	US 12,460,352 B2
	Filter paper for cigarette filters and filter comprising it
Agustín Tosas Fuentes, Barcelona (ES); Mónica Ferreró Aragonés, Barcelona (ES); Marcel Alemany Munné, Barcelona (ES); and Pablo De Mariscal Ruigómez, Barcelona (ES)
Assigned to MIQUEL Y COSTAS & MIQUEL, S.A., Barcelona (ES)
Filed by MIQUEL Y COSTAS & MIQUEL, S.A., Barcelona (ES)
Filed on Jul. 18, 2023, as Appl. No. 18/223,104.
Claims priority of application No. ES202230664 (ES), filed on Jul. 19, 2022.
Prior Publication US 2024/0026609 A1, Jan. 25, 2024
Int. Cl. D21H 15/06 (2006.01); A24D 3/06 (2006.01); A24D 3/10 (2006.01); D21H 17/26 (2006.01); D21H 27/08 (2006.01)

CPC D21H 15/06 (2013.01) [A24D 3/063 (2013.01); A24D 3/10 (2013.01); D21H 17/26 (2013.01); D21H 27/08 (2013.01)]

3 Claims

1. A filter paper comprising:

a) between 70% and 100% by weight of cellulose fibers, wherein between 50% and 75% by weight of the fibers are long fibers, understanding by long fibers those having an average length greater than 2 mm, and wherein between 25% and 50% by weight of the fibers are short fibers, understanding by short fibers those having an average length of less than 2 mm; and

b) between 0.1% and 5.0% by weight of sodium carboxymethyl cellulose,

and wherein:

c) the weight of the filter paper per unit area is between 25 and 55 g/m², measured according to UNE-EN ISO 536:2013 standard;

d) the density of the filter paper, measured according to UNE-EN ISO 534:2012 standard in a single sheet, varies between 0.100 and 0.500 g/cm³; and

e) the porosity filter paper is comprised between 1500 and 8500 ml/min·cm²·kPa, measured according to UNE-EN ISO 2965:2019 standard.