1. An extrusion head configured for at least one extruder, the extrusion head comprising:
a flow channel;
a finishing die; and
an opening in operative communication with the flow channel, wherein the opening is configured to at least partially accommodate a screw shaft of an additional extruder.
2. The extrusion head as recited in claim 1, further comprising an overlapping piece disposed between the finishing die and the flow channel, wherein the opening is in operative communication with the overlapping piece.
3. The extrusion head as recited in claim 1, further comprising an additional flow channel disposed inside of the flow channel, wherein the opening communicates with the additional flow channel.
4. The extrusion head as recited in claim 1, further comprising at least two head parts moveable with respect to each other, wherein the opening is disposed in at least one head part.
5. The extrusion head as recited in claim 1, wherein the opening is cylindrical.
6. The extrusion head as recited in claim 1, further comprising a cylinder sleeve disposed in the opening so as to at least partially accommodate the screw shaft.
7. The extrusion head as recited in claim 6, wherein the cylinder sleeve is a reducing sleeve.
8. The extrusion head as recited in claim 3, wherein the opening and the additional flow channel form an acute angle.
9. The extrusion head as recited in claim 1, wherein the opening is disposed parallel to a front of the extrusion head.
10. The extrusion head as recited in claim 1, wherein the opening is disposed parallel to one of the at least two head parts.
11. The extrusion head as recited in claim 1, further comprising a cylinder sleeve disposed in the opening so as to at least partially accommodate the screw shaft.
12. The extrusion head as recited in claim 1, further comprising a closing device configured to close the opening at one of the flow channel and the overlapping piece.
13. The extrusion device comprising:
at least one extruder;
an extrusion head including a flow channel, a finishing die and an opening in operative communication with the flow channel, wherein the opening is configured to at least partially accommodate a screw shaft of an additional extruder.
14. The extrusion device as recited in claim 13, wherein the extrusion head includes an overlapping piece disposed between the finishing die and the flow channel, wherein the opening is in operative communication with the overlapping piece.
15. The extrusion device as recited in claim 13, wherein the extrusion head includes an additional flow channel, wherein the opening communicates with the additional flow channel disposed inside of the flow channel.
16. The extrusion device as recited in claim 13, wherein the extrusion head includes at least two head parts moveable with respect to each other, wherein the opening is disposed in at least one head part.
17. The extrusion device as recited in claim 13, wherein the opening is cylindrical.
18. The extrusion device as recited in claim 13, wherein the extrusion head includes a cylinder sleeve disposed in the opening so as to at least partially accommodate the screw shaft.
19. The extrusion device as recited in claim 18, wherein the cylinder sleeve is a reducing sleeve.
20. The extrusion device as recited in claim 15, wherein the opening and the additional flow channel form an acute angle.
21. The extrusion device as recited in claim 13, wherein the opening is disposed parallel to a front of the extrusion head.
22. The extrusion device as recited in claim 13, wherein the opening is disposed parallel to one of the at least two head parts.
23. The extrusion device as recited in claim 13, wherein the extrusion head includes a cylinder sleeve disposed in the opening so as to at least partially accommodate the screw shaft.
24. The extrusion device as recited in claim 13, wherein the extrusion head includes a closing device configured to close the opening at one of the flow channel and the overlapping piece.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An absorbent material, comprising:
a substantially homogeneous blend of cellulosic fibrous material and particulate superabsorbent polymeric material, in the form of a sheet of absorbent material having upper and lower surfaces, said sheet of absorbent material including regions of relatively high densification formed at particles of said superabsorbent polymeric material,
said sheet of absorbent material including a wax having a discontinuous distribution in said sheet of absorbent material, including localized concentrations or penetrations of said wax in at least some of the regions of relatively high densification of said sheet of absorbent material, said wax having a melting point less than 100\xb0 C.,
wherein said sheet of absorbent material defines a pattern of regions of relatively high and low densification, said wax being preferentially distributed in said regions of high densification, said sheet of absorbent material having a basis weight in the range from about 75-700 gsm, with said superabsorbent polymeric material in a range of about 0-55%, by weight, and said wax in a range of about 2-15%, by weight.
2. An absorbent material in accordance with claim 1, wherein:
continuities of relatively higher concentrations of said wax extend in laterally spaced relationship to each other.
3. An absorbent material, comprising:
a blend of cellulosic fibrous material, superabsorbent polymeric material, and wax, in the form of a sheet of absorbent material having upper and lower surfaces,
wherein said sheet of absorbent material exhibits a centrifuge retention of at least 30 gramsgrams per weight percent, in decimal form, of said superabsorbent polymeric material,
wherein said absorbent material has a non-uniform distribution of wax, with continuities of relatively higher concentrations or penetrations of said wax extending in at least one of thickness, length and width directions of said sheet of absorbent material, said sheet of absorbent material having a basis weight in the range from about 75-700 gsm, with said superabsorbent polymeric material in a range of about 0-55%, by weight, and said wax in a range of about 2-15%, by weight.
4. An absorbent material in accordance with claim 3, wherein:
hydrogen bonding provides said sheet of absorbent material with a dry tensile strength of at least 10 Newton50 mm.
