JPH04303636A - Molded ceiling material - Google Patents

Abstract

PURPOSE:To provide a sound absorbing material which satisfactorily realizes acoustic absorption performance in the range of a low frequency and prevents dirt of a skin material. CONSTITUTION:A layer of a film single layer and having no permeability is held by two honeycomb plates and, on the surface of the honeycomb plate at the side of the vehicle interior, a resin cotton and surface layer impregnated with phenol resin provided via an acoustic absorption layer and felt is provided on the other surface.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a molded ceiling material, and more specifically, it has excellent sound absorption properties in the low frequency range against noise from outside and outside of a vehicle interior, and also prevents the surface skin material of the molded ceiling material from becoming dirty with dust, etc. This invention relates to a molded ceiling material that can prevent this.

0002

2. Description of the Related Art Conventionally, for example, molded ceiling materials have been used as ceiling materials for automobiles, in which felt is press-molded either alone or integrally with a non-woven skin material. Recently, molded ceiling materials have been manufactured by sandwiching honeycomb plates with felt, integrating them with a nonwoven skin material, and molding them under heat and pressure.

[0003] However, these molded ceiling materials are desired to further improve their sound absorption properties against noise in the low frequency range, and there has been a problem in that the surface skin material of the molded ceiling materials becomes dirty with dust inside the vehicle interior. .

0004

[Problems to be Solved by the Invention] An object of the present invention is to realize a molded ceiling material that has excellent sound absorption properties in the low frequency range and also prevents dirt on the surface skin material of the molded ceiling material mainly caused by dust. At the point.

[0005]

[Means for Solving the Problem] In order to solve the problem, the inventors of the present invention have conducted extensive research and have developed a structure in which a non-permeable layer is sandwiched between two honeycomb plates. The summary consists of the following items.

[0006] The non-breathable layer is sandwiched between two honeycomb plates, and the surface of the honeycomb plate on the inside side of the vehicle is integrated with the resin cotton impregnated with thermosetting resin and the skin layer through the sound absorbing layer, and the other A molded ceiling material characterized by its surface being integrated with felt.

[0007] The non-breathable layer is sandwiched between two honeycomb plates, and the surface of the honeycomb plate on the inside side of the cabin is integrated with the resin cotton impregnated with thermosetting resin and the skin layer through the sound absorbing layer, and the other A molded ceiling material characterized in that the surface is also made of resin cotton impregnated with thermosetting resin and integrated with the skin layer through a sound absorbing layer.

[0008] The non-breathable layer is sandwiched between two honeycomb plates, and the surface of the honeycomb plate on the inside side of the cabin is integrated with the resin cotton impregnated with thermosetting resin and the skin layer through the sound absorbing layer, and the other A molded ceiling material characterized in that the surface is made of resin cotton impregnated with thermosetting resin and integrated with a skin layer.

The non-breathable layer 1 sandwiched between two honeycomb plates 2, which is an essential component of the present invention, may be a single layer of a non-breathable film 1' or a non-woven fabric 1''.
A multi-layered film sandwiched between two films 1' can be used. In this case, in order to improve the adhesiveness with the honeycomb plate 2, it is preferable that the surface in contact with the honeycomb plate is made of an adhesive layer.

The resin cotton 6, which is an essential component of the present invention, is made by lightly compression molding resin fibers, and examples thereof include polyester fibers, polyamide fibers, polyvinyl alcohol fibers, and polyvinyl chloride fibers.

[0011] As the skin layer 7, it is essential that the weight can be reduced compared to when felt is used, and that it has shape retention,
It is preferable to use a material that also has a surface reinforcing function, such as glass paper, glass mat, paper, etc.

It is essential that the resin cotton 6 and the skin layer 7 be impregnated with a thermosetting resin in advance. The thermosetting resin is a phenol resin, a polyester resin, a urethane resin, a melamine resin, a paraffin resin, etc., and the preferred impregnation method is dipping or coating. The amount of thermosetting resin impregnated into the resin cotton needs to be sufficient to ensure adhesion with the honeycomb plate 2, and is preferably about 1 to 100% of the weight of the resin cotton. The amount of impregnation may be selected depending on whether the agent is applied or not.

[0013] The honeycomb plate 2 is preferably made of a paper material such as kraft paper, K-liner paper, or cardboard, or a plastic material having a honeycomb structure from the viewpoint of moldability.

The felt 4 integrated on one side of the honeycomb plate 2 is mainly made of one or more discontinuous fiber materials of animal origin, vegetable origin, or synthetic resin and a binder such as thermosetting resin. It is what it is.

The sound absorbing layer 5 interposed between the resin cotton 6 and the honeycomb plate 2 is made of a foam material such as polystyrene, polypropylene, polyurethane, etc., which is about half the thickness of conventionally used felt.

The areal density of each constituent material is 30 to 150 g/m2 for the skin layer 7, 30 to 100 g/m2 for the resin cotton 6, and 5 to 100 g/m2 for the sound absorbing layer 5 when impregnated with thermosetting resin.
The weight of the conventionally used felt 4 is about 350 to 1000 g/m2.

The adhesive surface between the honeycomb board 2 and the felt 4, the sound absorbing layer 5 or the resin cotton 6 may be formed by heating and pressure without applying any adhesive, but the cells of the honeycomb board 2 may be hot-melted in advance. Alternatively, it is preferable to use the coating type adhesive 3 in terms of making the adhesion stronger.

