Urea resin composition and polyurea foam

Abstract

The present invention provides a urea resin composition for a polyurea foam that can provide excellent flame retardancy and shape retention during combustion, can suppress deterioration over time in a humid and hot environment, has excellent adhesiveness to an adherend during coating, is not likely to generate cracks even when in contact with a flame, and is not likely to undergo carbonization deep into the foam. A urea resin composition containing a polyisocyanate compound (A), a polyamine compound (B), a trimerization catalyst, a foaming agent, a foam stabilizer, and a flame retardant.

Description

Technical Field

[0001] The present invention relates to a urea resin composition and a polyurea foam. Background Art

[0002] Urethane foams are used as heat insulating materials and heat shielding materials for building applications, ships for oil and gas transportation, and electrical products such as refrigerators. Particularly in buildings constructed of reinforced concrete, etc., heat insulation construction is easy, and thus a method of applying a urethane foam by a spraying process is adopted. The spraying process is a process of forming a urethane foam heat insulation structure by spraying a stock solution of a urethane foam onto a building body using a spraying device while causing it to foam.

[0003] Generally, polyurethane resins have the following characteristics: excellent elasticity, flexibility, and tensile strength, and also exhibit excellent wear resistance and impact strength. However, in the case of a urethane foam alone, since its flammability is high, research has been conducted on improving the flame retardancy of the urethane foam.

[0004] As such a urethane foam, Patent Document 1 discloses a composition for forming a water-blown rigid polyisocyanurate foam composed of an organic polyphenylmethane polyisocyanate, a polyol, a trimerization catalyst, water as a foaming agent, a foam stabilizer, and a flame retardant. The invention of Patent Document 1 is characterized in that the polyol contains a chlorinated polyether polyol having a primary hydroxyl group and / or a secondary hydroxyl group obtained by ring-opening polymerization of a chlorinated epoxy compound in the presence of an acid catalyst using an active hydrogen compound as a polymerization initiator, and is characterized in that the organic polyphenylmethane polyisocyanate and the polyol are blended such that the isocyanate index is 120 to 400. The urethane foam using the composition for forming a water-blown rigid polyisocyanurate foam of Patent Document 1 exhibits excellent work environment, etc. and excellent flame retardancy.

[0005] Patent Document 2 discloses a flame-retardant urethane resin composition containing a polyisocyanate compound, a polyol compound, a trimerization catalyst, a foaming agent, a foam stabilizer, and an additive. The trimerization catalyst is at least one selected from the group consisting of a nitrogen-containing aromatic compound, a carboxy alkali metal salt, a tertiary ammonium salt, and a quaternary ammonium salt. The additive contains red phosphorus as an essential component, and in addition to red phosphorus, is combined with at least one selected from the group consisting of a phosphate ester, a phosphate-containing flame retardant, a bromine-containing flame retardant, a boron-containing flame retardant, an antimony-containing flame retardant, and a metal hydroxide. The urethane foam using the flame-retardant urethane resin composition of Patent Document 2 exhibits a foam that can be easily formed, has excellent flame retardancy, and maintains a certain shape when heated.

[0006] Prior Art Documents

[0007] Patent Documents

[0008] Patent Document 1: Japanese Patent Laid-Open No. 2013-023510

[0009] Patent Document 2: Japanese Patent Laid-Open No. 2017-075326 Summary of the Invention

[0010] Problems to be Solved by the Invention

[0011] In the invention of Patent Document 1, an improvement in flame retardancy due to urethane ester bonds was found. However, a large number of urethane bonds are formed, and it may not be possible to say that the flame retardancy is sufficient. In addition, the invention of Patent Document 2 describes that high flame retardancy is imparted by adding red phosphorus (powder) as a flame retardant and incorporating an isocyanurate ring. However, considering the use of a powder flame retardant, for example, poor adhesion (warpage) may occur with the adherend during spray coating, and over time, the foam material may fall off and the heat insulation performance may decrease. In Patent Document 2, this is not particularly mentioned. In addition, the inventions of Patent Document 1 and 2 have not verified any time-dependent deterioration caused by temperature and humidity, which is important when used as a heat insulation material or a thermal insulation material for building applications, oil and gas transportation ships, and electrical appliances such as refrigerators. There may be time-dependent deterioration in a humid and hot environment. In addition, when the inventions of Patent Document 1 and 2 are used, for example, in building applications, when in contact with a flame due to a fire or the like, cracks sometimes occur, or carbonization occurs inside the foam, and the strength is significantly reduced, which may lead to the collapse of the building, etc.

[0012] Accordingly, an object of the present invention is to provide a urea resin composition and a foam thereof that can provide a novel foam different from a urethane foam.

[0013] A second object of the present invention is to provide a urea resin composition and a foam thereof that can provide a polyurea foam having excellent flame retardancy and shape retention during combustion, can suppress time-dependent deterioration in a humid and hot environment, has excellent adhesiveness to an adherend during coating, is not likely to generate cracks even when in contact with a flame, and is not likely to have carbonization caused by contact with a flame proceed from the surface to the depth.

[0014] Means for Solving the Problems

[0015] The present inventors conducted in-depth research to achieve the above object and found that a polyurea foam formed by foaming a specific urea resin composition can solve the above problems, thereby completing the present invention. That is, the present invention is as follows.

[0016] The present invention (1) is a urea resin composition containing a polyisocyanate compound (A), a polyamine compound (B), a trimerization catalyst, a foaming agent, a foam stabilizer, and a flame retardant.

[0017] The present invention (2) is a polyurea foam containing a flame retardant and having an isocyanurate structure.

[0018] The present invention (3) is a urea resin composition which is a urea resin composition containing a polyisocyanate compound (A), a polyamine compound (B), a trimerization catalyst, a foaming agent, and a foam stabilizer, wherein no polyol compound is contained, or the content of the polyol compound is 1 / 5 or less by mass ratio with respect to the content of the above polyamine compound (B).

[0019] The present invention (4) is a composition for producing a polyurea foam, which contains a polyamine compound (B), a trimerization catalyst, a foaming agent, a foam stabilizer, and a flame retardant.

[0020] The present invention (5) is a composition for producing a polyurea foam, which is a composition for producing a polyurea foam containing a polyamine compound (B), a trimerization catalyst, a foaming agent, and a foam stabilizer, wherein no polyol compound is contained, or the content of the polyol compound is 1 / 5 or less by mass ratio with respect to the content of the above polyamine compound (B).

[0021] The present invention (6) is a urea resin composition which is a urea resin composition containing a polyisocyanate compound (A), a polyamine compound (B), a trimerization catalyst, a foaming agent, a foam stabilizer, and a flame retardant, wherein when the total amount of the above urea resin composition is set to 100% by mass, the content of the above polyamine compound (B) is 2.0% by mass or more, and when the content of the polyamine compound (B) in the above urea resin composition is set to 100 parts by mass, the content of the above trimerization catalyst is 5 to 20 parts by mass.

[0022] The present invention (7) is a polyurea foam obtained by foaming and curing the urea resin composition of the above invention (6).

[0023] The present invention (8) is a polyurea foam having an isocyanurate structure, characterized in that the isocyanuration rate of the above polyurea foam is 25 to 50%. It should be noted that the isocyanuration rate is a value calculated by the following formula (1) based on the absorption spectrum of the above polyurea foam obtained by infrared spectroscopic analysis.

[0024] (Formula 1)

[0025] Isocyanuration rate (%) = P1 / (P1 + P2 + P3 + P4) × 100

[0026] P1: Peak area derived from the isocyanurate structure contained in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis

[0027] P2: The peak area of C=O derived from the urea structure in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis

[0028] P3: The peak area of C=O derived from the carbamate structure and isocyanurate structure in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis

[0029] P4: The peak area of N-H contained in the carbamate structure and urea structure in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis

[0030] In addition, the present invention may also be the following inventions.

[0031] The present invention (9) is a polyurea foam having an isocyanurate structure and a 5% weight loss temperature of 175 °C or higher. It should be noted that the 5% weight loss temperature is to observe the weight loss behavior of the sample in the temperature range of 25 - 700 °C under a dry air stream at a heating rate of 10 °C / minute using a differential thermal / thermogravimetric synchronous analyzer, and measure the temperature at which the sample weight loss is 5% by weight.

[0032] The present invention (10) is a urea resin composition containing a polyisocyanate compound (A), a polyamine compound (B), a trimerization catalyst, a foaming agent, a foam stabilizer, and a flame retardant. The characteristic is that when the total amount of the above urea resin composition is set to 100% by mass, the content of the above polyamine compound (B) is 2.0% by mass or more.

[0033] The present invention (11) is the urea resin composition as described in the above invention (10), characterized in that the amine value of the above polyamine compound (B) is 50 - 1000 mg KOH / g.

[0034] The present invention (12) is the urea resin composition as described in the above invention (10) or (11), characterized in that the NCO% of the above polyisocyanate compound (A) is 10 - 35%.

[0035] The present invention (13) is the urea resin composition as described in any one of the above inventions (10) - (12), characterized in that the above polyisocyanate compound (A) is an aromatic isocyanate.

[0036] The present invention (14) is the urea resin composition as described in any one of the above inventions (10) - (13), characterized in that the above flame retardant contains red phosphorus.

[0037] The present invention (15) is a urea resin composition as described in any one of the above-mentioned inventions (10) to (14), characterized in that the flame retardant contains at least one selected from phosphate esters, phosphate-containing flame retardants, bromine-containing flame retardants, boron-containing flame retardants, antimony-containing flame retardants, and metal hydroxides.

[0038] The present invention (16) is a polyurea foam obtained by foaming and curing the urea resin composition as described in any one of the above-mentioned inventions (10) to (15).

[0039] The present invention (17) is a polyurea foam as described in the above-mentioned invention (16), characterized in that the total heat release amount after 20 minutes measured under the condition of heating with a radiant heat intensity of 50 kW / m 2 is 8.5 MJ / m 2 or less.

[0040] The present invention (18) is a polyurea foam having an isocyanurate structure.

[0041] The present invention (19) is a polyurea foam as described in the above-mentioned invention (18), characterized in that it contains a flame retardant.

[0042] The present invention (20) is a polyurea foam as described in the above-mentioned invention (18) or (19), characterized in that it contains red phosphorus.

[0043] The present invention (21) is a polyurea foam as described in the above-mentioned invention (20), characterized in that when the total mass of the polyurea foam is set to 100% by mass, the content of the red phosphorus is 1 to 30% by mass.

[0044] The present invention (22) is a polyurea foam as described in any one of the above-mentioned inventions (18) to (21), characterized in that the isocyanuration rate of the polyurea foam is 10 to 50%. It should be noted that the isocyanuration rate is a value calculated by the following formula (1) based on the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis.

