JPH04120140A - Production of foam material for panel, foam compressed material for panel and panel board - Google Patents

Abstract

PURPOSE:To obtain the title material easy to compress or deform, restorable in its shape by reheating, and capable of giving lightweight, highly rigid panel boards through curing in the presence of water under heating, by reaction of a polyol component with an excess amount of isocyanate component in the presence of water and/or an organic foaming agent. CONSTITUTION:A polyol component containing 3.0-50wt.%, based on the base polyol, of a bifunctional chain extender is reacted with an excess amount, compare to the reaction equivalent, of an isocyanate component in the presence of water and/or an organic foaming agent, thus giving the objective rigid or semi-rigid foam material for panels. A compressed material obtained by heating the present foam material to 130-220 deg.C followed by compression is reheated to 130-220 deg.C to restore the thickness followed by feeding water and then curing under heating, thus giving the other objective panel board.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is applicable to lightweight, high-rigidity panels, heat insulation panels, vibration damping/sound insulation panels, complex shaped panels, etc. used in the fields of housing/building materials, automobile interior materials, etc. The present invention relates to a foam material for panels used as a new core material for easily manufacturing various functional panels, a compressed foam material for panels, and a method for manufacturing a new panel board using the same.

[Conventional technology] A foam material with a high loss modulus, such as a lightweight foam such as hard urethane foam or styrene foam, or a semi-rigid foam containing asphalt, is used as the core material, and rigidity is imparted to the core material. For decorative purposes, various panels with a sandwich structure are made by laminating and pasting reinforcing sheet materials such as glass fiber mats and non-woven fabrics, rigid plates such as iron plates, and skin materials such as vinyl chloride cloth on both sides of the core material using adhesives. Although manufacturing methods have been known for a long time and are not particularly new techniques, these methods have the following problems.

■When manufacturing lightweight, highly rigid panels, the core material foam used is often a lightweight foam slice board with a thickness that matches the thickness of the panel, but because it is bulky, it is difficult to transport and store the material. It occupies a large volume and is not only costly but also inefficient.

■When manufacturing complex-shaped panels such as steel plates with a sandwich structure of rigid plates, conventionally a semi-rigid foam was press-compressed from both sides with rigid plates to create a sandwich structure, which required a complicated compression device.

[Problems to be Solved by the Invention] An object of the present invention is to provide a panel foam material, a panel foam compression material, and a method for manufacturing a panel board that solve the above-mentioned drawbacks of the conventional panel core foam. shall be.

[Means for Solving the Problems] Therefore, the inventors of the present invention conducted extensive research to solve these process problems, and found that the foam is hard or semi-hard under normal temperature conditions, but becomes soft under high temperature conditions. Not only is it easily compressed and deformed, but the compressed and deformed foam completely returns to its original size and shape when heated again, and when reacted with water under heating, it hardens and permanently deforms. The present invention was accomplished by discovering a foam material shown in the figure.

The rigid or semi-rigid foam material for panels of the present invention is produced by combining a polyol component containing 3.0 to 50% by weight of a bifunctional chain extender and an isocyanate component based on the base polyol in the presence of water and/or an organic blowing agent. The isocyanate component is reacted in excess of the reaction equivalent, and the foam material for the panel, which is polyurethane/polyurea resin foam or polyurethane resin foam, is heated to 130°C to 220°C to soften it, and then immediately The compressed foam material, which is compressed and deformed into a sheet of uniform thickness by cold pressing, has good storage stability at room temperature and is flexible enough to be easily rolled up into a roll. However, this sheet simply returns to its original thickness when heated (because it is a very soft foam, it can be easily shaped by placing it in a complex-shaped mold with a deep drawing pattern and cold pressing it. be able to.

Furthermore, at this time, water was supplied to the foam by spraying, etc., and the foam was molded by cold pressing, which caused so-called permanent deformation that did not return to shape when heated again.
In combination with a reinforcing material, a sheet molded body suitable for automobile molded ceiling materials, etc. is provided. In addition, as another method, this compressed foam material is sandwiched between two rigid plates such as iron plates, and by heating the whole, the compressed foam material returns to its original thickness, creating a sandwich structure of rigid plates - foam - rigid plates. You can also get the body easily. At this time, if the foam material itself has a large loss modulus, the resulting sandwich structure can be applied as a vibration damping and soundproofing panel, for example, to the flooring of an automobile.

