JPS5931930B2 - Manufacturing method of sound absorption board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a sound absorbing board that is attached to the inner walls of buildings such as factories, tunnels, ceilings and side walls of shelters, inner walls of ducts, etc., and used as soundproof enclosures for machinery, etc. .

Conventionally, for example, Japanese Unexamined Patent Publication No. 49-31118 describes a sound absorbing material in which a protective layer having a large number of through holes is laminated integrally with a fiber mat layer using an adhesive.

However, such sound absorbing materials have the disadvantage that it takes time for the adhesive to harden, resulting in low manufacturing efficiency and relatively high costs. In addition, the adhesive protrudes into the fiber mat layer corresponding to the through holes in the protective layer and covers the fiber mat layer, resulting in a decrease in sound absorption performance and an unsightly appearance. Furthermore, unless the adhesive is applied uniformly, stable adhesive strength cannot be obtained, and the manufacturing process is labor-intensive. In view of these conventional drawbacks, the present inventor has conducted extensive research and has completed a method for manufacturing a sound absorbing plate that eliminates the above-mentioned drawbacks.

The present invention will be described below with reference to the drawings.

In the drawings, reference numeral 1 denotes a perforated plate, which is a plate-like body made of metal such as iron or aluminum, synthetic resin, or the like.

A large number of sound absorbing holes 11, 11, . . . are bored in the perforated plate 1, and the aperture ratio is usually 30 to 60%, but the aperture ratio is not particularly limited. Also, sound absorption hole 1
The shape of 1 may be circular, oval, square, slit, etc. Reference numeral 2 is a nonwoven fabric, which is made of glass fiber or the like and has a thickness of 1 to 5 W.

In addition, the nonwoven fabric 2 has denser fiber spacing than conventional glass wool, rock wool, etc., and has the same level of sound absorption performance even if it is thin, and is superior to conventional fabrics in terms of strength and water resistance. used. Reference numeral 3 is a hot melt type resin film having adhesive properties, which is usually made from a modified polyolefin resin, and is sandwiched between the perforated plate 1 and the nonwoven fabric 2, as will be described later, to bond the two together. It is for the purpose of

Furthermore, if the thickness of the resin film 3 is less than 15 μm, the adhesive strength will be poor, and if it is more than 30 μm, the sound absorption holes 1 of the perforated plate 1 will be damaged as described below.
The thickness of the nonwoven fabric 2 is preferably 15 to 30 μm because the portion corresponding to 1 does not shrink and break to open, thereby reducing the sound absorption performance of the nonwoven fabric 2. Next, to explain the manufacturing method of the present invention, a resin film 3 is formed on the surface of the nonwoven fabric 2.
and perforated plates 1 are laminated one after another, and 1 is pressed by a hot press machine 4.
The resin film 3 may be melted by heating and pressurizing at a temperature of 80 to 220° C. for 30 seconds to 2 minutes, and the perforated plate 1 and the nonwoven fabric 2 may be integrated by pressure bonding through the resin film 3.

At this time, the resin film 3 corresponding to the sound-absorbing holes 11 of the perforated plate 1 momentarily contracts, breaks, and opens, and the nonwoven fabric 2 is exposed in the sound-absorbing holes 11. Further, it is preferable to coat the end and back surfaces of the nonwoven fabric 2 with a silicone resin coating film, since a sound absorbing plate with good water resistance can be obtained. Next, examples of the present invention will be described. Thickness 371IRs Density 132! /M8
A modified polyethylene film with a thickness of 20 μm was laminated on the surface of a nonwoven fabric, and a number of sound absorption holes with a diameter of 371 gt were bored on the surface of the film, and the aperture ratio was 38%. 20 iron plates are laminated and pressed using a hot press machine.
The iron plate and non-woven fabric are firmly bonded and integrated by heating and pressurizing at a temperature of 0°C for 30 seconds, and the adhesive resin film corresponding to the sound-absorbing holes in the perforated plate contracts and ruptures, resulting in good sound-absorbing performance. We obtained a sound absorbing board.

Incidentally, Table 1 shows the sound absorption coefficient of the above-mentioned sound absorption board, which was measured by a normal incidence sound absorption coefficient measuring method with a hollow layer of 5071i11 provided behind the sound absorption board. As detailed above,
In the manufacturing method of the present invention, an adhesive resin film and a perforated plate are successively laminated on the surface of a non-woven fabric, and the perforated plate and non-woven fabric are bonded and integrated through the resin film by heating and pressing. It is possible to improve manufacturing efficiency without requiring time for manufacturing, and the manufacturing work does not require much time and effort.

In addition, the perforated plate and the nonwoven fabric can be uniformly bonded and integrated, and the adhesive does not protrude and spoil the aesthetic appearance as in the past. Furthermore, since the adhesive resin film corresponding to the sound absorption holes of the perforated plate is shrunk and broken to open the openings, the nonwoven fabric in the sound absorption holes is directly exposed to the outside, so that the sound absorption performance is not impaired, and the openings are made of nonwoven fabric. , the adhesive resin film and the perforated plate can be integrated by heat and pressure at the same time, so the manufacturing process does not become complicated.

[Brief explanation of the drawing]

Fig. 1 is a side view showing one embodiment of the manufacturing method of the present invention;
The figure is a perspective view showing one embodiment of a sound absorbing plate manufactured by the manufacturing method of the present invention. 1...Perforated plate, 11...Sound absorption hole, 2.
...Nonwoven fabric, 3...Adhesive resin film, 4...Hot press machine.

Claims (1)

[Claims] 1. On the surface of a thin nonwoven fabric with dense fiber spacing,
An adhesive resin film with a thickness of 15 to 30 μm and a perforated plate with a large number of sound absorption holes are laminated one after another and heated to 180 to 220°C.
The method is characterized in that the perforated plate and the non-woven fabric are integrated by heating and pressurized at a temperature of A method of manufacturing a sound absorbing board.