[0045] (Formula 1)

[0046] Isocyanuration rate (%) = P1 / (P1 + P2 + P3 + P4) × 100

[0047] P1: The peak area derived from the isocyanurate structure contained in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis

[0048] P2: The peak area of C=O derived from the urea structure contained in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis

[0049] P3: The peak area of C=O derived from the urethane structure and the isocyanurate structure in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis

[0050] P4: The peak area of N-H contained in the urethane structure and the urea structure in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis

[0051] The polyurea foam of the present invention (23) is the polyurea foam according to any one of the above-mentioned inventions (18) to (22), and is characterized by containing at least one selected from phosphate esters, phosphate-containing flame retardants, bromine-containing flame retardants, boron-containing flame retardants, antimony-containing flame retardants, and metal hydroxides.

[0052] Advantages of the Invention

[0053] According to the present invention, it is possible to provide a urea resin composition and a foam thereof that can provide a new foam different from urethane foams.

[0054] In addition, according to the present invention, it is possible to provide a urea resin composition and a foam thereof that can provide a foam having sufficient flame retardancy and compression properties.

[0055] Furthermore, according to the present invention, it is possible to provide a urea resin composition and a foam thereof that can provide a polyurea foam having excellent flame retardancy and shape retention during combustion, capable of suppressing deterioration over time in a humid and hot environment, having excellent adhesiveness to an adherend during coating, not easily generating cracks even when in contact with a flame, and not easily allowing carbonization caused by contact with a flame to proceed from the surface to the depth. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 is an explanatory diagram for explaining a mold for forming the polyurea foam for observing the shape and average bubble diameter of bubbles (cells) of the present invention and the flow direction of the foam. DETAILED DESCRIPTION OF THE INVENTION

[0057] 1. Urea Resin Composition

[0058] The polyurea foam of the present invention has an isocyanurate structure. In addition, the polyurea foam is obtained by foaming and curing a urea resin composition. The urea resin composition of the present invention is a urea resin composition containing a polyisocyanate compound (A), a polyamine compound (B), a trimerization catalyst, a foaming agent, and preferably a foam stabilizer and a flame retardant. In the following description, when upper and lower limits are separately described, the upper and lower limits can be freely combined to form a new numerical range.

[0059] The urea resin composition of the present invention is characterized in that when the total amount of the above urea resin composition is set to 100% by mass, the content of the polyamine compound (B) is 2.0% by mass or more.

[0060] The urea resin composition of the present invention can form a polyurea foam by foaming and curing.

[0061] 2. Raw materials of the urea resin composition

[0062] 2-1. Polyisocyanate compound (A)

[0063] The polyisocyanate compound (A) of the present invention is not particularly limited as long as it does not hinder the effects of the present invention. Examples of the polyisocyanate compound (A) include monomeric polyisocyanates and polymeric polyisocyanates. Monomeric polyisocyanates refer to compounds having two or more isocyanate groups at the ends of the monomer structure. Polymeric polyisocyanates refer to compounds having two or more isocyanate groups at the ends of the polymer structure. These polyisocyanate compounds (A) can be used alone or in combination of multiple types.

[0064] Regarding monomeric polyisocyanates, for example, as bifunctional polyisocyanate compounds, there can be mentioned: 2,4-toluene diisocyanate (2,4-TDI), 2,6-toluene diisocyanate (2,6-TDI), m-phenylene diisocyanate, p-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate (4,4'-MDI), 2,4'-diphenylmethane diisocyanate (2,4'-MDI), 2,2'-diphenylmethane diisocyanate (2,2'-MDI), hydrogenated MDI, xylylene diisocyanate, 3,3'-dimethyl-4,4'-biphenyl diisocyanate, 3,3'-dimethoxy-4,4'-biphenyl diisocyanate, polymethylene polyphenyl polyisocyanate, 1,5-naphthalene diisocyanate, xylylene diisocyanate (XDI), hydrogenated XDI, tetramethylxylylene diisocyanate (TMXDI) and other aromatic polyisocyanate compounds; cyclohexane-1,4-diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, methylcyclohexane diisocyanate and other alicyclic polyisocyanate compounds; butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, lysine diisocyanate and other alkylene polyisocyanate compounds;

[0065] Examples of polyisocyanates having three or more functional groups include 1-methylbenzene-2,4,6-triisocyanate, 1,3,5-trimethylbenzene-2,4,6-triisocyanate, biphenyl-2,4,4'-triisocyanate, diphenylmethane-2,4,4'-triisocyanate, methyldiphenylmethane-4,6,4'-triisocyanate, 4,4'-dimethyldiphenylmethane-2,2',5,5'-tetraisocyanate, triphenylmethane-4,4',4''-triisocyanate, polymeric MDI, lysine ester triisocyanate, 1,3,6-hexamethylene triisocyanate, 1,6,11-undecane triisocyanate, bicycloheptane triisocyanate, 1,8-diisocyanatomethyloctane, etc.;

[0066] In addition, modified products, derivatives, etc. thereof may be included. Examples of their modified products and derivatives include isocyanurate compounds of diisocyanate compounds, addition compounds of diisocyanate compounds, biuret compounds of diisocyanate compounds, urethane-formate compounds of diisocyanate compounds, and carbodiimide-modified compounds of diisocyanate compounds.

[0067] It should be noted that these polyisocyanate compounds can be used alone or in combination of multiple kinds.

[0068] The monomeric polyisocyanate compound forms the urea skeleton of the polyurea foam, so it can be freely selected in consideration of the desired characteristics of the polyurea foam. Among these monomeric polyisocyanates, from the aspect of excellent reactivity, aromatic isocyanates are preferred, more preferably MDI, or modified products or derivatives of MDI, and further preferably monomeric MDI and crude MDI. These preferred aromatic isocyanates have excellent reactivity when used as polyurea foams for spraying processes, and thus are preferred in terms of the safety of the working environment. In addition, among monomeric MDI and crude MDI having the same NCO%, the isocyanuration rate of the crude MDI containing polynuclear bodies is excellent, and thus the flame retardancy is excellent.

[0069] Examples of the polymeric polyisocyanate compound include substances prepolymerized by reacting an active hydrogen compound having two or more active hydrogen groups, such as a polyol compound or a polyamine compound (D), with an excessive amount of a polyisocyanate compound (C). It should be noted that the polyamine compound (D) and the polyisocyanate compound (C) are raw materials for producing the polymeric polyisocyanate, and are not included in the polyamine compound (B) and the polyisocyanate compound (A) which are raw materials of the urea resin composition in the present invention. Here, the polyisocyanate compound (C) may be the same as or different from the polyisocyanate compound (A).

[0070] Examples of such polyol compounds include polyester polyols and polyether polyols. Examples of polyester polyols include those obtained by the condensation reaction of polyols and polycarboxylic acids. Examples of polyols include ethylene glycol, propylene glycol, butanediol, butylene glycol, glycerin, trimethylolpropane, etc. Examples of polycarboxylic acids include glutaric acid, adipic acid, maleic acid, phthalic acid, terephthalic acid, isophthalic acid, etc. They can be used alone or in combination of multiple kinds. In addition, polyester polyols obtained by ring-opening condensation of caprolactone, methylvalerolactone, etc. can be cited.

[0071] Examples of polyether polyols include substances obtained by addition polymerization of oxides such as ethylene oxide, propylene oxide, trimethylene oxide, and butylene oxide to polyols such as ethylene glycol, propylene glycol, diethylene glycol, glycerin, trimethylolpropane, and sorbitol. They can be used alone or in combination of multiple kinds.

[0072] Examples of the polyisocyanate compound (B) that reacts with these polyol compounds are not particularly limited as long as the effects of the present invention are not hindered, and include aliphatic or aromatic polyisocyanates, mixtures thereof, and modified polyisocyanates obtained by modifying them.

[0073] Examples of the polyamine compound (D) are not particularly limited as long as the effects of the present invention are not hindered. Examples of the polyamine compound (D) include aliphatic polyamines such as triethylenetetramine, aromatic polyamines such as m-phenylenediamine, and alicyclic polyamines such as isophoronediamine. Specifically, 4,4'-diamino-3,3'-dichlorodiphenylmethane, trimethylene-bis(4-aminobenzoate), 4,4'-diamino-3,3'-diethyl-5,5'-dimethyl-diphenylmethane, polytetrahydrofuran-bis(p-aminobenzoate), 2,2',6,6'-tetraethyl-4,4'-methylenedianiline, 4,4'-methylenebis(2-isopropyl-6-methylaniline), 4,4'-methylenebis(2,6-diisopropylaniline), 4,4'-methylenebis(3-chloro-2,6-diethylaniline), 3,5-diethyltoluene-2,4-diamine, and dimethylthiotoluenediamine can be cited.

[0074] They can be used alone or in combination of multiple kinds. In addition, the polyamine compound (D) can be the same as or different from the polyamine compound (B) described later.

[0075] The NCO% of the polyisocyanate compound (A) is not limited as long as the effects of the present invention are not hindered. For example, it can be set to 5 to 40%, preferably 10 to 35%, more preferably 15 to 35%. If the NCO% of the polyisocyanate compound (A) increases, a polyurea foam with high shape retention during combustion, low thermal conductivity, and capable of suppressing deterioration over time in a humid and hot environment can be obtained. That is, a polyurea foam with excellent flame retardancy and shape retention during combustion, capable of suppressing deterioration over time in a humid and hot environment, and excellent in adhesiveness to the adherend during coating can be obtained.

[0076] The NCO% (isocyanate content) of the polyisocyanate compound (A) is measured according to Method A (toluene / dibutylamine, hydrochloric acid method) of JIS K1603-1:2007 "Plastics - Polyurethane raw materials - Aromatic isocyanates - Test methods - Part 1: Method for determining the isocyanate group content".

[0077] 2-2. Polyamine compound (B)

[0078] The polyamine compound forms a urea bond by reacting with isocyanate. The urea bond has excellent characteristics such as water resistance, corrosion resistance, acid resistance, and alkali resistance.

[0079] The polyamine compound (B) is not particularly limited as long as it does not hinder the effects of the present invention. Examples of the polyamine compound (B) include aliphatic polyamines such as triethylenetetramine, aromatic polyamines such as m-phenylenediamine, and alicyclic polyamines such as isophoronediamine. Specifically, examples include: 4,4'-diamino-3,3'-dichlorodiphenylmethane, trimethylene-bis(4-aminobenzoate), 4,4'-diamino-3,3'-diethyl-5,5'-dimethyl-diphenylmethane, polytetrahydrofuran-bis(p-aminobenzoate), 2,2',6,6'-tetraethyl-4,4'-methylenedianiline, 4,4'-methylenebis(2-isopropyl-6-methylaniline), 4,4'-methylenebis(2,6-diisopropylaniline), 4,4'-methylenebis(3-chloro-2,6-diethylaniline), 3,5-diethyltoluene-2,4-diamine, dimethylthiotoluenediamine. Examples of commercially available products include: IHARACUAMINE MT, IHARACUAMINE M liquid product, CUA-4, CUREHARDMED, ELASMER 250P, ELASMER 1000P manufactured by KUMIAI Chemical Industry Co., Ltd.; Lonzacure M-DEA, Lonzacure M-MIPA, Lonzacure M-DIPA, Lonzacure M-CDEA manufactured by Lonza Japan Co., Ltd.; ETHACURE 100, ETHACURE 300, ETHACURE 410, ETHACURE 420 manufactured by Albemarle Corporation; VERSALINK 740 manufactured by Evonik Nutrition & Care GmbH; ANCAMINE 2049 manufactured by Evonik Corporation. They can be used alone or in combination of multiple kinds.

