JP2005230719A - Two-pack polyurethane coating film excellent in heat resistance - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a two-pack polyurethane coating film excellent in heat resistance formed by a spray-coating method. <P>SOLUTION: The two-pack polyurethane coating film is obtained by spraying two liquids of a primary agent (A) containing a urethane prepolymer containing a terminal isocyanate group and a hardener (B) containing an active-hydrogen-containing compound and an organic acid bismuth salt as a catalyst at a ratio of the organic acid bismuth salt to the sum of the primary agent and the hardener of 0.002-0.2 wt.% by a spray-coating method using a high-pressure two-pack sprayer. The coating film keeps various intrinsic characteristics of the coating film, and is excellent in heat resistance. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a two-component polyurethane coating film excellent in heat resistance.
Specifically, it is obtained by reacting a main agent (A) containing a terminal isocyanate group-containing urethane prepolymer with a curing agent (B) containing an active hydrogen-containing compound and an organic acid bismuth salt as a curing catalyst by a spray method. It is a two-component polyurethane coating excellent in heat resistance.

The two-component polyurethane coating by the ultra-fast curing type urethane spraying system is excellent in various physical properties of the coating, and the construction is safe and workable due to the characteristics of the material and spray method. It has been widely put to practical use in the waterproofing of coatings on structures and the coating floor method.
As for the polyurethane coating film obtained by such a two-component spray method, those having excellent physical properties are increasingly being provided to the market due to the development and examination of materials to be used.
In waterproofing floors and structures, the coating film is applied on a base such as concrete or a heat insulating material laminated on the base, and is exposed to sunlight, rainwater, or the like.
In recent years, due to the demand for energy-saving houses, an outer heat insulation method in which a heat insulating material (urethane foam, styrene foam, etc.) is applied to the outside (atmosphere side) of a concrete frame has become widespread. In residential construction, the outside of the building is covered with a heat insulating material, and the indoor temperature of the building is maintained at a desired temperature without being affected by the outside air temperature, whether it is summer or winter. There is no damage caused by condensation, no problems with ticks and fleas resulting from condensation, which is preferable for health and hygiene, and is preferred for efficient use of thermal energy and maintenance of the global environment. The standard method has also been applied.

In this system, a heat insulating material is applied to the outside of the building. In order to provide waterproof performance to the heat insulating material layer, the surface is further protected by a waterproof layer made of the waterproof material.
Thus, when it consists of a heat insulating material layer and a waterproof layer, when it receives irradiation of sunlight, the heat absorbed by the heat insulating material layer is stored in the waterproof layer due to the heat insulating effect of the heat insulating material layer. Remarkably high temperatures close to 0C may be reached. As a result, the polyurethane coating itself deteriorates, and the phenomenon of swelling and peeling occurs between the insulation layer and the waterproof coating layer, which not only impairs the appearance and performance of the building, but also protects the coating. And the waterproof function is impaired. For this reason, it is desirable that the polyurethane waterproof coating itself has excellent heat resistance.
In order to improve the heat resistance of a polyurethane coating film, the search and development of isocyanates and polyols as appropriate raw materials have been conducted.
For example, in JP-A-2000-73008, a curing agent containing an aromatic polyamine chain extender consisting of diethyltoluenediamine and a polyol is used as an isocyanate-terminated urethane prepolymer comprising a norbornane diisocyanate and a polyol as a main agent. It is disclosed that a room temperature curable polyurethane coating waterproofing material that reacts with water is excellent in heat resistance.
However, this method is a hand coating mainly showing an appropriate pot life and curability for repair, and no proposal for improving the heat resistance of a two-component polyurethane coating by a spray method is found.

As a prior patent related to the present invention,
There exists Unexamined-Japanese-Patent No. 2000-73008.

