Apparatus for the rapid continuous corona poling of polymeric films

Claim 2

Apparatus for continuously enhancing piezoelectric properties of polymeric film exhibiting such properties comprising a rotating drum contacting said film for transport thereof along a defined path, a corona discharge electrode roller mounted for movement along circumference of said drum in an oscillating motion normal to axis of rotation of said rotating drum, said film having at least one area in constant contact with said rotating drum and oscillating electrode, and means for providing continuous corona discharge from said electrode through said film substantially at said contact area for poling said film.

Claim 3

The apparatus of claim 1 further characterized by a heating chamber disposed downstream of said electrode roller, and other means for urging said poled film through said heating chamber.

Claim 4

The apparatus of claim 2 wherein said electrode roller is provided with a textured surface.

Claim 5

The apparatus of claim 2 wherein said electrode roller is provided with a knurled surface.

Claim 6

The apparatus of claim 2 wherein said electrode roller is provided with a grooved surface.

Claim 7

The apparatus of claim 3 wherein said oscillating motion of said electrode is characterized by a rolling thereof over said film.

Claim 8

The apparatus of claim 6 wherein said rotating drum contacts said film for transport thereof over a portion of circumference of said drum.

Claim 9

The apparatus of claim 7 wherein said film is provided with an electroconductive coating on one or both sides thereof.

Claim 10

The apparatus of claim 7 further characterized by a co-film disposed between said electrode roller and polymeric film in direct contact therewith and, means for transporting said co-film with said polymeric film at substantially identical speeds.

Claim 11

The apparatus of claim 9 wherein said polymeric film comprises polyvinylidene fluoride.

Claim 12

The apparatus of claim 9 wherein said co-film comprises co-polymerized vinylidene fluoride and tetrafluoroethylene in a ratio of about 70-30 weight percent respectively.

Claim 15

The apparatus of claim 12 wherein said electrode means is provided with a surface which is textured, knurled or grooved.

Claim 16

The apparatus of claim 13 wherein a co-film is disposed between said electrode means and said polymeric film and in direct contact therewith, and means for transporting said co-film with said polymeric film at substantially identical speeds.

Claim 17

The apparatus of claim 14 further characterized by a heating chamber downstream of said electrode means, and motorized means for urging said poled film through said heating chamber.

Claim 18

The apparatus of claim 14 further characterized by said polymeric film being devoid of metallic coatings on either surface thereof.

Claim 19

The apparatus of claim 14 wherein said poled film subsequent to treatment in said heating chamber possesses pyroelectric properties.

Claim 20

The apparatus of claim 14 wherein means are provided for controlling the speed of rotation of said drum and frequency of oscillations of said electrode means.

Claim 21

The apparatus of claim 14 further characterized by the axis of rotation of said drum and oscillating movement of said electrode means being substantially coincident.

Claim 22

The apparatus of claim 15 wherein heating means are disposed adjacent said rotating drum and electrode means to provide external heat thereto.

Claim 23

Apparatus for continuously enhancing piezoelectric properties of polymeric film exhibiting such properties comprising a rotating drum contacting said film for transport thereof along a defined path, a corona discharge electrode roller mounted for movement along circumference of said drum in an oscillating motion, and means for providing continuous corona discharge from said electrode through said film for poling said film.

Claim 24

Apparatus for continuously enhancing piezoelectric properties of polymeric film exhibiting such properties comprising a rotating drum contacting said film for transport thereof along a defined path, a corona discharge electrode roller mounted for movement along circumference of said drum in an oscillating motion, and means for providing continuous corona discharge from said electrode through said film for poling said film.

Claim 25

Apparatus for continuously enhancing piezoelectric properties of polymeric film exhibiting such properties comprising a rotating drum contacting said film for transport thereof along a defined path, a corona discharge electrode roller having a textured surface mounted for movement along circumference of said drum in an oscillating motion, means for spacing said textured surface from said film, and other means for providing continuous corona discharge from said textured surface through said film for poling said film.

Claim 26

Apparatus for continuously enhancing piezoelectric properties of polymeric film exhibiting such properties comprising a rotating drum contacting said film for transport thereof along a defined path, a corona discharge electrode roller having a textured surface mounted for movement along circumference of said drum in an oscillating motion, means for spacing said textured surface from said film, and other means for providing continuous corona discharge from said textured surface through said film for poling said film.

