Claims
- 1. A process for bonding and enhancing the bulk of a highly bulked low strength fibrous web, comprising the steps of:
- (a) passing a highly bulked, low strength fibrous substrate web, which has low internal fiber bonding such that creping of the substrate will tend to separate and fluff up the fibers, into a nip between a gravure roller and an impression roller, the impression roller having a resilient surface with raised areas defining an interconnected network and depressed areas between the raised areas such that the web is compressed under the raised areas of the impression roller and the remainder of the web is left substantially uncompressed, the height of the raised areas above the depressed areas selected to be greater than the uncompressed thickness of the substrate web, the gravure roller having depressions which carry binding liquid in a pattern which underlies and registers with the raised areas on the impression roller such that binding liquid is absorbed substantially through the compressed areas of the web while the other areas of the web receive substantially no binding liquid;
- (b) applying the web to a heated, moving creping surface with a pressure roller having raised areas and depressed areas to define a pattern therein, the height of the raised areas above the depressed areas selected to be greater than the uncompressed thickness of the substrate web, the web being compressed only by the raised areas of the pressure roller with the binding liquid coated side of the web against the creping surface to cause the web to adhere thereto with the binding liquid; and
- (c) creping the web by removing it from the creping surface with a creping blade such that the bulk of the web so creped is greater than the bulk of the substrate web.
- 2. A process for bonding and enhancing the bulk of a highly bulked, low strength fibrous substrate web, comprising the steps of:
- (a) passing a highly bulked, low strength fibrous substrate web, which has low internal fiber bonding such that creping of the substrate will tend to separate and fluff up the fibers, into a nip between a gravure roller and an impression roller, the gravure roller providing binding liquid on its surface to one side of the web, and the impression roller having a resilient surface with raised areas defining an interconnected network and depressed areas between the raised areas such that the web is compressed under the raised areas of the impression roller and the remainder of the web is left substantially uncompressed, the height of the raised areas above the depressed areas selected to be greater than the uncompressed thickness of the substrate web, the binding liquid on the surface of the gravure roller being absorbed substantially through the compressed areas of the web;
- (b) applying the web to a heated, moving creping surface with a pressure roller having raised areas and depressed areas to define a pattern therein, the height of the raised areas above the depressed areas selected to be greater than the uncompressed thickness of the substrate web, the web being compressed only by the raised areas of the pressure roller with the binding liquid coated side of the web against the creping surface to cause the web to adhere thereto with the binding liquid; and
- (c) creping the web by removing it from the creping surface with a creping blade such that the bulk of the web so creped is greater than the bulk of the substrate web.
- 3. A process for bonding and enhancing the bulk of a highly bulked, low strength fibrous substrate web, comprising the steps of:
- (a) passing a highly bulked, low strength fibrous substrate web, which has low internal fiber bonding such that creping of the substrate will tend to separate and fluff up the fibers, into a nip between a gravure roller and an impression roller, the gravure roller providing binding liquid on its surface to one side of the web, and the impression roller having a resilient surface with raised areas defining an interconnected network and depressed areas between the raised areas such that the web is compressed under the raised areas of the impression roller and the remainder of the web is left substantially uncompressed, the height of the raised areas above the depressed areas selected to be greater than the uncompressed thickness of the substrate web, the binding liquid on the surface of the gravure roller being absorbed substantially through the compressed areas of the web;
- (b) rotating the impression roller and maintaining the compressed and uncompressed areas of the web in respective registry with the raised and depressed areas on the impression roller as it rotates;
- (c) passing the web on the impression roller into a nip formed between the impression roller and a moving, heated creping surface such that the raised areas of the impression roller press the once compressed areas of the web against the creping surface to adhere the web thereto with the binding liquid; and
- (d) creping the web by removing it from the creping surface with a creping blade such that the bulk of the web so creped is greater than the bulk of the substrate web.