The inventors of the present invention have made extensive studies on improvement of heat resistance in connection with the two-component polyurethane coating film produced by the spray method. The main agent containing a terminal isocyanate group-containing urethane prepolymer, an active hydrogen-containing compound, and a curing catalyst. A two-component polyurethane coating film obtained by reacting the contained curing agent with a spray method, wherein the curing catalyst is an organic acid bismuth salt, and the amount is 0.002 based on the total amount of the main agent and the curing agent. It was found that a two-component polyurethane coating film obtained by reacting two solutions by a spray method using an amount of ˜0.2% by weight has excellent heat resistance, and reached the present invention.
That is, the present invention
1. The heat resistance obtained by reacting the main component (A) containing the terminal isocyanate group-containing urethane prepolymer with the active hydrogen-containing compound and the curing agent (B) containing the organic acid bismuth salt as a curing catalyst by a spray method. Excellent two-component polyurethane coating,
2. The two-component polyurethane coating film excellent in heat resistance according to item 1, wherein the amount of the organic acid bismuth salt used is 0.002 to 0.2% by weight based on the total amount of the main agent and the curing agent as metal bismuth,
3. The two-component polyurethane coating film having excellent heat resistance according to item 1 or 2, characterized in that there is no difference in physical properties of the coating film after heat treatment at 100 ° C. for 2 weeks as compared with normal conditions. ,
It is.

The two-component polyurethane coating film of the present invention is excellent in heat resistance.
In other words, the coating film of the present invention has high heat resistance, extremely little deterioration over time even when placed in a natural environment and at a high temperature, and is originally excellent in various performances. Furthermore, the heat resistance which was further excellent to the 2 liquid type polyurethane coating film was provided.
Therefore, the two-component polyurethane coating film of the present invention can be preferably applied to floors, walls, roofs, and the like of an outer heat insulation system, and a waterproof layer that satisfies the performance required for reduction of deterioration and thermal environment can be applied. Become. It is extremely useful industrially as various waterproof coatings and protective coatings that require heat resistance, including waterproof coatings for waterproofing exterior heat-insulating passages and insulation materials for buildings.

The two-component polyurethane coating film of the present invention is sprayed with a main agent (A) containing a terminal isocyanate group-containing urethane prepolymer, and a curing agent (B) containing an active hydrogen-containing compound and an organic acid bismuth salt as a curing catalyst. It is obtained by reacting by the construction method.
The terminal isocyanate group-containing urethane prepolymer used in the main agent (A) is a compound having an isocyanate group, for example, an aromatic isocyanate, an aliphatic isocyanate, an alicyclic isocyanate, a mixture thereof, or a modification of an organic isocyanate compound such as a urethane prepolymer. It is obtained by reacting a compound having an active hydrogen that reacts with an isocyanate, that is, an active hydrogen-containing compound such as a polyol compound or a polyamine compound having two or more hydroxyl groups at the molecular ends.
Examples of the compound having an isocyanate group include tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), xylylene diisocyanate (XDI), tetramethylxylylene diisocyanate (TMXDI), 1,5-naphthalene diisocyanate (NDI), and liquid. Aromatic isocyanates such as diphenylmethane diisocyanate (liquid MDI), crude tolylene diisocyanate (crude TDI), polymethylene polyphenyl polyisocyanate (crude MDI), aliphatic isocyanates such as hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI) ), Hydrogenated XDI (H6XDI), hydrogenated MDI (H12MDI), hydrogenated tetramethyl XDI, norbornane diisocyanate They include aromatic polyisocyanates such as methyl (NBDI).

Further, isocyanate group-terminated prepolymers using these isocyanates, carbodiimide modified products, uretonimine modified products, acylurea diisocyanates, isocyanurate modified products, trimethylolpropane adducts, biuret modified products, and allophanate modified products are also included.
Preferably, it is an MDI polyisocyanate and / or a modified product thereof. These compounds having an isocyanate group may be used alone or in combination of two or more.

A compound containing an active hydrogen that reacts with an isocyanate (sometimes simply referred to as an active hydrogen-containing compound) is a polyol compound or a polyamine compound having two or more hydroxyl groups at a molecular end, and is a typical preparation of a polyurethane resin composition. Active hydrogen-containing compounds used in
For example, as a relatively low molecular weight polyhydric alcohol, ethylene glycol (EG), diethylene glycol (DEG), propylene glycol (PG), dipropylene glycol (DPG), 1,3-butanediol (1,3-BD), Dihydric alcohols such as 1,4-butanediol (1,4-BD), neopentyl glycol (NPG), 4,4′-dihydroxyphenylpropane, 4,4′-dihydroxyphenylmethane, glycerin, 1,1, Examples thereof include trihydric alcohols such as 1-trimethylolpropane (TMP) and 1,2,5-hexanetriol, and tetrahydric or higher polyhydric alcohols such as pentaerythritol, glucose, sucrose, and sorbitol.

