for rapid solvent evaporation It is stated to be advantageous. However, as a result of the verification by the present inventors, when a test was conducted with reference to these examples, good results were not obtained.

  As the alkyl etherified melamine, industrially, methyl etherified melamine (hereinafter referred to as “methylated melamine”) and butyl etherified melamine (hereinafter referred to as “butylated melamine”) are produced and used. However, in Patent Document 3, baking is performed at 90 to 180 ° C. for 20 to 30 minutes (more specifically at 120 ° C. for 30 minutes) using an ethyl etherified melamine (hereinafter referred to as “ethylated melamine”) resin. It is disclosed that a cured film having a better balance between hardness and water resistance can be formed by curing a polyol under no conditions under conditions than when methylated melamine and butylated melamine are used.

  Furthermore, in Patent Document 4, in the reaction of an acrylic polyol having a hydroxyl value of 80 to 110 mgKOH / g and a weight average molecular weight of 10,000 to 100,000 with an alkyl etherified melamine, an alkyl phosphate is used as a catalyst, and 80 to 120 ° C. (more specifically) In particular, it is disclosed that a cured film having certain physical properties can be formed by heating at 80 ° C. for 30 minutes. In Patent Document 4, unlike Patent Document 3, it is not shown that ethylated melamine is preferable to methylated melamine and butylated melamine, and in Examples, a coating formed with ethylated melamine or butylated melamine is not shown. There is no difference in the physical properties of the film. Patent Document 4 shows that performance is not sufficiently exhibited when an acrylic polyol having a hydroxyl value of 60 mgKOH / g is used.

  Patent Document 5 discloses a coating film for an outer plate containing a specific alkoxysilane, at least one of a partially hydrolyzable condensate of an organosilicon compound, and a film-forming resin.

  Patent Document 6 discloses a compound having a carboxyl group blocked with a specific vinyl (thio) ether group or a heterocyclic group having a vinyl type double bond having an oxygen atom or a sulfur atom as a hetero atom (polyol). A compound having a reactive functional group capable of forming a chemical bond with the blocked carboxyl group (including melamine resin), a compound containing an epoxy group, a specific sulfur-containing compound and a specific Lewis A thermosetting composition containing a heat-latent acid catalyst containing an acid, or a reaction capable of forming a chemical bond with the blocked carboxyl group in one molecule and the blocked carboxyl group by heating. A thermosetting composition containing a self-crosslinking compound having a functional functional group is disclosed.

JP-A-8-176465 JP-T-2004-518788 JP 2014-098105 A JP 2017-071666 A JP-A-10-130581 Japanese Patent Laying-Open No. 2005-036236

  The present invention provides a thermosetting resin composition that can obtain a cured film excellent in durability and appearance at a low temperature and has excellent storage stability, and a method for producing a cured film comprising the composition. For the purpose.

  In addition, the present invention can provide a cured film excellent in durability and appearance in a short heating time, and has excellent storage stability, and a method for producing a cured film comprising the coating material The purpose is to provide.

  The inventors of the present invention have studied a catalyst and a solvent regarding a thermosetting resin composition containing a polyol and an alkyl etherified melamine and a coating material for a pre-coated metal. Lewis acid having a metal center, particularly a counter anion generated by deprotonation of a cation composed of a metal element having a Pauling electronegativity of 1.31 to 2.02 and a proton acid having an acid dissociation constant pKa of 1.0 or less It has been found that the use of a Lewis acid catalyst comprising the following has a high effect of promoting the reaction at low temperature and the effect of promoting the reaction in a short time.

  The reason why such a high effect is obtained is that the Lewis acid catalyst has a central component of a metal element whose electronegativity is too low when interacting with oxygen and nitrogen atoms contained in polyols and alkyl etherified melamines. When an acid is used, although the interaction is strong, the polarization is too large and the solubility in polyols, alkyl etherified melamines, and solvents tends to be poor. Conversely, if the electronegativity of the central metal is too high, the interaction is weak. This is considered to be because the activation effect tends to be inferior. Further, the reason why the counter anion having a pKa of 1.0 or less is good is that they are stable as anions, and the electron density of the Lewis acid center can be kept low. It is presumed that this interaction is strengthened and thereby functions effectively as a catalyst.

  Therefore, the present inventors further investigated the influence of the solubility of the Lewis acid catalyst in the solvent. As a result, the solvent having a solubility of the Lewis acid catalyst of 0.01% by mass or more was more than a certain amount with respect to the whole solvent. It has been found that if it is not contained in an amount, the above-mentioned reaction promoting effect is limited.

  Based on these findings, the inventors have completed the present invention. That is, the present invention includes the following aspects.

[1] (A) Resin having a hydroxyl group with a solid hydroxyl value of 25 to 300 mg KOH / g (excluding the alkyl etherified melamine resin (B)), (B) alkyl etherified melamine resin, C) a Lewis acid catalyst comprising a cation composed of a metal having a Pauling electronegativity of 1.31 to 2.02 and a counter anion which is a deprotonated proton acid having an acid dissociation constant pKa of 1.0 or less, And (D) a solvent,
The solvent (D) includes a solvent (D-1) having a Hildebrand solubility parameter value (SP value) of 18.6 to 47.9, and the solvent (D-1) relative to the total amount of the solvent (D) The content of is 21% by mass or more,
Among the said solvent (D-1), content of the solvent (DS) whose solubility of the said Lewis' acid catalyst (C) is 0.01 mass% or more is 4 with respect to the whole quantity of the said solvent (D). A thermosetting resin composition characterized by being at least mass%.

  [2] The thermosetting resin composition according to item [1], wherein the Lewis acid catalyst (C) is at least one selected from the group consisting of nitrates, sulfates and halides.

  [3] The item according to [1] or [2], wherein the cation constituting the Lewis acid catalyst (C) comprises at least one metal selected from the group consisting of magnesium, aluminum and nickel. Thermosetting resin composition.

  [4] The thermosetting according to any one of items [1] to [3], wherein the solvent (D-1) is at least one selected from the group consisting of alcohol and water. Resin composition.

  [5] The resin (A) having a hydroxyl group is at least one resin selected from the group consisting of an acrylic resin having a hydroxyl group, a polyester resin having a hydroxyl group, an epoxy resin having a hydroxyl group, and a urethane resin having a hydroxyl group. The thermosetting resin composition according to any one of Items [1] to [4].

  [6] The item wherein the resin (A) having a hydroxyl group is at least one resin selected from the group consisting of an acrylic resin having a hydroxyl group, a polyester resin having a hydroxyl group, and a urethane resin having a hydroxyl group. The thermosetting resin composition according to any one of [1] to [4].

  [7] (E) From the group consisting of pigments, dyes, leveling agents, stability improvers, foam inhibitors, weather resistance improvers, anti-waxing agents, antioxidants, dispersants, wetting agents, thixotropic agents and ultraviolet absorbers The thermosetting resin composition according to any one of Items [1] to [6], further comprising at least one additive selected.

  [8] The mass ratio (A / B) of the solid content of the resin (A) having a hydroxyl group and the solid content of the alkyl etherified melamine resin (B) is 95/5 to 45/55, The thermosetting resin composition according to any one of Items [1] to [7].

