Forming laminated touch fasteners
A laminated touch fastener is made in a continuous process on a mold roll. Flowable resin is pressed against the mold roll in limited areas to form projections extending from resin layers that are laminated to a flexible substrate while carried on the mold roll. In one example a continuous channel about the mold roll is positioned such that the resin at least partially fills the channel as the layers are formed, thereby forming in the channel a raised portion in which the resin layer is of a greater thickness than at a point between the projections and the raised portion. In another example, grooves in the mold roll receive ribs of a pressure applicator during forming of the layers, the ribs blocking lateral flow of the resin to form a desired edge profile.
1. A touch fastener product comprising
a flexible, sheet-form substrate having a broad surface;
a layer of resin directly laminated to the broad surface, the layer of resin covering only a portion of the broad surface and defining a layer edge ending at a lateralmost surface adjacent an exposed region of the broad surface and extending away from the broad surface of the substrate; and
an array of discrete fastener projections extending from the layer of resin;
wherein the layer of resin is of a greater thickness at the lateralmost surface than at a point between the array and the layer edge.
2. The product of claim 1 , wherein the layer edge comprises a rib, and wherein the layer defines a selvedge area extending from the fastener projection array to the rib, the selvedge area being of a thickness less than a thickness of the resin layer at the rib.
3. The product of claim 2 , wherein the rib is shorter than the fastener elements.
4. The product of claim 2 , wherein the rib has a rounded or chamfered outer edge.
5. The product of claim 2 , wherein the rib has a height, measured from the resin layer in the selvedge area, which is between about 20 and 35 percent of a width of the rib.
6. The product of claim 1 , wherein the substrate is longitudinally continuous and the layer of resin forms a discrete band of resin running along a length of the substrate.
7. The product of claim 1 , wherein the layer of resin covers only a bounded area of the broad substrate surface, surrounded by the exposed region of the broad surface, the layer edge comprising a rib extending about a periphery of the resin layer.
8. The product of claim 2 , wherein the rib has a free-form upper surface.
9. The product of claim 1 , wherein the substrate surface is fibrous.
10. The product of claim 9 , wherein the substrate surface is porous, defining pores between substrate fibers.
11. The product of claim 10 , wherein resin of the layer of resin is embedded within the pores of the substrate surface.
12. The product of claim 1 , wherein the substrate surface is of a topography that undulates across the surface, the layer edge traversing undulations of the surface.
13. The product of claim 1 , wherein the layer of resin is of a thickness at the layer edge that is between about two and four times a thickness of the layer at a point between the array and the layer edge.
14. The product of claim 1 , wherein the layer edge follows a serpentine path along the substrate surface.
15. A touch fastener product comprising
a flexible, sheet-form substrate having a broad surface;
a layer of resin directly laminated to the broad surface, the layer of resin covering only a portion of the broad surface and defining a layer edge adjacent an exposed region of the broad surface; and
an array of discrete fastener projections extending from the layer of resin;
wherein the layer of resin is of a greater thickness at the layer edge than at a point between the array and the layer edge;
wherein the layer edge comprises a rib, and wherein the layer defines a selvedge area extending from the fastener projection array to the rib, the selvedge area being of a thickness less than a thickness of the resin layer at the rib; and
wherein the rib has a height, measured from the resin layer in the selvedge area, which is between about 20 and 35 percent of a width of the rib.
16. The product of claim 15 , wherein the substrate surface is of a topography that undulates across the surface, the layer edge traversing undulations of the surface.
17. The product of claim 15 , wherein the substrate is longitudinally continuous and the layer of resin forms a discrete band of resin running along a length of the substrate.
18. A touch fastener product comprising
a flexible, sheet-form substrate having a broad surface;
a layer of resin directly laminated to the broad surface, the layer of resin covering only a portion of the broad surface and defining a layer edge adjacent an exposed region of the broad surface; and
an array of discrete fastener projections extending from the layer of resin;
wherein the layer of resin is of a greater thickness at the layer edge than at a point between the array and the layer edge;
wherein the layer of resin is of a thickness at the layer edge that is between about two and four times a thickness of the layer at a point between the array and the layer edge.
19. The product of claim 18 , wherein the layer edge comprises a rib, and wherein the layer defines a selvedge area extending from the fastener projection array to the rib, the selvedge area being of a thickness less than a thickness of the resin layer at the rib.
20. The product of claim 18 , wherein the substrate is longitudinally continuous and the layer of resin forms a discrete band of resin running along a length of the substrate.