Process for developing porosity in air impervious film and articles produced by the process

• US 4,547,920 A
• Filed: 10/19/1983
• Issued: 10/22/1985
• Est. Priority Date: 10/19/1983
• Status: Expired due to Fees

• Current Assignee: Sears Manufacturing Co.
• Original Assignee: Sears Manufacturing Co.
• Inventors: Hinkhouse, Lysle R., Hulsebusch, William H.
• Primary Examiner(s): Anderson, Philip
• Application Number:
  US06/543,500
• Time in Patent Office: 734 Days
• Field of Search: 264/46.8, 264/156, 264/101, 5/481, 5/468, 297/455, 297/456, 297/DIG. 1
• US Class Current: 297/256
• CPC Class Codes: B26F 1/26 Perforating by non-mechanical means, e.g. by fluid jet
• CPC Class Codes: B29L 2031/751 Mattresses, cushions upholstery B29L2031/58
• CPC Class Codes: Y10S 297/01 Foam

Abstract

A process for developing porosity in air impervious film. The process is disclosed for fabricating a cushion article having a cover provided with increased air flow capabilities. A covering is provided for a cushion body, the covering including a laminated film and, preferably, an outer fabric layer. The film includes a first layer having a relatively high temperature melting point and a second layer having a relatively low temperature melting point. The first layer includes perforations, and the second layer is continuous and air impervious. The laminated film is heated at a temperature which approaches or is above the melting temperature of the second layer but below the melting temperature of the first layer to melt the second layer at least in areas coincident with the perforations in the first layer to form air flow passages through the film laminate.

Claims

1. A molded seat cushion or the like which has a cover provided with air flow capabilities, comprising:

a foam body molded in the shape of a desired seat cushion; and

a covering for the foam body including an outer fabric layer and an inner laminated film;

the film including a first layer which is air impervious with the exception of perforations therein, and a second air impervious layer having air passages coincident with the perforations of the first layer, the air passages in the second layer having been formed by melting selected portions of the second layer.

2. A process for developing porosity in air impervious film, comprising the steps of:

providing a laminated film having at least two layers, including a first layer having a relatively high temperature melting point and a second layer having a relatively low temperature melting point, the first layer also having perforations therein and at least the second layer being air impervious; and

heating the laminated film a temperature which approaches or is above said low temperature melting point of the second layer but below said high temperature melting point of the first layer to form holes in the second layer at least in areas coincident with said perforations in the first layer to form air flow passages through the film.

3. The process of claim 2, including the step of applying a pressure differential across the laminated film during said heating step.

4. A process for developing porosity in air impervious film, comprising the steps of:

providing a laminated film which includes a first layer having perforations therein and a second layer that is air impervious, the melting point of the second layer being less than the softening point of the first layer; and

heating the laminated film to a temperature which approaches or is above the melting point of the second layer but below the softening point of the first layer to form holes in the second layer at least in areas coincident with said perforations in the first layer to form air flow passages through the film.

5. The process of claim 4, including the step of applying a pressure differential across the laminated film during said heating step.

6. A process for fabricating a cushion article having a cover provided with air flow capabilities, comprising the steps of:

providing a cushion body;

providing a covering for at least part of the cushion body, the covering including a laminated film comprising a first layer having a relatively high temperature melting point and including perforations therein, and a second layer having a relatively low temperature melting point, at least the second layer being air impervious;

placing said covering over the cushion body; and

heating the laminated film to a temperature which approaches or is above said low temperature melting point of the second layer but below said high temperature melting point of the first layer to form holes in the second layer at least in areas coincident with said perforations in the first layer to form air flow passages through the film.

7. The process of claim 6, including the step of applying vacuum to one side of the film during said heating step to aid in forming the holes in said second layer.

8. The process of claim 6 wherein said cover is provided with an outer fabric layer on the outside of said laminated film.

9. The process of claim 6 wherein both said layers of the laminated film are plastic material.

10. A process for fabricating a cushion article having a cover provided with air flow capabilities, comprising the steps of:

providing a mold having the shape of the desired cushion article;

providing a covering for at least part of the cushion article, the covering including a laminated film comprising a first layer having a relatively high temperature melting point, the first layer including perforations therein, and a second layer having a relatively low temperature melting point, at least the second layer being air impervious;

vacuum drawing the covering into the mold;

pouring a settable foaming material into the mold and at least partially curing the foaming material to form a cushion body within said covering; and

heating the covering to a temperature which approaches or is above said low temperature melting point of the second layer but below said high temperature melting point of the first layer to form holes in the second layer at least in areas coincident with said performations in the first layer to form air flow passages through the covering.

11. The process of claim 10 wherein vacuum is applied to one side of the covering during said heating step.

12. The process of claim 10 wherein said covering includes an outer fabric layer on the outside of said laminated film.

13. The process of claim 10 wherein both said layers of the laminated film are plastic material.

15. The process of claim 13 wherein vacuum is applied to one side of the covering during said heating step.

14. A process for fabricating a seat cushion or the like having a cover provided with air flow capabilities, comprising the steps of:

providing a mold having the shape of a desired seat cushion;

providing a covering for the seat cushion, the covering including an outer fabric layer bonded to an inner laminated film, the film including a first layer having a relatively high temperature melting point, the first layer including perforations therein, and a second air impervious layer having a relatively low temperature melting point;

vacuum drawing the covering into the mold;

pouring a settable foaming material into the mold and at least partiallycuring the foaming material to form a cushion body within the covering; and

heating the covering to a temperature which approaches or is above said low temperature melting point of the second layer but below said high temperature melting point of the first layer to form holes in the second layer at least in areas coincident with said perforations in the first layer to form air flow passages through the covering.

16. The process of claim 14 wherein vacuum is applied from a single source for drawing the cover into the mold and for application during said heating step.