  [9] The content of the Lewis acid catalyst (C) is 0.01 to 5 mass with respect to a total of 100 mass parts of the solid content of the resin (A) having a hydroxyl group and the alkyl etherified melamine resin (B). The thermosetting resin composition according to any one of Items [1] to [8], which is within a range of parts.

  [10] A cured product comprising the thermosetting resin composition according to any one of items [1] to [9].

  [11] Manufacture of hardened | cured material characterized by including the process of heating and hardening the thermosetting resin composition as described in any one of claim | item [1]-[9] to the temperature of 60-125 degreeC. Method.

  [12] The method for producing a cured product according to item [11], wherein the heating time in the step is in the range of 10 seconds to 60 minutes.

  [13] A laminate comprising a cured film comprising the thermosetting resin composition according to any one of items [1] to [9].

  [14] A method for producing a laminate including a covering and a cured film, the coating being obtained by applying the thermosetting resin composition according to any one of Items [1] to [9] to the covering. The manufacturing method of the laminated body characterized by including the process of forming, and the process of heating the said coating film at the temperature of 60-125 degreeC, and forming a cured film.

  [15] The method for producing a laminate according to item [14], wherein the covering is a metal or a resin.

[16] (A) Resin having a hydroxyl group with a solid hydroxyl value of 25 to 300 mg KOH / g (excluding alkyl etherified melamine resin (B)), (B) alkyl etherified melamine resin, C) a Lewis acid catalyst comprising a cation composed of a metal having a Pauling electronegativity of 1.31 to 2.02 and a counter anion which is a deprotonated proton acid having an acid dissociation constant pKa of 1.0 or less, (D) Solvent, and (E) From pigments, dyes, leveling agents, stability improvers, foam inhibitors, weather resistance improvers, anti-waxing agents, antioxidants, dispersants, wetting agents, thixotropic agents and UV absorbers At least one additive selected from the group consisting of:
The solvent (D) includes a solvent (D-1) having a Hildebrand solubility parameter value (SP value) of 18.6 to 47.9, and the solvent (D-1) relative to the total amount of the solvent (D) The content of is 21% by mass or more,
Among the said solvent (D-1), content of the solvent (DS) whose solubility of the said Lewis' acid catalyst (C) is 0.01 mass% or more is 4 with respect to the whole quantity of the said solvent (D). Mass% or more,
Content of the said additive (E) is 10 to 300 mass parts with respect to a total of 100 mass parts of the said resin (A) and resin (B), The coating material for precoat metals characterized by the above-mentioned .

  [17] The coating material for precoated metals according to item [16], wherein the Lewis acid catalyst (C) is at least one selected from the group consisting of nitrates, sulfates and halides.

  [18] The item [16] or [17], wherein the cation constituting the Lewis acid catalyst (C) comprises at least one metal selected from the group consisting of magnesium, aluminum and nickel. Pre-coated metal coating material.

  [19] The precoat metal according to any one of items [16] to [18], wherein the solvent (D-1) is at least one selected from the group consisting of alcohol and water. Coat material.

  [20] The hydroxyl group-containing resin (A) is at least one resin selected from the group consisting of a hydroxyl group-containing acrylic resin, a hydroxyl group-containing polyester resin, a hydroxyl group-containing epoxy resin, and a hydroxyl group-containing urethane resin. The coating material for precoated metal according to any one of items [16] to [19], wherein:

  [21] The item wherein the hydroxyl group-containing resin (A) is at least one resin selected from the group consisting of a hydroxyl group-containing acrylic resin, a hydroxyl group-containing polyester resin, and a hydroxyl group-containing urethane resin. 16]-[19] The coating material for pre-coated metals according to any one of [19].

  [22] The mass ratio (A / B) of the solid content of the resin (A) having a hydroxyl group and the solid content of the alkyl etherified melamine resin (B) is 95/5 to 45/55, The coating material for precoat metal according to any one of items [16] to [21].

  [23] The content of the Lewis acid catalyst (C) is 0.01 to 5 masses with respect to a total of 100 mass parts of the solid content of the hydroxyl group-containing resin (A) and the alkyl etherified melamine resin (B). The coating material for a precoat metal according to any one of Items [15] to [22], wherein the coating material is a part range.

  [24] A cured product comprising the coating material for a precoat metal according to any one of items [16] to [23].

  [25] A step of heating and curing the precoat metal coating material according to any one of items [16] to [23] under conditions of a peak metal temperature of 120 ° C. or more and 250 ° C. or less and 5 seconds or less. A method for producing a cured product.

  [26] A laminate comprising a cured film comprising the coating material for a precoat metal according to any one of items [16] to [23].

  [27] A method for producing a laminate including a covering and a cured film, wherein the coating material is applied by applying the precoat metal coating material according to any one of items [16] to [23] to the covering. The manufacturing method of the laminated body characterized by including the process of forming, and the process of forming the cured film by heating the said coating film on the conditions whose peak metal temperature is 120 degreeC or more and 250 degrees C or less and 5 seconds or less.

  [28] The method for producing a laminate according to item [27], wherein the covering is a metal or a resin.

  According to the present invention, a cured film excellent in durability and appearance can be obtained at a low temperature, and the storage stability is better than a conventional low-temperature curable isocyanate resin composition, and the hardness is high. A thermosetting resin composition capable of forming a coating film and a method for producing a cured product comprising the composition are provided. In addition, the realization of low-temperature curing has made it possible not only to save energy in conventional systems, but also to paint on plastics with low heat resistance.

  According to the present invention, a cured film excellent in durability and appearance can be obtained in a short heating time, and the storage stability is better than that of a conventional thermosetting isocyanate resin composition. There are provided a coating material for pre-coated metal capable of forming a coating film having high hardness, and a method for producing a cured product comprising the coating material.

  Hereinafter, the present invention will be described in detail.

[Thermosetting resin composition]
The thermosetting resin composition of the present invention (hereinafter also simply referred to as “the composition of the present invention”) is a resin having a hydroxyl group (A) having a hydroxyl value of 25 to 300 mgKOH / g of a solid content (however, The alkyl etherified melamine resin (B) is excluded), (B) an alkyl etherified melamine resin, (C) a cation made of a metal having Pauling's electronegativity of 1.31 to 2.02, and an acid dissociation constant pKa. A Lewis acid catalyst comprising a counter anion which is a deprotonated form of a protonic acid of 1.0 or less, and (D) a solvent, and may further contain an additive (E) as necessary.

In the composition of the present invention, the solvent (D) includes a solvent (D-1) having a Hildebrand solubility parameter value (SP value) of 18.6 to 47.9, and is based on the total amount of the solvent (D). The content of the solvent (D-1) is 21% by mass or more,
Among the said solvent (D-1), content of the solvent (DS) whose solubility of the said Lewis' acid catalyst (C) is 0.01 mass% or more is 4 with respect to the whole quantity of the said solvent (D). It is at least mass%.

