JPH1135727A - Thermally insulating panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermally insulating panel excellent in flame retardance and thermal insulation. SOLUTION: This thermally insulating panel is constituted by cast molding an isocyanurate-modified hard polyurethane foam raw material into the cavity of a panel body (1), the raw material being constituted by mixing-foaming a polyisocyanate component with a polyol component, a foaming agent, a catalyst, a foam regulating agent and other auxiliaries. The polyol component comprises a polyester-polyol compound with an acid value of >=5.0 mg-KOH/g in an amount of >=50 wt.% which is obtained by esterification of a hydroxy compound, and one or more polybasic acid components selected from the group of o-, m-, p-phthalic acids and their derivatives.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat insulating panel which is useful as a panel material or a board material for a building such as a refrigerated or frozen warehouse, a clean room, a detached house, etc., and more particularly to a heat insulating panel excellent in heat insulation and flame retardancy. .

[0002]

2. Description of the Related Art In recent years, there has been an increasing demand for heat insulation and airtightness from the viewpoint of energy saving for building panel materials and board materials for refrigerated or frozen warehouses, clean rooms, detached houses and the like.

Conventionally, as a main heat insulating material used for these applications, there are a cotton-like material such as glass wool and rock wool, and a plate-like material such as polystyrene foam, polyethylene foam and rigid polyurethane foam.

For example, as a panel material used for heat insulation and partitioning in refrigerated / frozen warehouses and clean rooms, there is a sandwich panel in which a rigid polyurethane foam is sandwiched between metal surface materials. Demand for large warehouses and clean rooms is increasing due to capital investment. In addition, the market for such sandwich panels is expected to grow in the future due to the high heat insulation performance of rigid polyurethane foam.

On the other hand, insulation materials for detached houses conventionally include:
Glass wool, rock wool, etc. have been used.However, these cotton-like materials tend to shift after construction, and the heat insulation performance of that part can not be maintained, or the heat insulation performance decreases due to moisture absorption or internal condensation, etc. There was a problem with stability.

In order to solve such a problem of the cotton-like material, a heat insulating panel has been developed in which a structural plywood is used as a face material and a hard polyurethane foam having high heat insulating performance is sandwiched. Such a heat-insulating panel can solve the problems of the cotton-like material, exhibit high heat-insulating properties and air-tightness, and can save labor and shorten the construction period by paneling.

[0007] The above-mentioned heat insulating panel using a rigid polyurethane foam as a heat insulating material is generally prepared by mixing a polyisocyanate component with a mixture of a polyol component, a foaming agent, a catalyst, a foam stabilizer and other auxiliaries. The isocyanurate-modified rigid polyurethane foam raw material obtained by mixing and foaming is injected into a hollow portion of a hollow panel body having a hollow portion composed of a surface material and a side frame material, and is manufactured by an injection molding method. Have been. Injection molding is widely used as a typical method for manufacturing heat-insulating panels using rigid polyurethane foam because the product dimensions can be arbitrarily designed, and since it can be molded integrally with the surface material and has high productivity. Have been.

[0008]

A rigid polyurethane foam used as a heat insulating material for a heat insulating panel used in a house or other applications is required to be able to maintain stable heat insulating properties and airtightness for a long period of time and to have a flame retardant property. It is required to be highly resistant and not easily spread in the event of a fire.

That is, even if a plywood is used as a surface material, even if a metal surface material is used, sufficient fire resistance cannot be obtained depending on the material and thickness of the surface material, the panel structure, and the like. In the event of a fire, the internal rigid polyurethane foam may ignite in a short time. Therefore, the flame retardancy of the rigid polyurethane foam is extremely important for use as a heat insulating panel.

In the case of a heat-insulated panel formed by injection molding, the filling and shrinkage of the raw material of the rigid polyurethane foam are also important. That is, if the filling property of the raw material of the rigid polyurethane foam is poor, an unfilled portion of the rigid polyurethane foam is generated in the panel, and heat insulation cannot be obtained in this portion. If the rigid polyurethane foam has a large shrinkage, voids are formed in the panel by shrinkage after injection molding, and heat insulation cannot be obtained in the voids.

