Patterned sheet products
View Patent ↗This invention concerns patterned sheets for cleansing and other applications, of porous or absorbent material, in particular of a non-woven material, such as a wipe. It further relates to such a sheet to which a composition has been applied. The invention further concerns the manufacture and use of such products.
1. A non-woven sheet comprising a substrate wherein the non-woven sheet is obtained by carding, spunlaying, meltblowing, wetlaying or a mixture thereof as the web forming procedure and by hydro-entanglement as the web bonding process and wherein a substantial portion of one or both surfaces of the sheet has a three-dimensional pattern embossed therein, said pattern comprising a series of raised and lowered regions, wherein both surfaces have a ridged pattern and none of the raised or lowered regions has any flat portion; wherein the lowered and raised regions are arranged in a recurrent pattern of lowered and raised regions of about the same size and shape and wherein the basis weight of the substrate is essentially the same over the whole surface and wherein the density of the raised regions is in the range of from 20 to 120 kg/m 3 and the density of the lowered regions is in the range of from 120 to 180 kg/m 3 .
2. A non-woven sheet, according to claim 1 , obtained by:
providing a precursor substrate, —providing a forming member, having an image surface, and having a three-dimensional pattern engraved therein, said pattern comprising a series of raised and lowered regions, —advancing said precursor substrate onto said three-dimensional transfer device, and applying hydraulic energy to said precursor substrate to simultaneously entangle the fibers of the precursor substrate to furnish the substrate and impart a three-dimensional pattern to the substrate comprising a series of raised and lowered regions, wherein the basis weight of the substrate is essentially the same over the whole surface and wherein the density of the raised regions is lower than the density of the lowered regions.
3. The sheet according to claim 2 wherein the cross-sections of at least a portion of at least one lowered region predominantly exhibit a rounded shape being at least partially flattened at its bottom part.
4. The sheet according to claim 2 wherein the three dimensional pattern is present over the whole surface of the sheet and wherein the embossed pattern may be present at one surface or at both surfaces of the sheet.
5. The sheet according to claim 2 wherein the raised and lowered regions are located adjacent to one another.
6. The sheet according to claim 2 wherein the raised and lowered regions form one or more patterns that are present at one or at both surfaces of said sheet, wherein different patterns are adjacent to one another or are separated by areas that have no pattern.
7. The sheet according to claim 1 wherein the raised and lowered regions form a pattern of lines or stripes.
8. The sheet according to claim 1 wherein the raised and lowered regions run in parallel.
9. The sheet according to claim 1 wherein at least one of the surfaces of the sheet in a transversal section has a sinusoidal shape.
10. The sheet according to claim 1 wherein the width of the lowered and of the raised regions is substantially the same over the whole surface of the sheet.
11. The sheet according to claim 1 wherein the density of the lowered regions is in the range from 120 to 170 kg/m3 and wherein the density of the raised regions is in the range from 60 to 90 kg/m3.
12. The sheet according to claim 1 wherein the non-woven sheet is obtained by subjecting at least one fibrous layer of non-woven fibers to carding by use of at least one carding unit to produce a precursor substrate in a web forming step which is subjected to hydro-entanglement.
13. The sheet according to claim 1 wherein the non-woven sheet is obtained by subjecting at least one first fibrous layer of non-woven fibers to carding by use of at least one carding unit to produce a first precursor substrate layer, placing at least one second fibrous layer onto the first precursor substrate layer by airlaying, subjecting at least one third fibrous layer of non-woven fibers to carding by use of at least one carding unit and placing said third precursor substrate layer adjacent to the second precursor substrate layer, furnishing a precursor substrate which is subjected to hydro-entanglement.
14. The sheet according to claim 1 wherein said sheet is dry or impregnated and/or coated with a suitable composition.
15. The sheet according to claim 14 wherein the composition is an aqueous liquid or an oil-based liquid.