The polyol component used in the present invention is based on the base polyol commonly used in polyurethane production.
It contains 0 to 50% by weight of a bifunctional chain extender.

Examples of the base polyol used in the present invention include dihydric alcohols such as ethylene glycol, propylene glycol, 1,4-butanediol, and diethylene glycol, trihydric alcohols such as glycerin, trimethylolpropane, pentaerythritol, sorbitol, and sucrose. Polyhydric alcohols such as tetrahydric or higher alcohols, or addition polymerization of alkylene oxides such as propylene oxide and ethylene oxide to these polyhydric alcohols, and addition polymerization of alkylene oxides to aliphatic or aromatic polyamines and alkanolamines. Ether polyols, so-called polymer polyols obtained by graft polymerizing monomers having vinyl groups to polyether polyols, or polyester polyols obtained by condensation polymerization of polybasic acids and polyhydric alcohols, etc. - For boat fishing urethane foam. One or a combination of two or more of the polyol components used may be used.

Furthermore, in order to clearly exhibit the characteristics of this foam, which plays a central role in the present invention, a polyol obtained by addition polymerizing a large amount of ethylene oxide to the above-mentioned polyhydric alcohol, aliphatic or aromatic polyamine, or alkanolamine is added. It is preferable that the foam has a foam-breaking effect.

In the present invention, one of the above-mentioned base polyols includes a bifunctional phenolic chain extender such as bisphenol A, a bifunctional aromatic amine chain extender such as diphenylmethanediamine, and a bifunctional chain extender that is a derivative thereof. Or it is important to add two or more of them.

These bifunctional chain extenders are added as one of the polyol components, but in order to more clearly exhibit the effects of the present invention, 3.0 to 50% by weight, preferably 5.0 to 30% by weight, based on the base polyol. Weight % is required. If the amount of the bifunctional chain extender is less than 3.0% by weight, the foam will have little thickness restoration upon heating; The shrinkage phenomenon becomes severe, making it impossible to obtain a foam material with good dimensional accuracy.

Further, in order to impart a large loss modulus to the foam itself, it is possible to add asphalt or the like, but this does not go beyond the scope of the present invention.

In addition, general aliphatic or aromatic isocyanates or mixtures thereof are used as the isocyanate component, and if necessary, preforms having terminal -NGO groups obtained by partially reacting these isocyanates with polyols may be used. Polymers can also be used.

The mixing ratio of the polyol component and the isocyanate component is such that there is a large amount of unreacted isocyanate component in the foam made by using an excess of isocyanate component (reaction equivalent) than the amount of isocyanate component that chemically reacts with the polyol component used (reaction equivalent). so that it remains.

When water is used as a blowing agent, there is a large amount of unreacted isocyanate component in the foam made by using a larger amount of isocyanate component than the polyol component used and the amount of isocyanate component that reacts chemically equivalently with water (reaction equivalent). so that it remains.

The amount of the isocyanate component used is preferably 1.2 to 5 times, preferably 1.5 to 2.5 times the reaction equivalent.

In addition, organic foaming agents such as water and methylene chloride are added to form the obtained polyurethane resin or polyurethane/polyurea resin into a foam. All agents can be used, and the type is not limited. Furthermore, the amount may be arbitrarily set depending on the intended use of the final product, and is not particularly limited.

Further, in foaming, catalysts, surfactants, etc. can also be used as necessary. The type and amount of additives used can be the same as those used for general urethane foam.
Not particularly limited.

The raw material cream formulated in this way may be foamed continuously using an ordinary multi-component foaming machine or foamed batchwise, but it may be foamed in blocks, and after foam hardening, a predetermined Thick slices are convenient for the present invention.

