JP2000230028A - Rigid polyurethane foam original solution and rigid polyurethane foam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an original solution contg. an active hydrogen for rigid polyurethane foam capable of increasing the concn. of arom. rings in a foam without increasing the viscosity of the original solution, capable of manufacturing it using conventional production facilities, and capable of attaining flame resistance level required for architectural use, and having a small friability, and excellent in adhesion strength with a face material, and a rigid polyurethane foam therewith. SOLUTION: This is a rigid polyurethane foam original solution contg. a polyol component forming a rigid polyurethane foam by reacting with an isocyanate component, and a contains as polyol compds., an arom. multifunctional polyol compd. having a structure of condensate of an arom. polycarboxylic acid, a phenoxy alcohol compds., and a polyhydric alcohol and a polyether polyol having an average number of functional group of 2-8 and a hydroxyl group value of 200-500(mg KOH/g), and the content of the arom. multifunctional polyol compd. of 60-95 wt.% of the total polyol components.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stock solution of rigid polyurethane foam which forms a heat insulating material which is excellent in flame retardancy and heat resistance and has good adhesive strength to a face material, and a heat insulating material using the stock solution of polyurethane. Related to a rigid polyurethane foam.

[0002]

2. Description of the Related Art As is well known, a rigid polyurethane foam is prepared by mixing a polyisocyanate stock solution containing a polyisocyanate compound (P component), an active hydrogen group-containing compound generally called a polyol, and a stock solution containing a foaming agent (R component). It is formed by reacting, and is widely used as a heat insulating material and a structural material in building applications, home appliances such as refrigerators, automobiles, and the like. Such a rigid polyurethane foam is a method based on a so-called in-situ foaming method at a building site,
Also, it is manufactured by a method using a line foaming device or the like in a production factory. Rigid polyurethane foams are required to have the following characteristics based on the above-mentioned applications and production methods. (1) A rigid polyurethane foam as a product has flame retardancy and heat resistance. (2) The raw material of the rigid polyurethane foam must have characteristics such as liquid viscosity in accordance with the capacity of the facility for producing the rigid polyurethane foam. (3) Good adhesion to other base materials, especially a base material that covers at least a part of the rigid polyurethane foam molded product, which is called a face material. (4) The brittleness of the rigid polyurethane foam, that is, the so-called flyability is small.

As a method for imparting flame retardancy and heat resistance to a rigid polyurethane foam, the addition of a compound called a flame retardant such as an organic phosphate, a halogen compound or antimony oxide is well known. A method of adding a hydrate of an organometallic complex to an isocyanate compound has also been proposed (Japanese Patent Application Laid-Open No. 7-165871).

However, the amount of the flame retardant added is limited only by the addition of the flame retardant due to the effects on the foaming characteristics at the time of production, the characteristics of the obtained rigid foam, and the capacity of the production equipment. On the other hand, as a method for imparting heat resistance and flame retardancy to the polyurethane skeleton itself, a method of using an aromatic polyol and introducing an aromatic ring into the polyurethane resin is known, and the use of an aromatic ring in combination with a flame retardant has been studied. ing.

[0005]

However, conventional aromatic polyol compounds have a high level of aromatic ring in a rigid polyurethane foam produced by using the same, and have a flame retardancy level required for building materials. Can not be achieved. Further, when the aromatic ring concentration is further increased by using the conventional method for producing an aromatic polyol compound, the viscosity of the obtained polyol compound becomes too high, which is contrary to the above-mentioned required characteristic (2). Will not be able to produce foam.

An object of the present invention is to increase the concentration of aromatic rings in a polyol component, and thus in a rigid polyurethane foam, without increasing the liquid viscosity of a raw material polyol, as compared with the case where a conventional aromatic polyol compound is used. As a result, it can be manufactured using conventional production equipment, and has improved flame retardancy and heat resistance, and also achieves the level of flame retardancy required for building applications. It is to provide a rigid polyurethane foam which is possible.

