JPH10128894A - Foam molding and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stick a soundproof sheet for soundproofing in contact with a vehicle body on a synthetic resin foam without using adhesive. SOLUTION: A soundproof sheet 10 having a large METSUKE amount is set to a predetermined position of a mold 9. Heated and foamed synthetic resin foam 5 is introduced between molds 8 and 9 in the state that the foam 5 is maintained at a heating temperature. The molds 8, 9 are temperature-regulated at 20 to 50 deg.C, and pressed. The resin of the foam 5 at high temperature is impregnated with backing material 6 having small METSUKE amount to reach the sheet 10, and hence the sheet 10 is integrated with the foam 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foam molded article such as a trim which is formed by foaming and pressing like a molded ceiling and which is attached so as to be in direct contact with a vehicle body, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In general, a foam molded body such as a molded ceiling is made of foamed polypropylene or the like, is press-molded into a shape along a vehicle body, and is attached to the vehicle body. In this molded ceiling, it is necessary to prevent hitting noise and rubbing noise from being generated from a portion in contact with the vehicle body, and therefore, a soundproof sheet is attached to a portion in contact with the vehicle body.

FIG. 4 shows a structure of a conventional molded ceiling, which is made of a polypropylene foam or the like and is formed by pressing a synthetic resin foam into a predetermined shape. And a decorative skin 2 made of a nonwoven fabric or the like. A similar technique is disclosed in Japanese Patent Laid-Open No. 4-1.
No. 85328.

Reference numeral 3 denotes a soundproof sheet attached to a portion of the molded ceiling that comes into contact with the vehicle body. Soundproof sheet 3
For example, a nonwoven fabric of a synthetic resin is used. After press-molding the synthetic resin foam 1, the soundproof sheet 3 is provided at a predetermined position of the synthetic resin foam 1 with a bonding agent 4 such as an adhesive or an adhesive.
Are bonded together.

[0005]

A conventional foam molded article such as a molded ceiling is manufactured by forming a foamed synthetic resin foam 1 by a press and then attaching a soundproof sheet 3 with an adhesive or the like. The process is complicated, complicated, and time-consuming.

A bonding agent 4 such as an adhesive or a pressure-sensitive adhesive is separately provided.
It is necessary and has a problem of increasing material costs.

[0007] Further, after bonding, the soundproof sheet 3
Was easily peeled off, and the soundproofing effect was reduced due to the peeling.

The present invention has been made in view of such a conventional problem, and allows a soundproof sheet to be integrally attached to a synthetic resin foam without performing bonding using a bonding agent. Accordingly, it is an object of the present invention to provide a foam molded article which can simplify the manufacturing process, can be manufactured at low cost, and does not peel off the soundproof sheet.

Another object of the present invention is to provide a production method capable of favorably producing the foam molded article.

[0010]

In order to achieve the above object, a foamed molded article according to claim 1 comprises a heat-foamed synthetic resin foam and a soundproofing sheet having a large basis weight comprising a backing material having a small basis weight. Characterized by being integrated via

Since the synthetic resin foam can easily penetrate the backing material having a small basis weight to reach the soundproof sheet having a large basis weight, the soundproof sheet is formed of a synthetic resin foam so as to be attached to the synthetic resin foam. Integrated with the body.
In this integrated state, the bonding strength between the synthetic resin foam and the soundproof sheet is strong, and the soundproof sheet does not peel off.

The backing material is for preventing draw down of the synthetic resin foam at the time of heating and foaming, and it is preferable that the backing material is as thin as possible in order to improve heat conduction at the time of heating. It is.

According to a second aspect of the present invention, there is provided the foam molded article according to the first aspect, wherein the synthetic resin foam is formed into a predetermined shape by a cold press, and the soundproof sheet is formed of a cold-formed synthetic resin foam. It is characterized in that it is integrated with the synthetic resin foam at the time of pressing.

Although the synthetic resin foam is formed into a predetermined shape by the cold pressing, a part of the synthetic resin of the synthetic resin foam penetrates the backing material during the cold pressing.
Integrated with soundproof sheet. Therefore, there is no need to bond the soundproof sheet to the synthetic resin foam using a bonding agent such as an adhesive.

According to a third aspect of the present invention, there is provided the foam molded article according to the first or second aspect, wherein the soundproof sheet is attached to an automobile so as to come into contact with a vehicle body.

Since the soundproof sheet comes into contact with the vehicle body,
Rubbing noise does not occur.

In a fourth aspect of the present invention, there is provided a synthetic resin which is obtained by setting a soundproof sheet having a large basis weight at a predetermined position of a press die, bonding a backing material having a small basis weight, and heating and foaming the synthetic resin. The foam is introduced between press dies so that the heating temperature is maintained, and the backing material faces the soundproof sheet, and is formed into a predetermined shape in which the soundproof sheet is integrated by cold pressing of the press mold. It is characterized by doing.