As a method for integrally molding each of the constituent materials, for example, a resin cotton 6 and a skin layer 7 are integrally formed on one side of the honeycomb plate 2 via a sound absorbing layer 5, and felt is formed on the other side. When the honeycomb plate 2 is placed between the honeycomb plates 2 and 4, the honeycomb plate 2 is placed between
A condition of 00 kg/cm2 is preferable.

[0019]

EXAMPLES Examples will be given below to provide a more detailed understanding of the present invention. Naturally, the present invention is not limited to the following examples.

[0020]

[Example 1] Resin cotton made of polyester fibers and a skin layer made of glass paper were integrated, impregnated in phenol resin, and dried to form an integrated product. A non-breathable film was placed between two cardboard honeycomb boards, and a 500 g/m2 bulky nonwoven fabric was placed on one side of the honeycomb board, and a 250 g/m2 urethane foam material was placed on the other side. The above-mentioned integrated product of the resin cotton and the skin layer was pressure-molded at 200° C. for 45 seconds at a pressure of 5 kg/cm 2 to obtain a ceiling material 1.

[0021]

[Example 2] A resin cotton made of polyvinyl chloride fiber and a skin layer made of glass paper were integrated, impregnated in a phenol resin, and then dried to form an integrated product. A non-breathable layer consisting of three layers of film, nonwoven fabric, and film is placed between two honeycomb boards made of cardboard, and the above resin cotton is placed on one side of the honeycomb board through a 250 g/m2 felt. and the integrated epidermal layer, and the other side is 250g/m2
The same integrated product of resin cotton and skin layer was heated at 200°C for 45 seconds at 5kg/cm2 through the urethane foam material.
The ceiling material 2 was obtained by pressure molding and integrating under the following conditions.

[0022]

[Example 3] A resin cotton made of polyvinyl chloride fiber and a skin layer made of glass paper were integrated, impregnated in a phenol resin, and then dried to form an integrated product. A non-breathable layer consisting of three layers of film, nonwoven fabric, and film is sandwiched between two honeycomb boards made of cardboard, and on one side of the honeycomb board, the above-mentioned integrated product of the resin cotton and the skin layer is placed. On the other side, the above-mentioned integrated resin cotton and skin layer was heated at 200°C for 45 seconds at 5 kg/cm2 through a 250 g/m2 felt.
The ceiling material 3 was obtained by pressure molding under the conditions of m2 and integrating.

[0023]

[Comparative example] 500 ml on one side of a cardboard honeycomb board
g/m2 felt, and the other side is 500 g/m2.
After providing the felt and the non-woven fabric skin material No. 2, they were pressure-molded at 200° C. for 1 minute at a pressure of 5 kg/cm 2 and were integrated to obtain a ceiling material 4.

[0024]

[Test method] Low frequency (250H) of ceiling materials 1 to 4
The sound absorption coefficient at z) was measured by the reverberation chamber method. Furthermore, ceiling materials 1 to 4 were attached to the ceiling, and after traveling 10,000 m, dirt on the surface was visually observed.

[0025]

[Result] The sound absorption coefficient of ceiling material 1 is 0.6 (250Hz)
There was no stain on the skin material. The sound absorption coefficient of ceiling material 2 was 0.6 (250 Hz), and there was no stain on the skin material. The sound absorption coefficient of the ceiling material 3 was 0.6 (250 Hz), and there was no stain on the skin material. The sound absorption coefficient of ceiling material 4 is
0.5 (250Hz), and the surface material was slightly dirty.

[0026]

[Effects of the Invention] The ceiling material according to the present invention exhibits satisfactory sound absorption performance in the low frequency range, and is also able to prevent staining of the skin material.

[0027]

[Brief explanation of drawings]

FIG. 1 is a sectional view of a ceiling material according to the present invention.

FIG. 2 is a sectional view of a ceiling material according to the present invention.

FIG. 3 is a sectional view of a ceiling material according to the present invention.

[Explanation of symbols]

1’ film 1” non-woven fabric 1. Non-breathable layer 2 Honeycomb board 3. Adhesive 4 Felt 5 Sound absorption layer 6 Resin cotton 7 Epidermal layer

Claims (3)

[Claims] [Claim 1] A non-breathable layer is sandwiched between two honeycomb plates, and the surface of the honeycomb plate on the inside side of the vehicle is integrated with resin cotton impregnated with a thermosetting resin and a skin layer through a sound absorbing layer. , a molded ceiling material characterized by having the other side integrated with felt. [Claim 2] A non-breathable layer is sandwiched between two honeycomb plates, and the surface of the honeycomb plate on the inside side of the vehicle is integrated with resin cotton impregnated with thermosetting resin and a skin layer through a sound absorbing layer. A molded ceiling material characterized in that the other side is also integrated with a skin layer of resin cotton impregnated with a thermosetting resin via a sound absorbing layer. [Claim 3] A non-breathable layer is sandwiched between two honeycomb plates, and the surface of the honeycomb plate on the inside side of the cabin is integrated with a resin cotton impregnated with a thermosetting resin and a skin layer through a sound absorbing layer. A molded ceiling material characterized in that the other side is made of resin cotton impregnated with a thermosetting resin and integrated with a skin layer.