[0007] Another object of the present invention is to provide an undiluted solution containing a polyol component as an R component for a rigid polyurethane foam having a low flyability and, as a result, excellent adhesion strength to a face material, and an undiluted solution as an R component as a polyisocyanate undiluted solution. It is to provide a rigid polyurethane foam obtained by reacting.

[0008]

SUMMARY OF THE INVENTION The present invention provides a rigid polyurethane foam stock solution (R component) containing a polyol component which reacts with an isocyanate component (P component) to form a rigid polyurethane foam. An aromatic polyfunctional polyol compound having a structure in which an acid, a phenoxy alcohol compound and a polyhydric alcohol compound are condensed, an average number of functional groups of 2 to 8, and a hydroxyl value of 200 to 5
A polyether polyol of 00 (mgKOH / g) is contained as the polyol component, and the aromatic polyfunctional polyol compound accounts for 60 to 95% by weight of the total polyol compound.

The most significant feature of the present invention is that an aromatic polycarboxylic acid, a phenoxy alcohol compound and a polyhydric alcohol compound are condensed as an aromatic component as a part of the polyol component constituting the active hydrogen group-containing component. This is because a polyfunctional polyol compound is used, and the aromatic polyfunctional polyol compound can increase the concentration of the aromatic ring while keeping the liquid viscosity low. As a result, it is possible to obtain a rigid polyurethane foam that satisfies the flame retardancy required in the construction field using conventional manufacturing equipment.

An aromatic polyfunctional polyol compound obtained by using a phenoxy alcohol has a high aromatic ring concentration, a rigid polyurethane foam having high flame retardancy is obtained, and the liquid viscosity is reduced by a conventional polyurethane production apparatus. Can be suppressed to a low viscosity that can be used because a part of the hydroxyl group is capped using a phenoxy alcohol compound that is a monoalcohol having an aromatic ring, and the aromatic ring concentration in the molecule is reduced. It is thought that the important factor is that it can be increased while reducing hydrogen bonds based on hydroxyl groups.

A structure in which an aromatic polycarboxylic acid, a phenoxy alcohol compound and a polyhydric alcohol compound are condensed means that a hydroxyl group of a phenoxy alcohol and a polyhydric alcohol is condensed with a carboxyl group and bonded by an ester bond, and the entire molecule is formed. Means a chemical structure having a hydroxyl group derived from the other hydroxyl group of the polyhydric alcohol.

The average number of functional groups is 2 to 8, and the hydroxyl value is 2
By using a polyether polyol of from 0.00 to 500 (mgKOH / g) as a polyol component, it is possible to greatly improve the flyability while maintaining the flame retardancy and heat resistance of a polyurethane foam obtained using this stock solution. As a result, it has become possible to greatly improve the adhesive strength between the foam and the face material in a molded article such as a board or panel of a rigid polyurethane foam manufactured using the face material.

If the average number of functional groups in the polyether polyol is less than 2, the physical properties of the foam will be reduced. If it exceeds 8, the viscosity of the polyol component will increase and the reactivity with the isocyanate component will decrease, resulting in a decrease in flyability. Invite. If the hydroxyl value is less than 200, the strength of the foam decreases, and if it exceeds 500, the flame retardancy and the adhesive strength to the face material decrease, which are both undesirable.

When the content of the aromatic polyfunctional polyol compound is less than 60% by weight of the total polyol compound, the flame retardancy is insufficient, and when it exceeds 95% by weight, the adhesive strength with the face material is insufficient. In consideration of a sufficient balance between the adhesive strength of the foam and the face material and the flame retardancy, it is more preferable that the aromatic polyfunctional polyol compound accounts for 60 to 85% by weight of all the polyol compounds.

In the polyurethane foam, in a narrow sense, polyurethane molecules are formed only by urethane bonds, but the polyurethane foam according to the present invention includes urea bonds, isocyanurate bonds, burette bonds and the like in addition to urethane bonds. In addition, it means a polyurethane foam in a broad sense in which a polymer skeleton is formed by two or more kinds of bonds.

In the stock solution of the rigid polyurethane foam of the present invention, it is preferable to use water as a foaming agent.

