JPH1160782A - Thermal insulating board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject board for a laminate board material, apart from shrinkage and warpage and excellent in flameretardancy of foam by employing a specific polyol component and catalyst within a specific isocyanate index. SOLUTION: This board is obtained by blending (A) a polyisocyanate component, pref. that of the formula, (B) a polyol component (containing >=30 wt.% of polyester polyol component obtained by subjecting a hydroxy compound and one or more kinds selected from the group consisting of o-phthalic acid, n-phthalic acid, p-phthalic acid and the derivatives thereof to esterification reaction), (C) an expanding agent, and (D) a blended liquid of a catalyst (a reactive amine catalyst comprising an amine compound having one or more OH groups in one molecule is used in the ratio of >=10% based on the component B), foam-conditioning agent, and other auxiliary agent, by expanding the mixture into an isocyanurate modified rigid polyurethane foam, and by setting an isocyanate index based on the total of the component B and other compounds having ant active hydrogen to be 120 to 250 in case of laminating a surface material out the foam.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat insulating board useful as a panel material or a board material for a refrigerated or frozen warehouse or a detached house, and more particularly to a laminated board material and a siding excellent in heat insulation and flame retardancy. The present invention relates to a heat insulating board made of materials.

[0002]

2. Description of the Related Art In recent years, there has been an increasing demand for heat insulating and airtightness of construction panel materials and board materials for commercial warehouses, stores, and detached houses from the viewpoint of energy saving.

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.

[0004] For example, as a plate-like material used for heat insulation in a commercial warehouse or the like, a laminate board material formed by laminating non-combustible paper or gypsum face material on hard urethane foam,
There is a siding material obtained by laminating a metal facing material or a ceramic facing material. In recent years, demand for these laminated board materials and siding materials has been increasing due to the high heat insulating performance of rigid polyurethane foams, and the market for these heat insulating boards is expected to grow in the future.

[0005] Such a heat insulating board using a rigid polyurethane foam as a heat insulating material is generally prepared by mixing a polyisocyanate component with a compounded liquid obtained by mixing a polyol component, a foaming agent, a catalyst, a foam stabilizer and other auxiliaries. It is manufactured by a continuous foaming method in which paper, veneer plate, metal plate, gypsum board, and the like are laminated and molded on an isocyanurate-modified rigid polyurethane foam raw material obtained by foaming, and then cut into predetermined dimensions. A typical example of the molding method by continuous foaming is a double conveyor system in which a rigid polyurethane foam raw material is discharged from a mixing head onto a surface material sent out by a pair of upper and lower belt conveyors, and pressed and molded in a foaming process. According to this method, the dimensions of the product can be arbitrarily designed, and it can be integrally molded with the surface material in one step, and the productivity is high.

[0006]

A rigid polyurethane foam used as a heat insulating material for a heat insulating board such as a laminate board material or a siding material used in a warehouse or other applications has a long-term stable heat insulating property and airtightness. In addition to being able to hold, it is required to have high flame retardancy and not easily spread in the event of a fire.

In other words, 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 board 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 board.

[0008] In the case of a heat insulating board formed by continuous foam molding, shrinkage and curing properties of the raw material of the rigid polyurethane foam are also important. That is, if the rigid polyurethane foam raw material has a large shrinkage, the thickness of the board is reduced after molding, or the entire board is warped, which causes a quality problem. Further, if the rigid polyurethane foam has poor curing properties, the cut surface will be flaky when cut immediately after molding, and small edge shrinkage will occur, resulting in an increase in the product defect rate.

The present invention has been made in view of the above circumstances, and is a laminate board material or a siding material (hereinafter, simply referred to as a "heat insulation board") obtained by continuous foam molding of a rigid polyurethane foam. It is an object of the present invention to provide a high-quality, high-performance heat insulating board which is excellent in flame retardancy of a foam, and has little shrinkage or warpage.

[0010]

The heat insulating board of the present invention comprises:
Polyisocyanate component, polyol component, foaming agent,
A heat insulating board obtained by laminating a surface material on an isocyanurate-modified rigid polyurethane foam obtained by mixing and foaming a mixed solution obtained by mixing a catalyst, a foam stabilizer and other auxiliaries, wherein the polyol component is a hydroxy compound And a polyester polyol compound obtained by subjecting one or more polybasic acid components selected from the group consisting of o-phthalic acid, m-phthalic acid, p-phthalic acid and their derivatives to an esterification reaction ( Hereinafter referred to as “phthalic acid-based polyester polyol”).
An isocyanate index of 120 to 250 with respect to the total amount of the polyol component and other compounds having active hydrogen, and a reactive amine catalyst comprising an amine compound having one or more hydroxyl groups in one molecule, It is characterized in that 10% by weight or less is used.

In the present invention, the above-mentioned phthalic acid-based polyester polyol and the reactive amine catalyst are used in combination within the range of the above-mentioned specific isocyanate index.
Significantly good flame retardancy can be obtained while preventing shrinkage and warpage.