[0080] The amine value of the polyamine compound (B) is not particularly limited as long as it does not hinder the effects of the present invention. For example, it can be set to 50 to 1000 mgKOH / g, preferably 200 to 1000 mgKOH / g, more preferably 450 to 1000 mgKOH / g, and still more preferably 500 to 1000 mgKOH / g. When the amine value of the polyamine compound is within this range, a urea resin composition for a polyurea foam can be obtained, which can provide excellent flame retardancy and shape retention during combustion, can suppress deterioration over time in a humid and hot environment, has excellent adhesiveness to an adherend during coating, is not likely to crack even when in contact with a flame, and the carbonization caused by contact with the flame is not likely to proceed from the surface to the deep part. In particular, in the total heat release test (a test indicating flame retardancy, hereinafter sometimes simply referred to as the cone calorimeter total heat release test), the volume change rate at 600 °C (a test indicating shape retention), and the flame contact test according to the ISO-5660 standard described below, a carbonized layer is formed on the surface of the foam, and excellent effects are shown in terms of preventing fire from penetrating into the deep part of the foam.

[0081] The amine value of the polyamine compound (B) can be measured by the method for measuring the total amine value described in JIS K1557-7:2011 "Plastics - Test Methods for Polyol Raw Materials for Polyurethanes - Part 7: Method for Determining Alkalinity (Expressed as Nitrogen Content and Total Amine Value)".

[0082] In addition to the polyamine compound (B) of the present invention, an active hydrogen compound can be added as long as it does not hinder the effects of the present invention. Examples of the active hydrogen compound include alcohols such as primary alcohols, secondary alcohols, and tertiary alcohols, monohydric alcohol, polyhydric alcohol compounds, or thiol compounds. The alcohols and polyhydric alcohol compounds can react with the polyisocyanate compound (A) to form a urethane bond and form a part of the skeleton of the polyurea foam. However, since the combustibility of the urethane bond is higher than that of the urea bond, the flame retardancy of the polyurea foam may be reduced. Therefore, the content of the polyhydric alcohol compound can be set to 1 / 5 or less, preferably 1 / 10 or less, more preferably no polyhydric alcohol compound, based on the mass ratio with respect to the content of the polyamine compound (B).

[0083] 2-3. Trimerization catalyst

[0084] The trimerization catalyst of the present invention is not particularly limited as long as it does not hinder the effects of the present invention. By using the trimerization catalyst, an isocyanurate structure can be formed in the polyurea foam when manufacturing the polyurea foam using the polyamine compound (B). Examples of the trimerization catalyst include: metal oxides such as lithium oxide, sodium oxide, and potassium oxide; alcohol salts such as sodium methoxide, sodium ethoxide, sodium propoxide, sodium butoxide, potassium methoxide, potassium ethoxide, potassium propoxide, and potassium butoxide; organic metal salts such as potassium acetate, potassium octoate, potassium caprylate, and iron oxalate; tertiary amines such as 2,4,6-tris(dimethylaminomethyl)phenol, N,N',N''-tris(dimethylaminopropyl)hexahydrotriazine, triethylenediamine, and 1,3,5-tris(dimethylaminopropyl)hexahydro-s-triazine; derivatives of ethyleneimine; chelate compounds of acetylacetone of alkali metals, aluminum, and transition metals; quaternary ammonium salts; diazabicycloundecene (DBU), etc.

[0085] They can be used alone or in combination of multiple kinds. Among them, it is more preferable to use tertiary amines, organic metal salts, and diazabicycloundecene, and it is more preferable to use tertiary amines and diazabicycloundecene. By using these preferable trimerization catalysts, a polyurea foam with excellent flame retardancy and shape retention during combustion, capable of suppressing deterioration over time in a humid and hot environment, and having excellent adhesiveness to the adherend during coating can be obtained.

[0086] 2-4. Blowing agent

[0087] The blowing agent of the present invention is not particularly limited as long as it does not hinder the effects of the present invention. Examples of the blowing agent include water, hydrocarbons (preferably C4 - C6), hydrofluoroolefins, and carbon dioxide. Specifically, cyclopentane, HFO(1336mzz), and HFO(1233zd) can be cited. They can be used alone or in combination of multiple kinds.

[0088] 2-5. Foam stabilizer

[0089] The foam stabilizer of the present invention is not particularly limited as long as it does not hinder the effects of the present invention. Examples of the foam stabilizer include silicone compounds, nonionic surfactants, etc. They can be used alone or in combination of multiple kinds.

[0090] 2-6. Flame retardant

[0091] The urea resin composition of the present invention may contain a flame retardant. As the flame retardant, there is no particular limitation as long as the effects of the present invention are not hindered. For example, red phosphorus, phosphate esters, phosphate-containing flame retardants, bromine-containing flame retardants, boron-containing flame retardants, antimony-containing flame retardants, and metal hydroxides can be cited. They can be used alone or in combination of multiple kinds. Among these, it is preferred to contain at least one selected from red phosphorus or phosphate esters, phosphate-containing flame retardants, bromine-containing flame retardants, boron-containing flame retardants, antimony-containing flame retardants, and metal hydroxides. More preferably, it contains red phosphorus. Further preferably, in addition to red phosphorus, it also contains at least one selected from phosphate esters, phosphate-containing flame retardants, bromine-containing flame retardants, boron-containing flame retardants, antimony-containing flame retardants, and metal hydroxides. Particularly preferably, it contains red phosphorus and phosphate esters and also contains at least one selected from chlorine-containing phosphate esters, phosphate-containing flame retardants, bromine-containing flame retardants, boron-containing flame retardants, antimony-containing flame retardants, and metal hydroxides. Particularly preferably, it contains red phosphorus, phosphate esters, and bromine-containing flame retardants. When the urea resin composition of the present invention contains these flame retardants, a polyurea foam having excellent flame retardancy and shape retention during combustion, capable of suppressing deterioration over time in a humid and hot environment, and having excellent adhesiveness to an adherend during coating can be obtained. In addition, other flame retardants other than these can be contained.

[0092] The phosphate ester of the present invention is not particularly limited as long as the effects of the present invention are not hindered. As the phosphate ester, for example, aromatic phosphate esters such as triphenyl phosphate, tolyldiphenyl phosphate, tricresyl phosphate, tris(xylenyl) phosphate, tris(tert-butylated phenyl) phosphate, tris(isopropylphenyl) phosphate, and 2-ethylhexyl diphenyl phosphate can be cited; aromatic condensed phosphate esters such as 1,3-phenylene bis(diphenyl phosphate), 1,3-phenylene bis(xylenyl) phosphate, resorcinol bis(diphenyl) phosphate, and bisphenol A bis(diphenyl phosphate); halogen-containing phosphate esters such as tris(dichloropropyl) phosphate, tris(β-chloropropyl) phosphate, and tris(chloroethyl) phosphate; halogen-containing condensed phosphate esters such as 2,2-bis(chloromethyl)trimethylene bis(bis(2-chloroethyl) phosphate) and polyoxyalkylene bisdichloroalkyl phosphate; etc. They can be used alone or in combination of multiple kinds.

[0093] The phosphate-containing flame retardants of the present invention are not particularly limited as long as they do not hinder the effects of the present invention. As phosphate-containing flame retardants, for example, as monophosphates, ammonium salts such as ammonium phosphate, ammonium dihydrogen phosphate, and diammonium hydrogen phosphate can be listed; sodium salts such as sodium dihydrogen phosphate, disodium hydrogen phosphate, trisodium phosphate, sodium hypophosphite, sodium phosphite, and sodium phosphite; potassium salts such as potassium dihydrogen phosphate, dipotassium hydrogen phosphate, tripotassium phosphate, potassium hypophosphite, potassium phosphite, and potassium phosphite; lithium salts such as lithium dihydrogen phosphate, dilithium hydrogen phosphate, trilithium phosphate, lithium hypophosphite, lithium phosphite, and lithium phosphite; barium salts such as barium dihydrogen phosphate, barium hydrogen phosphate, tribarium phosphate, and barium hypophosphite; magnesium salts such as magnesium hydrogen phosphate, magnesium hydrogen phosphate, trimagnesium phosphate, and magnesium hypophosphite; calcium salts such as calcium dihydrogen phosphate, calcium hydrogen phosphate, tricalcium phosphate, and calcium hypophosphite; zinc salts such as zinc phosphate, zinc phosphite, and zinc hypophosphite; aluminum salts such as primary aluminum phosphate, secondary aluminum phosphate, tertiary aluminum phosphate, aluminum phosphite, and aluminum hypophosphite; etc.

[0094] As polyphosphates, for example, ammonium polyphosphate, piperazine polyphosphate, melamine polyphosphate, ammonium polyphosphate amide, aluminum polyphosphate, etc. can be listed. They can be used alone or in combination of multiple kinds.

[0095] The bromine-containing flame retardants of the present invention are not particularly limited as long as they do not hinder the effects of the present invention. As bromine-containing flame retardants, for example, pentabromodiphenyl ether; octabromodiphenyl ether; decabromodiphenyl ether; tetrabromobisphenol A (TBBA), TBBA-epoxy oligomer, TBBA-polycarbonate oligomer, TBBA-bis(dibromopropyl ether), TBBA-bis(aryl ether) and other TBBA compounds; polyphenyl ring compounds such as diphenyl pentamethane, 1,2-bis(2,4,6-tribromophenoxy)ethane, 2,4,6-tris(2,4,6-tribromophenoxy)-1,3,5-triazine, 2,6-dibromophenol, 2,4-dibromophenol, etc.; brominated styrene compounds such as brominated polystyrene, polybrominated styrene; phthalic acid compounds such as ethylenebis(tetrabromophthalimide); cyclic aliphatic compounds such as hexabromocyclododecane; polybrominated aromatic acrylate compounds such as poly(pentabromophenyl acrylate); etc. They can be used alone or in combination of multiple kinds.

[0096] The boron-containing flame retardants of the present invention are not particularly limited as long as they do not hinder the effects of the present invention. As boron-containing flame retardants, for example, borax; boron oxides such as boron trioxide, boron oxide, diboron dioxide, tetraboron trioxide, tetraboron pentoxide; boric acid compounds such as boric acid, lithium borate, sodium borate, potassium borate, cesium borate, magnesium borate, calcium borate, barium borate, zirconium borate, zinc borate, aluminum borate, ammonium borate, etc.

[0097] The antimony-containing flame retardant of the present invention is not particularly limited as long as it does not hinder the effects of the present invention. Examples of the boron-containing flame retardant include, for example, antimony oxides such as antimony trioxide and antimony pentoxide; antimonates such as sodium antimonate and potassium antimonate; pyroantimonates such as sodium pyroantimonate and potassium pyroantimonate; and the like. They can be used alone or in combination of multiple kinds.