As the foaming agent used in the stock solution of the rigid polyurethane foam of the present invention, conventionally known freon-based foaming agents and halogenated hydrocarbon-based foaming agents can be used. Considering the influence, water foaming is most preferable, and the use of the aromatic polyfunctional polyol compound which is a feature of the present invention makes it possible to use a rigid polyurethane having excellent flame retardancy, heat resistance, and adhesive strength with a face material even in the case of water foaming. A form is obtained.

When water is used as the foaming agent, its addition amount is 2 to 10 parts by weight, preferably 3 to 8 parts by weight, when the total amount of the polyol compound is 100 parts by weight.

In particular, when a conventional aromatic polyol is used, the rigid polyurethane foam produced by foaming with water is not satisfactory in flame retardancy, but the foam obtained by using the stock solution of the present invention has poor flame retardancy or fly resistance. Physical properties such as abilities become excellent.

The use of the rigid polyurethane foam stock solution of the present invention makes it possible to produce a water-foamed rigid polyurethane foam using the conventional production equipment for rigid polyurethane foam using fluorocarbon.

The present invention relates to a rigid polyurethane foam formed by reacting an isocyanate component containing an isocyanate group-containing component with a stock solution of a rigid polyurethane foam containing an active hydrogen group-containing component. Aromatic polyfunctional polyol compound having a structure in which a polycarboxylic acid, a phenoxy alcohol compound and a polyhydric alcohol compound are condensed, an average number of functional groups of 2 to 8, and a hydroxyl value of 200 to 500 (mgKOH
/ G) as a polyol component, and the aromatic polyfunctional polyol compound is contained in an amount of 60 to 95% by weight of the total polyol compound.

In the above rigid polyurethane foam, it is preferable to use water as a foaming agent.

The rigid polyurethane foam of the present invention comprises
It is preferable that at least a part of the surface material is at least a part of paper, a resin film, an aluminum foil, and a steel plate.

Even when water is used as a foaming agent, it is possible to obtain a heat insulating material and a structural material which are excellent in flame retardancy and have good adhesive strength to these face materials.

[0025]

DETAILED DESCRIPTION OF THE INVENTION As described above, the aromatic polyfunctional polyol compound used in the rigid polyurethane foam stock solution of the present invention is a reaction for condensing an aromatic polycarboxylic acid, a phenoxy alcohol compound and a polyhydric alcohol compound.
Alternatively, it is synthesized by a transesterification reaction of an aromatic polycarboxylic acid ester with a phenoxy alcohol compound and a polyhydric alcohol compound.

Examples of the above aromatic polycarboxylic acids include phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, and naphthalene 1,4-dicarboxylic acid. These aromatic polycarboxylic acids may be used alone or in combination of two or more.

[0027] In addition to the above aromatic polycarboxylic acids, it is also possible to use some aliphatic polycarboxylic acids in combination.

The phenoxy alcohol compound is a general term for monoalcohols having a phenoxy group or a substituted phenoxy group. Monoalcohols having a phenoxy group include ethylene glycol monophenyl ether, propylene glycol monophenyl ether, and polyoxyethylene glycol monophenyl ether. , Polyoxypropylene glycol monophenyl ether, polyoxyethylene-propylene glycol monophenyl ether, and the like.

As the above-mentioned substituted phenoxy group, a phenoxy group having an alkyl substituent on an aromatic ring is preferable, and specific examples of such a substituent include a methyl group, an ethyl group and an n-type group.
Or i-propyl group, octyl group, nonyl group and the like.Examples of the monoalcohol having a substituted phenoxy group include ethylene glycol nonyl phenyl ether, propylene glycol nonyl phenyl ether, polyoxyethylene glycol nonyl phenyl ether, and polyoxypropylene glycol nonyl. Examples thereof include phenyl ether and polyoxyethylene-propylene glycol nonyl phenyl ether.

The above phenoxy alcohol compounds are used alone or in combination of two or more.

