Fibrous absorbent material and methods of making the same

A method of producing a low-density absorbent fibrous structure comprising:

• a) combining hydrophilic fibers with a structuring composition to form a mixture, said structuring composition comprising a substantially latex-free binder material and a removable phase;
• b) rearranging said fibers in a three-dimensional structure within said mixture;
• c) removing a portion of said removable phase;
• and
• d) binding said fibers together into a continuous, porous network, wherein said binder material forms bonds between said fibers to stabilize said porous network.

A method of producing a low-density absorbent fibrous structure comprising:

• a) coating hydrophobic fibers with a hydrophilic fiber coating material;
• b) combining said fibers with a structuring composition comprising a substantially latex-free binder material and a removable phase to form a mixture;
• c) producing a foam within said mixture;
• and
• d) binding said fibers together into a continuous, porous network, wherein said binder material stabilizes the porous network, and wherein at least about 20% of the surface area of said hydrophobic fibers is coated with hydrophilic material.

A method of producing a low-density absorbent fibrous structure comprising:

• a) combining hydrophilic fibers having a consistency greater than 30% with a structuring composition to form a mixture, said structuring composition comprising a non-gaseous phase and a removable phase;
• b) producing a foam within said mixture;
• and
• c) forming water-insoluble bonds with a binder material to bind said fibers together into a continuous, porous structure.

A method for producing a continuous absorbent fibrous structure comprising:

• a) combining hydrophilic fibers having a consistency greater than 30% with a structuring composition comprising a binder material and a removable phase to form a mixture;
• b) generating a foam within said mixture;
• c) depositing said foam on a moving belt to form a foamed layer without substantial drainage of said structuring composition from said layer;
• and
• d) curing said foamed layer to form an absorbent fibrous structure.

A method for producing a continuous absorbent fibrous structure comprising:

• a) forming an air-laid mat of fiberized hydrophilic fibers on a moving belt to form a fibrous mat;
• b) impregnating said mat with a foamable structuring composition comprising a substantially latex free binder material and a removable phase;
• c) rearranging said fibers in said mat through the action of said structuring composition to create a restructured layer;
• and
• (d) forming water-insoluble bonds in said restructured layer to form an absorbent fibrous structure.

A method of producing an open low-density absorbent fibrous structure comprising:

• a) combining hydrophilic fibers with a structuring composition to form a mixture, said structuring composition comprising a binder material and a removable phase;
• b) producing a foam within said mixture;
• c) removing a portion of said removable phase by one of melting or decomposition of a solid;
• and
• d) binding said fibers together with substantially water-insoluble bonds into a continuous, porous network, wherein said binder material stabilizes the porous network.

A method of producing a low-density absorbent fibrous structure comprising:

• a) combining hydrophilic fibers with a structuring composition to form a mixture, said structuring composition comprising a binder material and a removable phase;
• b) rearranging said fibers in a three-dimensional structure within said mixture;
• c) removing a portion of said removable phase, wherein said removable phase is a solid;
• and
• d) binding said fibers together into a continuous, porous network, wherein said binder material forms bonds between said fibers to stabilize said porous network.

A method of producing an open low-density absorbent fibrous structure comprising:

• a) combining hydrophilic fibers with a latex-free structuring composition to form a mixture, said structuring composition comprising a binder material and a removable phase;
• b) producing a foam within said mixture;
• and
• c) binding said fibers together with substantially water-insoluble bonds into a continuous, porous network, wherein said binder material stabilizes the porous network.

A method of producing a low-density absorbent fibrous structure comprising:

• a) combining hydrophilic fibers with a latex-free structuring composition to form a mixture, said structuring composition comprising a binder material and a removable phase;
• b) rearranging said fibers in a three-dimensional structure within said mixture;
• c) removing a portion of said removable phase;
• and
• d) binding said fibers together into a continuous, porous network, wherein said binder material forms bonds between said fibers to stabilize said porous network.

A method of producing an open low-density absorbent fibrous structure having a density of about 0.05 g/cc or less comprising:

• e) combining hydrophilic fibers with a substantially latex-free structuring composition to form a mixture, said structuring composition comprising a binder material and a removable phase;
• f) producing a foam within said mixture;
• and
• g) binding said fibers together with substantially water-insoluble bonds into a continuous, porous network, wherein said binder material stabilizes the porous network.

A method of producing an open low-density absorbent fibrous structure comprising:

• a) combining hydrophilic fibers with a structuring composition to form a mixture, the hydrophilic fibers having a consistency of either about 4% or less or greater than 30%;
• said structuring composition comprising a binder material and a removable phase;
• b) producing a foam within said mixture;
• and
• c) binding said fibers together with substantially water-insoluble bonds into a continuous, porous network, wherein said binder material stabilizes the porous network.

A method for producing a continuous absorbent fibrous structure comprising:

• a) combining dry hydrophilic fibers with a structuring composition comprising a binder material and a removable phase to form a mixture;
• b) generating a foam within said mixture;
• c) depositing said foam on a moving belt to form a foamed layer without substantial drainage of said structuring composition from said layer;
• and
• d) curing said foamed layer to form an absorbent fibrous structure.

A method of producing a low-density absorbent fibrous structure comprising:

• a) combining hydrophilic fibers having a consistency greater than about 30% with a structuring composition to form a mixture, said structuring composition comprising a binder material and a removable phase comprising a blowing agent;
• b) rearranging said fibers in a three-dimensional structure within said mixture;
• c) removing a portion of said removable phase;
• and
• d) binding said fibers together into a continuous, porous network, wherein said binder material forms bonds between said fibers to stabilize said porous network.

A method for producing a continuous absorbent fibrous structure comprising:

• (a) forming an air-laid mat of fiberized hydrophilic fibers on a moving belt to form a fibrous mat;
• (b) impregnating said mat with a foamable structuring composition comprising a substantially latex free binder material and a removable phase, wherein the impregnated mat prior to forming water insoluble bonds has a consistency of 30% or greater;
• (c) rearranging said fibers in said mat through the action of said structuring composition to create a restructured layer;
• and
• (d) forming water-insoluble bonds in said restructured layer to form an absorbent fibrous structure.