EDGE LAMINATED ROLL GOODS
A laminated article comprises a first web of material of a first width. A second web of material has a second width substantially equal to the first width. The second web is coextensive with the first web. The second web is laminated at a lateral portion to the first web. A permeable unlaminated portion extends transversely of the laminated lateral portion. The width of the laminated lateral portion is less than the half the first width.
1 . A laminated article comprising:
a first web of material having a first width;
a second web of material having a width substantially equal to the first width and coextensive with the first web, the second web laminated at a lateral portion to the first web; and
a permeable unlaminated portion extending transversely of the laminated lateral portion;
the width of the laminated lateral portion being less than the half the first width.
2 . The laminated article of claim 1 wherein the second web is laminated at opposite lateral portions to the first web and the unlaminated portion extending between the laminated lateral portions.
3 . The laminated article of claim 2 further including an intermediate laminated portion between the laminated lateral edges and extending for the length of the laminated article, the intermediate laminated portion selected from the group of having a width greater than the width of each of the laminated lateral portions, having a width less than the width of each of the laminated lateral portions and having an alternating series of unlaminated portions and laminated portions.
4 . The laminated article of claim 1 wherein one of the first and second webs of material is a microporous membrane.
5 . The laminated article of claim 3 wherein the microporous membrane comprises expanded polytetrafluoroethylene.
6 . The laminated article of claim 1 wherein the first and second webs of material are thermally laminated together.
7 . The laminated article of claim 1 wherein the first and second webs of material are continuously laminated together at respective outermost lateral edges of the laminated article.
8 . The laminated article of claim 1 wherein one of the first and second webs of material is a meltblown ethylene chlorotrifluoroethlyene.
9 . The laminated article of claim 1 wherein the width of each of the laminated lateral portions is less than the 15 percent of the first width.
10 . A laminated article comprising:
a first layer of expanded polytetrafluoroethylene having a first width;
a second layer of meltblown ethylene chlorotrifluoroethlyene fabric having a width substantially equal to the first width, the first and second layers being coextensive, the second layer continuously laminated at opposite lateral portions to the first layer; and
a permeable unlaminated portion extending between the laminated lateral portions;
the width of each of the laminated lateral portions being less than the half the first width.
11 . The laminated article of claim 10 wherein the first and second layers of material are thermally laminated together.
12 . The laminated article of claim 10 wherein the first and second layers of material are laminated together at respective outermost lateral edges of the laminated article.
13 . The laminated web of claim 10 wherein at least one of the laminated lateral portions includes a continuous strip of lamination between the fabric and expanded polytetrafluoroethylene layers.
14 . The laminated article of claim 10 wherein the width of each of the laminated lateral portions is less than the 15 percent of the first width.
15 . A method of laminating sheet material, the method comprising the steps of:
providing a first web of material having a first width;
providing a second web of material having a width substantially equal to the first width; and
laminating the second layer to the first layer at opposite lateral portions;
in which a permeable unlaminated portion extends between the laminated lateral portions; and
the width of each of the laminated lateral portions is less than the half the first width.
16 . The method of claim 15 wherein one of the first and second webs of material is a microporous membrane.
17 . The method of claim 16 wherein the microporous membrane comprises expanded polytetrafluoroethylene.
18 . The method of claim 15 wherein the first and second webs of material are continuously thermally laminated together at respective outermost lateral edges of the laminated web.
19 . The method of claim 18 wherein the first and second webs of material are laminated together by a roll having raised portions of a width approximately equal to the width of the laminated lateral portions.
20 . The method of claim 15 wherein one of the first and second webs of material is a meltblown ethylene chlorotrifluoroethlyene.