As the polyhydric alcohol compound to be reacted with the aromatic polycarboxylic acid together with the phenoxy alcohol compound, bifunctional or higher functional polyhydric alcohol compounds generally used in the synthesis of polyurethane can be used. Examples of compounds include ethylene glycol, propylene glycol, 1,4-butanediol,
1,3-butanediol, 1,6-hexanediol,
Neopentyl glycol, 1,8-octanediol,
Examples thereof include polyethylene glycols such as 1,10-decanediol, diethylene glycol, triethylene glycol and tetraethylene glycol having a molecular weight of up to about 1,000, polypropylene glycols such as dipropylene glycol and tripropylene glycol, trimethylolpropane, glycerin and the like. These may be used alone or in combination of two or more. The aromatic polyfunctional polyol compound of the present invention is produced by dehydrating and condensing these acids with a phenoxy alcohol compound and a polyhydric alcohol. It is also possible to carry out dealcoholation condensation using a lower alcohol ester of the above aromatic polycarboxylic acid such as ethanol, and to form an ester bond using the above-mentioned aromatic polycarboxylic acid anhydride as a raw material. The reaction to be formed can be used in combination. The aromatic polyfunctional polyol compound uses a polyester compound containing the above aromatic polycarboxylic acid as a raw material,
It is also possible to synthesize using a transesterification reaction. Specifically, a polyester fiber or film containing polyethylene terephthalate as a main component, a PET bottle, or the like is preferably ground, mixed with the above-mentioned phenoxy alcohol compound and polyhydric alcohol compound, and subjected to a transesterification reaction.

In producing the aromatic polyfunctional polyol compound of the present invention, a well-known esterification reaction accelerating catalyst, for example, a basic compound such as sodium alcoholate, a metal catalyst such as alkyl titanates or organotin compounds, p-
Protonic acid catalysts such as toluenesulfonic acid, sulfuric acid, and hydrochloric acid, Lewis acid catalysts such as aluminum chloride and boron trifluoride, activated clay, and acidic ion exchange resins can be used.

The hydroxyl value of the aromatic polyfunctional polyol compound of the present invention can be arbitrarily set by selecting the type of aromatic polycarboxylic acid to be used, the type of polyhydric alcohol, the equivalent ratio between carboxyl group and hydroxyl group, and the like. However, considering the characteristics of the rigid polyurethane foam, 50 to 50
It is preferably 0 (mgKOH / g). In addition, it is preferable that both the acid value and the moisture content are low, and the acid value is 4 (m
gKOH / g) or less, and the water content is preferably 0.1% by weight or less.

In the present invention, the average number of functional groups used in combination with the aromatic polyfunctional polyol compound as the polyester polyol is 2 to 8, and the hydroxyl value is 200 to 500.
(MgKOH / g) polyether polyols are used in addition to polyhydric alcohols used for the synthesis of aromatic polyfunctional polyol compounds, and sucrose, sorbitol, pentaerythritol, etc.
A phenol such as bisphenol-A, or a primary or secondary amine obtained by subjecting at least one of ethylene oxide and propylene oxide to ring-opening addition polymerization can be used. In particular, the use of an ethylene oxide adduct is preferred because of a high degree of freedom in the mixing ratio with the aromatic polyfunctional polyol.

It is particularly preferred that the average number of functional groups of the polyether polyol is from 3 to 5, since the resulting rigid polyurethane foam has good adhesive strength to the face material. The above-mentioned polyhydric alcohols may be used alone or in combination of two or more as long as the average number of functional groups is within a predetermined range. Further, the hydroxyl value of the polyether polyol used in the present invention is 200 to 350, even if the amount used is small, the effect of improving the adhesive strength with the face material is large,
More preferred.

In the stock rigid polyurethane foam solution of the present invention, other active hydrogen group-containing compounds may be used in addition to the above-mentioned polyols. Water used as a foaming agent reacts with isocyanate groups to generate carbon dioxide gas, while also acting as an active hydrogen group-containing compound. As other active hydrogen group-containing compounds, glycols and low molecular weight aromatic diamines exemplified as the polyhydric alcohol compound to be reacted with the aromatic polycarboxylic acid are exemplified.