Claim 27

The apparatus of claim 22 wherein said means comprises a dielectric rim provided at each end of said electrode roller, and said film has at least one area in constant contact with said rotating drum.

Claim 28

The apparatus of claim 23 further characterized by a heating chamber disposed downstream of said electrode roller, and additional means for urging said poled film through said heating chamber.

Claim 29

The apparatus of claim 23 wherein said textured surface of said electrode roller is a knurled surface.

Claim 30

The apparatus of claim 23 wherein said textured surface of said electrode is a grooved surface.

Claim 31

The apparatus of claim 23 wherein said oscillating motion of said electrode is characterized by a rolling thereof over said film.

Claim 32

The apparatus of claim 23 wherein said rotating drum contacts said film for transport thereof over a portion of circumference of said drum.

Claim 33

The apparatus of claim 28 wherein said film is provided with an electroconductive coating on one or both sides thereof.

Claim 34

The apparatus of claim 28 further characterized by a co-film disposed between said electrode roller and polymeric film in direct contact therewith and, means for transporting said co-film with said polymeric film at substantially identical speeds.

Claim 35

The apparatus of claim 30 wherein said polymeric film comprises polyvinylidene fluoride.

Claim 36

The apparatus of claim 30 wherein said co-film comprises co-polymerized vinylidene fluoride and tetrafluoroethylene in a ratio of about 70-30 weight percent respectively.

Claim 37

Apparatus for continuously enhancing piezoelectric properties of polymeric film exhibiting such properties comprising a rotating drum having a portion of its circumferential surface touching said film for continuously transporting and guiding said film along a defined path, a corona discharge electrode roller having a dielectric rim provided at each end thereof and a textured surface on said electrode therebetween, said electrode oscillating on said film by means of said rims being in direct contact with said film and said textured surface being spaced therefrom, said oscillations being characterized by a rolling movement between two spaced lines parallel with axis of rotation of said drum on said circumferential surface such that given lines parallel with and between said spaced lines are swept a multiplicity of passes by said oscillating electrode roller prior to said given lines being transported downstream of said two spaced lines, and means for providing continuous corona discharges from said textured surface of said electrode roller through said film for poling thereof.

Claim 38

Apparatus for continuously enhancing piezoelectric properties of polymeric film exhibiting such properties comprising a rotating drum having a portion of its circumferential surface touching said film for continuously transporting and guiding said film along a defined path, a corona discharge electrode roller having a dielectric rim provided at each end thereof and a textured surface on said electrode therebetween, said electrode oscillating on said film by means of said rims being in direct contact with said film and said textured surface being spaced therefrom, said oscillations being characterized by a rolling movement between two spaced lines parallel with axis of rotation of said drum on said circumferential surface such that given lines parallel with and between said spaced lines are swept a multiplicity of passes by said oscillating electrode roller prior to said given lines being transported downstream of said two spaced lines, and means for providing continuous corona discharges from said textured surface of said electrode roller through said film for poling thereof.

Claim 39

The apparatus of claim 33 wherein said textured surface of said electrode roller is a knurled surface.

Claim 40

The apparatus of claim 33 wherein said textured surface of said electrode roller is a grooved surface.

Claim 41

The apparatus of claim 33 wherein a co-film is disposed between said electrode roller and said polymeric film, and means for transporting said co-film with said polymeric film at substantially identical speeds.

Claim 42

The apparatus of claim 36 further characterized by a heating chamber downstream of said electrode roller, and motorized means for urging said poled film through said heating chamber.

Claim 43

The apparatus of claim 36 further characterized by said polymeric film being devoid of metallic coatings on either surface thereof.

Claim 44

The apparatus of claim 36 further characterized by said polymeric film having an electroconductive metallic coating on one or both sides thereof.

Claim 45

The apparatus of claim 36 wherein said poled film subsequent to treatment in said heating chamber possesses pyroelectric properties.

Claim 46

The apparatus of claim 36 wherein means are provided for controlling the speed of rotation of said drum and frequency of oscillations of said electrode roller.

Claim 47

The apparatus of claim 36 further characterized by the axis of rotation of said drum and oscillating movement of said electrode roller being substantially coincident.