The present invention has been made in view of the above circumstances, and is an insulating panel obtained by injection molding of a rigid polyurethane foam, which has excellent flame retardancy,
It is another object of the present invention to provide a heat insulating panel having no internal voids and excellent heat insulating properties.

[0012]

The heat insulation panel of the present invention comprises:
A liquid mixture in which a polyisocyanate component, a polyol component, a foaming agent, a catalyst, a foam stabilizer, and other auxiliaries are mixed in the hollow portion of a hollow panel body having a hollow portion composed of a surface material and a side frame material. And a foamed isocyanurate-modified rigid polyurethane foam obtained by injection molding, wherein the polyol component comprises a hydroxy compound, o-phthalic acid, m-phthalic acid, p-
1 selected from the group consisting of phthalic acid and derivatives thereof
A polyester polyol compound having an acid value of 5.0 mg-KOH / g or more (hereinafter referred to as a “specific acid value phthalic acid-based polyester polyol”) obtained by subjecting one or more kinds of polybasic acid components to an esterification reaction. ) Of at least 50% by weight.

[0013] The above-mentioned specific acid number phthalic acid-based polyester polyol has good flame retardancy and filling properties, and provides a heat insulating panel excellent in flame retardancy and heat insulating properties due to a rigid polyurethane foam having low shrinkage. You.

In the present invention, in particular, a reactive amine catalyst comprising an amine compound having one or more hydroxyl groups in one molecule is used as a catalyst in an amount of 10% by weight based on the polyol component.
It is preferable to use the following. In this case, remarkably good flame retardancy can be obtained by using the above-mentioned specific acid value phthalic acid-based polyester polyol in combination with the above-mentioned reactive amine catalyst.

Further, as the polyisocyanate component,
It is a polyisocyanate compound represented by the following general formula (I), in which the proportion of polymeric isocyanate of n ≧ 3 is less than 30% by weight (hereinafter, this proportion is referred to as “pentanuclear in polyisocyanate”). Of dinuclear diisocyanates having n = 0 and 4,4′-methylene diisocyanate represented by the following structural formula (II) (hereinafter referred to as “4,4 ′
-MDI ". ) (Hereinafter referred to as “MD”).
4,4'-isomer content in I ". ) Is 85% by weight or more (hereinafter, such a polyisocyanate is referred to as a “nucleus-controlled polyisocyanate”), and together with the specific acid value phthalic acid-based polyester polyol,
Alternatively, by using such a polyisocyanate component together with the specific acid value phthalic acid-based polyester polyol and the reactive amine catalyst, remarkably good flame retardancy can be obtained.

[0016]

Embedded image

Further, it is preferable to use a blowing agent which is a gas at normal temperature and normal pressure (hereinafter referred to as "low boiling point blowing agent") as a blowing agent in an amount of 10% by weight or less based on the total of the polyol component and the polyisocyanate component. By using such a low boiling point foaming agent, the shrinkage ratio can be suppressed to a small value, and the formation of voids in the panel can be prevented.

[0018]

Embodiments of the present invention will be described below in detail.

First, a raw material of isocyanurate-modified rigid polyurethane foam as a heat insulating material of the heat insulating panel of the present invention will be described.

The polyol component used for the isocyanurate-modified rigid polyurethane foam raw material is a hydroxy compound and one or more kinds selected from the group consisting of o-phthalic acid, m-phthalic acid, p-phthalic acid and derivatives thereof. A phthalic acid-based polyester polyol obtained by subjecting a polybasic acid component to an esterification reaction, and having an acid value of 5.
It contains 50% by weight or more of a phthalic acid-based polyester polyol having a specific acid value of 0 mg-KOH / g or more.