As the polyether polyol, for example, one or more types of relatively low molecular weight polyhydric alcohols, or one or more types of low molecular weight amine compounds such as ethylenediamine and aniline, ethylene oxide, propylene oxide, butylene oxide or the like Examples include polyether polyols obtained by addition polymerization of two or more, or polytetramethylene ether glycol (PTMEG) obtained by ring-opening polymerization of tetrahydrofuran.
Examples of the polyester polyol include ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, glycerin, trimethylolpropane and the like, or one or more other low molecular weight polyols, glutaric acid, adipic acid, sebacic acid, terephthalate. Examples thereof include polyester polyols obtained by condensation polymerization with one or more of acid, isophthalic acid, dimer acid or the like or other low molecular dicarboxylic acid or oligomeric acid and ring-opening polymerization of caprolactone.

Furthermore, the polyester polyether polyol etc. which are obtained by addition-polymerizing 1 type (s) or 2 or more types, such as ethylene oxide, a propylene oxide, butylene oxide, to the said well-known polyester polyol, etc. are mentioned.
Examples of the modified product of the polyether polyol or polyester polyol include polymer polyols obtained by graft polymerization of ethylenically unsaturated compounds such as acrylonitrile, styrene and methyl methacrylate to the known polyether polyol or polyester polyol.
Examples of other polyols include polycarbonate polyol, polybutadiene polyol, hydrogenated polybutadiene polyol, acrylic polyol, epoxy polyol, and castor oil.
Examples of the polyamine compound include aliphatic polyamines and aromatic polyamines such as ethylenediamine and polyether polyamine.
These active hydrogen-containing compounds can be used singly or in combination of two or more.

The terminal isocyanate group-containing urethane prepolymer preferably comprises a compound containing an isocyanate group at the terminal and a polyol compound having two or more hydroxyl groups at the molecular terminal as an active hydrogen-containing compound at an NCO / OH ratio of 4 to 25. The reaction is carried out (in the case where the active hydrogen compound is a polyamine compound, the ratio is NCO / H).
There is no particular limitation on the method for synthesizing the urethane prepolymer. For example, the isocyanate group-containing compound can be combined with the active hydrogen-containing compound within the above NCO / OH ratio (or NCO / H ratio) range with respect to the active hydrogen-containing compound. Then, mixing or one of them is charged first, the other is added later, and a known catalyst can be added and reacted for 10 to 120 ° C. and 1 to 150 hours, if necessary, to accelerate the reaction.

The main agent (A) and the curing agent (B) include plasticizers suitable for plastics conventionally used in the production of polyurethane resins, such as dibutyl phthalate (DBP) and di-n-octyl phthalate. Plasticizers such as esters (DnOP), phthalic acid di (2-ethylhexyl) ester (DOP), adipic acid di (2-ethylhexyl) ester (DOA), or fatty acid esters can be used.
Moreover, when using a plasticizer, the usage-amount is 1 to 25 weight% with respect to the total amount of a main ingredient and a hardening | curing agent, and considers the viscosity of a main ingredient liquid and a hardening | curing agent liquid as follows, and a main ingredient. It may be added separately to the curing agent or may be added to either one.

  In the spray method, the viscosity of the main agent and the curing agent is preferably about 300 to 600 mPa at normal temperature. When applied to spray construction, the main agent and the curing agent are heated in the apparatus, respectively, and the viscosity is about 100 mPa at a desired temperature. It is preferable to reduce, maintain the temperature, send to the spray gun, mix the two liquids, and spray the work (object).

The curing agent (B) used in the present invention contains an active hydrogen-containing compound and an organic acid bismuth salt.
The active hydrogen-containing compound is usually a polyol having two or more hydroxyl groups in one molecule or a polyamine having two or more amino groups in one molecule, and the polyol and polyamine may be used in combination.
Examples of the polyol include polyhydric alcohols having a relatively low molecular weight, polyether polyols, polyester polyols, polyether polyols, and modified polyester polyols.