- 4. A process for bonding and enhancing the bulk of a highly bulked, low strength fibrous substrate web, comprising the steps of:
- (a) passing a highly bulked, low strength fibrous substrate web, which has low internal fiber bonding such that creping of the substrate will tend to separate and fluff up the fibers, into a nip between a gravure roller and an impression roller, the gravure roller providing binding liquid on its surface to one side of the web, and the impression roller having a resilient surface with raised areas defining an interconnected network and depressed areas between the raised areas such that the web is compressed under the raised areas of the impression roller and the remainder of the web is left substantially uncompressed, the height of the raised areas above the depressed areas selected to be greater than the uncompressed thickness of the substrate web, the binding liquid on the surface of the gravure roller being absorbed substantially through the compressed areas of the web;
- (b) passing heated air through the binding liquid coated web to substantially dry it;
- (c) passing the dried web into a nip formed between a gravure roller and an impression roller, the gravure roller providing binding liquid on its surface to the side of the web opposite that to which binding liquid had previously been applied, and the impression roller having raised areas defining an interconnected network and depressed areas between the raised areas such that the web is compressed under the raised areas of the impression roller and the remainder of the web is left substantially uncompressed by the impression roller, the height of the raised areas above the depressed areas selected to be greater than the uncompressed thickness of the substrate web, the binding liquid on the surface of the gravure roller being absorbed substantially through the compressed areas of the web;
- (d) applying the web to a heated, moving creping surface with a pressure roller having raised areas and depressed areas to define a pattern therein, the height of the raised areas above the depressed areas selected to be greater than the uncompressed thickness of the substrate web, the web being compressed only by the raised areas of the pressure roller with the binding liquid coated side of the web against the creping surface to cause the web to adhere thereto with the binding liquid; and
- (e) creping the web by removing it from the creping surface with a creping blade such that the bulk of the web so creped is greater than the bulk of the substrate web.
- 5. A process for bonding and enhancing the bulk of a highly bulked, low strength fibrous substrate web, comprising the steps of:
- (a) passing a highly bulked, low strength fibrous substrate web, which has low internal fiber bonding such that creping of the substrate will tend to separate and fluff up the fibers, into a nip between a gravure roller and an impression roller, the gravure roller providing binding liquid on its surface to one side of the web, and the impression roller having a resilient surface with raised areas defining an interconnected network and depressed areas between the raised areas such that the web is compressed under the raised areas of the impression roller and the remainder of the web is left substantially uncompressed, the height of the raised areas above the depressed areas selected to be greater than the uncompressed thickness of the substrate web, the binding liquid on the surface of the gravure roller being absorbed substantially through the compressed areas of the web;
- (b) applying the web to a heated, moving creping surface with pressure applied by a pressure roller having raised areas and depressed areas to define a pattern therein, the height of the raised areas above the depressed areas selected to be greater than the uncompressed thickness of the substrate web, the web being compressed only by the raised areas of the pressure roller with the binding liquid coated side of the web against the creping surface to cause the web to adhere thereto with the binding liquid;
- (c) creping the web by removing it from the creping surface with a creping blade;
- (d) passing the creped web into a nip between a second gravure roller and a second impression roller, the second gravure roller providing binding liquid on its surface to the side of the web opposite that to which binding liquid had previously been applied, and the second impression roller having a resilient surface with raised areas defining an interconnected network and depressed areas between the raised areas such that the web is compressed under the raised areas of the second impression roller and the remainder of the web is left substantially uncompressed by the second impression roller, the height of the raised areas above the depressed areas selected to be greater than the uncompressed thickness of the substrate web, the binding liquid on the surface of the second gravure roller being absorbed substantially through the areas of the web compressed by the second impression roller;
- (e) applying the web to a heated, moving creping surface with pressure applied by a pressure roller having raised areas and depressed areas to define a pattern therein, the height of the raised areas above the depressed areas selected to be greater than the uncompressed thickness of the substrate web, the web being compressed only by the raised areas of the pressure roller with the binding liquid coated side of web against the creping surface to cause the web to adhere thereto with the binding liquid; and
- (f) creping the web by removing it from the creping surface with a creping blade, such that the bulk of the web so creped is greater than the bulk of the substrate web.