In the present invention, the acid value is 5.0 mg-KOH /
g or more of the polyester polyol,
In the injection molding of the raw material of isocyanurate-modified rigid polyurethane foam, good filling properties can be obtained. The acid value of the polyester polyol is 5.0 mg-KOH / g
If it is less than 10, the reaction will be too fast, and when pouring into a large panel or thick panel, the gelation will progress during the filling process and the viscosity will increase, and the voids and unfilled parts inside will become remarkable and a good heat insulating panel Can not be obtained. If the acid value of the polyester polyol is too high, the reaction does not proceed even if a catalyst is added, and the filling property is rather reduced. The preferred acid value of the polyester polyol is 6 to 12 mg-KOH / g, more preferably 8 to 10 mg-KOH / g. In addition, the adjustment of the acid value is usually performed by stopping the reaction during the ester synthesis to control the amount of the unreacted polybasic acid component, or by adding the acid component after the completion of the synthesis. it can.

In the present invention, stable flammability is obtained by using a large amount of phthalic polyester polyol containing an aromatic ring as the polyol component.

If the content of the phthalic acid-based polyester polyol in the polyol component is less than 50% by weight, sufficient flame retardancy and filling properties cannot be obtained. The specific phthalic acid-based polyester polyol content in the polyol component is preferably 60% by weight or more, more preferably 70% by weight or more.
% By weight, and in particular, by using 70% by weight or more of the specific acid value phthalic acid-based polyester polyol, a stable and reliable flame-retardant effect can be obtained, and good filling properties can be ensured. .

Examples of the hydroxy compound forming the phthalic acid-based polyester polyol include ethylene glycol, diethylene glycol, phenol, and compounds obtained by ring-opening addition polymerization of phenol with ethylene oxide, propylene oxide and the like. Include diethyl phthalate, dimethyl phthalate and the like. In addition, polyester polyols recycled and manufactured from residues such as PET (polyethylene terephthalate) are also included. The preferred hydroxyl value of the phthalic acid-based polyester polyol is from 150 to 450. As the phthalic acid-based polyester polyol, those having a high ratio of m-phthalic acid and / or p-phthalic acid in the polybasic acid are particularly preferable from the viewpoint of flame retardancy.

The content of the specific acid value phthalic acid-based polyester polyol according to the present invention is a ratio as a pure specific acid value phthalic acid-based polyester polyol,
It does not include hydroxy compounds, polybasic acid components, other additives, etc., which are not reacted in the product of the ester synthesis reaction.

In the present invention, as the polyol component, in addition to the specific acid value phthalic acid-based polyester polyol,
A polyol compound such as Mannich-modified polyol, ethylenediamine, tolylenediamine, sucrose, aminoalcohol, diethylene glycol and the like may be used in combination within the range of 30% by weight or less in the polyol component within a range not to impair the object of the present invention.

On the other hand, as the polyisocyanate component,
The polyisocyanate compound represented by the general formula (I), wherein the ratio of the polymer isocyanate with n ≧ 3 (the content of pentanuclear or more in the polyisocyanate) is less than 30% by weight in the polyisocyanate compound. And the proportion of 4,4′-MDI (content of 4,4′-MDI in MDI) represented by the following structural formula (II) in the binuclear diisocyanate of n = 0 is 85% by weight or more. A nucleus controlling polyisocyanate is used.

When the content of the nucleus controlling polyisocyanate is not less than 30% by weight in the polyisocyanate, or the content of the 4,4′-isomer in the MDI is 85%.
If it is less than 10% by weight, good flame retardancy cannot be achieved.

The nucleus controlling polyisocyanate of the present invention preferably has a pentanuclear or higher content of 5 to 25% by weight in the polyisocyanate. If the content is less than 5% by weight, the synthesis process is complicated, and at present, industrial Difficult to produce. The content of the 4,4′-form in MDI is preferably at least 90% by weight, more preferably at least 95% by weight.

The isocyanate index of the nucleus controlling polyisocyanate is preferably from 130 to 350, and is preferably from 150 to 250 in consideration of the overall performance balance such as improvement of flame retardancy and suppression of shrinkage. More preferred.