  Examples of the relatively low molecular weight polyhydric alcohol include ethylene glycol (EG), diethylene glycol (DEG), propylene glycol (PG), dipropylene glycol (DPG), and 1,3-butanediol (1,3-BD). 1,2-butanediol (1,4-BD), neopentyl glycol (NPG), 4,4′-dihydroxyphenylpropane, dihydric alcohols such as 4,4′-dihydroxyphenylmethane, glycerin, 1,1 , 1-trimethylolpropane (TMP), trivalent alcohols such as 1,2,5-hexanetriol, and tetrahydric or higher polyhydric alcohols such as pentaerythritol, glucose, sucrose, and sorbitol.

In addition, as the polyether polyol, for example, a polyether polyol and tetrahydrofuran obtained by addition polymerization of one or more kinds such as ethylene oxide, propylene oxide, and butylene oxide to one or more kinds of relatively low molecular weight polyhydric alcohols can be opened. Examples thereof include polytetramethylene ether glycol (PTMEG) obtained by polymerization.
Examples of the polyester polyol include ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, glycerin, trimethylolpropane and the like or one or more of other low-molecular polyols, glutaric acid, adipic acid, and sebacic acid. And polyester polyols obtained by condensation polymerization with one or more of low molecular dicarboxylic acids and oligomeric acids and ring-opening polymerization of caprolactone, etc., terephthalic acid, isophthalic acid, dimer acid and the like.

Examples of the modified product of the polyether polyol or polyester polyol include polymer polyols obtained by graft polymerization of ethylenically unsaturated compounds such as acrylonitrile, styrene and methyl methacrylate to the known polyether polyol or polyester polyol.
Examples of other polyols include polycarbonate polyol, polybutadiene polyol, hydrogenated polybutadiene polyol, acrylic polyol, epoxy polyol, and castor oil.
When such a modified product of polyether polyol or polyester polyol is used as the active hydrogen-containing compound, the amount used may be appropriately set according to the purpose and physical properties of the polyurethane to be obtained.

  Examples of the polyamine include aliphatic polyamines such as ethylenediamine and polyether polyamine, and aromatic diamines such as diethyltoluenediamine and 4,4'-methylenebis- (2-chloroaniline).

As the catalyst contained in the curing agent (B) in the present invention, an organic acid bismuth salt is used, and examples thereof include an organic acid bismuth salt or a fatty acid bismuth salt having 8 to 20 carbon atoms.
Examples of the organic acid bismuth salt include alicyclic organic acids such as abietic acid, neoabietic acid, d-pimalic acid, iso-d-pimalic acid, podocarpic acid, and bismuth resin acid resin mainly composed of two or more of these. And bismuth salts of aromatic organic acids such as benzoic acid, cinnamic acid and p-oxycinnamic acid. Examples of the fatty acid bismuth salt having 8 to 20 carbon atoms include bismuth salts such as octylic acid, neodecanoic acid and neododecanoic acid.
The amount of the organic acid bismuth salt used is 0.002 to 0.2% by weight, preferably 0.002 to 0.15% by weight as metal bismuth with respect to the total amount of the main agent and the curing agent. The organic acid bismuth salt is contained in the curing agent. In a hardening | curing agent, it can adjust and contain so that it may become the said usage-amount with respect to the total amount by the quantity ratio of the main ingredient made to react and a hardening | curing agent. If it is less than 0.002% by weight, curing is insufficient, and if it exceeds 0.2% by weight, the physical properties of the coating film deteriorate.
In the coating film of the present invention, the main agent and the curing agent can be reacted in an amount ratio of 1: 4 to 4: 1. Among them, as a metal bismuth, 0.0025 to 0.25% by weight, and a curing agent when reacted at 1: 1, 0.004 to 0.4% by weight as a metal bismuth, and further 4 The curing agent used for the reaction at 1: may be adjusted to contain 0.01 to 1.0% by weight as metal bismuth.