The synthetic resin foam is formed into a predetermined shape by performing cold pressing. In this cold press,
The high-temperature synthetic resin foam penetrates the backing material and reaches the soundproof sheet set in the press die, so that the soundproof sheet is integrated with the synthetic resin foam via the backing material.

According to a fifth aspect of the present invention, there is provided the method for producing a foamed molded article according to the fourth aspect, wherein the temperature of the heat foaming is about 22.
0-240 ° C, and the temperature of the cold press is about 20-50
° C.

The temperature of 220 to 240 ° C. is the temperature at which the foaming agent completes foaming. By heating to this temperature, reliable foaming can be performed. By cold pressing at 20-50 ° C,
The synthetic resin foam and the soundproof sheet are integrated.

[0021]

According to the first aspect of the present invention, since the synthetic resin foam penetrates into the backing material having a small basis weight to reach the soundproof sheet having a large basis weight, the soundproof sheet is integrated with the synthetic resin foam. I do. Therefore, bonding using a bonding agent becomes unnecessary, and the process can be simplified. In this integrated state, the bonding strength between the synthetic resin foam and the soundproof sheet is strong,
The soundproof sheet does not peel off.

According to the second aspect of the present invention, in addition to the effect of the first aspect, the synthetic resin foam is formed into a predetermined shape by cold pressing, and one of the synthetic resin foams is formed at the time of cold pressing. There is an effect that the synthetic resin of the portion permeates the backing material and is integrated with the soundproof sheet.

According to the invention of claim 3, claim 1 or 2
In addition to the effects described above, the soundproof sheet comes into contact with the vehicle body, so that there is an effect that hitting noise and rubbing noise do not occur.

According to the invention of the method of manufacturing a foamed molded article according to the fourth aspect, in a cold press for molding a synthetic resin foam into a predetermined shape, the high-temperature synthetic resin foam penetrates the backing material and is pressed into a press die. In order to reach the set soundproof sheet, the soundproof sheet is integrated with the synthetic resin foam via the backing material.

According to the invention of claim 5, 220 to 240
By heating to a temperature of ° C, reliable foaming can be performed, and the synthetic resin foam and the soundproof sheet are integrated by cold pressing at 20 to 50 ° C.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a process diagram of an embodiment of the production method of the present invention, which comprises a heating foaming step and a cold pressing step.

Reference numeral 5 denotes a synthetic resin foam, on the lower surface of which a backing material 6 is adhered. The synthetic resin foam 5 can be obtained by heating and foaming a foamable synthetic resin base material formed into a plate by mixing a synthetic resin foaming agent. As the synthetic resin, a polyolefin resin such as polypropylene, polyethylene, or a copolymer thereof, a polyurethane resin, or the like can be used. In particular, polypropylene is preferable.

The foaming agent is a compound which is decomposed by heating to generate a gas, and one or more of azodicarbonamide, barium azodicarboxylate, dinitrosopentahexanetetramine, dinitrosopentamethylenetetramine and the like are selected. can do. The compounding ratio of the foaming agent is 1 to 20 parts by weight with respect to 100 parts by weight of the synthetic resin.
Particularly, 2 to 5 parts by weight is preferable.

The backing material 6 is attached to a foamable synthetic resin base material before foaming. Backing material 6
Is to prevent drawdown of the synthetic resin due to softening during heating and foaming, and a nonwoven fabric of a synthetic resin such as polyester and nylon is used.

As the backing material 6, a material having a small basis weight is used. This is because the drawdown of the synthetic resin can be prevented even if the weight per unit area is small. In addition to this, at the time of cold pressing to be described later, good penetration of the synthetic resin is promoted and the soundproof sheet 10 and the synthetic resin are integrated. This is to ensure the conversion. As the basis weight of the backing material 6, for example,
It can be appropriately selected in the range of about 30 to 50 g / m ² .

In the heating and foaming step, a heater 7 is used. As the heater 7, a thermocouple heater, an infrared heater, and other heaters can be used. Heating by the heater 7 is performed up to about 220 to 240 ° C., which is the foaming agent foaming completion temperature, and foaming is performed with this heating. Become.

Further, by heating and foaming, the resin of the synthetic resin foam 5 penetrates well into the backing material 6 having a small basis weight,
The backing material 6 is in a state of relatively entering the resin.

In the cold pressing step, a press molding machine is used. The press molding machine has a pair of press dies 8 and 9 opposed to each other, and one press dies 8 moves so as to clamp and open the other press dies 9.

Prior to the cold press, the soundproof sheet 10 is set in the press die 9. The soundproof sheet 10 is set at a portion corresponding to a contact portion with the vehicle body. In the illustrated example, the soundproof sheet 10 is placed and set on the shoulder portion of the other press die 9.