In producing the rigid polyurethane foam of the present invention, a catalyst, a flame retardant, a foaming agent, a coloring agent, an antioxidant and the like well known to those skilled in the art can be used.

As a catalyst, triethylenediamine, N
-Methylmorpholine, N, N, N ', N'-hexamethylethylenediamine, tertiary amines such as DBU, and metal catalysts such as dibutyltin dilaurate, dibutyltin diacetate and tin octylate as urethanization reaction catalysts The combination of a tertiary amine catalyst and a tin-based catalyst is particularly preferable.

Particularly, as the catalyst for forming an isocyanurate bond which contributes to the improvement of the flame retardancy in the structure of the polyurethane molecule, potassium acetate and potassium octylate can be exemplified. Among the above tertiary amine catalysts, the isocyanurate ring-forming catalyst is also included. Some also promote reactions. A catalyst that promotes isocyanurate bond formation and a catalyst that promotes urethane bond formation may be used in combination.

In the present invention, it is also a preferred embodiment to further add a flame retardant.
Examples thereof include metal compounds such as organic metal complexes, halogen-containing compounds, organic phosphates, antimony trioxide, and aluminum hydroxide.

Examples of the organometallic complex include metallocenes such as ferrocene and nickelocene, metal acetylacetonates such as iron acetylacetonate, 8-oxyquinoline metal complexes such as bis (8-oxyquinoline) copper, and bis (dimethylglycol). Examples of suitable compounds include dimethylglyoxime metal complexes such as oximo) copper and the like.
More than one species can be used in combination.

However, in these flame retardants, for example, when an organic phosphoric acid ester is excessively added, the physical properties of the obtained rigid polyurethane foam may be deteriorated, and a metal compound powder such as antimony trioxide is excessively added. This may cause problems such as affecting the foaming behavior of the foam, and the amount of addition is limited to a range that does not cause such problems.

As the foaming agent for the rigid polyurethane foam of the present invention, any foaming agent known as a foaming agent for polyurethane can be used, and a freon-based foaming agent such as CFC-141b and a halogenated hydrocarbon such as methylene chloride can be used. , Water, etc., and any of them can be used alone. As described above, water is the most preferable blowing agent, but other blowing agents can be used in combination.

The rigid polyurethane foam of the present invention includes:
It is preferable to use a plasticizer as needed. Such plasticizers also preferably contribute to flame retardancy, and halogenated alkyl esters of phosphoric acid, alkyl phosphates, aryl phosphates, phosphonates, and the like can be used. Specifically, tris ( Chloroethyl) phosphate, tris (β-chloropropyl)
Phosphate, tributyl phosphate, triethyl phosphate, cresyl phenyl phosphate, dimethyl methyl phosphonate and the like can be exemplified, and one or more of these can be used. The amount of the plasticizer added is the polyol component 10
The amount is preferably 5 to 30 parts by weight with respect to 0 parts by weight. If the ratio exceeds this range, problems may occur such that a sufficient plasticizing effect cannot be obtained or physical properties of the foam deteriorate.

The rigid polyurethane foam of the present invention is molded into a shape according to the application by a generally known polyurethane foam molding apparatus. For example, in a manufacturing factory, it is manufactured by a slab foam manufacturing apparatus using a mixed foaming apparatus or a laminate board manufacturing apparatus that foams while supplying various face materials, and is manufactured by a spray foaming apparatus in a building site or the like, and is used for an electric refrigerator. Rigid polyurethane foam as a heat insulating material is manufactured by an injection molding machine or the like.

As the face material of the rigid polyurethane foam of the present invention, known face materials can be used without particular limitation.
Specifically, paper, aluminum foil, steel plate and the like are exemplified. In particular, since the paper surface material is soft, the adhesive strength is reduced if the foam flyability is high. Therefore, the use of the rigid polyurethane foam stock solution of the present invention is preferred.

As the rigid polyurethane foam using the face material, a plate-like body such as a board or a panel used as a heat insulating material or a structuring agent is particularly preferable.