- 6. A process for bonding and enhancing the bulk of a highly bulked, low strength fibrous substrate web, comprising the steps of:
- (a) passing a highly bulked, low strength fibrous substrate web, which has low internal fiber bonding such that creping of the substrate will tend to separate and fluff up the fibers, into a nip between a gravure roller and an impression roller, the gravure roller providing binding liquid on its surface to one side of the web, and the impression roller having a resilient surface with raised areas defining an interconnected network and depressed areas between the raised areas such that the web is compressed under the raised areas of the impression roller and the remainder of the web is left substantially uncompressed, the height of the raised areas above the depressed areas selected to be greater than the uncompressed thickness of the substrate web, the binding liquid on the surface of the gravure roller being absorbed substantially through the compressed areas of the web;
- (b) rotating the impression roller and maintaining the compressed and uncompressed areas of the web in respective registry with the raised and depressed areas on the impression roller as it rotates;
- (c) passing the web on the impression roller into a nip formed between the impression roller and moving, heated creping surface such that the raised areas of the impression roller press the once compressed areas of the web against the creping surface to adhere the web thereto with the binding liquid;
- (d) creping the web by removing it from the creping surface with a creping blade;
- (e) passing the creped web into a nip between a second gravure roller and a second impression roller, the second gravure roller providing binding liquid on its surface to the side of the web opposite that to which binding liquid had previously been applied, and the second impression roller having a resilient surface with raised areas defining an interconnected network and depressed areas between the raised areas such that the web is compressed under the raised areas of the second impression roller and the remainder of the web is left substantially uncompressed by the second impression roller, the height of the raised areas above the depressed areas selected to be greater than the uncompressed thickness of the substrate web, the binding liquid on the surface of the second gravure roller being absorbed substantially through the areas of the web compressed by the second impression roller;
- (f) rotating the second impression roller and maintaining the compressed and uncompressed areas of the web in respective registry with the raised and depressed areas on the second impression roller as it rotates;
- (g) passing the web on the second impression roller into a nip formed between the second impression roller and a moving, heated creping surface such that the raised areas of the second impression roller press the once compressed areas of the web against the creping surface to adhere the web thereto with the binding liquid; and
- (h) creping the web by removing it from the creping surface with a creping blade such that the bulk of the web so creped is greater than the bulk of the substrate web.
- 7. The process of claim 2, 3 or 4 wherein the raised area of the impression roller is between 20% and 40% of the total area of the surface of the roller.
- 8. The process of claim 1, 2, 3 or 4 wherein the binding liquid is capable of being cured to a hardened and insoluble state, and further including the step of curing the binding liquid in the creped web to thereby provide lines of strength in the web corresponding to the interconnected networks of cured binding liquid in the web.
- 9. The process of claim 5 or 6 wherein the binding liquid is capable of being cured to a hardened and insoluble state, and further including the step of curing the binding liquid in the creped web to thereby provide lines of strength in the web corresponding to the interconnected networks of cured binding liquid in the web.
- 10. The process of claim 8 wherein the binding liquid is heat curable, and wherein the step of curing the binding liquid comprises applying hot air to the creped web for a time sufficient to cure the binding liquid.
- 11. The process of claim 10 wherein the binding liquid includes a mixture of ethylene vinyl acetate polymer and acrylic polymer.
- 12. The process of claim 9 wherein the binding liquid is heat curable to a hardened and insoluble state, and wherein the step of curing the binder liquid comprises applying hot air to the creped web for a time sufficient to cure the binding liquid.
- 13. The process of claim 12 wherein the binding liquid includes a mixture of ethylene vinyl acetate polymer and acrylic polymer.
- 14. The process of claim 2, 3 or 4 wherein the raised areas on the impression roller define a rectilinear network pattern which surround depressed areas having a quadrangular shape.
- 15. The process of claim 1 wherein the interconnected network of areas compressed in the web defines a rectilinear network pattern.
- 16. The process of claim 1 wherein the step of applying the web to the creping surface includes passing the web having a coating of binding liquid thereon into a nip between a pressure roller and the moving creping surface.
- 17. The process of claim 16 wherein the pressure roller has raised areas and depressed areas to define a pattern therein, with the web being compressed by the raised areas of the pressure roller.
- 18. The process of claim 2, 3, 4, 5 or 6 in which each gravure roller has a uniform surface composed of cells acting as reservoirs for binding liquid, the binding liquid being absorbed substantially through the areas of the web which are compressed against each gravure roller, and coated on the surface of the areas of the web which are not so compressed.
- 19. The process of claim 2, 3, 4, 5 or 6 in which each gravure roller has depressions on its surface acting as reservoirs for binding liquid and arranged in a pattern which matches and registers with the raised areas of the impression roller which presses the web against the gravure roller, the areas of the gravure roller between the pattern areas being smooth so as not to pick up binding liquid, such that the binding liquid is substantially absorbed through those areas of the web which are compressed against the gravure roller while the remainder of the web receives no binding liquid from the gravure roller.
Parent Case Info
This application is a continuation in part of prior application Ser. No. 182,834, filed Aug. 29, 1980 now abandoned.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
4000237 |
Roberts |
Dec 1976 |
|
4125659 |
Klowak et al. |
Nov 1978 |
|
4135024 |
Callahan et al. |
Jan 1979 |
|
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
182834 |
Aug 1980 |
|