In the present invention, as the polyisocyanate component, a polyisocyanate compound other than the above-mentioned nucleus controlling polyisocyanate, for example, an alicyclic isocyanate such as isophorone diisocyanate, an aliphatic isocyanate such as hexamethylene diisocyanate and the like are used. It may be used, but in this case, it is necessary that the content of the pentanuclear compound or more and the content of the 4,4′-isomer in the entire polyisocyanate component are within the range of the present invention.

The reactive amine catalyst used in the present invention is an amine compound having one or more hydroxyl groups in one molecule.
Specific examples include dimethylaminohexanol, dimethylaminoethoxyethanol, trimethylaminoethylethanolamine, and other quaternary ammonium salts.

That is, amine catalysts conventionally used as catalysts for rigid polyurethane foams are compounds such as triethylenediamine, tetramethylhexamethylenediamine, pentamethyldiethylenetriamine, etc. It is presumed that this was the core of combustion because it remained in the free state. Therefore, in the present invention, flame retardancy is enhanced by using a reactive amine catalyst in place of such a conventional amine catalyst.

Incidentally, dibutyltin dilaurate, lead octylate, stannas octoate, potassium octylate (2
Organometallic catalysts such as potassium ethylhexylate) and potassium acetate are indispensable components for urethane bond and promotion of isocyanurate modification, and they do not impair the flame retardancy by use. .

In the present invention, the amount of the reactive amine catalyst used depends mainly on the casting conditions, but is not more than 10% by weight, preferably 5% by weight, based on the polyol component.
Hereinafter, the content is more preferably 0.1 to 5% by weight. If the amount of the reactive amine catalyst exceeds 10% by weight with respect to the polyol component, the flame retardant performance is rather lowered, and the filling property may be impaired.

The amount of the organometallic catalyst used (in the case of using a reactive amine catalyst, the total amount with the reactive amine catalyst) is preferably 1 to 10% by weight based on the polyol component.

As the blowing agent, dichloromonofluoroethane, pentafluoropropane, water and the like, preferably dichloromonofluoroethane, are used.

In the present invention, a blowing agent which is a gas at normal temperature and pressure, such as tetrafluoroethane (R134)
It is preferable to use a) or dichloromonochloromethanes (R22) of hydrochlorofluorocarbons, carbon dioxide, or the like. By using such a low boiling point blowing agent, a phthalic acid-based polyester polyol having a low functional group number is used. In this case, a decrease in strength due to the above-described process can be suppressed, and the shrinkage ratio can be reduced by increasing the internal pressure of the bubble, thereby improving dimensional stability.

In this case, the amount of the low boiling point blowing agent is preferably 10% by weight or less, particularly preferably 1 to 8% by weight, based on the total of the polyol component and the polyisocyanate component. If the amount of the low boiling point foaming agent exceeds 10% by weight based on the total of the polyol component and the polyisocyanate component, the vaporization power becomes too high, the foaming becomes unstable, and the foam is coarse and good foam is obtained. Can not be.

When this low boiling point foaming agent is used, the low boiling point foaming agent may be mixed with the polyol component in advance, or may be directly mixed with the polyol component and the polyisocyanate component alone as the third component at the time of foaming.

The total amount of the foaming agent used is arbitrarily determined according to the density of the target rigid polyurethane foam, but is usually 3 to 25% by weight based on the total of the polyol component and the polyisocyanate component. %, Preferably 5 to 15% by weight.

As foam stabilizers, all those effective for producing rigid polyurethane foams can be used. For example, a silicone-based material such as polyoxyalkylene alkyl ether can be used in a usual amount. Further, in the present invention, optional components other than those described above, for example, a flame retardant, a filler and the like can be used as long as the object of the present invention is not hindered.

The isocyanurate-modified rigid polyurethane foam raw material according to the present invention essentially requires the use of the above-mentioned phthalic acid-based polyester polyol.
Even better properties can be obtained by using a reactive amine catalyst and / or a nucleus controlling polyisocyanate in combination, and further by using a low boiling point blowing agent in combination.

