Cloth-like tissue sheets having camouflaged texture
View Patent ↗Embossing regularly textured sheets with an appropriate regular, discrete embossing pattern to improve softness can result in a combined texture that creates an interference pattern that camouflages the original texture pattern and the embossing pattern. The resulting pattern is more appealing to the eye and is more random in appearance than the initial textured sheet or the embossing pattern individually. This result is particularly advantageous for paper towels.
1. A tissue sheet having a surface texture characterized by 24 or fewer primary polar spatial frequencies greater than 0.2 mm −1 where the primary polar spatial frequencies have Fourier magnitudes greater than 5 times the average Fourier magnitude for the tissue surface and are limited in number to those with Fourier magnitudes of 20 percent or more of the special frequency with the largest Fourier magnitude, such that no two of the primary Fourier magnitudes have absolute frequency differences less than 0.1 mm −1 .
2. The tissue sheet of claim 1 wherein the number of primary polar spatial frequencies is 12 or fewer.
3. The tissue sheet of claim 1 wherein the primary polar spatial frequencies are limited in number to those with magnitudes of 30 percent or more of the spatial frequency with the largest magnitude.
4. The tissue sheet of claim 1 wherein the primary polar spatial frequencies are limited in number to those with magnitudes of 40 percent or more of the spatial frequency with the largest magnitude.
5. The tissue sheet of claim 1 , 2 , 3 or 4 wherein the primary polar spatial frequencies all have Fourier magnitudes 10 or more times the average Fourier magnitude for the tissue surface.
6. The tissue sheet of claim 1 , 2 , 3 or 4 wherein the primary polar spatial frequencies all have Fourier magnitudes 20 or more times the average Fourier magnitude for the tissue surface.
7. The tissue sheet of claim 1 wherein no two of the primary Fourier magnitudes have absolute frequency differences of 0.075 mm −1 or less.
8. The tissue sheet of claim 1 wherein no two of the primary Fourier magnitudes have absolute frequency differences of 0.05 mm −1 or less.
9. The tissue sheet of claim 1 wherein the sheet is an airlaid sheet.