[0048]

(Synthesis example of polyol compound)

(Synthesis Example 1) A 1-liter four-necked flask equipped with a Dimroth condenser was charged with 212 g of diethylene glycol monophenyl ether, 344 g of diethylene glycol, 360 g of isophthalic acid and 1.1 g of a catalyst, and the mixture was stirred under a nitrogen stream. At 220-230 ° C
A heat dehydration condensation reaction was performed for 4 hours to obtain an aromatic polyfunctional polyol compound.

This polyol compound has a hydroxyl value of 245.
(MgKOH / g) and a viscosity of 2900 cps (25 ° C.). The aromatic polyester polyol compound which is the aromatic polyfunctional polyol compound is referred to as polyol A.

(Synthesis Example 2) 60.7 g of sorbitol and 61.3 g of glycerin were placed in a 1-liter autoclave.
g, and 2 g of the catalyst, and 926.6 g of ethylene oxide (EO) in a nitrogen stream while stirring the mixture.
Was added and heated to 120 ° C. to perform ring-opening polymerization to obtain a polyether polyol compound.

This polyol compound has a hydroxyl value of 214
(Mg KOH / g) and viscosity 770 cps (25 ° C.). This polyether polyol compound is referred to as polyol B.

(Synthesis Examples 3 to 6) Polyol C, which is the following polyether polyol, was prepared by a method similar to Synthesis Example 2.
~ F was obtained.

Polyol C: shoe cloth EO-added polyol. Hydroxyl value 252 (mgKOH / g), viscosity 6
50 (cps) Polyol D: sorbitol-based PO (propylene oxide) -added polyol. Hydroxyl value 216, viscosity 1200 Polyol E: polyethylene glycol. Hydroxyl value 28
1. Viscosity 70 Polyol F: shoe cloth PO-added polyol. Hydroxyl value 553, viscosity 18000 Isocyanate component (P component): Crude MDI (c-
MDI) and a compound having an isocyanate group concentration of 31.3 wt% or more were used, and a rigid polyurethane foam was prepared by the following method according to the composition shown in the upper part of Table 1. Other materials used in Table 1 were tris (β-chloropropyl) phosphate as a flame retardant and L as a foam stabilizer.
-5340 (silicon-based foam stabilizer, manufactured by Union Carbide Co.), and the catalyst is potassium octylate.

[Example of preparation of rigid polyurethane foam]
The components described as the components were weighed and rapidly mixed, and the c-MDI described as the P component was further added to this mixture, followed by rapid mixing. Immediately 200 mm long, 200 mm wide and 15 mm deep
A rigid polyurethane foam sample was prepared by injecting into a 0 mm mold and free-foaming.

[Evaluation] (Density) A 10 cm × 10 cm × 10 cm cubic cut sample was cut out from the hard polyurethane foam sample obtained in the above “Production Example of Hard Polyurethane Foam” except for the skin portion, and the weight was measured. The dimensions of the cut sample were accurately measured with calipers to determine the volume, and the density was calculated from the weight and volume.

(Smoke emission amount (NBS)) The measurement of the smoke emission amount, which is a criterion for the evaluation of flame retardancy, was carried out in accordance with ASTM-E662.

(Loss on Heating) The weight loss on heating (wt%) of the sample for measuring the amount of smoke generated was determined by the following equation. Heating raw material = [(W ₀ −W) / W ₀ ] × 100 where W ₀ is the sample weight before the test, and W is the sample weight after the test.

(Adhesive Strength) A mixture of the liquid P and the liquid R in the above-mentioned rigid polyurethane foam production example was cast on water-resistant kraft paper, which is a paper surface material generally used when producing a rigid polyurethane foam board. After that, another sheet of the same water-resistant kraft paper is quickly overlaid to form a sandwich, and the foam-forming mixture is adjusted to a thickness of 1 mm using a roller from above.

Next, the above-mentioned sandwich sheet was
Curing is performed in an oven at 0 ° C. to prepare a sample panel.

