US 5,496,573 AGranted

Coffee filter material and coffee filter bag

AssigneesYamanaka Industry Co., Ltd., Kuraray Co., Ltd.

InventorsHiroshi Tsuji, Hiromasa Saisaka, Hideo Murakami, Kaichi Suzuki, Masaaki Fukuchi

Life of this patent

Estimating the term…

Loading patent…

Abstract

A coffee filter material and bag suitable for providing a high-quality coffee extract, having a nonwoven fabric filter layer which is composed of thermoplastic organic synthetic fibers, satisfies the relationships (1) to (4): 3.ltoreq.x.ltoreq.30 (1) y.gtoreq.0.2x (2) 1.ltoreq.r.sub.30 (3) and r.sub.70 .ltoreq.50 (4) wherein x is a basis weight (g/m.sup.2) of the woven fabric, y is a cumulative volume value (cm.sup.3 /g) of fine pores in the nonwoven fabric, r.sub.30 is a maximum radius (.mu.m) of the fine pores observed when the volumes of the fine pores are cumulated from the small pore radius side and the cumulative volume value becomes equal to 0.3y, and r.sub.70 is a maximum radium (.mu.m) of the fine pores observed when the volumes of the fine pores are cumulated from the small pore radius side and the cumulative volume value becomes equal to 0.7y, and is capable of absorbing in the wet state thereof at least 0.5 g/g of an oil and fat component from the coffee extract.

Claims6

Dependent claims

A coffee filter bag formed from a coffee filter material having a fibrous filter layer comprising a filter nonwoven fabric having pores, said pores varying in volume in accordance with the radius of the pores, said fabric being composed of melt blown polypropylene fibers having an average diameter of 15 .mu.m or less, wherein the filter nonwoven fabric satisfies the relationships (1) to (4):

3.ltoreq.x.ltoreq.30 (1),
y.gtoreq.0.2x (2),
3.ltoreq.r.sub.30 ( 3),
and
r.sub.70 .ltoreq.40 (4)
wherein x represents a basis weight (g/m.sup.2) of the filter nonwoven fabric, y represents a cumulative volume value (cm.sup.3 /g) of said pores in the filter nonwoven fabric, determined by a mercury porosimeter in which mercury is forced into the filter nonwoven fabric and the amount of mercury penetrated into the fabric is measured while changing the forcing pressure of mercury in the range of 0.4 to 10,000 PSI, r.sub.30 represents a maximum radius (.mu.m) of the pores observed when the volume of the pores in the filter nonwoven fabric are cumulated by said porosimeter starting with the volumes of said pores having a smallest radius and the cumulative volume value becomes equal to 0.3y, and r.sub.70 represents a maximum radius (.mu.m) of the pores observed when the volumes of the pores in the filter nonwoven fabric are cumulated by said porosimeter starting with the volume of said pores having a smallest radius and the cumulative volume becomes equal to 0.7y, and is capable of removing from a mixture of 400 ml of distilled water and 1.0 gram of an oil and fat component extracted from coffee at least 0.5 gram of said oil and fat component per gram of fiber when the filter nonwoven fabric having an area of 100 cm.sup.2 is boiled for 5 minutes in said mixture and a supporting layer comprising at least one sheet of a reinforcing fabric having no substantial influence on the filtering property of the fibrous filter layer and laminated and combined with the fibrous filter layer to form an integrated composite sheet material.

3 more elements

A method of extracting coffee comprising placing a coffee filter bag containing a coffee powder in a cup, and pouring hot water onto the coffee filter bag, in which the coffee filter bag is formed from a coffee filter material having a fibrous filter layer comprising a filter nonwoven fabric having pores, said pores varying in volume in accordance with the radius thereof, said fabric being composed of melt blown polypropylene fibers having an average diameter of 15 .mu.m or less, wherein the filter nonwoven fabric satisfies the relationships (1) to (4):

3.ltoreq.x.ltoreq.30 (1),
y.gtoreq.0.2x (2),
3.ltoreq.r.sub.30 ( 3),
and
r.sub.70 40 (4)
wherein x represents a basis weight (g/m.sup.2) of the filter nonwoven fabric, y represents a cumulative volume value (cm.sup.3 /gl of said pores in the filter nonwoven fabric, determined by a mercury porosimeter in which mercury is forced into the filter nonwoven fabric and the amount of mercury penetrated into the fabric is measured while changing the forcing pressure of mercury in the range of 0.4 to 10,000 PSI, r.sub.30 represents a maximum radius (.mu.m) of the pores in the filter nonwoven fabric are cumulated by said porosimeter starting with the volumes of said pores having a smallest radius and the cumulative volume value becomes equal to 0.3y, and, r.sub.70 represents a maximum radius (.mu.m) of the pores observed when the volumes of the pores in the filter nonwoven fabric are cumulated by said porosimeter starting with the volume of said pores having a smallest radius and the cumulative volume value becomes equal to 0.7, and is capable of removing from a mixture of 400 ml of distilled water and 1.0 gram of an oil and fat component extracted from coffee at least 0.5 gram of said oil and fat component per gram of fiber when the filter nonwoven fabric having an area of 100 cm.sup.2 is boiled for 5 minutes in said mixture.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application: 08/395,174Filed 27 Feb 1995 · continuation
Priority: JP 1-1980011 Aug 1989
Granted: 5 Mar 1996
Term ends: Not estimatedThe source records don’t support an estimate.

Classification4 codes

A47J 31/08
Filters or strainers for coffee or tea makers ; Holders therefor: paper filter inlays therefor to be disposed after use
B01D 39/163
Of synthetic origin: sintered or bonded
A47J
Kitchen equipment
B01D
Separation