Coextruded packaging film

Stock material or miscellaneous articles – Composite – Of addition polymer from unsaturated monomers

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C428S523000

Reexamination Certificate

active

06406797

ABSTRACT:

BACKGROUND OF THE INVENTION
The present invention relates to polymeric film, and more particularly to coextruded packaging film.
SUMMARY OF THE INVENTION
In one aspect of the invention, a packaging film comprises an outer layer comprising a material selected from fully hydrolyzed polyvinyl alcohol, partially hydrolyzed polyvinyl alcohol, and polyethylene oxide; an intermediate layer comprising a material selected from fully hydrolyzed polyvinyl alcohol, partially hydrolyzed polyvinyl alcohol, and polyethylene oxide; and an inner layer comprising a material selected from acid/acrylate copolymer, styrene maleic anhydride copolymer, ethylene acrylic acid copolymer, ionomer, cellulose, hydroxy propyl cellulose, polyether block amide copolymer, polyhydroxy butyric acid, polyhydroxy valeric acid, polyethylene oxide, polyester, copolyester, polyethyloxazoline, polyurethane, partially metal salt neutralized acid/acrylate copolymer, and a blend of acid/acrylate copolymer and ionomer.
In another aspect of the invention, a method for coextruding a packaging film comprises the steps of simultaneously extruding an outer layer comprising a material selected from fully hydrolyzed polyvinyl alcohol, partially hydrolyzed polyvinyl alcohol, and polyethylene oxide, an intermediate layer comprising a material selected from fully hydrolyzed polyvinyl alcohol, partially hydrolyzed polyvinyl alcohol, and polyethylene oxide, and an inner layer comprising a material selected from acid/acrylate copolymer, styrene maleic anhydride copolymer, ethylene acrylic acid copolymer, ionomer, cellulose, hydroxy propyl cellulose, polyether block amide copolymer, polyhydroxy butyric acid, polyhydroxy valeric acid, polyethylene oxide, polyester, copolyester, polyethyloxazoline, polyurethane, partially metal salt neutralized acid/acrylate copolymer, and a blend of acid/acrylate copolymer and ionomer; joining the layers together at an annular coextrusion die; and hot blowing the coextrudate to make the packaging film.
In an alternative method, the materials just described are simutaneously extruded; joined together at a sheet coextrusion die; and cast to make the packaging film.


REFERENCES:
patent: 2155999 (1939-04-01), Procter et al.
patent: 3546716 (1970-12-01), Laumann
patent: 3661695 (1972-05-01), Berliner
patent: 3790067 (1974-02-01), Scheier
patent: 3892905 (1975-07-01), Albert
patent: 4288497 (1981-09-01), Tanaka et al.
patent: 4372311 (1983-02-01), Potts
patent: 4551369 (1985-11-01), Belz
patent: 4612355 (1986-09-01), Belz
patent: 4620999 (1986-11-01), Holmes
patent: 4672956 (1987-06-01), Potter et al.
patent: 4762738 (1988-08-01), Keyes et al.
patent: 4772663 (1988-09-01), Marten et al.
patent: 4828744 (1989-05-01), Kaufmann et al.
patent: 4851472 (1989-07-01), Famili et al.
patent: 4870148 (1989-09-01), Belz et al.
patent: 4930942 (1990-06-01), Keyes et al.
patent: 4948857 (1990-08-01), Marten et al.
patent: 4973416 (1990-11-01), Kennedy
patent: 4990146 (1991-02-01), Deibig et al.
patent: 5108807 (1992-04-01), Tucker
patent: 0010171 (1979-09-01), None
patent: 0142950 (1985-05-01), None
patent: 0226439 (1987-06-01), None
patent: 337568 (1989-10-01), None
patent: 407301 (1991-01-01), None
patent: 457600 (1991-11-01), None
patent: 513692 (1992-11-01), None
patent: 1384791 (1973-02-01), None
patent: 6206644 (1987-03-01), None
patent: 02060906 (1990-03-01), None
patent: 02108534 (1990-04-01), None
patent: 02155999 (1990-06-01), None
patent: 02163149 (1990-06-01), None
patent: WO 92/01037 (1992-01-01), None
US Novel Thermoplastic Air Products 1988.
US Vinol Air Products 1985.
US We Develop Plastics . . . Belland Jun. 1989.
US Vinol Polyvinyl Alcohols Air Products 1980.
US Vinex Thermoplastics . . . Air Products 1980.
US Polyox Water-Soluble . . . Union Carbide 1967.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Coextruded packaging film does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Coextruded packaging film, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Coextruded packaging film will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2960517

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.