[0098] The metal hydroxide of the present invention is not particularly limited as long as it does not hinder the effects of the present invention. Examples of the metal hydroxide include, for example, aluminum hydroxide, magnesium hydroxide, and the like. They can be used alone or in combination of multiple kinds.

[0099] As other flame retardants, known flame retardants can be used. Examples of other flame retardants include, for example, chlorine compounds such as chlorinated paraffin; nitrogen compounds such as hindered amines and melamine cyanurate; cellulose; and the like. They can be used alone or in combination of multiple kinds.

[0100] 2-7. Other Additives

[0101] In the resin composition of the present invention, as long as the effects of the present invention are not hindered, other additives can be added in addition to the above-mentioned additives. As other additives, additives known as additives such as resin (urea) catalysts, foaming catalysts, equilibrium catalysts, antioxidants, ultraviolet absorbers, antibacterial agents, and dispersants can be added.

[0102] 3. Characteristics of the Urea Resin Composition

[0103] The cream time of the urea resin composition of the present invention at 5°C can be set to 1 to 120 seconds, preferably 2 to 70 seconds. When the cream time of the urea resin composition at 5°C is within this range, a more excellent effect is exerted in terms of sufficiently obtaining the fluidity of the liquid and the wettability / adhesiveness to the body. Here, the cream time refers to the time from the moment when a mixture (hereinafter sometimes referred to as a composition for producing a polyurea foam) obtained by mixing all other compositions except the polyisocyanate compound (A) in the urea resin composition and the polyisocyanate compound (A) is mixed until these mixtures start to foam and become a milky liquid before starting to expand. The start time is determined by visually observing the color change of the solution of the mixture. It should be noted that 5°C means that the polyisocyanate compound (A) and the composition for producing a polyurea foam are each maintained at 5°C and mixed.

[0104] The cream time of the urea composition of the present invention at 20°C can be set to 0.5 to 90 seconds, preferably 0.7 to 60 seconds. When the cream time of the urea resin composition at 20°C is within this range, it exhibits a more excellent effect in terms of the liquid thickening before the foaming agent volatilizes at the practical liquid temperature and efficient foaming without cell collapse. In the method for measuring the cream time at 5°C, except for mixing the polyisocyanate compound (A) and the composition for producing a polyurea foam while maintaining them at 20°C respectively, the cream time of the urea composition at 20°C is measured by the same measurement method.

[0105] 4. Characteristics of the polyurea foam

[0106] 4-1. Isocyanurate conversion rate

[0107] The polyurea foam of the present invention contains an isocyanurate structure. The isocyanurate structure is formed by trimerizing the polyisocyanate compound (A) which is a raw material of the urea resin composition by using a trimerization catalyst. The isocyanurate structure can be detected by infrared spectroscopic analysis. The ratio of the polyisocyanate compound (A) that is isocyanurated (isocyanurate conversion rate) is calculated by the following formula (1) based on the absorption spectrum obtained by infrared spectroscopic analysis. The isocyanurate conversion rate is not particularly limited as long as it does not hinder the effects of the present invention. For example, it can be set to 10 to 50%, preferably 20 to 45%, more preferably 25 to 40%. In addition, the lower limit value can be set to 10% or more, 20% or more, 25% or more, 28% or more, and the upper limit value can be set to 50% or less, 45% or less, 43% or less, 40% or less. If the isocyanurate conversion rate is within this range, the polyurea foam has excellent flame retardancy.

[0108] (Formula 1)

[0109] Isocyanurate conversion rate (%) = P1 / (P1 + P2 + P3 + P4) × 100

[0110] P1: The peak area derived from the isocyanurate structure contained in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis

[0111] P2: The peak area of C=O derived from the urea structure contained in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis

[0112] P3: The peak area of C=O derived from the urethane structure and the isocyanurate structure contained in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis

[0113] P4: The peak area of N-H contained in the urethane structure and the urea structure derived from the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis

[0114] P1 is the area of the peak derived from the isocyanurate structure contained in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis, and is the area of the peak derived from the isocyanurate ring near a wave number of 1410 cm -1 The peak area near the isocyanurate ring. P1 is the peak area in the range of wave numbers from 1380 to 1430 cm -1 The range of peak areas. P1 represents the content of the isocyanurate structure formed by the reaction of the isocyanate groups of the raw material polyisocyanate compound (A).

[0115] P2 is the peak area of C=O derived from the urea structure contained in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis, and is the area of the peak of C=O derived from the urea bond near a wave number of 1595 cm -1 The peak area near the urea bond. P2 is the peak area in the range of wave numbers from 1550 to 1640 cm -1 The range of peak areas. P2 represents the content of the urea structure formed by the reaction of the isocyanate groups of the raw material polyisocyanate compound (A).

[0116] P3 is the peak area of C=O derived from the urethane structure and the isocyanurate structure contained in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis, and is the area of the peak of the C=O bond near a wave number of 1710 cm -1 The peak area near the C=O bond. P3 is the peak area in the range of wave numbers from 1680 to 1730 cm -1 The range of peak areas. P3 represents the content of the urethane structure and the isocyanurate structure formed by the reaction of the isocyanate groups of the raw material polyisocyanate compound (A).

[0117] P4 is the peak area of N-H contained in the urethane structure and the urea structure in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis, and is the area of the peak of N-H near a wave number of 1510 cm -1 The peak area near the N-H. P4 is the peak area in the range of wave numbers from 1470 to 1550 cm -1 The range of peak areas. P4 represents the content of the urethane structure and the urea structure contained in the polyurea foam, and represents the content of the urethane structure and the urea structure formed by the reaction of the isocyanate groups of the raw material polyisocyanate compound (A).

[0118] Therefore, the sum of P1 to P4 represents the total number of reactions of the isocyanate groups of the polyisocyanate compound (A) as the raw material. Therefore, the isocyanuration rate is the value representing the proportion of the isocyanate groups of the polyisocyanate compound (A) as the raw material that become the isocyanurate structure in the reaction.

[0119] 4-2. Density

[0120] The density of the polyurea foam is not particularly limited as long as it does not hinder the effects of the present invention, and can be set to 10 to 200 kg / m 3 、preferably 10 to 100 kg / m 3 、more preferably 10 to 55 kg / m 3 。When the density of the polyurea foam is within this range, a polyurea foam with excellent thermal conductivity and excellent flame retardancy can be obtained. The density of the polyurea foam is measured in accordance with JIS K7222:2005 "Foamed Plastics and Rubbers - Method for Determination of Apparent Density".

[0121] 4-3. Average cell (bubble) diameter and cell shape

[0122] Regarding the average cell diameter and shape of the bubbles (cells) contained in the polyurea foam, the following test pieces are prepared and observed and measured using an optical microscope with a length measurement function (for example, a digital microscope). The test pieces are prepared as follows: The urea resin composition is poured into a box-shaped mold (for example, a mold for forming a foam into a rectangular parallelepiped shape), foamed and cured to obtain a formed polyurea foam, and a test piece with a length of 50 mm × width of 50 mm × thickness of 20 mm is cut out from the polyurea foam. Here, it is taken out in such a way that the foaming flow direction (the direction in which the urea resin composition foams and expands, the direction vertically above the bottom surface of the mold. Hereinafter, this direction will be referred to as the upward direction) during foaming in the mold is the thickness direction of the test piece. The surface with the upward direction of the taken-out test piece as the normal line is defined as the CD surface. In addition, the surface orthogonal to the CD surface of the test piece is defined as the MD surface. The CD surface is observed with an optical microscope (including a digital microscope) to determine its shape. At this time, 10 bubbles on the CD surface are randomly selected, and the difference (DR = R1 - R2) between the longest diameter (designated as R1) in the CD surface of each bubble and the diameter (designated as R2) in the direction orthogonal to the longest diameter is calculated. The case where the average value of DR of all the selected bubbles exceeds 5 mm is judged as elliptical.

[0123] In addition, 0 mm or more and 5 mm or less is judged as circular.

[0124] In addition, 10 bubbles in the CD surface and 10 bubbles in the MD surface are randomly selected respectively, and the length of their major axes is measured, and the averaged values are used as the average cell diameter in the CD surface and the average cell diameter in the CD surface. In addition, the ratio of the average cell diameter in the MD surface to the average cell diameter in the CD surface (average cell diameter in the MD surface / average cell diameter in the CD surface) can be set to 0.7 to 1.8, preferably 0.8 to 1.3. When these values are within this range, a polyurea foam with excellent performance can be obtained.

[0125] 4-4. Independent bubble ratio

[0126] The air bubbles contained in the polyurea foam are not particularly limited as long as they do not hinder the effects of the present invention, and may include any one of closed cells, open cells, and semi-open cells. Here, the semi-open cell structure refers to a structure different from closed cells, having small pores in the bubbles, and refers to a structure in which the pores of adjacent bubbles are smaller than those of the open cell structure.

[0127] The closed cell ratio of the polyurea foam can be set, for example, to 75% or more, preferably 80% or more. When the closed cell ratio is in this range, a polyurea foam with excellent properties can be obtained.

[0128] It should be noted that the closed cell ratio is calculated by the following method. The polyurea foam is processed into a test piece with a length of 30 mm × width of 30 mm × thickness of 20 mm, and the lengths of each side are accurately measured to calculate the apparent volume (V) of the test piece. The mass (W) of the test piece is measured. Using a dry-type automatic densitometer, the actual volume (V1) of the test piece is measured. The value calculated by the following formulas 2 to 4 is used as the closed cell ratio. It should be noted that each measurement is carried out in an environment with a temperature of 23 ± 5°C and a relative humidity of 40 to 70%.

[0129] (Formula 2)

[0130] Open cell ratio (%): Oc = (V - V1) / V × 100

[0131] (Formula 3)

[0132] Resin content of polyurea foam: S = W / (V × D) × 100

[0133] D is the density of the resin of the polyurea foam itself.

[0134] (Formula 4)

[0135] Closed cell ratio: Cc = 100 - Oc - S

[0136] 4 - 5.5% weight loss temperature

[0137] The 5% weight loss temperature of the polyurea foam can be set, for example, to 120 to 320°C, preferably 150 to 280°C. When the 5% weight loss temperature is in this range, a polyurea foam having the effects of the present invention can be obtained. Regarding the measurement of the 5% weight loss temperature, using a differential thermal / thermogravimetric synchronous measuring instrument (TG / DTA), the weight loss behavior of the polyurea foam is observed in the temperature range of 25 to 700°C, and the temperature at which the sample weight loss is 5% by weight is measured. The measurement is carried out with a heating rate set to 10°C / min under a dry air flow (flow rate: 250 mm / min).

[0138] 4 - 6. Measurement of ash content (at 600°C and 700°C)

[0139] The ash content of the polyurea foam when heated to 600°C can be set, for example, to 5 to 60% by weight, preferably 10% by weight or more. In addition, the ash content of the polyurea foam when heated to 700°C can be set, for example, to 3% by weight or more, preferably 5% by weight or more. When these values are within this range, a polyurea foam having the effects of the present invention can be obtained. Regarding the ash content when heated to 600°C and 700°C, using a differential thermal / thermogravimetric synchronous analyzer (TG / DTA), for the temperature range of 25 to 600°C or 25 to 700°C, the weight reduction behavior of the polyurea foam is observed, and the residual weight of the polyurea foam at 600°C or 700°C is measured and divided by the weight of the initial polyurea foam to obtain the ash content (% by weight) at 600°C or 700°C. The measurement is carried out under a dry air flow (flow rate: 250 mm / min) with a heating rate of 10°C / min.