<Resin having hydroxyl group (A)>
The resin (A) having a hydroxyl group (hereinafter also simply referred to as “resin (A)”) used in the present invention has a solid hydroxyl value of 25 to 300 mgKOH / g and an alkyl ether described later. Although it will not specifically limit if it is resin other than the chlorinated melamine resin (B), For example, the acrylic resin which has a hydroxyl group, the polyester resin which has a hydroxyl group, the epoxy resin which has a hydroxyl group, the urethane resin which has a hydroxyl group etc. are mentioned. Among these, an acrylic resin having a hydroxyl group, a polyester resin having a hydroxyl group, and a urethane resin having a hydroxyl group are preferable, and an acrylic resin having a hydroxyl group and a polyester resin having a hydroxyl group are more preferable. The said resin (A) may be used individually by 1 type, and may use 2 or more types.

  The hydroxyl value of the resin (A) is preferably 30 to 250 mgKOH / g, more preferably 40 to 200 mgKOH / g (solid content). When the hydroxyl value is within the above range, the cross-linking density of the coating film is high and the strength and hardness of the coating film are sufficient, the flexibility of the coating film is appropriate, and the impact resistance and appearance are good.

  The resin (A) has a polystyrene equivalent weight average molecular weight (Mw) measured by GPC of usually 5,000 to 200,000, preferably 10,000 to 100,000, more preferably 20,000. ~ 80,000. When the Mw of the resin (A) is within the above range, the paintability, the appearance of the coating film, the strength, the hardness, and the wear resistance are excellent.

  Examples of commercially available resins (A) include “Cotax LH-601”, “Cotax LH-591” manufactured by Toray Fine Chemical Co., Ltd., “Almatex 646” manufactured by Mitsui Chemicals, Inc. Tex 646SB "," Olestar Q810 "," Olestar Q519 "and the like.

  The content ratio of the resin (A) (solid content) with respect to the total amount of the composition of the present invention is preferably 1 to 60% by mass, more preferably 1.1 to 57.0% by mass, and still more preferably 5.0 to 40%. 0.0% by mass. When the content ratio of the resin (A) is within the above range, the coating property, the storage stability, the strength, hardness, and abrasion resistance of the coating film are excellent.

<Alkyl etherified melamine resin (B)>
The alkyl etherified melamine resin (B) used in the present invention (hereinafter also simply referred to as “melamine resin (B)”) is a melamine resin (the melamine resin is a thermosetting resin obtained from melamine and formaldehyde). A resin in which at least a part of the methylol group is alkyl etherified.

  Preferable examples of the melamine resin (B) include ethylated (ethyl etherified) melamine resins described in Patent Document 3.

  In addition, as commercial products of the melamine resin (B), “Uban 20SE60”, “Uban 28-60” manufactured by Mitsui Chemicals, Inc., “Cymel 327”, “Cymel 370” series manufactured by Daicel Ornex, etc. are used. be able to.

  The melamine resin (B) has a polystyrene-equivalent weight average molecular weight measured by GPC (gel permeation chromatography) of preferably 800 to 15000, more preferably 1000 to 7000, still more preferably 1100 to 5000. is there. When the weight average molecular weight of the melamine resin (B) is in the above range, a resin composition having an appropriate viscosity can be obtained, and a cured product having excellent mechanical properties, smoothness, appearance, and the like can be obtained.

  The melamine resin (B) is preferably obtained by condensing melamine, formaldehyde, and an alcohol having an alkyl chain having 1 to 6 carbon atoms in the presence of an acid catalyst. As a method for producing such a melamine resin (B), the method described in Patent Document 3 can be used. For example, in the case of an ethylated melamine resin, ethanol is used as the alcohol. As the ethanol, hydrous ethanol may be used, or so-called mixed ethanol containing a small amount of methanol, isopropanol, or the like may be used. .

  The melamine is not particularly limited and may be synthesized by a conventionally known method or may be a commercially available product.

  The formaldehyde may be an aqueous solution or solid paraformaldehyde. Paraformaldehyde having a formalin concentration of 80% or more is preferred from the economical viewpoint.

  The content ratio of the melamine resin (B) (solid content) with respect to the total amount of the composition of the present invention is preferably 0.1 to 40% by mass, more preferably 0.12 to 33.0% by mass, and still more preferably 3 to 3%. 25% by mass. When the content ratio of the melamine resin (B) is within the above range, a coating film having an excellent balance between hardness and flexibility can be obtained.

  The mass ratio (A / B) of the solid content of the resin (A) and the solid content of the melamine resin (B) is preferably 95/5 to 45/55, more preferably 85/15 to 65/35. It is. When the mass ratio (A / B) is in the above range, a coating film having an excellent balance between hardness and flexibility can be obtained.

<Lewis acid catalyst (C)>
The Lewis acid catalyst (C) used in the present invention is a deprotonated product of a cation composed of a metal having a Pauling electronegativity of 1.31 to 2.02 and a protonic acid having an acid dissociation constant pKa of 1.0 or less. And a counter anion.

  Examples of metals having Pauling's electronegativity of 1.31 to 2.02 include magnesium, manganese, aluminum, cobalt, nickel, tin, zinc, copper, and bismuth. Among these, magnesium, aluminum, and nickel are preferable from the viewpoint of a high curing rate. When the resin (A) is an aqueous dispersion, the Lewis acid catalyst (C) made of an inorganic salt may act as an aggregating agent, but nickel, copper, and cobalt are less likely to aggregate the resin (A). Is preferable.

  Examples of the protonic acid (Bronsted acid) having an acid dissociation constant pKa of 1.0 or less include nitric acid, sulfuric acid, hydrochloric acid, hydrobromic acid and the like. The acid dissociation constant is a value when water is used as a solvent.

  The Lewis acid catalyst (C) is preferably at least one selected from the group consisting of nitrates, sulfates and halides, more preferably nitrates or halides, and even more preferably nitrates.

  Specific examples of the Lewis acid catalyst (C) include magnesium nitrate, manganese nitrate, aluminum nitrate, zinc nitrate, cobalt nitrate, copper nitrate, nickel nitrate, nickel sulfate, and bismuth chloride.

  The content of the Lewis acid catalyst (C) is preferably 0.01 to 5 mass with respect to 100 mass parts in total of the solid content of the resin (A) having a hydroxyl group and the alkyl etherified melamine resin (B). Part, more preferably 0.1 to 4 parts by weight. When the content of the Lewis acid catalyst (C) is within the above range, a thermosetting resin composition having excellent storage stability and low temperature curability can be obtained.

<Solvent (D)>
The solvent (D) used in the present invention includes a solvent (D-1) having a Hildebrand solubility parameter value (SP value) of 18.6 to 47.9. Content of the said solvent (D-1) with respect to the whole quantity of the said solvent (D) is 21 mass% or more, Preferably it is 30-99 mass%.

  Moreover, content of the solvent (DS) whose solubility of the said Lewis' acid catalyst (C) is 0.01 mass% or more among the said solvent (D-1) is with respect to the whole quantity of the said solvent (D). 4 mass% or more, preferably 10 to 95 mass%.

  Examples of the solvent (D-1) include alcohol, water, and tetrahydrofuran. Of these, alcohol and water are preferred. The solvent (D-1) may be used alone or in combination of two or more. Examples of the alcohol include methanol, ethanol, iso-propanol, iso-butanol, n-butanol, sec-butanol and the like.