The organic acid bismuth salt used in the present invention may further contain an organic acid exhibiting an effect such as a promoter. Examples of the organic acid include aromatic carboxylic acids such as benzoic acid, phthalic acid, and o-chlorobenzoic acid, and aliphatic carboxylic acids such as 2-ethylhexanoic acid, octylic acid, stearic acid, oleic acid, and linoleic acid. . Preferably, 2-ethylhexanoic acid is excellent in compatibility with the polyol and easy to use and is frequently used.
When the organic acid is used in combination with the organic acid bismuth salt, the amount of the organic acid added is 0.01 to 5% by weight, preferably 0.01 to 1% by weight, based on the total amount of the curing agent.

In addition, chain extenders, fillers, anti-aging agents, UV absorbers, light stabilizers, antioxidants, pigments or dye colorants, dispersants, plasticizers, etc. may be added to the curing agent as necessary. You may mix | blend an agent arbitrarily.
Moreover, it can also use as a foam by adding a foam stabilizer and a foaming agent according to a use. As long as these other additives are within the range not impairing the effects of the present invention, a part or all of the blending amount may be blended with the main agent.

The two-component polyurethane coating film of the present invention is obtained by spraying the above-mentioned main agent and curing agent on a construction object by a high-pressure two-component spraying device, and reacting and curing.
In this case, the main agent and the curing agent are used in a volume ratio of 4: 1 to 1: 4, NCO Index (equivalent ratio of NCO group in the terminal isocyanato group-containing urethane prepolymer and active hydrogen in the curing agent). Is in the range of 0.9 to 1.3, preferably 1 to 1.2.

Conventionally, JIS A 6021 has been the standard for heat resistance of room temperature curable urethane building materials. In this test method, the load in the heat resistance test is 80 ° C. × 7 days (1 week).
On the other hand, in the Architectural Institute of Japan, in the reference material 2 “Durability Performance Test Method for Membrane Waterproof Layer (Draft)” of “Standard Specification for Building Construction / Explanation JASS8 Waterproofing”, “Resistance to heat due to solar radiation of waterproofing layer” As a deterioration test method for the purpose of "evaluation of", a load of 80 ° C x 112 days for a concrete base and 90 ° C x 112 days for a heat insulating base is proposed. Thus, in the test method proposed by the Architectural Institute of Japan, stricter test temperatures and periods are set compared to the test method of JIS standard.

In the evaluation of heat resistance in the present invention, more severe temperature conditions were set, but the test period was set to a period during which a practical test can be performed, that is, 100 ° C. × 2 weeks.
The test was conducted as follows. As shown in the Examples, a coating film was formed, left standing at 23 ° C. for 7 days, measured for normal physical properties, then allowed to stand at 100 ° C. for 2 weeks, and measured physical properties showing heat resistance. Therefore, in the present invention, excellent heat resistance means that no change appears even when the coating film is placed at 100 ° C. for 2 weeks as described above.
The two-component polyurethane coating film of the present invention shows an evaluation result excellent in heat resistance, and the polyurethane coating film of the present invention shows that the physical properties of the coating film are not damaged for a long time even when placed in a natural environment. This effect was superior to the polyurethane coating film using a lead compound as a curing catalyst in the two-component polyurethane coating film of the present invention.

