Method and apparatus for manufacturing synthetic resin tubular film having occludent means in the inside surface thereof

Claim 1

A method of manufacturing a tube to be used for forming synthetic resin bags provided with occludent means comprising, (a) a step wherein is molded continuously by passing through a mold plastic forming a tubular bag body and integrally therewith in the inside of said bag body in pairs male and female ribs for occludent use, next, (b) a step wherein air is delivered into said tubular body and said body is kept under uniform pressure, (c) tension is imparted to the tubular film between said mold and delivery rolls provided as clasping means of said tubular body, (d) cold air is delivered from a zone surrounding said tubular body during its travel to cool the film directly from the outside, and further (e) a step wherein the male and female ribs are occluded while said tubular bag body is being pressed flat.

Claim 2

A method of manufacturing a tube to be used for forming synthetic resin bags provided with occludent means comprising, (a) a step wherein is molded continuously by passing through a mold plastic forming a tubular bag body and integrally therewith in the inside of said bag body in pairs male and female ribs for occludent use, next, (b) a step wherein air is delivered into said tubular body and said body is kept under uniform pressure, (c) tension is imparted to the tubular film between said mold and delivery rolls provided as clasping means of said tubular body, (d) cold air is delivered from a zone surrounding said tubular body during its travel to cool the film directly from the outside, and further (e) a step wherein the male and female ribs are occluded while said tubular bag body is being pressed flat.

Claim 3

The method of forming a continuous plastic tube with circumferentially spaced axially extending complementary interlocking profiles formed integrally therewith by extruding the tube through a die having an annular opening and profiles projecting therefrom comprising, (a) delivering a main flow stream of plastic to the annular opening in the die forming a tube with shaped interlocking profiles of a critical shape on the surface of the tube, (b) delivering separate flow streams of plastic to the profiles with the separate flow streams joining the main flow stream at the profiles of the die, (c) and cooling the plastc at a controlled rate to cool the tubing and the profiles.

Claim 4

The method of forming a continuous plastic tube with circumferentially spaced axially extending complementary interlocking profiles formed integrally therewith by extruding the tube through a die having an annular opening and profiles projecting therefrom comprising, (a) delivering a main flow stream of plastic to the annular opening in the die forming a tube with shaped interlocking profiles of a critical shape on the surface of the tube, (b) delivering separate flow streams of plastic to the profiles with the separate flow streams joining the main flow stream at the profiles of the die, (c) and cooling the plastc at a controlled rate to cool the tubing and the profiles.

Claim 5

The method of making a unitary container material which comprises, (a) extruding a one piece continuous closed tube having continuous axially extending .Iadd.male and female interlocking .Iaddend.closure elements integral therewith formed at circumferentially spaced locations on the tube surface and shaped for releasably interlocking with each other with said elements each projecting from one surface only of the tube, (b) .Iadd.directing a small amount of air into the tube to maintain the tube in its tubular shape, .Iaddend. .[.b.]. .Iadd.(c) directing a flow of outer cooling air annularly around the outer surface of the tube at a location where the tube has reached its final size and diameter after being extruded and after being filled with the air directed into the tube and .Iaddend.cooling the extruded tube at a rate so that said elements remain on the surface on which they appear and do not project on the opposite surface .Iadd.and so that the closure elements are cooled retaining their shape and size.Iaddend., .[.(c).]. .Iadd.(d) .Iaddend.and separating the tube longitudinally between said elements.

Claim 6

The method of making a unitary container material which comprises, (a) extruding a one piece continuous closed tube having continuous axially extending .Iadd.male and female interlocking .Iaddend.closure elements integral therewith formed at circumferentially spaced locations on the tube surface and shaped for releasably interlocking with each other with said elements each projecting from one surface only of the tube, (b) .Iadd.directing a small amount of air into the tube to maintain the tube in its tubular shape, .Iaddend. .[.b.]. .Iadd.(c) directing a flow of outer cooling air annularly around the outer surface of the tube at a location where the tube has reached its final size and diameter after being extruded and after being filled with the air directed into the tube and .Iaddend.cooling the extruded tube at a rate so that said elements remain on the surface on which they appear and do not project on the opposite surface .Iadd.and so that the closure elements are cooled retaining their shape and size.Iaddend., .[.(c).]. .Iadd.(d) .Iaddend.and separating the tube longitudinally between said elements.

Claim 7

The method of making a unitary container material which comprises, (a) extruding a one piece continuous closed tube of a heated plastic, (b) simultaneously extruding continuously axially extending .Iadd.male and female .Iaddend.interlocking elements shaped for cooperative pressure interengagement and for forcible separation with one having a shaped projection and the other a shaped groove, said elements spaced apart from each other in both circumferential directions and being further apart in one direction than the other, each element projecting from its one surface only of the tube and being integral with the tube material and extending therealong, (c) .Iadd.directing a small amount of air into the tube to maintain the tube in its tubular shape, .Iaddend. .[.(c).]. .Iadd.(d) .Iaddend.and .Iadd.directing a flow of outer cooling air annularly around the outer surface of the tube at a location where the tube has reached its final size and diameter after being extruded and after being filled with the air directed into the tube and .Iaddend.cooling the extruded plastic at a rate so that each of the elements remains on its one surface only and does not project from the other surface .Iadd.and so that the closure elements are cooled retaining their shape and size. .Iaddend.