  The solvent (DS) varies depending on the type of the Lewis acid catalyst (C). For example, as shown in Table 1-1 and Table 1-2 (hereinafter collectively referred to as “Table 1”, and the other tables are also referred to in the same manner), the Lewis acid catalyst (C) is nickel sulfate. (II) In the case of hexahydrate, water corresponds to the solvent (DS), but methanol, ethanol, iso-propanol, iso-butanol, n-butanol, sec-butanol and tetrahydrofuran are solvents (DS). Does not fall under). When the Lewis acid catalyst (C) is magnesium nitrate hexahydrate, water, methanol, ethanol, iso-propanol, iso-butanol, n-butanol, sec-butanol and tetrahydrofuran are all solvents (D- S).

  The solvent (D) may contain a solvent (D-2) other than the solvent (D-1). Examples of the solvent (D-2) include, but are not limited to, alkylbenzene solvents such as benzene, toluene, and xylene, and acetate solvents such as ethyl acetate, propyl acetate, butyl acetate, amyl acetate, and methyl acetoacetate. Examples thereof include ketone solvents such as dioxane, acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone.

  The total content of the solvent (D) with respect to the total amount of the composition of the present invention is preferably 30 to 95% by mass, more preferably 40.0 to 90.0% by mass, and even more preferably 50.0 to 80.0% by mass. %.

<Additive (E)>
The composition of this invention may contain an additive (E) as needed. Such an additive (E) is not particularly limited as long as the effects of the present invention are not impaired, and known additives (for example, additives described in Patent Documents 1 to 4) can be used. Specific examples include pigments, dyes, leveling agents, stability improvers, foam inhibitors, weather resistance improvers, anti-waxing agents, antioxidants, dispersants, wetting agents, thixotropic agents, and ultraviolet absorbers. An additive (E) may be used individually by 1 type, or may use 2 or more types.

  The content of the additive (E) with respect to the total amount of the composition of the present invention is preferably 0 to 30% by mass.

  The total amount of the resin (A), the melamine resin (B), the Lewis acid catalyst (C), and the additive (E) is preferably 10 to 60% by mass with respect to the total amount of the composition of the present invention. More preferably, it is 20-50 mass%. When the total content of components (A), (B), (C) and (E) is within the above range, a thermosetting resin composition having excellent paintability, coating film properties and storage stability is obtained. It is done.

<Hardened product and laminate>
The first aspect of the cured product of the present invention (hereinafter also referred to as “first cured product”) is characterized by comprising the composition of the present invention and is usually in the form of a cured film. The first aspect of the laminate of the present invention (hereinafter also referred to as “first laminate”) includes a cured film made of the composition of the present invention.

  The manufacturing method of the 1st hardened | cured material (cured film) of this invention heats and cures the composition of this invention to the temperature of 60-125 degreeC, Preferably it is 60-120 degreeC, More preferably, it is 60-90 degreeC. Process (hereinafter also referred to as “heating process (1)”). Thus, since the composition of the present invention can be cured at a low temperature, that is, the time from the start of heating until reaching the curing temperature can be shortened, the method of the present invention is excellent in productivity.

  The heating time in the heating step (1) is preferably 10 seconds to 60 minutes, more preferably 30 seconds to 60 minutes, still more preferably 1 to 60 minutes, even more preferably 1 to 40 minutes, and particularly preferably 5 to 5 minutes. 30 minutes. Thus, since the composition of the present invention can be cured in a short heating time, the method of the present invention is excellent in productivity. Note that heating may be performed in two or more stages. Furthermore, the heating step (1) may be performed under reduced pressure or in an inert gas atmosphere.

  The composition of the present invention can be suitably used for paint (coating material) applications. That is, by applying the composition of the present invention to a covering to form a coating film, the coating film is heated (dried) under the same conditions as in the heating step (1) to form a cured film, The 1st laminated body of this invention can be manufactured.

  Examples of the covering (base material) include metal materials such as iron, aluminum, zinc, stainless steel and those subjected to surface treatment, vinyl chloride, polyethylene terephthalate, polyethylene, polypropylene, polycarbonate, ABS, and surfaces thereof. Examples thereof include resin materials such as those that have been treated. In addition, those coated with a primer, an intermediate coat, and a top coat can be used as necessary.

  As described above, since the present invention can be cured at a low temperature in a short time, thermal deformation of the covering can be suppressed. That is, in this invention, since the coating body inferior to heat resistance can be used, various coating bodies can be selected according to a desired use.

  The method of applying the composition of the present invention to the covering is not particularly limited, and a spray coating method, a dip coating method, a roll coating method, a gravure coating method, a spin coating method, and a bar coater or a doctor blade are used. The method etc. are mentioned.

  The thickness of the cured film is not particularly limited, and may be appropriately selected according to a desired application, but is preferably 5 to 50 μm, more preferably 10 to 20 μm.

[Coating material for pre-coated metal]
The coating material for precoat metal of the present invention (hereinafter also simply referred to as “coating material of the present invention”) is a resin having a hydroxyl group (however, alkyl ether having a hydroxyl value of 25 to 300 mg KOH / g in solid content). (B) alkyl etherified melamine resin, (C) a cation made of a metal having Pauling's electronegativity of 1.31 to 2.02, and an acid dissociation constant pKa of 1. A Lewis acid catalyst comprising a counter anion which is a deprotonated form of a protonic acid of 0 or less, (D) a solvent, and (E) a pigment, a dye, a leveling agent, a stability improver, a foam inhibitor, a weather resistance improver, It contains at least one additive selected from the group consisting of anti-waxing agents, antioxidants, dispersants, wetting agents, thixotropic agents and ultraviolet absorbers.

In the coating material of the present invention, the solvent (D) includes a solvent (D-1) having a Hildebrand solubility parameter value (SP value) of 18.6 to 47.9, and is based on the total amount of the solvent (D). The content of the solvent (D-1) is 21% by mass or more,
Among the said solvent (D-1), content of the solvent (DS) whose solubility of the said Lewis' acid catalyst (C) is 0.01 mass% or more is 4 with respect to the whole quantity of the said solvent (D). Mass% or more,
Content of the said additive (E) is 10 mass parts or more and 300 mass parts or less with respect to a total of 100 mass parts of the said resin (A) and resin (B).

  The details of the components (A) to (E) constituting the coating material of the present invention are the resin (A), melamine resin (B), and Lewis acid catalyst in the composition of the present invention described above, except as described below. (C), solvent (D) and additive (E) are as described.

  The content ratio of the resin (A) (solid content) with respect to the total amount of the coating material of the present invention is preferably 1 to 60% by mass, more preferably 1.11 to 51.8% by mass, and still more preferably 5.0 to 40%. 0.0% by mass. When the content ratio of the resin (A) is within the above range, the coating property, the storage stability, the strength, hardness, and abrasion resistance of the coating film are excellent.

  The content ratio of the melamine resin (B) (solid content) with respect to the total amount of the coating material of the present invention is preferably 0.1 to 40% by mass, more preferably 0.12 to 30.0% by mass, and still more preferably 3. It is 0-25.0 mass%. When the content ratio of the melamine resin (B) is within the above range, a coating film having an excellent balance between hardness and flexibility can be obtained.

  The mass ratio (A / B) of the solid content of the resin (A) and the solid content of the melamine resin (B) is preferably 95/5 to 45/55, more preferably 85/15 to 65/35. It is. When the mass ratio (A / B) is in the above range, a coating film having an excellent balance between hardness and flexibility can be obtained.