Hereinafter, in order to explain the present invention concretely, examples and comparative examples will be described.
Example-1
Adjustment of main agent Cosmonate PH (Pure MDI: manufactured by Mitsui Takeda Chemical Co., Ltd.) 27.335 parts by weight, Cosmonate LK (carbodiimide modified MDI: manufactured by Mitsui Takeda Chemical Co., Ltd.) 9.112 parts by weight, and Actol D-3000 (number) An average molecular weight of 3,000 polypropylene ether diol: made by Mitsui Takeda Chemical Co., Ltd. (53.553 parts by weight) was reacted at 90 ° C. for 3 hours in the presence of 10.000 parts by weight of DOP (phthalic acid di (2-ethylhexyl) ester). Thus, a prepolymer having an NCO% of 10 and a viscosity of 950 mPa · s / 25 ° C. was obtained.
Adjustment of curing agent Actol ED-56 (polyethylene propylene ether diol having a number average molecular weight of 2000: manufactured by Mitsui Takeda Chemical) 87.806 parts by weight, MEG # 100 (monoethylene glycol: manufactured by Mitsui Chemicals) 0.894 parts by weight Ethacure # 100 (diethyltoluenediamine: manufactured by Albemarle Asano Co., Ltd.) 10.000 parts by weight, Pucat 25 (bismuth octylate: bismuth content 25%: manufactured by Nippon Chemical Industry Co., Ltd.) 1.000 parts by weight, Tinuvin B-75 (3 Seed mixed liquid stabilizer: Ciba Geigy Co., Ltd.) 0.300 parts by weight was mixed to prepare a mixed solution having a viscosity of 500 mPa · s / 25 ° C.
Spraying was performed using a gas mer H-20 spray machine at 1/1 (volume ratio) of the main agent and curing agent and NCO Index 1.1. Liquid feeding to the spray machine was performed by applying a 0.5 MPa air pressure to a Graco supply pump (air driven 2: 1 type). The spray machine was used at a stationary pressure of 12 MPa and at a spraying of 10 to 11 MPa.
The temperature of the liquid was adjusted to a main agent primary heater of 65 ° C, a curing agent primary heater of 65 ° C, and a hose heater of 60 ° C.
The spray gun was sprayed using a round chamber # 1 of a glass gun probler gun.
As the mold, a polypropylene plate having a thickness of about 1.5 mm was used, and lamination was performed 3 to 5 times to obtain a sheet having a thickness of about 2 mm.
After the obtained sheet was placed in a standard state for 7 days at 23 ° C. and relative humidity (50 ± 10)%, and then further placed in a high temperature atmosphere at 100 ° C. for 2 weeks, the following test was performed. .
Tensile strength, elongation, and tear strength were determined in accordance with JIS A6021 architectural waterproofing coating material. The hardness was determined in accordance with the hardness test method for JIS K6253 vulcanized rubber and thermoplastic rubber.
The results are summarized in Table 1.

Example-2
Adjustment of main agent Cosmonate PH (Pure MDI: manufactured by Mitsui Takeda Chemical Co.) 37.353 parts by weight, Cosmonate LK (carbodiimide modified MDI: manufactured by Mitsui Takeda Chemical Co., Ltd.) 12.451 parts by weight, and Actcoal D-2000 (number) Polypropylene ether diol having an average molecular weight of 2000: Mitsui Takeda Chemical Co., Ltd. (42.197 parts by weight) and Fine ester R-1000 (Nuka fatty acid ester: Miyoshi Oil & Fats Co., Ltd.) in the presence of 8.000 parts by weight By reacting for a time, a prepolymer having an NCO% of 14 and a viscosity of 550 mPa · s / 25 ° C. was obtained.
Adjustment of curing agent Actol EP-550N (polyethylene propylene ether triol having a number average molecular weight of 2000: manufactured by Mitsui Takeda Chemical Co., Ltd.) 76.463 parts by weight, Ethacure # 100 (diethyltoluenediamine: manufactured by Albemarle Asano Co., Ltd.) 22.237 parts by weight , Pcatt B7 (bismuth resinate: 7% bismuth content: manufactured by Nippon Kagaku Sangyo Co., Ltd.) 1.000 parts by weight, Tinuvin B-75 (three kinds of mixed liquid stabilizers: Ciba Geigy Co., Ltd.) 0.300 parts by weight, viscosity A mixed solution of 600 mPa · s / 25 ° C. was prepared.
Sheet preparation and physical property tests were performed in the same manner as in Example-1. The results are summarized in Table 1.

Example-3
Adjustment of main agent Cosmonate PH (Pure MDI: manufactured by Mitsui Takeda Chemical Co., Ltd.) 44.195 parts by weight, Cosmonate LK (carbodiimide-modified MDI: manufactured by Mitsui Takeda Chemical Co., Ltd.) 14.731 parts by weight, and Actol MN-3050one (number) 41.073 parts by weight of polypropylene ether triol having an average molecular weight of 3000 (manufactured by Mitsui Takeda Chemical Co., Ltd.) was reacted at 90 ° C. for 3 hours to obtain a prepolymer having NCO% 17 and a viscosity of 450 mPa · s / 25 ° C.
Adjustment of curing agent Actol D-2000 (polypropylene ether diol having a number average molecular weight of 2000: manufactured by Mitsui Takeda Chemical Co., Ltd.) 59.019 parts by weight, Actol AE300 (polypropylene ether polyol having a number average molecular weight of 700: manufactured by Mitsui Takeda Chemical Co., Ltd.) 16.681 parts by weight, Ethacure # 100 (diethyltoluenediamine: Albemarle Asano Co., Ltd.) 23.000 parts by weight, coscat # 83 (bismuth neodecanoate: 16% bismuth content: made by CasChem) 1.000 parts by weight, Tinuvin B -75 (3 types of mixed liquid stabilizers: Ciba Geigy Co., Ltd.) 0.300 parts by weight were mixed to prepare a mixed solution having a viscosity of 400 mPa · s / 25 ° C.
Sheet preparation and physical property tests were performed in the same manner as in Example-1. The results are summarized in Table 1.

