초록 ▼

The present invention relates to methods of producing color change in overlapping layers of material. The method comprises providing a first layer having a first activatable colorant and a second layer having a second activatable colorant. A first external stimulus is applied to activate the first a

The present invention relates to methods of producing color change in overlapping layers of material. The method comprises providing a first layer having a first activatable colorant and a second layer having a second activatable colorant. A first external stimulus is applied to activate the first activatable colorant and produce a first activated color region in the first layer. A second external stimulus is applied to activate second activatable colorant and produce a second activated color region in the second layer.

대표청구항 ▼

1. A method of producing color change in overlapping web layers comprising the steps of; a. providing a first web layer comprising a first activatable colorant;b. applying a first external stimulus to the first web layer to activate the first activatable colorant in the first web layer producing a f

1. A method of producing color change in overlapping web layers comprising the steps of; a. providing a first web layer comprising a first activatable colorant;b. applying a first external stimulus to the first web layer to activate the first activatable colorant in the first web layer producing a first activated color region in the first web layer, wherein said first external stimulus comprises UV light;c. providing a second layer comprising a second activatable colorant wherein the second layer overlaps the first web layer;d. applying a second external stimulus to the overlapping layers to activate the second activatable colorant in the second layer producing a second activated color region in the second layer, wherein said second external stimulus comprises UV light. 2. The method of claim 1 wherein the first and second external stimuli are applied sequentially, one after another. 3. The method of claim 2 wherein the first external stimulus is applied through the second layer, activating the first activatable colorant in the first layer and not activating the second activatable colorant in the second layer. 4. The method of claim 1 wherein the first and second external stimuli are applied simultaneously, activating the first and second activatable colorants at the same time. 5. A method of producing color change in overlapping web layers comprising the steps of; a. providing a first web layer comprising a first activatable colorant;b. applying a first external stimulus to the first web layer to activate the first activatable colorant in the first web layer producing a first activated color region in the first web layer, wherein said first external stimulus comprises UV light;c. providing a second web layer comprising a second activatable colorant;d. applying a second external stimulus to the second web layer to activate the second activatable colorant in the second web layer producing a second activated color region in the second web layer, wherein said second external stimulus comprises UV light;e. conveying the first and second web layers in a machine direction; andf. combining the first and second web layers wherein the second web layer overlaps the first web layer. 6. The method of claim 1, wherein the first and second layers are selected from the group consisting of films, nonwovens, air laids, fibers, filaments, adhesives, lotions, absorbent gelling materials, and foams. 7. The method of claim 1 wherein the first and second layers form layers of an absorbent article selected from the group consisting of diapers, sanitary napkins, tampons, panty liners, incontinence devices, and wipes. 8. The method of claim 5 wherein the first and second external stimuli are applied sequentially, one after another. 9. The method of claim 5 wherein the first external stimulus is applied through the second layer, activating the first activatable colorant in the first layer and not activating the second activatable colorant in the second layer. 10. The method of claim 5 wherein the first and second external stimuli are applied simultaneously, activating the first and second activatable colorants at the same time. 11. The method of claim 5 wherein the first and second layers are selected from the group consisting of films, nonwovens, air laids, fibers, filaments, adhesives, lotions, absorbent gelling materials, and foams. 12. The method of claim 5 wherein the first and second layers form layers of an absorbent article selected from the group consisting of diapers, sanitary napkins, tampons, panty liners, incontinence devices, and wipes.