[0140] 4 - 7. Retention amount (300°C × 30 minutes, 500°C × 30 minutes)

[0141] The retention amount of the polyurea foam after heat treatment at 300°C for 30 minutes can be set, for example, to 30 to 95% by weight, preferably 55 to 95% by weight. In addition, the retention amount of the polyurea foam after heat treatment at 500°C for 30 minutes can be set, for example, to 15 to 65% by weight, preferably 25 to 65% by weight. When these values are within this range, a polyurea foam having the effects of the present invention can be obtained. Regarding the retention amount when heated at 300°C and 500°C for 30 minutes, using a differential thermal / thermogravimetric synchronous analyzer (TG / DTA), the remaining weight of the polyurea foam after heating to 300°C or 500°C and then holding for 30 minutes is measured and divided by the weight of the initial polyurea foam to obtain the retention weight (% by weight). The measurement is carried out by heating to the specified temperature at a heating rate of 10°C / min, holding, and under a dry air flow (flow rate: 250 mm / min).

[0142] 4 - 8. Compressive strength

[0143] The compressive strength of the polyurea foam can be set, for example, to 300 to 800 kPa, preferably 350 to 800 kPa. When the compressive strength is within this range, a polyurea foam having the effects of the present invention can be obtained. The compressive strength is measured by the method described in JIS K7220:2006 "Rigid cellular plastics - Determination of compressive properties".

[0144] 4 - 9. Adhesive strength

[0145] The adhesive strength of the polyurea foam to the wooden board can be set, for example, to 50 to 250 kPa, preferably 70 to 250 kPa. When the adhesive strength is within this range, a polyurea foam having the effects of the present invention can be obtained. The adhesive strength is measured by the method described in JIS A9526:2015 "Sprayed rigid urethane foam for building insulation".

[0146] 4-10. Thermal conductivity

[0147] The thermal conductivity of the polyurea foam is not particularly limited as long as it does not hinder the effects of the present invention. For example, it can be set to 0.015 to 0.040 W / (m·K), preferably 0.015 to 0.026 W / (m·K). When the thermal conductivity is within this range, a polyurea foam having the effects of the present invention can be obtained. The thermal conductivity is measured by the method described in JIS A1412-1 "Method for measuring thermal resistance and thermal conductivity of thermal insulation materials - Part 1: Guarded hot plate method (GHP method)".

[0148] 4-11. Compressive elastic modulus

[0149] The compressive elastic modulus of the polyurea foam can be set, for example, to 8 to 30 MPa, preferably 10 to 30 MPa. When the compressive elastic modulus is within this range, a polyurea foam having the effects of the present invention can be obtained. The compressive elastic modulus is measured by the method described in JIS K7220:2006 "Rigid cellular plastics - Method for determining compressive properties".

[0150] 4-12. Water vapor transmission coefficient (water vapor permeability)

[0151] The water vapor transmission coefficient of the polyurea foam can be set, for example, to 2.5 to 9.5 ng / (m 2 ·s·Pa), preferably 2.5 to 8.5 ng / (m 2 ·s·Pa). When the water vapor transmission coefficient is within this range, a polyurea foam having the effects of the present invention can be obtained. The transmission coefficient is measured by the method described in JIS K7225:2018 "Rigid cellular plastics - Method for determining water vapor permeability".

[0152] 4-13. Tensile strength

[0153] The tensile strength of the polyurea foam can be set, for example, to 0.5 to 2.0 MPa, preferably 0.6 to 2.0 MPa. When the tensile strength is within this range, a polyurea foam having the effects of the present invention can be obtained. The tensile strength is measured by the method described in JISA9511:2017 "Foamed plastic thermal insulation materials".

[0154] 4-14. Tensile elongation at break

[0155] The tensile elongation at break of the polyurea foam can be set, for example, to 45 to 220%, preferably 55 to 180%. When the tensile elongation at break is within this range, a polyurea foam having the effects of the present invention can be obtained. Regarding the tensile elongation at break, test pieces are prepared according to the description in JIS A9511:2017 "Foamed Plastics Thermal Insulation Materials". Two marks with a spacing of 50 mm in the tensile direction are drawn in parallel. For this test piece, using a materials testing machine, a test is carried out at a tensile speed of 500 mm / minute, and the spacing between the above-mentioned marks until fracture is measured. The tensile elongation at break is calculated in the form of (spacing of the marks at fracture) / 50 mm (spacing of the marks before the test)×100 of the measurement result.

[0156] 4-15. Flexural Strength

[0157] The flexural strength of the polyurea foam can be set, for example, to 0.02 to 0.15 MPa, preferably 0.025 to 0.15 MPa. When the flexural strength is within this range, a polyurea foam having the effects of the present invention can be obtained. The flexural strength is measured by the method described in JIS K7221-2:2006 "Rigid Cellular Plastics - Flexural Test - Part 2: Method for Determining Flexural Properties".

[0158] 4-16. Charpy Impact Strength

[0159] The Charpy impact strength of the polyurea foam can be set, for example, to 1.0 to 3.0 kg·cm / cm 3 and preferably 1.2 to 3.0 kg·cm / cm 3 . When the Charpy impact strength is within this range, a polyurea foam having the effects of the present invention can be obtained. The Charpy impact strength is measured by the method described in JIS K7111-1:2012 "Plastics - Methods for Determining Charpy Impact Properties - Part 1: Non-Instrumented Impact Tests".

[0160] 4-17. Water Absorption

[0161] The water absorption of the polyurea foam can be set, for example, to 0.012 to 0.050%, preferably 0.015 to 0.045%. When the water absorption is within this range, a polyurea foam having the effects of the present invention can be obtained. The water absorption can be calculated by dividing the amount of water absorbed measured by Method B described in JIS A9511:2017 "Foamed Plastics Thermal Insulation Materials" by the initial weight of the polyurea foam.

[0162] 4-18. Punch Shear Strength

[0163] The punch shear strength of the polyurea foam can be set, for example, to 7 to 30 N / cm 2 and preferably 8 to 25 N / cm 2。When the punching shear strength is within this range, a polyurea foam having the effects of the present invention can be obtained. The punching shear strength is measured by the method described in JIS K7214:1985 "Test Method for Shearing of Plastics by Punching".

[0164] 4-19. Shore hardness (C hardness)

[0165] The Shore hardness (C hardness) of the polyurea foam can be set, for example, to 25 to 65, preferably 30 to 60. When the Shore hardness (C hardness) is within this range, a polyurea foam having the effects of the present invention can be obtained. The Shore hardness (C hardness) is measured by the method described in JIS K7215:1986 "Test Method for Shore Hardness of Plastics".

[0166] 4-20. Specific heat

[0167] The specific heat of the polyurea foam can be set, for example, to 0.15 to 0.35 kJ / (kg·°C), preferably 0.17 to 0.30 kJ / (kg·°C). When the specific heat is within this range, a polyurea foam having the effects of the present invention can be obtained. The specific heat is measured by the input compensation differential scanning calorimetry method described in JIS K7123:1987 "Method for Measuring Specific Heat Capacity of Plastics".

[0168] 4-21. Cone calorimeter measurement (total heat release)

[0169] The total heat release of the polyurea foam is measured using a cone calorimeter according to the test method of ISO-5660 under the condition of heating with a radiant heat intensity of 50 kW / m 2 And the total heat release after 10 minutes can be set to 15 MJ / m 2 Or less, preferably 10 MJ / m 2 Or less. Further, the total heat release after 20 minutes can be set to 15 MJ / m 2 Or less, preferably 10 MJ / m 2 Or less, more preferably 8 MJ / m 2 Or less. When the total heat release of the polyurea foam is within this range, a polyurea foam with particularly excellent flame retardancy is formed.

[0170] 5. Manufacturing method of polyurea foam

[0171] The urea resin composition of the present invention is prepared by premixing a polyisocyanate compound (A), a polyamine compound (B), a catalyst, a foaming agent, a foam stabilizer, red phosphorus, other flame retardants, and other additives. As the mixing method of the urea resin composition, a known method can be used. Specifically, in a container, the raw materials other than the polyisocyanate (A) are mixed using a mixer (for example, a mixer equipped with a propeller-type stirring blade) (for example, stirred at 2000 rpm for 5 minutes using the above-mentioned mixer) to prepare a composition for producing a polyurea foam. Next, the polyisocyanate (A) and the composition for producing a polyurea foam are each cooled to a specified temperature (for example, 10 ± 1 °C). Then, the polyisocyanate (A) and the composition for producing a polyurea foam are mixed (for example, stirred at 2000 rpm for 5 seconds using the above-mentioned mixer), and a urea resin composition can be obtained. Furthermore, by foaming and curing the urea resin composition, a polyurea foam can be obtained.

[0172] It should be noted that in the case of being used for a spraying process, a composition for producing a polyurea foam, which is prepared by premixing the raw materials other than the polyisocyanate, and the polyisocyanate compound (A) are respectively supplied to a spray gun (at this time, the nozzle of the spray gun is opened) using a pump or the like, and the composition for producing a polyurea foam and the polyisocyanate compound (A) are mixed in the chamber inside the spray gun, and then the body is sprayed to obtain a polyurea foam. The composition for producing a polyurea foam, which is prepared by premixing the raw materials other than the polyisocyanate compound (A), and the polyisocyanate compound (A) can be treated as a two-component system liquid. It should be noted that flame retardants, foam stabilizers, foaming agents, dispersants, and other additives that do not react with the polyisocyanate compound (A) can also be mixed with the polyisocyanate compound (A) and treated as a system liquid.

[0173] When the total amount of the urea resin composition is set to 100% by mass, the content of the polyamine compound (B) in the urea resin composition is 2.0% by mass or more, preferably 5.0% by mass or more, and more preferably 8.0% by mass or more. The upper limit of the content of the polyamine compound (B) can be set, for example, to 40.0% by mass or less, preferably 30.0% by mass or less, and more preferably 20.0% by mass or less. From other viewpoints, the content of the polyamine compound (B) in the urea resin composition can be adjusted such that the isocyanate index of the urea resin composition is 200 to 600, more preferably 200 to 500. Here, the isocyanate index is a value obtained by multiplying the ratio of the number of moles of isocyanate groups in the polyisocyanate compound (A) to the number of moles of all active hydrogens in the resin composition formulated as all raw materials by 100 (moles of NCO / moles of active hydrogen × 100). When the isocyanate index of the resin composition is within this range, a sufficient isocyanurate structure can be formed, and the isocyanuration rate can be made appropriate. Therefore, the flame retardancy of the polyurea foam can be made excellent.