The upper and lower surfaces of the sample panel (on the side of the water-resistant kraft paper laminated after the above) and the lower surface are each 5 cm × 15 cm.
Then, as shown in FIG. 1, one end of the water-resistant kraft paper 3 was pulled and peeled in a direction of 45 degrees using a spring, and the adhesive strength F was measured. In FIG. 1, 1 is a rigid polyurethane foam, and 5 is a cut. The measurement results of the adhesive strength were obtained by measuring the adhesive strength at two points on the upper and lower surfaces of each sample panel for three sample panels, averaging the six measured values on the upper and lower surfaces, and displaying the averaged adhesive strength.

(Evaluation Results) The lower row of Table 1 shows the measurement results of the density, the amount of smoke generated, the weight loss on heating, and the adhesive strength with the face material of the rigid polyurethane foam.

[0062]

[Table 1] According to the results in this table, all of the rigid polyurethane foams of the present invention have good flame retardancy and good adhesion strength to the face material, but the foams using only the aromatic polyester polyol as the polyol component have a low flame retardancy. Although the amount of smoke, which is an evaluation item of the property, is 15 or less and the weight loss on heating is excellent at 50 or less, the adhesive strength with the surface material is low, and the performance as a sandwich panel is not sufficient (Comparative Example 1). When the proportion of the aromatic polyester polyol in the polyol compound is less than 60%, the flame retardancy is reduced (Comparative Examples 2, 3).
When a polyether polyol having a hydroxyl value of more than 500 is used, the flame retardancy and the adhesive strength with the face material are not sufficient.

[Brief description of the drawings]

FIG. 1 is a diagram showing a method for measuring the adhesive strength between a face material of a rigid polyurethane foam formed in a sandwich shape with the face material and the foam.

[Explanation of symbols]

 1 rigid polyurethane foam 3 face material 5 cut

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme court ゛ (Reference) C08J 9/02 CFF C08J 9/02 CFF (72) Inventor Futao Watanabe 1-17 Edobori, Nishi-ku, Osaka-shi, Osaka No. 18 Toyo Tire & Rubber Co., Ltd. (72) Inventor Riichiro Ohara 1-17-18 Edobori, Nishi-ku, Osaka-shi, Osaka AA01A AB03B AB10B AB33B AK01B AK51A BA02 CA01A DG10B DJ01A JJ07 JK06 JK12A 4J034 BA07 DA01 DB04 DB05 DB07 DC02 DC43 DF01 DF16 DF17 DF21 DF22 DG03 DG04 DG08 DG10 KA11 HC12 HA11 HC12 HA12 HA12

Claims (5)

[Claims] 1. A rigid polyurethane foam stock solution containing a polyol component that reacts with an isocyanate component to form a rigid polyurethane foam, having a structure in which an aromatic polycarboxylic acid, a phenoxy alcohol compound and a polyhydric alcohol compound are condensed. An aromatic polyfunctional polyol compound and a polyether polyol having an average number of functional groups of 2 to 8 and a hydroxyl value of 200 to 500 (mgKOH / g) are contained as the polyol component, and the aromatic polyfunctional polyol compound is contained in 6 of all polyol components.
A rigid polyurethane foam stock solution of 0 to 95% by weight. 2. The rigid polyurethane foam stock solution according to claim 1, which comprises water as a foaming agent. 3. A rigid polyurethane foam formed by reacting an undiluted rigid polyurethane foam solution containing an isocyanate component and a polyol component, wherein the undiluted rigid polyurethane foam solution comprises an aromatic polycarboxylic acid, a phenoxy alcohol compound, and a polyvalent alcohol. An aromatic polyfunctional polyol compound having a structure in which an alcohol compound is condensed, having an average number of functional groups of 2 to 8 and a hydroxyl value of 200
-500 (mgKOH / g) of the polyether polyol as the polyol component, wherein the aromatic polyfunctional polyol compound is 60-95% by weight of the total polyol component
Rigid polyurethane foam. 4. The rigid polyurethane foam according to claim 3, wherein water is used as a foaming agent. 5. The rigid polyurethane foam according to claim 3, wherein at least a part thereof is covered with at least one kind of face material of paper, resin film, aluminum foil, and steel sheet.