DASHBOARD INSULATOR FOR MOTOR VEHICLES AND MANUFACTURING METHOD THEREFOR

• US 20110221223A1
• Filed: 09/25/2009
• Published: 09/15/2011
• Est. Priority Date: 09/26/2008
• Status: Active Grant

• Current Assignee: Howa Co., Ltd. (Rengo Company Limited)
• Original Assignee: Howa Textile Industry Co., Ltd.
• Inventors: Mizata, Shuichi
• Granted Patent: US 8,371,635 B2
• Time in Patent Office: Days
• US Class Current: 296/39.3
• CPC Class Codes: B60R 13/083 for fire walls or floors
• CPC Class Codes: G10K 11/168 Plural layers of different materials, e.g. sandwiches

Abstract

In a dashboard insulator for a vehicle, an inner layer laminated between front and rear layers is formed by laminating fusion, barrier and other fusion films and has a large number of small holes with a uniform opening rate. The both layers are formed by a thermoplastic material with predetermined basis weight, and Young'"'"'s modulus. The both fusion films formed by a thermoplastic material with a melting point lower than that of the barrier film fuse the both layers to the barrier film. Each fusion part of the both fusion films has a predetermined fusion force in its predetermined range.

Claims

1. A dashboard insulator for a motor vehicle, comprising:

first and second outer layers formed by a porous material and located opposing to each other; and

at least one inner layer laminated between said first and second outer layers and including a barrier film and first and second fusion films laminated to said barrier film from both faces of said barrier film respectively so that said first and second outer layers are fusioned to the barrier film,

wherein said porous material forming one of said first and second outer layers has a basis weight within a range of 100 (g/m²) to 1,600 (g/m²), and said porous material forming the other of said first and second outer layers has a basis weight within a range of 100 (g/m²) to 1,600 (g/m²) and Young'"'"'s modulus within a range of 50,000 (N/m²) to 300,000 (N/m²);

said inner layer has a thickness within a range of 25(%) to 80(%), said inner layer forming penetratingly thereto a large number of small holes at a uniform opening rate within a range of 0.5(%) to 5(%);

a fusion part by said first fusion film between said first outer layer and said barrier film has a fusion force within a range of 5 (N/5 cm) to 20 (N/5 cm) at its portion equal to or more than 50(%); and

a fusion part by said second fusion film between said second outer layer and said barrier film has a fusion force within a range of 5 (N/5 cm) to 20 (N/5 cm) at its portion equal to or more than 50(%).

2. The dashboard insulator for a motor vehicle according to claim 1, wherein said porous material forming said first and second outer layers is a fibrous structure body material or a porous synthetic resin material;

said barrier film of said inner layer is formed by a thermoplastic resin material;

said first fusion film of said inner layer is formed by a thermoplastic resin material with a melting point lower than that of said thermoplastic resin material forming said barrier film; and

said second fusion film of said inner layer is formed by a thermoplastic resin material with a melting point lower than that of said thermoplastic resin material forming said barrier film.

3. The dashboard insulator for a motor vehicle according to claim 2, wherein said fibrous structure body material forming said first and second outer layers is felt made of polyethyleneterephthalate, cotton or wool;

said thermoplastic resin material forming said barrier film is nylon or polyester;

said thermoplastic resin material forming said first fusion film is polyethylene or polypropylene; and

said thermoplastic resin material forming said second fusion film is polyethylene or polypropylene.

4. A manufacturing method of a dashboard insulator for a motor vehicle, comprising the steps of:

an outer layer forming step for forming one of first and second outer layers by a porous material having a basis weight within a range of 100 (g/m²) to 1,600 (g/m²) and forming the other of said first and second outer layers by a porous material having a basis weight within a range of 100 (g/m²) to 1,600 (g/m²) and Young'"'"'s modulus within a range of 50,000 (N/m²) to 300,000 (N/m²);

an inner layer forming step for forming a first cylindrical film for a barrier film, a second cylindrical film for a first fusion film containing said first cylindrical film and a third cylindrical film for a second fusion film contained by said first cylindrical film respectively by a first thermoplastic resin material in a molten state, a second thermoplastic resin material in a molten state and with a melting point lower than that of the first thermoplastic resin material and a third thermoplastic resin material in a molten state and with a melting point lower than that of the first thermoplastic resin material by using a multi-layer inflation molding machine,

thereafter cooling and bonding said second, first and third cylindrical films to form a single cylindrical film of a thickness within a range of 25 (μ

m) to 80 (μ

m), forming a sheet-like film from said single cylindrical film, and forming a large number of small holes to said sheet-like film at a uniform opening rate within a range of 0.5(%) to 5(%) thereby to form said inner layer constructed by said first fusion film, said barrier film and said second fusion film; and

a fusion step for interposing said inner layer between said first and second outer layers in a laminated state to constitute a three-layered layer body,

and heating said three-layered layer body at a temperature between the melting point of the first thermoplastic material and each melting point of the second and third thermoplastic materials so that said first and second fusion films are melted and pressurized and thereafter are cooled so as to fuse said first and second outer layers to said barrier film from both faces thereof by said first and second fusion films,

wherein for fusing said first and second outer layers to said barrier film from the both faces thereof in said fusion step, said pressurization is performed so that a fusion part by said first fusion film between said first outer layer and said barrier film has a fusion force within a range of 5 (N/5 cm) to 20 (N/5 cm) at its portion equal to or more than 50(%), and a fusion part by said second fusion film between said second outer layer and said barrier film has a fusion force within a range of 5 (N/5 cm) to 20 (N/5 cm) at its portion equal to or more than 50(%).