  The content of the Lewis acid catalyst (C) is preferably 0.01 to 5 mass with respect to 100 mass parts in total of the solid content of the resin (A) having a hydroxyl group and the alkyl etherified melamine resin (B). Part, more preferably 0.1 to 4 parts by weight. When the content of the Lewis acid catalyst (C) is within the above range, a precoat metal coating material excellent in storage stability and short-time curability can be obtained.

  The total content of the solvent (D) with respect to the total amount of the coating material of the present invention is preferably 30 to 95% by mass, more preferably 40.0 to 90.0% by mass, and even more preferably 50.0 to 80.0% by mass. %.

  The content of the additive (E) in the coating material of the present invention is 10 parts by mass or more and 300 parts by mass or less, preferably 50 parts by mass with respect to 100 parts by mass in total of the resin (A) and the resin (B). The amount is 250 parts by mass or less.

  The total amount of the resin (A), the melamine resin (B), the Lewis acid catalyst (C) and the additive (E) is preferably 10 to 60% by mass, based on the total amount of the coating material of the present invention. More preferably, it is 20-50 mass%. When the total content of components (A), (B), and (E) is within the above range, a precoat metal coating material having excellent paintability, coating film physical properties, and storage stability can be obtained.

<Hardened product and laminate>
The second aspect of the cured product of the present invention (hereinafter also referred to as “second cured product”) is characterized by comprising the coating material of the present invention, and is usually in the form of a cured film. The second aspect of the laminate of the present invention (hereinafter also referred to as “second laminate”) includes a cured film made of the coating material of the present invention.

  In the method for producing the second cured product (cured film) of the present invention, the coating material of the present invention is subjected to a peak metal temperature of 120 ° C. to 250 ° C. and 5 seconds or less, preferably a peak metal temperature of 130 ° C. to 180 ° C. And a step of heating and curing under conditions of 0.5 seconds to 5 seconds (hereinafter also referred to as “heating step (2)”). The peak metal temperature refers to the temperature at which the surface temperature of the metal to which the coating material is applied reaches. Thus, since the coating material of the present invention can be cured in a short heating time, the method of the present invention is excellent in productivity. Note that heating may be performed in two or more stages. Furthermore, the heating step (2) may be performed under reduced pressure or in an inert gas atmosphere.

  The coating material of the present invention can be suitably used for paint (coating material) applications. That is, by applying the coating material of the present invention to a covering to form a coating film, the coating film is heated (dried) under the same conditions as in the heating step (2) to form a cured film, The 2nd laminated body of this invention can be manufactured.

  Examples of the covering (base material) include metal materials such as iron, aluminum, zinc, stainless steel, and those subjected to surface treatment. In addition, those coated with a primer, an intermediate coat, and a top coat can be used as necessary.

  As described above, in the present invention, since it can be cured in a short time, thermal deformation of the covering can be suppressed.

A method for applying the coating material of the present invention to the covering is not particularly limited, and a spray coating method, a dip coating method, a roll coating method, a gravure coating method, a spin coating method, and a bar coater or a doctor blade are used. Methods, etc.
The thickness of the cured film is not particularly limited, and may be appropriately selected according to a desired application, but is preferably 5 to 50 μm, more preferably 10 to 20 μm.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example, this invention is not limited to these Examples at all.

[material]
In the following Examples and Comparative Examples, the raw materials used in preparing the composition (coating material) and the coating material and the covering (base material) used in applying the composition are as follows.

<Resin having hydroxyl group (A)>
≪Polyester resin having hydroxyl group≫
・ (A-1) "Almatex P646" manufactured by Mitsui Chemicals, Inc.
Solvent: Solvesso # 100 (manufactured by ExxonMobil Chemical Co., SP value = 18.0) / Methyl isobutyl ketone (SP value = 17.2) = 9/1 mixed solvent Solid content: 60%
Weight average molecular weight: 51,000 Hydroxyl value: 52 mgKOH / g
・ (A-2) "Almatex P646SB" manufactured by Mitsui Chemicals, Inc.
Solvent: sec-butanol (SP value = 22.1)
Solid content: 60%
Weight average molecular weight: 51,000 Hydroxyl value: 52 mgKOH / g
≪Acrylic resin with hydroxyl group≫
・ (A-3) "Cotax LH-591" manufactured by Toray Fine Chemical Co., Ltd.
Solvent: n-butyl acetate (SP value = 17.4)
Solid content: 55%
Hydroxyl value: 31 mgKOH / g
・ (A-4) "Olestar Q810" manufactured by Mitsui Chemicals, Inc.
Solvent: n-butyl acetate (SP value = 17.4)
Solid content: 52%
Weight average molecular weight: 35,000 Hydroxyl value: 50 mgKOH / g
-(A-5) "Olestar Q519" manufactured by Mitsui Chemicals, Inc.
Solvent: Mixed solvent of n-butyl acetate (SP value = 17.4) and methyl isobutyl ketone (SP value = 17.2) Solid content: 50%
Hydroxyl value: 151 mgKOH / g
・ (A-6) "Olestar Q203" manufactured by Mitsui Chemicals, Inc.
Solvent: Solvesso # 100 (manufactured by ExxonMobil Chemical Co., SP value = 18.0) and methyl isobutyl ketone (SP value = 17.2) Solid solvent: 60%
Hydroxyl value: 97 mgKOH / g
≪Titanium oxide dispersed polyol liquid A1≫
Paint conditioner (made by RED DEVIL, 1400-0H), 100 parts by mass of titanium oxide (manufactured by Ishihara Sangyo Co., Ltd., CR-93) as additive (E), 116.7 parts by mass of polyester resin (A-1) having a hydroxyl group Then, 25 parts by mass of Solvesso # 100 (manufactured by ExxonMobil Chemical Co., SP value = 18.0) was added as a solvent, and 130 parts by mass of glass beads (manufactured by Sekiya Rika Co., Ltd., 2 mm diameter) were added and stirred for 5 hours. After stirring, the glass beads were filtered through a mesh to obtain a titanium oxide-dispersed polyol liquid A1.

≪Titanium oxide dispersed polyol liquid A1′≫
Paint conditioner (made by RED DEVIL, 1400-0H), titanium oxide (Ishihara Sangyo, CR-93) as additive (E), hydroxyl group-containing polyester resin (A-1), and solvent as Solvesso # 100 ( Exxon Mobil Chemical Co., Ltd., SP value = 18.0) is added to the amounts shown in Tables 10 to 13 (the values in the table are parts by mass), and further glass beads (Sekiya Rika Co., Ltd., 2 mm diameter). 200 parts by mass was added and stirred for 5 hours. After stirring, the glass beads were filtered through a mesh to obtain a titanium oxide-dispersed polyol liquid A1 ′.

≪Titanium oxide dispersed polyol liquid A2≫
Paint conditioner (made by RED DEVIL, 1400-0H), titanium oxide (Ishihara Sangyo, CR-93) as additive (E), polyester resin (A-2) having a hydroxyl group, and Solvesso # 100 (as a solvent) ExxonMobil Chemical Co., SP value = 18.0) is added to the amount shown in Table 11 (the numerical values in the table are parts by mass), and further glass beads (Sekiya Rika Co., Ltd., 2 mm diameter) 200 mass A portion was added and stirred for 5 hours. After stirring, the glass beads were filtered through a mesh to obtain a titanium oxide-dispersed polyol liquid A2.