[0174] It should be noted that when the polyurea foam production composition obtained by mixing raw materials other than the polyisocyanate compound (A) and the polyisocyanate compound (A) are treated as a two-component system liquid, when the sum of the polyurea foam production composition and the polyisocyanate compound (A) is set to 100% by mass, the content of the polyamine compound (B) in the polyurea foam production composition is 2.0% by mass or more, preferably 5.0% by mass or more, and more preferably 8.0% by mass or more. The upper limit of the content of the polyamine compound (B) can be set, for example, to 40.0% by mass or less, preferably 30.0% by mass or less, and more preferably 20.0% by mass or less. From other viewpoints, the content of the polyamine compound (B) in the polyurea foam production composition can be adjusted such that the isocyanate index when the polyurea foam production composition and the polyisocyanate compound (A) are mixed is 200 to 600, more preferably 200 to 500.

[0175] When the total content of the polyamine compound (B) in the urea resin composition is set to 100 parts by mass, the content of the polyisocyanate compound (A) in the urea resin composition can be set to 100 to 1000 parts by mass.

[0176] It should be noted that when the polyurea foam production composition and the polyisocyanate compound (A) are treated as a two-component system liquid, when the total content of the polyamine compound (B) in the polyurea foam production composition is set to 100 parts by mass, it can be set to 100 to 1000 parts by mass.

[0177] When the total content of the polyamine compound (B) in the urea resin composition or the composition for producing a polyurea foam is set to 100 parts by mass, the content of the foam stabilizer in the urea resin composition or the composition for producing a polyurea foam can be set to 0.1 to 20 parts by mass. Further, when the total mass of the polyurea foam is set to 100% by mass, the content of the foam stabilizer contained in the polyurea foam can be set to 0.1 to 20% by mass, preferably 0.5 to 15% by mass.

[0178] When the total content of the polyamine compound (B) in the urea resin composition or the composition for producing a polyurea foam is set to 100 parts by mass, the content of the flame retardant in the urea resin composition or the composition for producing a polyurea foam can be set to 10 to 200 parts by mass, preferably 30 to 150 parts by mass, more preferably 50 to 100 parts by mass. When the content of the flame retardant is within this range, a polyurea foam having excellent flame retardancy can be obtained. Further, when the total mass of the polyurea foam is set to 100% by mass, the content of the flame retardant contained in the polyurea foam can be set to 1 to 60% by mass, preferably 2 to 45% by mass.

[0179] When the total content of the polyamine compound (B) in the urea resin composition or the composition for producing a polyurea foam is set to 100 parts by mass, the content of red phosphorus in the urea resin composition or the composition for producing a polyurea foam can be set to 100 parts by mass or less, preferably 5 to 40 parts by mass, more preferably 25 to 40 parts by mass. Further, when the total mass of the polyurea foam is set to 100% by mass, the content of red phosphorus contained in the polyurea foam can be set to 0 to 30% by mass, preferably 1 to 30% by mass, more preferably 2 to 25% by mass. When the content of red phosphorus is within this range, a polyurea foam having more excellent flame retardancy can be obtained, and furthermore, the deterioration over time in a humid and hot environment can be suppressed. In particular, by increasing the ash content after thermal decomposition of the foam and forming a non-combustible carbonized layer at the initial stage of contact with a flame in the contact flame evaluation described below, the combustion can be prevented from proceeding to the deep part of the foam.

[0180] Further, when the total content of the polyamine compound (B) in the urea resin composition is 100 parts by mass, the total content of the flame retardants selected from phosphate esters, phosphate-containing flame retardants, bromine-containing flame retardants, boron-containing flame retardants, antimony-containing flame retardants, and metal hydroxides can be set to 10 to 200 parts by mass. Further, the ratio (Fp / Ft) of the content (Fp) of red phosphorus in the urea resin composition to the total content (Ft) of the flame retardants selected from phosphate esters, phosphate-containing flame retardants, bromine-containing flame retardants, boron-containing flame retardants, antimony-containing flame retardants, and metal hydroxides is not particularly limited, and can be set, for example, to 0.0 to 1.0, preferably 0.0 to 0.8, more preferably 0.09 to 0.73, and further preferably 0.45 to 0.73. When the blending of these flame retardants is within the above range, a polyurea foam having excellent flame retardancy and shape retention during combustion and capable of suppressing deterioration over time in a humid heat environment can be obtained.

[0181] When the total content of the polyamine compound (B) in the resin composition or the composition for producing a polyurea foam is 100 parts by mass, the content of the trimerization catalyst in the urea resin composition or the composition for producing a polyurea foam can be set to 0.1 to 30 parts by mass, preferably 1 to 20 parts by mass, more preferably 5 to 20 parts by mass, and further preferably 10 to 20 parts by mass. When the content of the trimerization catalyst is within this range, a polyurea foam with sufficient isocyanurate esterification, excellent flame retardancy and shape retention during combustion, and capable of suppressing deterioration over time in a humid heat environment can be obtained. Further, when the total mass of the polyurea foam is 100% by mass, the content of the trimerization catalyst contained in the polyurea foam can be set to 0.01 to 20% by mass, preferably 0.05 to 15% by mass.

[0182] When the total content of the polyamine compound (B) in the resin composition or the composition for producing a polyurea foam is 100 parts by mass, the content of the foaming agent in the urea resin composition or the composition for producing a polyurea foam can be set to 1 to 60 parts by mass, preferably 5 to 50 parts by mass. When the content of the foaming agent is within this range, a polyurea foam having excellent flame retardancy and shape retention during combustion and capable of suppressing deterioration over time in a humid heat environment can be obtained. Further, when the total mass of the polyurea foam is 100% by mass, the content of the foaming agent contained in the polyurea foam can be set to 1 to 40% by mass, preferably 3 to 30% by mass.

[0183] When using a catalyst other than the trimerization catalyst (such as a resinification catalyst, a foaming catalyst, etc.), when the total content of the polyamine compound (B) in the urea resin composition or the composition for producing a polyurea foam is set to 100 parts by mass, the content of the catalyst other than the trimerization catalyst can be set to 1 to 10 parts by mass. It should be noted that a compound having the functions of both a resinification catalyst and a foaming catalyst is defined as a substance incorporated as a resinification catalyst. In addition, when the total mass of the polyurea foam is set to 100% by mass, the content of the catalyst other than the trimerization catalyst contained in the polyurea foam can be set to 0 to 20% by mass, preferably 0.5 to 15% by mass.

[0184] 6. Uses of the polyurea foam

[0185] The polyurea foam of the present invention can be used for building applications (walls, ceilings, roofs, floors, etc.), building equipment (windows, sliding doors, doors, lattice doors, fences, etc.), ships for oil and gas transportation / storage tanks, vehicles (engines, batteries, ceilings, floors, door panels, etc.), airplanes, transport planes, cold insulation bags for transporting pharmaceuticals, refrigerators / freezers, factory facilities, and electrical products such as refrigerators, retaining walls, thermal insulation materials, heat materials, materials for alleviating thermal resistance, underground filling and reinforcement materials during anti-subsoil settlement works or road construction, injection repair materials for civil engineering applications such as tunnels, bridges, floating bridges, etc., filling materials for structural parts such as unwanted basements, energy absorption materials, waterproof materials, water stop materials, buoyancy materials, etc. In addition, in wooden or reinforced concrete buildings, etc., since thermal insulation construction is easy, it can be used as a polyurea foam for spray coating processes.

[0186] Examples

[0187] <<Production of the resin composition>>

[0188] <Raw materials>

[0189] (Polyamine compound (B))

[0190] ·ETHACURE 420 (manufactured by Albemarle Corporation, amine value: 562 mgKOH / g)

[0191] ·ELASMER 250P (manufactured by Kumiai Chemical Industry Co., Ltd., amine value: 254 mgKOH / g)

[0192] ·ANCAMINE2049 (manufactured by Evonik Industries AG, amine value: 484 mgKOH / g)

[0193] ·ELASMER 1000P (manufactured by Kumiai Chemical Industry Co., Ltd., amine value: 93 mgKOH / g)

[0194] (Polyol compound)

[0195] · MAXIMOL RLK-505 (manufactured by Kawasaki Kasei Chemicals Ltd., hydroxyl value: 250 mgKOH / g)

[0196] (Flame retardant)

[0197] · Tris(2-chloropropyl) phosphate (TMCPP, chlorine-containing phosphate ester)

[0198] · Resorcinol bis(diphenyl) phosphate (PFR, phosphate ester)

[0199] · Red phosphorus

[0200] · Ammonium polyphosphate (phosphate-containing flame retardant)

[0201] · Aluminum hypophosphite (hypophosphite-containing flame retardant)

[0202] · Sodium hypophosphite (hypophosphite-containing flame retardant)

[0203] · Decabromodiphenyl oxide (bromine-containing flame retardant)

[0204] · Zinc borate (boron-containing flame retardant)

[0205] · Antimony trioxide (antimony-containing flame retardant)

[0206] · Aluminum hydroxide (metal hydroxide flame retardant)

[0207] · Expanded graphite

[0208] · DOWSIL TM-4 7081 (manufactured by Dow Toray Co., Ltd., acrylic-modified silicone resin, silicone flame retardant)

[0209] (Foam stabilizer)

[0210] · SF2937F (silicone surfactant manufactured by Toray Dow Corning Co., Ltd.)

[0211] · DISPARLON SEI-1501 (manufactured by Kusumoto Chemicals, Ltd., acrylic polymer, organic surfactant)

[0212] (Catalyst)

[0213] · Bismuth 2-ethylhexanoate (bismuth-based catalyst)

[0214] · Dibutyltin dithiol (tin-based catalyst)

[0215] · N,N-Dimethylaminoethanol (foaming catalyst)

[0216] · Tetrakis(2-ethylhexyl glucoside) titanium (titanium-based catalyst)

[0217] ·TEDA (triethylenediamine, amine-based catalyst)

[0218] ·BDMAEE (bis(dimethylaminoethyl) ether)

[0219] ·1,2-dimethylimidazole

[0220] ·PMDETA (pentamethyldiethylenetriamine)

[0221] ·TOYOCAT-TRX (manufactured by Tosoh Corporation, trimerization catalyst)

[0222] ·U-CAT 18X (manufactured by San-Apro Limited, quaternary ammonium salt, trimerization catalyst) · diazabicycloundecene (trimerization catalyst)

[0223] ·1,3,5-tris(dimethylaminopropyl)hexahydro-s-triazine (trimerization catalyst)

[0224] · potassium octanoate (trimerization catalyst)

[0225] (foaming agent)

[0226] · Opteon1100 (manufactured by Mitsui Fluorochemicals Co., Ltd., HFO-1336mzZ, boiling point (b.p.) 33°C)

[0227] · Opteon1150 (manufactured by Mitsui Fluorochemicals Co., Ltd., boiling point 7°C)

[0228] · cyclopentane (boiling point 49°C)

[0229] · water (boiling point 100°C)

[0230] (polyisocyanate compound (A))

[0231] · MILLIONATE MR-200 (manufactured by Tosoh Corporation, NCO%: 30.9%, crude MDI)

[0232] · FOAMLITE MI (manufactured by BASF INOAC Polyurethane Co., Ltd., NCO%: 33.3%, monomer MDI)

[0233] · COSMONATE TM-50 (manufactured by Mitsui Chemicals SKC Polyurethane Co., Ltd., NCO%: 39.5%, TDI / MDI mixture)

[0234] · the urethane prepolymer manufactured by our company (NCO%: 27.0%, isocyanate group-terminated urethane prepolymer)

[0235] The urethane prepolymer manufactured by our company is prepared by the following method.