In the present invention, the polyisocyanate component is a polyisocyanate compound represented by the following general formula (I).
The ratio of the polymeric isocyanate of n ≧ 3 is less than 30% by weight (hereinafter, this ratio is referred to as “the content of five or more nuclei in the polyisocyanate”), and n =
0 among the dinuclear diisocyanates represented by the following structural formula (II)
The ratio of 4,4′-methylene diisocyanate (hereinafter, referred to as “4,4′-MDI”) represented by the following formula (hereinafter, this ratio is referred to as “4,4′-form content in MDI”): 85
% Or more (hereinafter, such a polyisocyanate is referred to as a “nucleus-controlled polyisocyanate”), and preferably within the range of the specific isocyanate index, together with the phthalic acid-based polyester polyol and the reactive amine catalyst, By using such a polyisocyanate component in combination, even better flame retardancy can be obtained.

[0013]

Embedded image

Furthermore, it is preferable to use a blowing agent which is a gas at normal temperature and 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 blowing agent, the shrinkage can be suppressed to a small value, and warpage can be prevented.

[0015]

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 board of the present invention will be described.

The polyol component used in 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. It contains 30% by weight or more of a phthalic acid-based polyester polyol obtained by subjecting a polybasic acid component to an esterification reaction.

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

If the content of the phthalic polyester polyol in the polyol component is less than 30% by weight, sufficient flame retardancy cannot be obtained. The content of the phthalic acid-based polyester polyol in the polyol component is preferably 60% by weight.
As described above, the content is more preferably 70% by weight or more. In particular, by using 70% by weight or more of the phthalic acid-based polyester polyol, a stable and reliable flame retardant effect can be obtained.

Examples of the hydroxy compound forming the phthalic acid-based polyester polyol include ethylene glycol, diethylene glycol, phenol, and a compound 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 phthalic acid-based polyester polyol according to the present invention is a ratio as pure phthalic acid-based polyester polyol, and is a hydroxy compound contained in an unreacted state in a product of an ester synthesis reaction. And polybasic acid components and other additives are not included.

In the present invention, as the polyol component, in addition to the phthalic acid-based polyester polyol, a polyol such as Mannich-modified polyol, ethylenediamine, tolylenediamine, sucrose, aminoalcohol, diethyleneglycol, etc., as long as the object of the present invention is not impaired. The compound may be used in an amount of 30% by weight or less in the polyol component.

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 at least 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 according to the present invention preferably has a pentanuclear or higher content in the polyisocyanate of 5 to 25% by weight, and if the content is less than 5% by weight, the synthesis process is complicated and at present the 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.

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 can be 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.

In the present invention, the polyisocyanate component has an isocyanate index in the range of 120 to 250,
If the isocyanate index is less than 120, it is difficult to achieve good flame retardancy, and if it is more than 250, it is difficult to suppress shrinkage and warpage and to improve cure properties. The isocyanate index of the polyisocyanate component is preferably in the range of 140 to 200, more preferably 1
It is in the range of 50 to 180, and within this range, good flame retardancy, shrinkage, and cure can be achieved simultaneously.

The isocyanate index is a value based on the total amount of other active hydrogen-containing compounds such as a polyol component and water.

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 varies mainly depending on the molding conditions, but is not more than 10% by weight, preferably not more than 5% by weight, more preferably not more than 0.1 to 5% by weight, based on the polyol component. % By weight. The use amount of the reactive amine catalyst is 10% by weight based on the polyol component.
Exceeding this is undesirable because the flame retardant performance is rather reduced.

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 foaming agent, dichloromonofluoroethane, pentafluoropropane, water or the like, preferably dichloromonofluoroethane is 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 used 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 depending on 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 phthalic acid-based polyester polyol and the reactive amine catalyst under the specific isocyanate index.
Further, by using a nucleus controlling polyisocyanate and / or a low-boiling-point blowing agent in combination, even better characteristics can be obtained.

The heat insulating board of the present invention comprises a blended component obtained by mixing a foaming agent, a catalyst, a foam stabilizer and other auxiliaries with a polyol component, a polyisocyanate component, and, when a low boiling foaming agent is used, the low boiling point foaming agent. Continuous foam molding in which a surface material is laminated on an isocyanurate-modified rigid polyurethane foam obtained by mixing and foaming the third component of a foaming agent with a mixing head at 15 to 50 ° C according to a conventional method, and pressing with a belt conveyor or the like. It can be easily manufactured by a method or the like.

The surface material of the heat insulating board of the present invention varies depending on the purpose of use of the heat insulating board.
Soft surface materials such as kraft paper and asphalt felt,
Hard surface materials such as gypsum board, wood wool cement board, plywood and the like can be mentioned.

Although the size of the heat insulating board of the present invention is not particularly limited, it is generally 30 to 200.
cm × 150-800 cm × thickness 1-20 cm.