The heat insulating panel of the present invention comprises a blending component obtained by mixing a foaming agent, a catalyst, a foam stabilizer and other auxiliaries with a polyol component, a polyisocyanate component, and a low-boiling foaming agent when a low-boiling foaming agent is used. The isocyanurate-modified rigid polyurethane foam raw material obtained by mixing and foaming the third component of the foaming agent with a mixing head at 15 to 50 ° C. according to a conventional method is used to form a hollow panel body composed of a surface material and a side frame material. It can be easily manufactured by injecting into a cavity, foaming and molding.

The surface material of the hollow panel body varies depending on the purpose of use of the heat insulating panel, but may be a metal or alloy plate such as aluminum, iron, stainless steel, a PVC steel plate, a structural plywood, or the like.
Glued laminated materials, such as an oriented strand board (OSB), are mentioned.

As the side frame material, a resin molded product such as PVC or ABS, wood or the like is generally used.

The size of the heat insulating panel of the present invention is not particularly limited, but is generally 30 to 150.
cm × 150 to 800 cm × thickness of about 2 to 20 cm.

[0048]

The present invention will be described more specifically below with reference to examples and comparative examples. In the following, “%” indicates “% by weight” unless otherwise specified.

Examples 1 to 4 and Comparative Examples 1 to 4 First, a mixture A was prepared according to the formulation shown in Table 1, and polyisocyanates A and B and, if necessary, a blowing agent C
Was prepared.

The raw materials used are as follows. Polyol A: m, p-phthalic acid-based polyester polyol manufactured by Toho Rika Kogyo Co., Ltd., hydroxyl value 430, acid value 8.9 mg-KOH / g Polyol B: o-phthalic acid-based polyester polyol manufactured by Toho Rika Kogyo Co., Ltd. , Hydroxyl value 300, acid value 1.0 mg-KOH / g Polyol C: Mannich-modified polyether polyol manufactured by Daiichi Kogyo Seiyaku Co., Ltd. Hydroxyl value 470 Flame retardant: "Phirol PCF" manufactured by Stoffer Japan KK Agent: "L5420" manufactured by Nippon Unicar Co., Ltd. Catalyst A: "Kaolyzer No. 1" manufactured by Kao Corporation Catalyst B: "Kaolyzer No. 3" manufactured by Kao Corporation Pentamethyldiethylenetriamine Catalyst C: "Kaolyzer No. 25" manufactured by Kao Corporation Reactive amine catalyst dimethyla Nohexanol (1 hydroxyl group in one molecule) Catalyst D: "B-15G" manufactured by Nippon Kagaku Sangyo Co., Ltd. Potassium 2-ethylhexylate Blowing agent A: "Diflon 141b" manufactured by Daikin Industries, Ltd. Dichloromonofluoroethane Blowing agent B: Water Blowing agent C: "HFC-134a" manufactured by Mitsui Fluorochemicals, Inc. 1,1,1,2-tetrafluoroethane Polyisocyanate A: Nippon Polyurethane Co., Ltd. crude diphenylmethane diisocyanate (NCO% 30. 2, pentanuclear or higher content in polyisocyanate: 24%, 4,4 ′ content in MDI: 99%) Polyisocyanate B: crude diphenylmethane diisocyanate (NCO% 31.4, manufactured by Sumitomo Bayer Urethane Co., Ltd.) 24% content of pentanuclear or higher in polyisocyanate, 4,4 'isomer in MDI 77%) As the panel body 1, as shown in FIG. 1, two surface materials: OSB (oriented strand board)
(910 mm x 2730 mm x 11 mm thickness) 2A, 2
B and a side frame material 3 (a square material having a thickness of 60 mm), a hollow portion (inner glue) 810 mm × 2600 mm × 60
mm. In the center of the long side of the side frame member 3, a raw material injection hole 3A is provided. This panel main body 1 was clamped by a high-pressure press machine and installed horizontally. Also,
The temperature of the surface materials 2A and 2B was kept at 30 ° C.