[0236] In a 5 L polyethylene container equipped with a mechanical stirrer, a fixed-type stirring blade, and a nitrogen inlet tube, a specified amount of crude MDI (manufactured by Tosoh Corporation, MILLIONATE MR-200) was added, and the liquid temperature of the isocyanate (crude MDI) was adjusted to 25°C. A specified amount of polypropylene glycol as a polyol (manufactured by Mitsui Chemicals SKC Polyurethane Co., Ltd., ACTCOL D2000, hydroxyl value: 55.1) was added thereto in stages in such a manner that the liquid temperature did not exceed 80°C. Starting from the moment when the addition of polypropylene glycol was completely finished, the mixture was stirred at a stirring speed of 60 rpm for 2 hours to cause the above-mentioned isocyanate and polyol to react, thereby obtaining an isocyanate-terminated prepolymer. The NCO group content of the obtained prepolymer was measured according to JIS K1603-1 (Method A), and it was confirmed that the specified NCO group content was achieved.

[0237] <Fabrication of Foam>

[0238] (Preparation of the mixture and foam used in evaluations other than the adhesiveness evaluation)

[0239] In a 500 mL disposable polypropylene cup, polyamine compounds, polyol compounds, trimerization catalysts, flame retardants, blowing agents, foam stabilizers, and other additives with the contents shown in Tables 1 to 7 for each of the examples and comparative examples were weighed to prepare the mixtures for each of the examples and comparative examples. Using a stirrer equipped with a propeller-type stirring blade, each mixture was stirred and mixed at 2000 rpm for 5 minutes to obtain the polyurea foam-producing compositions and polyol mixtures for each of the examples and comparative examples. They were placed in a cooling furnace at 10°C, and the obtained polyamine mixture and the polyisocyanate weighed with the contents recorded in Tables 1 to 7 were separately cooled to 10 ± 1°C. Using a stirrer equipped with a propeller-type stirring blade, the polyamine mixture and polyol mixture for each of the examples and comparative examples were stirred and mixed with the polyisocyanate at 2000 rpm for 5 seconds to cause foaming and curing, thereby obtaining the foams for each of the examples and comparative examples.

[0240] It should be noted that in the adhesiveness evaluation, for the substances obtained by separately cooling the polyamine mixture and polyol mixture for each of the examples and comparative examples and the polyisocyanate weighed with the contents recorded in Tables 1 to 7 to 10 ± 1°C, they were mixed using a manual sprayer for spraying rigid urethane foam described later and sprayed onto the object, thereby forming the foam for adhesiveness evaluation.

[0241] <<Evaluation>>

[0242] The foams of each example and comparative example were evaluated as follows. For each foam, the foam after foaming and standing for 24 hours for curing in an environment at a temperature of 23 ± 5°C and a relative humidity of 50 ± 20% was used. In addition, the evaluation described as "after hydrothermal treatment" means that the foams of each example and comparative example after curing were subjected to hydrothermal treatment in an environment at 80°C and RH85% for one month and used as the measurement specimens after hydrothermal treatment of each example and comparative example for measurement. The measurement method was the same as the measurement method when "hydrothermal treatment" was not performed.

[0243] <Determination of isocyanurate esterification rate>

[0244] Using a Fourier transform infrared spectrometer (FT-IR, model FT / IR-4200 manufactured by JASCO Corporation), the infrared absorption spectra of the foams of each example and comparative example were measured. The measurement was carried out by the ATR method using a diamond prism, and the number of accumulations was set to 50 times for measurement. The isocyanurate esterification rate in the foam was calculated from Equation 1. The measurement was performed at three points: the upper part, the central part, and the bottom part in the upward direction of foaming, and the average value was taken. The measurement results are shown in Tables 1 to 7.

[0245] (Observed peak)

[0246] P1: The peak area derived from the isocyanurate ester structure contained in the absorption spectrum of the foam obtained by infrared spectroscopic analysis (observation range: 1380 - 1430 cm -1 )

[0247] P2: The peak area of C=O derived from the urea structure contained in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis (observation range: 1550 - 1640 cm -1 )

[0248] P3: The peak area of C=O derived from the urethane structure and the isocyanurate ester structure contained in the absorption spectrum of the foam obtained by infrared spectroscopic analysis (observation range: 1680 - 1730 cm -1 )

[0249] P4: The peak area of N-H contained in the polyurea structure and the urea structure contained in the absorption spectrum of the foam obtained by infrared spectroscopic analysis (observation range: 1470 - 1550 cm -1 )

[0250] (Equation 1)

[0251] Isocyanurate esterification rate = P1 / (P1 + P2 + P3 + P4) × 100

[0252] <Density>

[0253] The apparent density of the foams of each example and comparative example was measured by the method described in JIS K7222:2005 "Plastic foams and rubbers - Determination of apparent density". The results are shown in Tables 8 to 14.

[0254] <Average cell (bubble) diameter and cell shape>

[0255] The polyurea foam - forming composition and polyol mixture of each example and comparative example were mixed with polyisocyanate by the above - mentioned method, foamed and cured in a mold to obtain the foams of each example and comparative example. Test pieces with a length of 50 mm × width of 50 mm × thickness of 20 mm were cut from the obtained foams, and a digital microscope (VHX - 800 manufactured by Keyence Corporation) was used to observe the bubbles in the CD plane and MD plane, and their shapes were confirmed. At this time, 10 bubbles in the CD plane were randomly selected, and the difference (DR = R1 - R2) between the longest diameter (designated as R1) in the CD plane of each bubble and the diameter in the direction orthogonal to the longest diameter (designated as R2) was calculated. When the average value of DR of all the selected bubbles exceeded 5 mm, it was judged as elliptical. In addition, when it was 0 mm or more and 5 mm or less, it was judged as circular.

[0256] In addition, 10 bubbles in the CD plane and 10 bubbles in the MD plane were randomly selected respectively, and the lengths of their major axes were measured. The values after averaging were used as the average cell diameter in the CD plane and the average cell diameter in the MD plane. In addition, the ratio of the average cell diameter in the MD plane to the average cell diameter in the CD plane (average cell diameter in the MD plane / average cell diameter in the CD plane) was calculated. The results are shown in Tables 8 to 14.

[0257] <Closed - cell ratio>

[0258] The closed - cell ratio of the foams of each example and comparative example was measured by the following method. The foams of each example and comparative example were processed into test pieces with a length of 30 mm × width of 30 mm × thickness of 20 mm. The lengths of each side were accurately measured, and the apparent volume (V) of the test piece was calculated. The mass (W) of the test piece was measured. A dry - type automatic density meter (Micromeritic AccuPyc II 1340 manufactured by Shimadzu Corporation) was used to measure the actual volume (V1) of the test piece. Using these values, the value calculated by the following formulas 2 to 4 was used as the closed - cell ratio. It should be noted that each measurement was carried out in an environment with a temperature of 23 ± 5°C and a relative humidity of 40 to 70%.

[0259] (Formula 2)

[0260] Open - cell ratio (%) : Oc=(V - V1) / V×100

[0261] (Formula 3)

[0262] Resin content of the polyurea foam: S = W / (V×D)×100

[0263] D is set as the density of the resin of the polyurea foam itself.

[0264] (Equation 4)

[0265] Closed cell ratio: Cc = 100 - Oc - S

[0266] The results are shown in Tables 8 - 14.

[0267] <Temperature at 5% weight loss>

[0268] Take about 10 mg of the foams of each example and comparative example respectively, and use a thermogravimetric analyzer (abbreviation: TGA) to measure the temperature at which the sample weight decreases by 5% by weight when heating from 25°C to 600°C. The measurement conditions are that the heating rate is set to 10°C / minute and carried out under an air flow of 200 ml / minute. The results are shown in Tables 8 - 14. In addition, the foams after hydrothermal treatment are also measured, and the results are shown in Tables 15 - 21.

[0269] <Measurement of ash content (600°C, 700°C)>

[0270] Collect 3 - 5 mg from the central part of the foams of each example and comparative example, fill the samples in an aluminum pan (for measurement at 600°C) or a platinum pan (for measurement at 700°C), use a TG / DTA analyzer (model TG / DTA7200 manufactured by SII Corporation), observe the weight loss behavior of the samples in the temperature range of 25 - 600°C or 25 - 700°C, and calculate the ash content (%) of each foam from the remaining weight of the sample at 600°C or 700°C. The measurement is carried out with a heating rate of 10°C / minute under a dry air flow (flow rate: 250 mm / minute). The results are shown in Tables 8 - 14. In addition, the foams after hydrothermal treatment are also measured, and the results are shown in Tables 15 - 21.

[0271] <Retention (300°C×30 minutes, 500°C×30 minutes)>

[0272] Use a differential thermal / thermogravimetric synchronous analyzer (TG / DTA) to measure the remaining weight of each foam after heating the foams of each example and comparative example to 300°C or 500°C and then holding for 30 minutes, and divide it by the weight of the initial polyurea foam to obtain the retention weight (weight %). The measurement is carried out with a heating rate of 10°C / minute, heating to the specified temperature and holding. In addition, the evaluation is carried out under a dry air flow (flow rate: 250 mm / minute). The results are shown in Tables 8 - 14. In addition, the foams after hydrothermal treatment are also measured, and the results are shown in Tables 15 - 21.

[0273] <Compressive strength>

[0274] The compressive strength of the foams of each example and comparative example was measured by the method described in JIS K7220:2006 "Rigid cellular plastics - Determination of compressive properties". The results are shown in Tables 8 to 14. In addition, the foams after hydrothermal treatment were also measured, and the results are shown in Tables 15 to 21.

[0275] <Adhesive strength>

[0276] The adhesive strength of the foams of each example and comparative example was measured by the method described in JIS A9526:2015 "Sprayed rigid urethane foam for building insulation". The results are shown in Tables 8 to 14. In addition, the foams after hydrothermal treatment were also measured, and the results are shown in Tables 15 to 21.

[0277] <Measurement of thermal conductivity>

[0278] The thermal conductivity of the foams of each example and comparative example was measured in accordance with JIS A1412-1:2016 "Methods for determination of thermal resistance and thermal conductivity of thermal insulating materials - Part 1: Guarded hot plate method (GHP method)". The results are shown in Tables 8 to 14. In addition, the foams after hydrothermal treatment were also measured, and the results are shown in Tables 15 to 21.

[0279] <Compressive elastic modulus>

[0280] The compressive elastic modulus of the foams of each example and comparative example was measured by the method described in JIS K7220:2006 "Rigid cellular plastics - Determination of compressive properties". The results are shown in Tables 8 to 14. In addition, the foams after hydrothermal treatment were also measured, and the results are shown in Tables 15 to 21.