5. An absorbent material in accordance with claim 3, including:
at least one tissue layer applied to at least one of the upper and lower surfaces of said sheet of absorbent material.
6. An absorbent material, comprising:
a blend of cellulosic fibrous material, superabsorbent polymeric material, and a wax having a melting point less than 100\xb0 C., in the form of a sheet of absorbent material having upper and lower surfaces, that has non-trivial wet shear and wet tensile strengths
wherein said material exhibits a centrifuge retention value greater than 80% of a centrifuge retention value of a sheet of material having a like blend of cellulosic fibrous material and superabsorbent polymeric material without any wax content,
wherein said sheet of absorbent material has a basis weight in the range from about 50-1500 gsm, with said superabsorbent polymeric material in a range of about 0-70%, by weight, and said wax in a range of about 0.1-20%, by weight.
7. An absorbent material in accordance with claim 6, wherein:
said centrifuge retention value of said sheet of absorbent material is greater than 30 gramsgrams per weight percent, in decimal form, of superabsorbent polymeric material content in said sheet.
8. An absorbent material in accordance with claim 6, wherein:
hydrogen bonding provides said sheet of absorbent material with a dry tensile strength of at least 10 Newton50 mm.
9. An absorbent material in accordance with claim 6, wherein:
said sheet of absorbent material is airlaid, and bonded by the application of heat and pressure to said blend of cellulosic fibrous material, superabsorbent polymeric material, and said wax.
10. An absorbent material in accordance with claim 6, wherein:
said absorbent material has a non-uniform distribution of said wax.
11. An absorbent material in accordance with claim 6, wherein:
said absorbent material has a non-uniform distribution of wax, with continuities of relatively higher concentrations or penetrations of said wax extending in at least one of thickness, length and width directions of said sheet of absorbent material.
12. An absorbent material in accordance with claim 6, wherein:
said sheet of absorbent material has a basis weight in the range from about 75-700 gsm, with said superabsorbent polymeric material in a range of about 0-55%, by weight, and said wax in a range of about 2-15%, by weight.
13. A method of making an absorbent material in accordance with claim 10, including:
applying heat to said blend during said compacting step.
14. A method of making an absorbent material, comprising the steps:
airlaying a substantially homogeneous blend of cellulosic fibrous material and superabsorbent polymeric material;
compacting said blend to form a sheet of absorbent material having upper and lower surfaces, said sheet of absorbent material including regions of relatively high densification formed at particles of superabsorbent polymeric material; and
applying a discontinuous distribution of wax to said blend, to produce a sheet of absorbent material, including localized concentrations or penetrations of said wax in at least some of the regions of relatively high densification which exhibits a centrifuge retention value greater than 80% of a centrifuge retention value of a sheet of material having a like blend of cellulosic fibrous material and superabsorbent polymeric material without any wax content,
wherein said sheet of absorbent material has a basis weight in the range from about 75-700 gsm, with said superabsorbent polymeric material in a range of about 0-55%, by weight, and said wax in a range of about 2-15%, by weight.
15. A method of making an absorbent material in accordance with claim 14, wherein:
said centrifuge retention value of said sheet of absorbent material is greater than 30 gramsgrams per weight percent, in decimal form, of superabsorbent polymeric material.
16. A method of making an absorbent material in accordance with claim 14, wherein:
said absorbent material has a non-uniform distribution of wax, with continuities of relatively higher concentrations of said wax extending in at least one of thickness, length and width directions of said sheet of absorbent material.
17. A method of making an absorbent material in accordance with claim 16, wherein:
said continuities of relatively higher concentrations or penetrations of said wax extending in laterally spaced relationship to each other in a machine direction of said sheet of absorbent material.
18. A method of making an absorbent material in accordance with claim 14, wherein:
during said compacting step, said blend is compacted by cooperating calender rollers,
said step of applying wax being effected by application of said wax to at least one of said calender rollers so that said wax is transferred and applied to said blend.
19. A method of making an absorbent material comprising the steps of:
airlaying a substantially homogeneous blend of cellulosic fibrous material and particulate superabsorbent polymeric material;
compacting said blend to form a sheet of absorbent material having upper and lower surfaces, including forming said sheet of absorbent material with regions of relatively high densification about particles of said superabsorbent polymeric material; and
applying a discontinuous distribution of said wax in said sheet of absorbent material to form localized concentrations of said wax in at least some regions of relatively high densification of said sheet of absorbent material, wherein said sheet of absorbent material has a basis weight in the range from about 75-750 gsm, with said superabsorbent polymeric material in a range of about 0-55%, by weight, and said wax in a range of about 2-15%, by weight.
20. A method of making an absorbent material in accordance with claim 19, including:
compacting said blend with at least one calender roller operating at a temperature greater than 100 degrees C., and applying said wax to said sheet by application of said wax to said calender roller for transfer and application of said wax to said sheet of absorbent material.
21. A method of making an absorbent material in accordance with claim 20, wherein:
said calender roller has a pattern thereon to form regions of relatively high densification in said sheet of material, said wax being preferentially applied to said pattern on said calendar roller so that said wax is preferentially distributed to said regions of relatively high densification in said sheet of absorbent material.