As the soundproof sheet 10, a sheet having a larger basis weight than the backing material 6 is used. This is because a material having a large basis weight can attenuate or absorb sound and is suitable as a soundproofing material. In this embodiment, about 1
The soundproof sheet 10 having a basis weight of 00 to 200 g / m ² is used.

Before pressing, press dies 8, 9
Is adjusted to a temperature range of about 20 to 50 ° C., and cold pressing is performed by pressing in this temperature range.

Heat-foamed plate-like synthetic resin foam 5
Is introduced between the press dies 8, 9 which are opened, and press-formed. In this case, the synthetic resin foam 5 is introduced between the press dies 8 and 9 so that the backing material 6 faces the soundproof sheet 10. Also, synthetic resin foam 5
Is the heated foaming temperature, i.e., about 220-240C
Is held between the press dies 8 and 9 while maintaining the pressure.

Reference numeral 11 denotes a skin made of a non-woven fabric such as a polyester such as polyethylene terephthalate or a polyolefin such as polypropylene, and press dies 8 and 9 facing the surface of the synthetic resin foam 5 opposite to the backing material 6.
Will be introduced during

In the above state, the press die 8 descends to perform mold clamping, and presses to perform cold pressing.

The cold pressing is performed by applying pressure for about 40 to 60 seconds. In this cold pressing, the high-temperature synthetic resin of the synthetic resin foam penetrates the backing material 6 and further penetrates the soundproof sheet 10. Thereby, the soundproof sheet 1
Numeral 0 is integrated with the synthetic resin foam 5 via the backing material 6 and attached to the synthetic resin foam 5. At the same time, the synthetic resin foam 5 is pressed into a predetermined shape, and the skin 11 is attached to the synthetic resin foam 5 to form the foam molded body 12 shown in FIG.

In FIG. 2, a soundproof sheet 10 is attached to the lower surface of the synthetic resin foam 5 via a backing material 6, and a skin 11 is attached to the upper surface of the synthetic resin foam 5.

In such an embodiment, the foam molding 12
Since the soundproof sheet 10 can be attached simultaneously with the cold pressing of the soundproof sheet 1, the soundproof sheet 1
There is no need to attach 0. For this reason, the step of attaching the soundproof sheet 10 is not required, and the step can be simplified, and an adhesive or a pressure-sensitive adhesive is not required, so that the soundproof sheet 10 can be manufactured at low cost. In addition, since the soundproof sheet 10 is firmly attached, the soundproof sheet 10 does not peel off carelessly, and soundproofing can be reliably performed.

FIG. 3 shows a state in which the molded foam molded body 12 is used as a molded ceiling of an automobile, 13 is a roof panel, 14 is an inner rail, 15 is a windshield panel, and 16 is a body side welt. An end of the foam molded body 12 as a molded ceiling is fixed to the body side welt 16, and is arranged so as to contact the inner rail 14 in this fixed state.

In this case, the foam molding 12 has the outer skin 11 located on the indoor side, and the soundproof sheet 10 attached to the inner rail 14. Since the soundproof sheet 10 has a large weight per unit area, it can satisfactorily attenuate striking noise and rubbing noise caused by contact with the inner rail 14.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a manufacturing process according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the manufactured foam molded article.

FIG. 3 is a cross-sectional view showing a state of attachment to an automobile.

FIG. 4 is a cross-sectional view of a conventional foam molded article.

[Explanation of symbols]

 5 Synthetic resin foam 6 Backing material 7 Heater 8, 9 Press mold 10 Soundproof sheet 11 Skin

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI B29L 31:58

Claims (5)

[Claims] 1. A foamed molded article characterized in that a heat-foamed synthetic resin foam and a soundproof sheet having a large basis weight are integrated via a backing material having a small basis weight. 2. The foam molded article according to claim 1, wherein the synthetic resin foam is formed into a predetermined shape by a cold press, and the soundproof sheet is formed by a cold press of the synthetic resin foam. A foam molded article characterized by being integrated with a synthetic resin foam. 3. The foam molded article according to claim 1, wherein the soundproof sheet is attached to an automobile such that the soundproof sheet contacts a vehicle body. 4. A soundproof sheet having a large basis weight is set at a predetermined position of a press die, and a backing material having a small basis weight is bonded and heated and foamed, while maintaining the heating temperature. And a backing material is introduced between the press dies so as to face the soundproof sheet, and the soundproof sheet is formed into a predetermined shape by cold pressing of the press mold. . 5. The method for producing a foamed molded article according to claim 4, wherein the temperature of the hot foaming is about 220 to 240 ° C., and the temperature of the cold press is about 20 to 50 ° C. A method for producing a foamed molded article.