≪Titanium oxide dispersed polyol liquid A4≫
Paint conditioner (made by RED DEVIL, 1400-0H), titanium oxide (Ishihara Sangyo, CR-93) as additive (E), polyester resin (A-4) having a hydroxyl group, and Solvesso # 100 (as a solvent) ExxonMobil Chemical Co., SP value = 18.0) is added to the amount shown in Table 11 (the numerical values in the table are parts by mass), and further glass beads (Sekiya Rika Co., Ltd., 2 mm diameter) 200 mass A portion was added and stirred for 5 hours. After stirring, the glass beads were filtered through a mesh to obtain a titanium oxide-dispersed polyol liquid A4.

≪Titanium oxide dispersed polyol liquid A6≫
Paint conditioner (made by RED DEVIL, 1400-0H), titanium oxide (Ishihara Sangyo, CR-93) as additive (E), polyester resin (A-6) having a hydroxyl group, and Solvesso # 100 (as a solvent) ExxonMobil Chemical Co., SP value = 18.0) is added to the amount shown in Table 11 (the numerical values in the table are parts by mass), and further glass beads (Sekiya Rika Co., Ltd., 2 mm diameter) 200 mass A portion was added and stirred for 5 hours. After stirring, the glass beads were filtered through a mesh to obtain a titanium oxide-dispersed polyol liquid A6.

<Resin (a) having a hydroxyl group other than resin (A)>
(A-1) “Cotax LH-601” manufactured by Toray Fine Chemical Co., Ltd.
Solvent: Mixed solvent of toluene (SP value = 18.2) and n-butyl acetate (SP value = 17.4) Solid content: 50%
Hydroxyl value: 20 mgKOH / g
<Alkyl etherified melamine resin (B)>
≪ (B-1) Ethylated melamine resin solution≫
In a four-necked flask equipped with a stirrer, thermometer, reflux condenser and nitrogen inlet tube, 126 g (1.0 mol) of melamine, 196 g (6.0 mol) of paraformaldehyde having a formalin concentration of 92% and 276 g (6. 0 mol), and the temperature was raised to the reflux temperature. After carrying out methylolation reaction for 1 hour at reflux temperature, 0.180 g (0.53 mmol) of 50% aqueous solution of paratoluenesulfonic acid (water; SP value = 47.9) was added, and ethyl etherification was conducted under reflux condition. The reaction was carried out for 3 hours. Thereafter, the reaction product was neutralized with 0.160 g (0.80 mmol) of 20% sodium hydroxide solution, and then ethanol and water were distilled off under reduced pressure, followed by isobutanol (SP value = 23.5). The ethylated melamine resin solution (B-1) was obtained by diluting until the nonvolatile content became 70% by weight. The weight average molecular weight of the obtained resin was 2,000.

≪Butylated melamine resin≫
・ (B-2) "Uban 20SE60" manufactured by Mitsui Chemicals, Inc.
Solvent: xylene (SP value = 18.0) / n-butanol (SP value = 23.3) = 40/60 mixed solvent Solid content: 60%
Weight average molecular weight: 4,000
・ (B-3) "Uban 28-60" manufactured by Mitsui Chemicals, Inc.
Solvent: n-butanol (SP value = 23.3)
Solid content: 60%
Weight average molecular weight: 2,300
≪Methylated melamine resin≫
(B-4) “Cymel 327” manufactured by Daicel Ornex
Solvent: iso-butanol (SP value = 23.5)
Solid content: 90%
・ (B-5) "Cymel 370" manufactured by Daicel Ornex
Solvent: iso-butanol (SP value = 23.5)
Solid content: 88%
<Lewis acid catalyst (C)>
(C-1) to (C-7) shown in Table 1.

<Catalysts other than Lewis acid catalyst (C) (c ')>
(C′-1) to (c′-7) described in Table 1. Details of the catalysts (c′-4), (c′-5) and (c′-7) are as follows.
・ (C'-4) "Nikka Octix Zinc" manufactured by Nippon Chemical Industry Co., Ltd.
Ingredient: Zinc octylate (Zinc content: 18%)
(C′-5) “Neostan U-801” manufactured by Nitto Kasei Co., Ltd.
Ingredients: Di-n-butyltin dilaurate (c'-6) paratoluenesulfonic acid monohydrate (c'-7) "NACURE 4000" manufactured by KING INDUSTRIES
Ingredient: Alkyl phosphate ester <Solvent (D)>
・ N-Butyl acetate (SP value = 17.4)
・ Methyl isobutyl ketone (SP value = 17.2)
-Solvesso 100 (SP value = 18.0)
・ Toluene (SP value = 18.2)
・ Xylene (SP value = 18.0)
・ Water (SP value = 47.9)
・ Methanol (SP value = 29.7)
・ Ethanol (SP value = 26)
Iso-butanol (SP value = 23.5)
Iso-propanol (SP value = 23.5)
N-butanol (SP value = 23.3)
-Sec-butanol (SP value = 22.1)
Tetrahydrofuran (SP value = 18.8)
<Coating body (base material)>
・ Steel (made by Test Piece Co., Ltd., JIS-G3141 (SPCC, SB), 5Φ1 PB-N144, 150mm x 70mm x thickness 0.8mm)
Polycarbonate resin plate (“PC 1600” manufactured by Takiron Sea Eye Co., Ltd., 150 mm × 70 mm × thickness 2.0 mm, hereinafter also referred to as “PC substrate”)
Acrylic resin plate (“Acrylite L-001”, 150 mm × 70 mm × thickness 2.0 mm, manufactured by Mitsubishi Chemical Corporation), hereinafter also referred to as “PMMA substrate”. )
ABS resin plate (manufactured by Test Piece Co., Ltd., JIS, K, 6873 (ABS) black, 150 mm × 70 mm × thickness 2.0 mm, hereinafter also referred to as “ABS base material”)
PET film (“Lumirror U34” manufactured by Toray Industries, Inc., 300 mm × 150 mm × thickness 100 μm, hereinafter also referred to as “PET substrate”)
・ Zinc iron plate (JIS-G-3302) 150 mm x 300 mm x thickness 0.3 mm
[Evaluation items and methods]
<SP value (MPa1 / 2): Solubility Parameter>
“POLYMER HANDBOOK FOURTH EDITION” written by J. Brandrup et al., A WILEY-INTERSCIENCE, published on pages 676-697 was used as a reference.

<Catalyst solubility test>
Measure the catalyst (C) or (c ′) in a glass sample bottle, add the solvent (D) so that the concentration of the catalyst is 0.01% by mass or 1% by mass, and cover the sample with a 25 ° C. It was immersed for 2 minutes in an ultrasonic cleaner equipped with water ("US-3KS" manufactured by SNT Co., Ltd.) and subjected to ultrasonic waves. A sample having a completely uniform appearance was judged as “◯”, and a sample with undissolved residue was judged as “x”. The evaluation results are shown in Table 1.