The rigid or semi-rigid foam constant thickness plate thus obtained becomes soft when heated to 130°C or higher, and becomes like a soft foam when heated to 160°C or higher. Furthermore, spray water on the foam material in this soft foam state.
When pressurized in a deep drawing mold at 0°C or higher, not only can a deep-drawn molded product with good mold conformability be obtained, but also the water sprayed onto the foam material can remove unreacted isocyanate remaining in the foam material. Reacts with NGO groups,
The foam changes to a thermosetting type, and the shaped molded product shows good permanent deformation without returning to the mold even when reheated.

In addition, the foam material was heated to 130℃ without spraying water.
A sheet-shaped foam compressed material obtained by heating to the above temperature and then cold pressing to a thickness of 1% to 1% of the original thickness and compressing at a constant thickness easily returns to the original thickness by reheating.

This compressed foam material is a sheet with good storage stability at room temperature, and is flexible enough to be easily rolled up.

The following range of heating temperature conditions is recommended in order to more effectively exhibit the effects of the present invention.

Rigid or semi-rigid plates that have been formed or sliced to a certain thickness soften at temperatures above 130°C, and at temperatures above 160°C they become as if they were soft foam, but at temperatures above 220°C, the foam undergoes thermal deterioration. It becomes brittle as well as discolored.

Therefore, the heating temperature to easily perform constant thickness compression is 13
The temperature is 0°C or more and 220°C or less, preferably 160°C or more and 200°C or less.

Although the heating time varies depending on the thickness of the formed or sliced plate and the heating temperature, excessively long heating times should be avoided even if the heating temperature is low (even if the heating temperature is low, as there is a risk of deterioration of the form).

Furthermore, it is of course possible to use this constant thickness foam material as a laminate in which nonwoven fabric or skin material is adhered to both sides using a hot-melt type adhesive, and in that case, these laminate configuration conditions must be met in advance. A laminated sheet that has been compressed to a constant thickness can easily return to a thickness equivalent to the original foam material thickness by reheating, but the reheating conditions at this time are determined not only by the heat resistance temperature of the foam but also by the heat resistance temperature resistance of the nonwoven fabric and skin material. It goes without saying that the heating temperature and heating time should be taken into account.

The present invention will be described in detail below with reference to Examples, but the present invention is not limited to these Examples.

Example 1 Mix raw materials according to the formulation shown in Table 1 and obtain thickness x width x length = 3
A block of 00 x 300 x 300 mm was created. In the formulations shown in Table 1, the amount of isocyanate component relative to the amount of water and polyol component was twice the chemical equivalent.

After reaction and hardening, slice this block into thickness x width x
A plate-like foam material with a length of 10 x 250 x 250 mm was cut out. The specific gravity of this plate material is 0.

040 open-celled rigid foam.

Table: When this plate-shaped foam material was placed in an oven at 180°C for 1 minute, it changed to a very soft foam, so it was compressed to a thickness of 3 mm using a press at 60°C, and after 1 minute, the press pressure was released. When you take out the form 3
A sheet-like compressed foam material with a thickness of mm was obtained.

When this sheet-like compressed foam material is reheated to 180℃, the thickness of the original sliced plate (10 m
returned to m). Furthermore, water was sprayed on the heated foam whose thickness had been restored, and when it was immediately set in a deep drawing mold maintained at a temperature of 65°C and pressed for 30 seconds, it showed very good mold conformability and a deep drawn product was formed. Obtained.

This molded product was then placed in an oven at 130℃ for 30 minutes.
It did not lose its shape even after being poured for a minute, and showed good high-temperature dimensional stability.

Example 2 A high tensile strength nonwoven fabric (Unitika Spunbond 71000WSO; polyester type, basis weight 1o0g/rrf, longitudinal tensile strain crab 20kg
/3 cm) were laminated and pressed for 20 seconds using a 150°C hot press to obtain a nonwoven fabric-compressed foam material-nonwoven fabric laminated product with a total thickness of 3 mm.

When this laminate is reheated to 180°C, after 30 seconds it becomes a double-sided non-woven laminate with the same thickness (10mm) as the original sliced board, and then immediately sprayed with water while still hot, it is heated to 65°C. When set in a drawing mold and pressed for 30 seconds, a deep-drawn product with very good mold conformability and high rigidity was obtained. This molded product is then
Even after being placed in an oven at 30°C for 30 minutes, it did not lose its shape and exhibited good high-temperature dimensional stability.