[0044]

The present invention will be described more specifically below with reference to examples and comparative examples. In the following, “%” other than the value of the shrinkage indicates “% by weight”.

Examples 1 to 3 and Comparative Examples 1 to 3 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 B
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 Polyol B: Mannich-modified polyether polyol manufactured by Daiichi Kogyo Seiyaku Co., Ltd., hydroxyl value 470 Flame retardant: Stoffer Japan Co., Ltd. ) "Fairol PCF" Foam stabilizer: "L5420" manufactured by Nippon Unicar Co., Ltd. Catalyst A: "Kaolyzer No. 25" manufactured by Kao Corporation Reactive amine catalyst dimethylaminohexanol (having 1 hydroxyl group in one molecule) Catalyst B: "Kaolyzer No. 1" manufactured by Kao Corporation Tetramethylhexamethylenediamine Catalyst C: "B-15G" manufactured by Nippon Chemical Industry Co., Ltd. Potassium 2-ethylhexylate Blowing agent A: manufactured by Daikin Industries, Ltd. "DAIFRON 141b" Dichloromonofluoroethane Blowing agent B: Mitsui Fluorochemicals, Inc. “HFC-134a” 1,1,1,2-tetrafluoroethane polyisocyanate A: Nippon Polyurethane Co., Ltd. crude diphenylmethane diisocyanate (NCO% 30.2, pentanuclear or higher content in polyisocyanate 24% content) , 4,4′-form content in MDI 99%) Polyisocyanate B: Sumitomo Bayer Urethane Co., Ltd. crude diphenylmethane diisocyanate (NCO% 31.4, pentanuclear or higher content in polyisocyanate 24%, MDI As shown in FIG. 1, the injection mold 1 for the raw material includes two aluminum surface materials (250 mm × 650 mm × 5 mm thick) 2A and 2B, Side frame material 3 (25mm thick)
The cavity (inner) 200 mm x 600
mm × 25 mm was used. The surface material 2A has a structure that can be opened and closed. The mold 1 was placed horizontally, and the temperature of the surface materials 2A and 2B was maintained at 30 °.

Formulation A and polyisocyanate A or B
Alternatively, when the blowing agent B is used, the blowing agent B is further mixed as a third component at room temperature in advance with the mixture A, and the obtained isocyanurate-modified rigid polyurethane foam raw material is immediately placed in the center of a horizontally placed mold. , And the surface material 2A was closed and pressed with a clip. Then, after 10 minutes, the mold was released, and the performance of the obtained heat insulating board was evaluated by the following method. The results are shown in Table 1.

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

Curability: Immediately after releasing the obtained heat-insulating board, the heat-insulating board was cut into two equal parts with a rough cutting knife, and the cross section was observed.
A sample having a smooth cross-section was indicated by "O", and a sample having a raised and uneven portion was indicated by "X".

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.

[0051]

[Table 1]

Table 1 shows that the heat insulating board of the present invention has excellent foam flame retardancy, low shrinkage, and good curing properties.

[0053]

As described above in detail, according to the heat insulation board of the present invention, the heat insulation board is obtained by continuous foam molding of an isocyanurate-modified rigid polyurethane foam having high heat insulation and airtightness, and has remarkable flame retardancy. A high-quality, high-performance heat insulating board which is favorable, has a small shrinkage rate, is excellent in curing properties, and thus has a good product yield.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an injection mold used in Examples and Comparative Examples.

[Explanation of symbols]

 1 type 2A, 2B surface material 3 side frame material

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI E04B 1/94 E04B 1/94 T // B32B 27/40 B32B 27/40

Claims (3)

[Claims] A surface material is applied to an isocyanurate-modified rigid polyurethane foam obtained by mixing and foaming a mixture of a polyisocyanate component and a polyol component, a foaming agent, a catalyst, a foam stabilizer and other auxiliaries. In a heat insulating board obtained by laminating, the polyol component comprises a hydroxy compound and one or more polyolefins selected from the group consisting of o-phthalic acid, m-phthalic acid, p-phthalic acid and derivatives thereof. It contains at least 30% by weight of a polyester polyol compound obtained by an esterification reaction with a basic acid component, has an isocyanate index of 120 to 250 with respect to the total amount of the polyol component and other compounds having active hydrogen, and A reactive amine catalyst comprising an amine compound having at least one hydroxyl group, Then 1
A heat insulating board characterized by using 0% by weight or less. 2. The polyisocyanate component according to claim 1, wherein the polyisocyanate component is a polyisocyanate compound represented by the following general formula (I):
The proportion of the polymeric isocyanate of n ≧ 3 is less than 30% by weight, and the proportion of 4,4′-methylene diisocyanate represented by the following structural formula (II) is 85 among the binuclear diisocyanates of n = 0. Insulation board characterized by not less than weight%. Embedded image 3. The heat insulating board according to claim 1, wherein a blowing agent which is gaseous at normal temperature and normal pressure is used in an amount of not more than 10% by weight based on a total of the polyol component and the polyisocyanate component.