<Appearance of composition (coating material)>
The compositions obtained in Examples and Comparative Examples were placed in transparent glass sample bottles, covered, and allowed to stand at 25 ° C. for 30 minutes. When the appearance is visually observed, “◎” when there is no precipitate or undissolved material, “◯” when there is uniform cloudiness but no separation / sedimentation is observed, and there is precipitate or undissolved material Was determined as “×”.

<Evaluation of storage stability of composition (coating material) and coating material>
After leaving the composition placed in a glass sample bottle at 25 ° C. for 8 hours, tilt the sample bottle and visually observe the appearance to show fluidity (the composition or the coating material flows). “O” indicates that no fluidity is observed (solidified).

<Appearance of coating film>
The coatings of the test plates with coatings obtained in the examples and comparative examples are visually observed. “◎” indicates that there is no foreign matter or the like and the surface is smooth. "A case where foreign matter or unevenness was observed on the entire surface, or a case where gloss was impaired was evaluated as" X ".

<Film durability evaluation: Xylene rubbing test>
The coating film surface of the test plate with a coating film obtained in Examples and Comparative Examples is obtained by immersing xylene in gauze, rubbing with a load of 300 g, and the first digit of the number of reciprocations until the surface of the material to be coated appears. Rounded off, 200 round trips or more were judged as “◎”, 100-190 rounds as “◯”, 30-90 rounds as “Δ”, and 0-20 rounds as “x”.

<Pencil hardness>
According to JIS K 5600-5-4, a pencil lead is applied at an angle of about 45 ° with respect to the test coating plate surface, and it is pressed to the test coating plate surface to the extent that the core does not break. I moved it. The hardness symbol of the hardest pencil with no scratches on the coating film was defined as pencil hardness.

［実施例Ａ１〜２９、比較例Ａ１〜２０］
水酸基を有する樹脂（Ａ）もしくは（ａ）、メラミン樹脂（Ｂ）、ルイス酸触媒（Ｃ）もしくは他の触媒（ｃ’）および溶剤（Ｄ）を表２〜４に示す割合で混合することにより、組成物（コーティング材）を調製して評価した。

[Examples A1 to 29, Comparative examples A1 to 20]
By mixing the hydroxyl group-containing resin (A) or (a), melamine resin (B), Lewis acid catalyst (C) or other catalyst (c ′) and solvent (D) in the ratios shown in Tables 2 to 4 A composition (coating material) was prepared and evaluated.

  The obtained composition was applied to a steel plate (150 mm × 70 mm × 0.8 mm thickness) using a bar coater so that the cured film thickness was 15 μm, and then the composition was cured by heating at 80 ° C. for 30 minutes. Thus, a test plate with a coating film was prepared and evaluated.

  The evaluation results are shown in Tables 2-4.

［実施例Ａ３０〜４５および比較例Ａ２１〜３９］
酸化チタン分散ポリオール液Ａ１、メラミン樹脂（Ｂ）、ルイス酸触媒（Ｃ）もしくは他の触媒（ｃ’）および溶剤（Ｄ）を表５〜７に示す割合で混合することにより、組成物（白色コーティング材）を調製して評価した。

[Examples A30 to 45 and Comparative examples A21 to 39]
By mixing the titanium oxide-dispersed polyol liquid A1, the melamine resin (B), the Lewis acid catalyst (C) or other catalyst (c ′) and the solvent (D) at a ratio shown in Tables 5 to 7, a composition (white A coating material was prepared and evaluated.

  The obtained composition was applied to a steel plate (150 mm × 70 mm × 0.8 mm thickness) using a bar coater so that the cured film thickness was 15 μm, and then the composition was cured by heating at 80 ° C. for 30 minutes. Thus, a test plate with a coating film was prepared and evaluated.

  The evaluation results are shown in Tables 5-7.

［実施例Ａ４６〜４８および比較例Ａ４０〜４３］
水酸基を有する樹脂（Ａ）、メラミン樹脂（Ｂ）、ルイス酸触媒（Ｃ）もしくは他の触媒（ｃ’）、ポリイソシアネート（旭化成（株）製「デュラネートＴＫＡ−１００」）および溶剤（Ｄ）を表８に示す割合で混合することにより、組成物（コーティング材）を調製して評価した。

[Examples A46 to 48 and Comparative Examples A40 to 43]
Resin having hydroxyl group (A), melamine resin (B), Lewis acid catalyst (C) or other catalyst (c ′), polyisocyanate (“Duranate TKA-100” manufactured by Asahi Kasei Co., Ltd.) and solvent (D) By mixing at the ratio shown in Table 8, a composition (coating material) was prepared and evaluated.

  After coating the obtained composition on the above PC base material, PMMA base material and ABS base material using a bar coater so that the cured film thickness becomes 15 μm, the composition is heated at 80 ° C. for 30 minutes. Then, a test plate with a coating film was prepared and evaluated by curing.

  The evaluation results are shown in Table 8.

［実施例Ａ４９〜５１］
水酸基を有する樹脂（Ａ）、メラミン樹脂（Ｂ）、ルイス酸触媒（Ｃ）および溶剤（Ｄ）を表９に示す割合で混合することにより、組成物（コーティング材）を調製して評価した。

[Examples A49 to 51]
A composition (coating material) was prepared and evaluated by mixing the resin (A) having a hydroxyl group, the melamine resin (B), the Lewis acid catalyst (C) and the solvent (D) in the ratio shown in Table 9.

  The obtained composition was coated on the above PET substrate using a bar coater so that the cured film thickness was 10 μm, and then the composition was heated at 120 ° C. for 30 seconds to be cured. A test plate with a film was prepared and evaluated.

  Table 9 shows the evaluation results.

［実施例Ｂ１〜３０、比較例Ｂ１〜２０］
水酸基を有する樹脂（Ａ）もしくは（ａ）、メラミン樹脂（Ｂ）、ルイス酸触媒（Ｃ）もしくは他の触媒（ｃ’）、溶剤（Ｄ）、および添加剤（Ｅ）を表１０〜１３に示す割合で混合することにより、コート材を調製した。

[Examples B1-30, Comparative Examples B1-20]
Tables 10 to 13 show the hydroxyl group-containing resin (A) or (a), melamine resin (B), Lewis acid catalyst (C) or other catalyst (c ′), solvent (D), and additive (E). A coating material was prepared by mixing at the indicated ratio.

  Thermolabel (R) -5E125 and 170 (manufactured by NOF Co., Ltd.) were attached to a zinc iron plate (150 mm × 300 mm × thickness 0.3 mm), and then the coating material was cured and dried on the opposite surface of the label After coating with a bar coater to a thickness of 15 μm, it was immediately put into an automatic discharge dryer ATO-102 (manufactured by Nippon Test Panel Industry Co., Ltd.) and heated at a predetermined temperature and time. Since the thermolabel discolors when it reaches each temperature in units of 10 ° C., the highest temperature at which discoloration was observed was defined as PMT.

  The PMT retention time was described as the time elapsed from the time when the coated plate was taken out of the oven every second by the above measurement method and the color change was seen. In addition, it examined by n = 2, and when there was what a label discolored and what did not, it was considered that it was discolored at the time.