Dog Example 3 The same formulation as Example 1 with an additional 100% asphalt component.
The added raw materials were mixed and foamed to create a block with thickness x width x length = 300 x 300 x 250 mm.

After reaction and curing, this block was sliced to cut out a plate-like foam material with thickness x width x length = 10 x 250 x 250 mm. This plate was an open-cell semi-rigid foam with a specific gravity of 0.050 and a loss modulus of elasticity. It was big.

The behavior of this foam during heating and cold pressing is shown in Example 1.
, 2, and in particular, 1.0 mm on both sides of the form.
When the damping effect of the laminated structure made of thick steel plates bonded together was measured using the -point vibration method, the loss coefficient η = 0.65, making it a good damping composite structural board, making it suitable as a vehicle flooring material. It was something.

Comparative Example 1 Example 1 was prepared by mixing raw materials with the composition shown in Table 1 and containing 2.0 parts by weight of chain extender (the amount of insinate component is 2.5 times the chemical equivalent to the amount of water and polyol component). A foamed block was made in the same manner as above, and the board was cut out. When this foam plate material is placed in an oven at 180℃ for 1 minute, it changes to a very soft foam, and
When the foam was compressed to a thickness of 3 mm using the press C, and after 1 minute the press was released and the foam was taken out, a compressed foam with a thickness of 3 mm was obtained. Not only did it not return to its thick texture, but it also did not return to a soft foam state.

Comparative Example 2 The same procedure as in Example 1 was carried out by mixing raw materials with the composition shown in Table 1 and containing 55 parts by weight of chain extender (the amount of isocyanate component relative to the amount of water and polyol component is 1.45 times the chemical equivalent). When the block was foamed, it became a closed-cell block, which shrunk significantly after cooling, making it impossible to obtain a good plate material.

[Effects of the Invention] The foam material of the present invention is a hard or semi-hard foam under normal temperature conditions, but it softens under high temperature conditions and can be easily compressed and deformed. When the foam is heated again, it completely returns to its original size and shape, and when reacted with water under heating, it hardens and exhibits permanent deformation.

Therefore, the compressed foam material is not only suitable as a core material for lightweight and highly rigid panels, but is also economical and efficient because it has a small volume and occupies a small volume during transportation and material storage.

Claims (1)

[Claims] 1) A polyol component containing 3.0 to 50% by weight of a bifunctional chain extender based on the base polyol is reacted with an isocyanate component in the presence of water and/or an organic blowing agent. Rigid or semi-rigid foam material for panels made by reacting in excess of equivalent amount. 2) A polyol component containing a bifunctional chain extender of 3.0 to 50% by weight based on the base polyol and an isocyanate component are combined in the presence of water and/or an organic blowing agent such that the isocyanate component is present in excess of the reaction equivalent amount. A rigid or semi-rigid foam compressed material for panels made by heating and compressing foam reacted at 130°C to 220°C. 3) The rigid or semi-rigid foam compressed material for panels according to claim 2, wherein a reinforcing sheet material or a skin material is adhered to the surface. 4) A polyol component containing a bifunctional chain extender of 3.0 to 50% by weight based on the base polyol and an isocyanate component are combined in the presence of water and/or an organic blowing agent such that the isocyanate component is present in excess of the reaction equivalent amount. The compressed material obtained by heating and compressing the reacted foam at 130°C to 220°C is reheated to 130°C to 220°C to restore the thickness, and then water is supplied to heat and harden the material. A method for manufacturing panel boards. 5) The method for manufacturing a panel board according to claim 4, wherein the compressed material has a reinforcing sheet material or a skin material adhered to the surface thereof. 6) A polyol component containing a bifunctional chain extender in an amount of 3.0 to 50% by weight based on the base polyol and an isocyanate component are mixed in the presence of water and/or an organic blowing agent such that the isocyanate component is present in excess of the reaction equivalent amount. A compressed foam material made by heating the reacted foam to 130°C to 220°C and compressing it is sandwiched between two rigid plates and heated to 130°C.
A method for producing a sandwich structure panel board, which comprises reheating to ~220°C to restore the thickness of the compressed foam material, and then supplying water to heat and harden it.