Claim 8

The method of making a unitary container material which comprises, (a) extruding a one piece continuous closed tube of a heated plastic, (b) simultaneously extruding continuously axially extending .Iadd.male and female .Iaddend.interlocking elements shaped for cooperative pressure interengagement and for forcible separation with one having a shaped projection and the other a shaped groove, said elements spaced apart from each other in both circumferential directions and being further apart in one direction than the other, each element projecting from its one surface only of the tube and being integral with the tube material and extending therealong, (c) .Iadd.directing a small amount of air into the tube to maintain the tube in its tubular shape, .Iaddend. .[.(c).]. .Iadd.(d) .Iaddend.and .Iadd.directing a flow of outer cooling air annularly around the outer surface of the tube at a location where the tube has reached its final size and diameter after being extruded and after being filled with the air directed into the tube and .Iaddend.cooling the extruded plastic at a rate so that each of the elements remains on its one surface only and does not project from the other surface .Iadd.and so that the closure elements are cooled retaining their shape and size. .Iaddend.

Claim 9

The method of making a unitary container material which comprises, (a) extruding a one piece continuous closed tube of a heated plastic .Iadd.from an extruder head, .Iaddend. (b) simultaneously extruding a continuous axially extending .Iadd.male .Iaddend.fastener element shaped for cooperative pressure interengagement and for forcible separation with another .Iadd.female .Iaddend.interlocking element with the element being integral with the tube and projecting from one surface only and extending therealong, (c) and .Iadd.directing a flow of outer cooling air annularly around the outer surface of the tube at a location spaced axially from the extruder head .Iaddend.cooling the plastic after it is extruded at a rate so that the element remains on its one surface only and does not project from the other surface .Iadd.and so that the closure elements are cooled retaining their shape and size. .Iaddend.

Claim 10

The method of making a unitary container material which comprises, (a) extruding a one piece continuous closed tube of a heated plastic .Iadd.from an extruder head, .Iaddend. (b) simultaneously extruding a continuous axially extending .Iadd.male .Iaddend.fastener element shaped for cooperative pressure interengagement and for forcible separation with another .Iadd.female .Iaddend.interlocking element with the element being integral with the tube and projecting from one surface only and extending therealong, (c) and .Iadd.directing a flow of outer cooling air annularly around the outer surface of the tube at a location spaced axially from the extruder head .Iaddend.cooling the plastic after it is extruded at a rate so that the element remains on its one surface only and does not project from the other surface .Iadd.and so that the closure elements are cooled retaining their shape and size. .Iaddend.

Claim 11

The method of making a container material for use in forming a plurality of bags which comprises, (a) extruding a continuous closed annular heated plastic tube .Iadd.from an extruder head, .Iaddend. (b) simultaneously extruding a plurality of pairs of continuous axially extending .Iadd.male and female .Iaddend.interlocking elements integral with the tube and extending uniformly axially therealong with each of the interlocking elements projecting from one surface only of the tube, .[.and.]. .Iadd.(c) cooling the tube at a rate so that the elements remain on the surface of the tube on which they were initially formed, .Iaddend. .[.(c).]. .Iadd.(d) directing a flow of outer cooling air annularly around the outer surface of the tube at a location spaced axially from the extruder head .Iaddend.cooling the plastic after it is extruded at a rate so that the elements .[.remains.]. .Iadd.remain .Iaddend.on .[.its.]. one surface only and .[.does.]. .Iadd.do .Iaddend.not project from the outer surface .Iadd.and so that the closure elements are cooled retaining their shape and size, .Iaddend. .[.(d).]. .Iadd.(e) and drawing the tube axially after it has been extruded..Iaddend.

Claim 12

The method of making a container material for use in forming a plurality of bags which comprises, (a) extruding a continuous closed annular heated plastic tube .Iadd.from an extruder head, .Iaddend. (b) simultaneously extruding a plurality of pairs of continuous axially extending .Iadd.male and female .Iaddend.interlocking elements integral with the tube and extending uniformly axially therealong with each of the interlocking elements projecting from one surface only of the tube, .[.and.]. .Iadd.(c) cooling the tube at a rate so that the elements remain on the surface of the tube on which they were initially formed, .Iaddend. .[.(c).]. .Iadd.(d) directing a flow of outer cooling air annularly around the outer surface of the tube at a location spaced axially from the extruder head .Iaddend.cooling the plastic after it is extruded at a rate so that the elements .[.remains.]. .Iadd.remain .Iaddend.on .[.its.]. one surface only and .[.does.]. .Iadd.do .Iaddend.not project from the outer surface .Iadd.and so that the closure elements are cooled retaining their shape and size, .Iaddend. .[.(d).]. .Iadd.(e) and drawing the tube axially after it has been extruded..Iaddend.