  In the case of Example B1, when the two coated plates were placed in an oven at 160 ° C. and discharged after 34 seconds, the 120 ° C. label was discolored, but the 130 ° C. label was not discolored. When two separately coated plates were discharged at 160 ° C. after 35 seconds, one of the 130 ° C. labels was discolored, so it was considered that 130 ° C. had been reached in 34 to 35 seconds. Similarly, when two separately coated plates were discharged at 160 ° C. after 39 seconds, the 140 ° C. label was discolored, but the 150 ° C. label was not discolored.

  From the above results, PMT 140 ° C., the time during which the coated plate was held at 130 ° C. or higher reached 130 ° C. for 34 to 35 seconds, and the time of 4 to 35 to 39 seconds was held at least 130 ° C. or higher. Therefore, it was written as 4-5 seconds.

  The test plate with a coating film obtained as described above was evaluated. The evaluation results are shown in Tables 10-13.

Claims (24)

(A) Resin having a hydroxyl group having a solid hydroxyl value of 25 to 300 mgKOH / g (excluding the alkyl etherified melamine resin (B)),
(B) an alkyl etherified melamine resin,
(C) Lewis acid catalyst comprising a cation made of a metal having Pauling's electronegativity of 1.31 to 2.02 and a counter anion which is a deprotonated proton acid having an acid dissociation constant pKa of 1.0 or less. And (D) a solvent,
The hydroxyl group-containing resin (A) is at least one resin selected from the group consisting of a hydroxyl group-containing acrylic resin, a hydroxyl group-containing polyester resin, and a hydroxyl group-containing urethane resin,
The solvent (D) includes a solvent (D-1) having a Hildebrand solubility parameter value (SP value) of 18.6 to 47.9, and the solvent (D-1) relative to the total amount of the solvent (D) The content of is 21% by mass or more,
Among the said solvent (D-1), content of the solvent (DS) whose solubility of the said Lewis' acid catalyst (C) is 0.01 mass% or more is 4 with respect to the whole quantity of the said solvent (D). A thermosetting resin composition characterized by being at least mass%.   The thermosetting resin composition according to claim 1, wherein the Lewis acid catalyst (C) is at least one selected from the group consisting of nitrates, sulfates and halides.   The thermosetting resin composition according to claim 1 or 2, wherein the cation constituting the Lewis acid catalyst (C) comprises at least one metal selected from the group consisting of magnesium, aluminum and nickel. .   The thermosetting resin composition according to any one of claims 1 to 3, wherein the solvent (D-1) is at least one selected from the group consisting of alcohol and water. (E) at least selected from the group consisting of pigments, dyes, leveling agents, stability improvers, foam inhibitors, weather resistance improvers, anti-waxing agents, antioxidants, dispersants, wetting agents, thixotropic agents and ultraviolet absorbers. One type of additive is further included, The thermosetting resin composition as described in any one of Claims 1-4 characterized by the above-mentioned. The mass ratio (A / B) of the solid content of the resin (A) having a hydroxyl group and the solid content of the alkyl etherified melamine resin (B) is 95/5 to 45/55. The thermosetting resin composition as described in any one of 1-5 . The content of the Lewis acid catalyst (C) is in the range of 0.01 to 5 parts by mass with respect to a total of 100 parts by mass of the solid content of the hydroxyl group-containing resin (A) and the alkyl etherified melamine resin (B). It is a thermosetting resin composition as described in any one of Claims 1-6 characterized by the above-mentioned. A cured product comprising the thermosetting resin composition according to any one of claims 1 to 7 . Method for producing a cured product comprising the claims 1-7 step of heating and curing the thermosetting resin composition according to the temperature of 60 to 125 ° C. in any one of. The method for producing a cured product according to claim 9 , wherein the heating time in the step is in the range of 10 seconds to 60 minutes. A laminate comprising a cured film comprising the thermosetting resin composition according to any one of claims 1 to 7 . A method for producing a laminate including a covering and a cured film,
Forming a coating film by applying a thermosetting resin composition according to the covering body in any one of claims 1 to 7
And a step of heating the coating film at a temperature of 60 to 125 ° C. to form a cured film. The method for producing a laminate according to claim 12 , wherein the covering is a metal or a resin. (A) Resin having a hydroxyl group having a solid hydroxyl value of 25 to 300 mgKOH / g (excluding the alkyl etherified melamine resin (B)),
(B) an alkyl etherified melamine resin,
(C) Lewis acid catalyst comprising a cation made of a metal having Pauling's electronegativity of 1.31 to 2.02 and a counter anion which is a deprotonated proton acid having an acid dissociation constant pKa of 1.0 or less. ,
(D) Solvent, and (E) From pigments, dyes, leveling agents, stability improvers, foam inhibitors, weather resistance improvers, anti-waxing agents, antioxidants, dispersants, wetting agents, thixotropic agents and UV absorbers At least one additive selected from the group consisting of:
The hydroxyl group-containing resin (A) is at least one resin selected from the group consisting of a hydroxyl group-containing acrylic resin, a hydroxyl group-containing polyester resin, and a hydroxyl group-containing urethane resin,
The solvent (D) includes a solvent (D-1) having a Hildebrand solubility parameter value (SP value) of 18.6 to 47.9, and the solvent (D-1) relative to the total amount of the solvent (D) The content of is 21% by mass or more,
Among the said solvent (D-1), content of the solvent (DS) whose solubility of the said Lewis' acid catalyst (C) is 0.01 mass% or more is 4 with respect to the whole quantity of the said solvent (D). Mass% or more,
Content of the said additive (E) is 10 to 300 mass parts with respect to a total of 100 mass parts of the said resin (A) and resin (B), The coating material for precoat metals characterized by the above-mentioned . 15. The precoat metal coating material according to claim 14 , wherein the Lewis acid catalyst (C) is at least one selected from the group consisting of nitrates, sulfates and halides. 16. The precoat metal coating material according to claim 14, wherein the cation constituting the Lewis acid catalyst (C) comprises at least one metal selected from the group consisting of magnesium, aluminum and nickel. The solvent (D-1) is precoated metals for coating material according to any one of claims 14 to 16, wherein the at least one selected from the group consisting of alcohol and water. The mass ratio (A / B) of the solid content of the resin (A) having a hydroxyl group and the solid content of the alkyl etherified melamine resin (B) is 95/5 to 45/55. precoated metals for coating material according to any one of 14-17. The content of the Lewis acid catalyst (C) is in the range of 0.01 to 5 parts by mass with respect to a total of 100 parts by mass of the solid content of the hydroxyl group-containing resin (A) and the alkyl etherified melamine resin (B). The coating material for a precoat metal according to any one of claims 14 to 18 , wherein the coating material is a precoat metal. Cured product, comprising the precoated metals for coating material according to any one of claims 14-19. Curing claim precoated metals for coating material according to any one of claims 14-19, characterized in that it comprises a step of curing by heating under the following conditions 250 ° C. or less and 5 seconds peak metal temperature 120 ° C. or higher Manufacturing method. A laminated body comprising a cured film made of the coating material for a precoat metal according to any one of claims 14 to 19 . A method for producing a laminate including a covering and a cured film,
Forming a coating film by coating a precoated metal for coating material according to the coating material to any one of claims 14-19,
And a step of heating the coating film under a condition of a peak metal temperature of 120 ° C. or higher and 250 ° C. or lower and 5 seconds or shorter to form a cured film. The method for manufacturing a laminate according to claim 23 , wherein the covering is a metal or a resin.