초록 ▼

A method for manufacturing a novel air permeable composite film is disclosed. The air permeable composite film has a polymer layer with a top face and a bottom face and a sealing layer covering the top face. The polymer layer is first perforated by virtue of an impression process to form a plurality

A method for manufacturing a novel air permeable composite film is disclosed. The air permeable composite film has a polymer layer with a top face and a bottom face and a sealing layer covering the top face. The polymer layer is first perforated by virtue of an impression process to form a plurality of tiny gaps in it for air permeation. Then the sealing layer is coated on the top face of the polymer layer to fill the gaps. The differential pressure between the top face and bottom face of the polymer layer enlarges the gaps and makes the gaps become air permeable.

대표청구항 ▼

What is claimed is: 1. A method of manufacturing an air permeable packaging bag, the method comprising the steps of: providing a first polymer film and a second polymer film, at least the first polymer film having a plurality of gaps extending through the first polymer film and being formed therein

What is claimed is: 1. A method of manufacturing an air permeable packaging bag, the method comprising the steps of: providing a first polymer film and a second polymer film, at least the first polymer film having a plurality of gaps extending through the first polymer film and being formed therein by virtue of an impression process, the gaps being configured to restrict air permeation through the first polymer film in a static state; overlapping the first and second polymer films; and performing a sealing process to seal the overlapping edges of the first and second polymer films to define an open interior and an opening for the air permeable packaging bag, wherein when the air pressure within the open interior of the packaging bag is greater than the air pressure outside of the open interior, the plurality of gaps gradually deform and open to permit the air within the open interior of the packaging bag to permeate through the first polymer film, the plurality of gaps being configured to return to the static state to restrict air permeation through the first polymer film when the air pressure outside of the packaging bag is substantially equal to or greater than the air pressure within the open interior such that the packaging bag can be reused to regulate another increase of pressure within the open interior of the packaging bag. 2. The method of claim 1 wherein the method further comprises a step of applying sealing material on a first surface of the first polymer film. 3. The method of claim 2 wherein the sealing material is applied after the impression process, and the sealing material applied on the first polymer film fills the gaps of the first polymer film to restrict air permeation in the static state, wherein upon the application of heat, the sealing material softens and permits the opening of the gaps in the first polymer film to allow air permeation through the first polymer film. 4. The method of claim 2 wherein the sealing material is applied before the impression process, and the method further comprises a thermal process to soften the sealing material after the impression process, so that the sealing material can fill the gaps in the first polymer film to prevent air permeation. 5. The method of claim 2 further comprising a second coating process to apply a second sealing material on a second surface of the first polymer film. 6. The method of claim 1 wherein the first and second polymer films comprise one or more layers each made by one of the following materials: acrylic resins, polyester, polyethylene (PE), polypropylene (PP), copolymer of PE and PP, ethylene-styrene copolymer (ES), cyclo olefin, polyethylene terephthalate (PET), polyvinyl alcohol (PVA), ethylene-vinyl acetate (EVA), ethylene/methacrylic acid (E/MAA) ionomer, polyethylene naphthalate (PEN), poly ether ether ketone (PEEK), polycarbonate (PC), polysulfone, polyimide (PI), polyacrylonitrile (PAN), styrene acrylonitrile (SAN), polyurethane (PU), synthetic papers, gassine papers, or polyolefin coated paper. 7. The method of claim 1 wherein at least two overlapping edges are sealed in the sealing process so as to form the opening in the air permeable packaging bag. 8. The method of claim 1 wherein at least one curving edge is sealed in the sealing process as to form the opening in the air permeable packaging bag. 9. The method of claim 1 wherein the sealing process is performed using a heat activating process, an ultrasonic pressing process, or an adhesive. 10. The method of claim 1 wherein the method further includes a step of closing the opening of the air permeable packaging bag by using a zipper, a ziploc, a sliding zipper, a heat activating process, an ultrasonic pressing process, or an adhesive.