As a foaming machine, NR-20 manufactured by Toho Machinery Co., Ltd.
Using a 0-type PU high-pressure foaming machine, the blending liquid A and the polyisocyanate A or B, or in the case of using the blowing agent C, the foaming agent C as a third component is preliminarily mixed with the blending liquid A at normal temperature and foamed. The obtained isocyanurate-modified rigid polyurethane foam raw material was injected from the injection hole 3A at the center in the longitudinal direction of the panel body 1, and was taken out from the press 20 minutes after the injection.

The performance of the obtained heat insulating panel was evaluated by the following method, and the results are shown in Table 1.

Filling property: The surface material was peeled off 20 minutes after the injection,
The inside was observed.も の indicates that the raw material was filled to the end, and X indicates that there was an unfilled portion or a void portion.

Thickness shrinkage: The rate of dimensional change in the foam thickness direction after standing at room temperature for 24 hours with respect to 20 minutes after injection was measured. The dimensional change rate was an average value of the measured values at two points at the center and the end of the panel.

Surface test: foam core (thickness: 20 m)
m) by JI combustion tester manufactured by Toyo Seiki Seisakusho
A surface test based on SA1321 (heating time: 10 minutes) was performed.

[0056]

[Table 1]

Table 1 shows that the heat-insulating panel of the present invention exhibits excellent heat-insulating properties because of its excellent flame retardancy and filling properties and low shrinkage.

[0058]

As described in detail above, according to the heat insulating panel of the present invention, a raw material of isocyanurate-modified rigid polyurethane foam which has high heat insulating properties and airtightness, saves labor by constructing panels, and can shorten the construction period. The present invention provides a heat insulating panel obtained by injection-molding a heat insulating panel, the heat insulating panel having remarkably good flame retardancy and heat insulating property.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a panel main body used in Examples and Comparative Examples.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Panel main body 2A, 2B Surface material 3 Side frame material 3A Injection hole

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI E04B 1/80 E04B 1/80 V E04C 2/38 E04C 2/38 S // B29K 75:00 (72) Inventor Masafumi Ishii Kanagawa Bridgestone Yokohama Factory, 1 Kashio-cho, Totsuka-ku, Yokohama-shi

Claims (4)

[Claims] 1. A polyisocyanate component, a polyol component, a foaming agent, a catalyst, a foam stabilizer, and other auxiliaries in a hollow portion of a hollow panel body having a hollow portion composed of a surface material and a side frame material. A heat insulating panel obtained by injecting and molding an isocyanurate-modified rigid polyurethane foam raw material obtained by mixing and foaming a blended liquid comprising: a hydroxy compound, o-phthalic acid, m-phthalic acid, An acid value of 5.0 mg obtained by subjecting one or more polybasic acid components selected from the group consisting of p-phthalic acid and their derivatives to an esterification reaction.
5 KOH / g or more of polyester polyol compound
A heat insulating panel containing 0% by weight or more. 2. The heat insulating panel according to claim 1, wherein a reactive amine catalyst comprising an amine compound having at least one hydroxyl group in one molecule is used in an amount of 10% by weight or less based on the polyol component. 3. The polyisocyanate component according to claim 1, wherein the polyisocyanate component is a polyisocyanate compound represented by the following general formula (I), wherein the ratio of polymeric isocyanate of n ≧ 3 is 3 in the polyisocyanate compound.
Of the binuclear diisocyanates having less than 0% by weight and n = 0, 4,4′- represented by the following structural formula (II)
A heat insulating panel, wherein the proportion of methylene diisocyanate is 85% by weight or more. Embedded image 4. The method according to claim 1, wherein a gaseous blowing agent at normal temperature and normal pressure is used in an amount of 10% by weight or less based on the total of the polyol component and the polyisocyanate component. Insulation panel.