Process for producing heatsealable filter materials

1. A process for producing a filter material comprising producing a filter material by a wet-laid process wherein the filter material comprises a plurality of first fibers and a plurality of second fibers, wherein the plurality of second fibers comprises a heatsealable, biodegradable and compostable material and wherein the heatsealable, biodegradable and compostable material is combined with a lubricant in an amount from 0.5 to 5.0% by weight, based on paper weight of a ready-produced filter material.

2. A process for producing a filter material according to claim 1 , wherein the plurality of second fibers consists essentially of the heatsealable, biodegradable and compostable material.

3. A process for producing a filter material by a wet-laid process comprising:

(a) forming a first suspension of a plurality of first fibers in water, wherein the plurality of first fibers comprises natural fibers;

(b) forming a second suspension of a plurality of second fibers in water with a lubricant in an amount to achieve a concentration of lubricant of from 0.5 to 5.0% by weight based on paper weight of a produced filter material, wherein the plurality of second fibers comprises a heatsealable, biodegradable and compostable material;

(c) forming a first fibrous layer by depositing the first suspension onto a circulating screen traveling across at least one dewatering chamber; and

(d) forming a second fibrous layer by depositing the second suspension on top of the first fibrous layer traveling along the circulating screen and across the at least one dewatering chamber.

4. A process for producing a filter material according to claim 3 , wherein the first fibrous layer begins dewatering before the second suspension is deposited on top of the first fibrous layer.

5. A process for producing a filter material according to claim 3 , further comprising:

(e) dewatering the first and second fibrous layers causing at least a partial interpenetration of the first and second fibrous layers.

6. A process for producing a filter material according to claim 5 , wherein the dewatering step comprises adjusting the degree of dewatering to control the degree of interpenetration.

7. A process for producing a filter material according to claim 5 , further comprising:

(f) drying the first and second fibrous layers to form a filter material.

8. A process for producing a filter material according to claim 7 , wherein the drying step is performed by contact drying.

9. A process for producing a filter material according to claim 7 , wherein the drying step is performed by flowthrough drying.

10. A process for producing a filter material according to claim 7 , wherein the drying step causes the plurality of second fibers to melt; and subsequent to the drying step the melted fibers resolidify resulting in the second fibers at least partially encasing the first fibers.

11. A process for producing a filter material according to claim 7 , further comprising:

(g) forming the dryed filter material into tea bags, coffee bags, tea filters, or coffee filters.

12. A process for producing a filter material according to claim 5 , further comprising:

(f) heating the first and second fibrous layers, wherein the heating causes the plurality of second fibers to melt; and subsequent to heating the melted fibers resolidify resulting in the second fibers at least partially encasing the first fibers.

13. A process for producing a filter material according to claim 3 , wherein the natural fibers are selected from the group consisting of hemp, manila, jute, sisal, and combinations thereof.

14. A process for producing a filter material according to claim 3 , wherein the natural fibers are a blend of manila and softwood pulp.

15. A process for producing a filter material according to claim 14 , wherein the filter material is arranged as a tea filter, a coffee filter, a tea bag, or a coffee bag.

16. A process for producing a filter material according to claim 3 , wherein the plurality of second fibers consists essentially of the heatsealable, biodegradable and compostable material.