Filter and method of making same

• US 5,338,340 A
• Filed: 06/30/1993
• Issued: 08/16/1994
• Est. Priority Date: 02/10/1990
• Status: Expired due to Fees

• Current Assignee: D-Mark Inc.
• Original Assignee: D-Mark Inc.
• Inventors: Kasmark, James W. Jr., Brown, deceased, Joseph B.
• Primary Examiner(s): Hart, Charles
• Application Number:
  US08/086,187
• Time in Patent Office: 412 Days
• Field of Search: 55/486, 55/524, 55/528, 55/DIG. 42, 96/134, 96/135, 96/132, 96/137
• US Class Current: 96/135
• CPC Class Codes: B01D 2239/045 Deodorising additives
• CPC Class Codes: B01D 2239/0478 on a layer of the filter
• CPC Class Codes: B01D 2239/0492 on fibres
• CPC Class Codes: B01D 2239/0609 Knitted
• CPC Class Codes: B01D 2239/0613 Woven
• CPC Class Codes: B01D 2239/0627 Spun-bonded
• CPC Class Codes: B01D 2239/065 More than one layer present in the filtering material
• CPC Class Codes: B01D 2239/0654 Support layers
• CPC Class Codes: B01D 2239/086 Binders between particles or fibres
• CPC Class Codes: B01D 2239/10 Filtering material manufacturing
• CPC Class Codes: B01D 2239/1233 Fibre diameter
• CPC Class Codes: B01D 2239/1241 Particle diameter
• CPC Class Codes: B01D 2251/306 of potassium
• CPC Class Codes: B01D 2251/60 Inorganic bases or salts
• CPC Class Codes: B01D 2253/102 Carbon
• CPC Class Codes: B01D 2253/104 Alumina
• CPC Class Codes: B01D 2253/25 Coated, impregnated or composite adsorbents
• CPC Class Codes: B01D 2257/406 Ammonia
• CPC Class Codes: B01D 2257/90 Odorous compounds not provided for in groups B01D2257/00 - B01D2257/708
• CPC Class Codes: B01D 39/1623 of synthetic origin
• CPC Class Codes: B01D 39/1676 : of synthetic origin
• CPC Class Codes: B01D 39/2017 : the material being filamentary or fibrous
• CPC Class Codes: B01D 39/2062 : Bonded, e.g. activated carbon blocks
• CPC Class Codes: B01D 53/02 : by adsorption, e.g. preparative gas chromatography solid sorbent compositions B01J20/00, preparation of inorganic compounds or elements C01
• CPC Class Codes: B01D 53/0454 : Controlling adsorption controlling temperature swing adsorption B01D53/0462, controlling pressure swing adsorption B01D53/047
• CPC Class Codes: B01J 20/28004 : Sorbent size or size distribution, e.g. particle size
• CPC Class Codes: B01J 20/28011 : Other properties, e.g. density, crush strength
• CPC Class Codes: B01J 20/28028 : Particles immobilised within fibres or filaments
• CPC Class Codes: B01J 20/28033 : Membrane, sheet, cloth, pad, lamellar or mat
• CPC Class Codes: B01J 20/28045 : Honeycomb or cellular structures; Solid foams or sponges
• CPC Class Codes: B01J 20/28097 : being coated, filled or plugged with specific compounds
• CPC Class Codes: Y10S 55/42 : Foam filter materials

Abstract

An odor-removing filter approaching the carbon-particle loading of a filled filter may be formed by spraying or roll coating the adhesive against one or more faces of a porous, fibrous, air-permeable mat, depositing carbon particles or other odor-removing particles of a size to compliment the void size of the mat on the adhesive coated face or faces of the mat and then driving the particles into the mat and thereafter curing the adhesive to lock the particles into the mat. The adhesive bond of the particles to the mat is improved by working the particles against the adhesive-coated fibers. An overspray of an adhesive may also be utilized to further improve the retention of the particles. So-called "clean filters" may be produced according to the method disclosed, wherein a white, fibrous mat has carbon particles loaded on one face while the opposite face appears white or "clean". An indicator filter notifying the user when the filter becomes grease laden may also be formed following the methods used herein.

Claims

1. An odor and grease or oil removing filter comprising:

a light colored, air-permeable, porous substrate for entrapping oil or grease aerosols and having opposed faces;

a layer of particulate activated carbon distributed throughout one face of the substrate and extending into the substrate but essentially invisible from the opposite face and adhesively secured to the substrate, whereby one face of the substrate is a black color and the other face is a light color to exhibit accumulating oil or grease aerosols.

2. The invention defined by claim 1 wherein the layer of particulate activated carbon extends through between approximately 1/4 and 1/2 the thickness of the substrate.

