DEFECT-CONTAINING STRIP AND METHOD FOR DETECTING SUCH DEFECTS

• US 20100162865A1
• Filed: 10/13/2009
• Published: 07/01/2010
• Est. Priority Date: 12/31/2008
• Status: Abandoned Application

• Current Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Original Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Inventors: INNOCENZO, JEFFREY GLENN
• Application Number:
  US12/577,870
• Publication Number:
  US 20100162865A1
• Time in Patent Office: Days
• US Class Current: 83/73
• CPC Class Codes: B26D 1/00 Cutting through work characterised by the nature or movement of the cutting member or particular materials not otherwise provided for; Apparatus or machines therefor; Cutting members therefor
• CPC Class Codes: B26D 5/32 with the record carrier formed by the work itself
• CPC Class Codes: B26D 7/018 Holding the work by suction
• CPC Class Codes: B65H 18/28 Wound package of webs
• CPC Class Codes: B65H 2220/01 indicating an entity as a function of which control, adjustment or change is performed, i.e. input
• CPC Class Codes: B65H 2301/5111 Printing; Marking
• CPC Class Codes: B65H 2511/11 Length
• CPC Class Codes: B65H 2511/512 Marks, e.g. invisible to the human eye; Patterns
• CPC Class Codes: B65H 26/02 responsive to presence of irregularities in running webs
• CPC Class Codes: B65H 35/04 from or with transverse cutters or perforators
• CPC Class Codes: G01N 2021/888 Marking defects
• CPC Class Codes: G01N 21/896 Optical defects in or on transparent materials, e.g. distortion, surface flaws in conveyed flat sheet or rod for other objects G01N21/958
• CPC Class Codes: G02B 5/20 Filters polarising elements G02B5/30
• CPC Class Codes: Y10T 428/24802 Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]
• CPC Class Codes: Y10T 83/145 Including means to monitor product

Abstract

The present invention provides a method for recognizing the presence of at least one defect in a strip of film and identifying its position during film manufacturing; a method for removal of the portion of the film strip containing the defect; and a film strip having at least one defect recognized and its position identified.

Claims

1. A film strip having a longitudinal axis oriented in a winding direction and adapted for cutting into sheets having a length of at least D, comprising:

at least one defect; and

at least one mark on the film strip corresponding to each defect, wherein each mark is positioned at a distance of at least D from the corresponding defect.

2. The film strip according to claim 1, wherein the distance D is greater than or equal to the width of the film strip.

3. The film strip according to claim 1, wherein the film strip comprises a selection from the polymer group consisting of polyethylene, polypropylene, polyester, polycarbonate, polyimide, polyamide, polysulfone, polyethersulfone, cellulose triacetate, cellulose nitrate, and combinations and copolymers thereof.

4. The film strip according to claim 1, wherein at least a portion of the film strip is wound on a roll.

5. The film strip according to claim 1, wherein the film strip comprises a colored transferable layer and an adjacent support layer.

6. A method of marking comprising:

providing a film strip containing at least one defect, the film strip having a longitudinal axis oriented along a winding direction and adapted for cutting into sheets having a length of at least D,

detecting the defect; and

marking a mark on the strip corresponding to the defect, wherein the mark is positioned at a distance of at least D from the defect.

7. The method according to claim 6, wherein the mark is positioned downstream in the winding direction from the defect.

8. The method according to claim 6, wherein the mark is positioned upstream in the winding direction from the defect.

9. A method of removing a defect-containing portion of a film strip comprising:

providing a film strip having a defect and a corresponding mark and having a longitudinal axis oriented along a winding direction and adapted for cutting into sheets having a length of at least D, wherein the corresponding mark is positioned at a distance of at least D from the defect;

moving a portion of the film strip containing the corresponding mark past a means for reading marks on the film strip corresponding to each defect,

reading the corresponding mark,

moving a second portion of the film strip between the defect and the corresponding mark past a means for cutting, first cutting the film strip,

moving a third portion of film strip past the means for reading marks, and

second cutting the film strip when the means for reading the mark reads no additional marks for a distance of at least D, thereby removing the defect-containing portion from the film strip.