[0281] <Water vapor transmission coefficient (water vapor permeability)>

[0282] The water vapor transmission coefficient of the foams of each example and comparative example was measured by the method described in JIS K7225:2018 "Rigid cellular plastics - Determination of water vapor transmission". The results are shown in Tables 8 to 14.

[0283] <Tensile strength>

[0284] The tensile strength of the foams of each example and comparative example was measured by the method described in JIS A9511:2017 "Foamed plastic thermal insulation materials". The results are shown in Tables 8 to 14.

[0285] <Tensile elongation>

[0286] The tensile elongation of the foams of each example and comparative example was measured by the following method. Test pieces were prepared according to the description in JIS A9511:2017 "Thermal insulation materials of foamed plastics". Two marking lines with a spacing of 50 mm in the tensile direction were drawn in parallel. Using a materials testing machine, the test pieces were tested at a tensile speed of 500 mm / min, and the spacing between the above-mentioned marking lines until fracture was measured. Regarding the tensile elongation, the results calculated in the form of (spacing of the marking lines at fracture) / 50 mm (spacing of the marking lines before the test)×100 are shown in Tables 8 to 14.

[0287] <Flexural strength>

[0288] The flexural strength of the foams of each example and comparative example was measured by the method described in JIS K7221-2:2006 "Rigid foamed plastics - Flexural test - Part 2: Method for determining flexural properties". The results are shown in Tables 8 to 14.

[0289] <Charpy impact strength>

[0290] The Charpy impact strength of the foams of each example and comparative example was measured by the method described in JIS K7111-1:2012 "Plastics - Methods for determining Charpy impact properties - Part 1: Non-instrumented impact test". The results are shown in Tables 8 to 14.

[0291] <Water absorption>

[0292] The water absorption of the foams of each example and comparative example was calculated by dividing the water absorption measured by Method B described in JIS A9511:2017 "Thermal insulation materials of foamed plastics" by the initial weight of each foam. The results are shown in Tables 8 to 14.

[0293] <Punch shear strength>

[0294] The punch shear strength of the foams of each example and comparative example was measured by the method described in JIS K7214:1985 "Test method for shearing plastics by punching". The results are shown in Tables 8 to 14.

[0295] <Shore hardness (C hardness)>

[0296] The Shore hardness (C hardness) of the foams of each example and comparative example was measured by the method described in JIS K7215:1986 "Test method for Shore hardness of plastics". The results are shown in Tables 8 to 14.

[0297] <Specific heat>

[0298] The specific heat of the foams of each example and comparative example was measured by the input compensation differential scanning calorimetry method described in JIS K7123:1987 "Method for Measuring the Specific Heat Capacity of Plastics". The results are shown in Tables 8 to 14.

[0299] <Dimensional change before and after damp heat treatment>

[0300] The foams of each example and comparative example were subjected to damp heat treatment for one month in an environment of 80 °C and RH85%, and the dimensional change rate before and after the damp heat treatment was measured. The measurement specimen of the foam was set to a length of 100 mm × width of 100 mm × thickness of 20 mm, and the dimensions of the measurement specimen were measured using a vernier caliper. The results are shown in Tables 15 to 21.

[0301] <Volume change rate (600 °C)>

[0302] Samples with a length of 5 cm × width of 5 cm × thickness of 5 cm were cut from the center of the foams of each example and comparative example, and left in an electric furnace heated to 600 °C for 5 minutes to measure the volume change rate. The volume before heating was set to 100%, the volume after heating was measured, and the value obtained by dividing the value obtained by subtracting the volume before heating from the volume after heating by the volume before heating and multiplying by 100 was used as the volume change rate. It is shown as a positive value in the case of expansion and a negative value in the case of contraction. The results are shown in Tables 15 to 21.

[0303] <Adhesiveness>

[0304] Using a manual sprayer for rigid urethane foam spraying (manufactured by ADY Co., Ltd.), the polyamine mixture and polyol mixture of each example and comparative example were mixed and sprayed separately with the polyisocyanate weighed at the contents described in Tables 1 to 7, which were independently cooled to 10 ± 1 °C, onto the surface of a wooden board with a surface temperature of 15 °C to cause foaming on the surface of the wooden board. Then, it was cured for 24 hours. A specimen without peeling or warping at the adhesive interface between the wooden board and the foam was evaluated as 1 point, and a specimen with peeling or warping was evaluated as 0 point. The results are shown in Tables 15 to 21.

[0305] <Flame contact test>

[0306] Samples in the form of rectangular parallelepipeds with a length of 10 cm, a width of 10 cm, and a thickness of 5 cm were cut from the foams of each of the examples and comparative examples 24 hours after foaming. The obtained samples were placed on a metal mesh with a length of 10 cm, a width of 10 cm, and a thickness of 1 mm, and the surface of the sample was brought into contact with a flame using a gas burner for 3 minutes. Methane gas with a purity of 99.5% or more was used as the combustion gas, and the combustion gas was supplied at 0.2 MPa to form a blue-white flame. This was carried out in such a way that the flame height was 5 cm and the distance between the flame and the sample surface was 1 cm. After contact with the flame, the sample was cut in half, and the cross-section was visually observed for cracks. In addition, the maximum distance of the portion carbonized to black in the cross-section (the length of the carbonized portion from the side surface of the cross-section) was measured as the depth of the carbonized layer. The results are shown in Tables 1 to 3. In addition, the evaluation was determined by the following evaluation criteria, and the results are shown in Tables 15 to 21. It should be noted that "not measurable" in the table means that it was impossible to measure because the flame passed through the sample during contact with the flame.

[0307] <Measurement of Total Heat Release (50 kW×10 min, 20 min)>

[0308] Samples with a length of 10 cm, a width of 10 cm, and a thickness of 5 cm were cut from the central part of the foams of each of the examples and comparative examples, and in accordance with the standard of ISO-5660 (No. 2 of the Japanese Building Standards Law), a cone calorimeter total heat release test of the foams was carried out to measure the total heat release and the maximum heat release rate of the samples. During the measurement, the radiant heat was set to 50 kW / m 2 and the measurement time was set to 10 minutes and 20 minutes. The results are shown in Tables 15 to 21. It should be noted that "not measurable" in the table means that during the test, the expanded sample did not come into contact with the tip of the spark plug of the cone calorimeter to generate a spark, making normal measurement impossible.

[0309] For the foams of each of the examples and comparative examples, a UL94 flammability test was carried out in accordance with Standard 5VA to measure the burning distance, burning time, presence or absence of dripping / cotton ignition, presence or absence of flame penetration, and the size of the penetration hole.

[0310] <Evaluation Using an Actual Machine (Spraying)>

[0311] In a barrel-shaped container, weigh the polyamine compound, flame retardant, catalyst, foam stabilizer, and foaming agent according to the formulations of Examples 1, 18, and 92 described in Tables 1, 2, and 7. Stir for 5 minutes at room temperature using a power mixer (manufactured by Ryobi, model PM-1511) to prepare an amine mixture (system liquid). Equip the device main body (manufactured by Graco, HR-V) with a spray gun (manufactured by Graco, Fusion Gun), and set the temperature control of the pump and hose to 40°C. Operate the pump and adjust the hydraulic pressure difference between the amine mixture (system liquid) and the polyisocyanate that has been sufficiently stirred separately to be within 2.0 MPa. Open the nozzle of the spray gun, mix the amine mixture (system liquid) and the isocyanate in the chamber of the spray gun, spray the body, prepare the foams of Examples 1, 18, and 92, and conduct the same evaluation as the method without using the above spraying. Foams with the same formulations as Examples 1, 18, and 92 respectively obtained the same results as the evaluation results of Examples 1, 18, and 92.

[0312]

[0313]

[0314]

[0315]

[0316]

[0317]

[0318]

[0319]

[0320]

[0321]

[0322]

[0323]

[0324]

[0325]

[0326]

[0327]

[0328]

[0329]

[0330]

[0331]

[0332]

Claims

1. A urea resin composition which is a urea resin composition containing a polyisocyanate compound (A), a polyamine compound (B), a trimerization catalyst, a foaming agent, and a foam stabilizer. Wherein, it does not contain a polyol compound, or the content of the polyol compound is 1 / 5 or less by mass ratio relative to the content of the polyamine compound (B).

2. A polyurea foam which is a polyurea foam formed by foaming and curing the urea resin composition according to Claim 1.

3. A composition for producing a polyurea foam which is a composition for producing a polyurea foam containing a polyamine compound (B), a trimerization catalyst, a foaming agent, and a foam stabilizer. Wherein, it does not contain a polyol compound, or the content of the polyol compound is 1 / 5 or less by mass ratio relative to the content of the polyamine compound (B).

4. A urea resin composition which contains a polyisocyanate compound (A), a polyamine compound (B), a trimerization catalyst, a foaming agent, a foam stabilizer, and a flame retardant. The polyamine compound (B) is selected from one or more of the group consisting of 4,4'-diamino-3,3'-dichlorodiphenylmethane, trimethylenebis(4-aminobenzoate), 4,4'-diamino-3,3'-diethyl-5,5'-dimethyl diphenylmethane, polytetrahydrofuran-bis(p-aminobenzoate), 2,2',6,6'-tetraethyl-4,4'-methylenedianiline, 4,4'-methylenebis(2-isopropyl-6-methylaniline), 4,4'-methylenebis(2,6-diisopropylaniline), 4,4'-methylenebis(3-chloro-2,6-diethylaniline), 3,5-diethyltoluene-2,4-diamine, and dimethylthiotoluenediamine.

5. A urea resin composition which is a urea resin composition containing a polyisocyanate compound (A), a polyamine compound (B), a trimerization catalyst, a foaming agent, a foam stabilizer, and a flame retardant. It is characterized in that, when the total amount of the urea resin composition is set to 100% by mass, the content of the polyamine compound (B) is 2.0% by mass or more. When the content of the polyamine compound (B) in the urea resin composition is set to 100 parts by mass, the content of the trimerization catalyst is 5 to 20 parts by mass.

6. A polyurea foam which is a polyurea foam produced using a urea resin composition, containing a flame retardant and having an isocyanurate structure. The urea resin composition is a urea resin composition containing a polyisocyanate compound (A), a polyamine compound (B), a trimerization catalyst, a foaming agent, and a foam stabilizer. Wherein, it does not contain a polyol compound, or the content of the polyol compound is 1 / 5 or less by mass ratio relative to the content of the polyamine compound (B). It is characterized in that, the isocyanuration rate of the polyurea foam is 25 to 50%, It should be noted that the isocyanuration rate is a value calculated by the following formula (1) based on the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis. (Formula 1) Isocyanuration rate (%) = P1 / (P1 + P2 + P3 + P4) × 100 P1: The peak area derived from the isocyanurate structure contained in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis, P2: The peak area of C=O derived from the urea structure contained in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis, P3: The peak area of C=O derived from the urethane structure and the isocyanurate structure contained in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis, P4: The peak area of N-H contained in the urethane structure and the urea structure in the absorption spectrum of the polyurea foam obtained by infrared spectroscopic analysis.

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