Example-4
The same procedure as in Example 1 was performed except that 1.000 parts by weight of coscat 83 in Example-3 was used as 2.000 parts by weight.
Sheet preparation and physical property tests were performed in the same manner as in Example-1. The results are summarized in Table 1.

Comparative Example-1
Example 1 was performed except that 1.000 parts by weight of PACCAT 25 in Example-1 was used as 2.000 parts by weight. Sheet preparation and physical property tests were performed in the same manner as in Example-1. The results are summarized in Table 1.

Comparative Example-2
It carried out similarly to Example 1 except having used Minico P-25 (Lead octylate: Lead content 25%: Active material chemical company make) instead of the pucat 25 in Example-1.
Sheet preparation and physical property tests were performed in the same manner as in Example-1. The results are summarized in Table 1.

Cosmonate PH: Pure MDI; Cosmonate LK manufactured by Mitsui Takeda Chemical Co., Ltd. LK: Carbodiimide modified MDI; Actcol D-3000 manufactured by Mitsui Takeda Chemical Co., Ltd .: Polypropylene ether diol having a number average molecular weight of 3000;
Actol D-2000 manufactured by Mitsui Takeda Chemical Co., Ltd .: Polypropylene ether diol having a number average molecular weight of 2000;
Actol MN-3050 manufactured by Mitsui Takeda Chemical Co., Ltd .: Polypropylene ether trio having a number average molecular weight of 3000
Luo; Mitsui Takeda Chemical Co., Ltd. DOP: Phthalic acid di (2-ethylhexyl) ester fine ester R-1000: Nuka fatty acid ester;
L: Actol EP-550N manufactured by Mitsui Takeda Chemical Co .: Polyethylene propylene ether having a number average molecular weight of 2000
Reol; Actol AE-300 manufactured by Mitsui Takeda Chemical Co., Ltd .: Polypropylene ether polyol having a molecular weight of 700; Takeshi Mitsui
Ethacure # 100 manufactured by Tada Chemical Co., Ltd .: Diethyltoluenediamine; Alcatel Asano Co., Ltd. Pcat B-7: Resin acid bismuth; Bismuth metal content 7%; Nippon Kagaku Sangyo Cocat 25: Bismuth octylate; Japan Chemical Industry Co., Ltd.
MEG # 100: Monoethylene glycol; Tinuvin B-75: Mitsui Chemicals Co., Ltd .: Three mixed liquid stabilizer; Coscat 83: Bismuth neodecanoate; 16% bismuth content; Cas Chem
MINICO P-25: Lead octylate; 25% lead content

  The two-component polyurethane coating film by the spray method of the present invention is excellent in heat resistance. The catalyst used has no environmental hygiene concerns, and since it is a spray method, it is excellent in workability and stability, and is extremely useful industrially as a method that replaces the construction method that has been practically used.

Claims (3)

  The heat resistance obtained by reacting the main component (A) containing the terminal isocyanate group-containing urethane prepolymer with the active hydrogen-containing compound and the curing agent (B) containing the organic acid bismuth salt as a curing catalyst by a spray method. Excellent two-component polyurethane coating.   The two-component polyurethane coating film excellent in heat resistance according to claim 1, wherein the amount of the organic acid bismuth salt used is 0.002 to 0.2% by weight, based on the total amount of the main agent and the curing agent, as metal bismuth. . 3. A two-component polyurethane coating film with excellent heat resistance according to claim 1 or 2, wherein the coating film properties after heat treatment at 100 [deg.] C. for 2 weeks are not different from those of a normal state. .