3. The invention defined by claim 1 wherein the substrate is a non-woven fabric.

4. An odor-removing substrate comprising, in combination:

a porous, air-permeable mat having voids therein;

an odor-removing particulate media distributed substantially uniformly throughout at least a portion of the mat with the particulate media being of such size in relation to the size of the voids that the particles substantially fill the voids of the mat;

an adhesive bonding the odor-removing particles in the voids in the mat; and

said particulate media being present in an amount equal to at least 8.8% by volume of the mat.

5. The odor removing substrate of claim 4 wherein

the air-permeable mat is a sheet like substrate for entrapping grease or oil aerosols and having opposed faces through which air flows, the odor removing substrate further comprising:

a grease or oil soluble coating on only one of the faces and which is of a color different than that of the mat and is invisible or essentially invisible from the other opposed face; and

wherein the odor removing particulate media is a layer distributed throughout said one face of the mat and is invisible or essentially invisible from the other opposed face and is adhesively secured to the mat.

6. The invention defined by claim 5 wherein the layer of odor removing particulate media extends into the substrate toward the other opposed face and is adhesively secured in the substrate.

7. The odor removing substrate of claim 4 wherein

the air-permeable mat is a non-woven fibrous substrate having a fiber denier lying in the range of approximately 100 to 400 with a density of from 1 to 18 ounces per square yard;

and

the odor-removing particles are distributed through said mat and adhesively secured therein with a loading lying in the range of from 8.8% to 88% by volume and a particle size of from 4/6 to 20/50 on the U.S. Screen Series.

8. An air treatment filter comprising in combination;

an air permeable non-woven fibrous substrate having a fiber denier of approximately 40;

a second substrate juxtaposing one face of the first substrate of a non-woven air permeable fibrous character and filled with air treating particulate material adhesively secured to the fibers of such substrate;

a stiffening layer juxtaposed against the opposite face of the second mentioned substrate;

a reticulated foam layer overlying the exposed face of the stiffening layer; and

an enclosing frame surrounding the assembly.

9. A filter structure comprising, in combination;

a non-woven fibrous prefilter substrate juxtaposing one face of a non-woven fibrous substrate having adhesively secured therewith air treating particulate material; and

a reticulated foam layer overlying the exposed face of the second mentioned substrate and extending along the edges thereof and secured to the prefilter.

10. An air treating filter comprising, in combination;

a fibrous non-woven substrate having on one face and extending thereinto air treating particulate material adhesively secured to the substrate; and

a reticulated foam layer overlying the face coated with the air treating particulate media and extending over the edges of the substrate and secured thereto.

11. An air treating filter comprising, in combination;

a fibrous non-woven substrate having on at least one face and extending thereinto air treating particulate material adhesively secured to the substrate;

a reticulated foam layer overlying the coated face of the substrate and extending to the edges thereof; and

an enclosing frame surrounding the edges of the substrate and foam layer.

12. The invention defined by claim 11 wherein said frame includes connecting portions bridging across opposite faces of the substrate and foam layer sandwich.

13. An air treating filter comprising, in combination;

a fibrous non-woven substrate having on at least one face and extending thereinto air treating particulate material adhesively secured to the substrate;

a stiffening layer coextensive with the substrate and disposed closely adjacent thereto; and

a reticulated foam layer overlying that face of the substrate coated with the particulate material for preventing shedding of any particulate from the filter.

14. An air treatment filter comprising in combination:

an air permeable non-woven fibrous first substrate having a fiber denier of from 3 to 200;

a second air permeable non-woven fibrous substrate juxtaposing one face of the first substrate and having a portion filled with air treating particulate material adhesively secured to the fibers of said second substrate; and

an enclosing frame surrounding the assembly.

15. The air treatment filter of claim 14 further comprising:

a stiffening layer juxtaposed against the opposite face of the second mentioned substrate.

16. The air treatment filter of claim 14 further comprising a reticulated foam layer overlying the exposed face of the stiffening layer.

17. The air treatment filter of claim 14 wherein the filter substrate is prefilter material.

18. An air treatment filter comprising in combination:

an odor-removing substrate comprising;

a porous air permeable mat having voids therein;

an odor-removing particulate media distributed substantially uniformly throughout at least a portion of the mat with the particulate media being of such size in relation to the size of the voids that the particles substantially fill the voids of the mat; and

an adhesive bonding the odor-removing particles to the fibers of the mat; and

a filter frame encompassing the odor-removing substrate.

19. The air treatment filter of claim 18 wherein the filter frame further comprises:

an air permeable expanded metal substrate juxtaposed on at least one face of the odor-removing substrate; and

a scrim material juxtaposed on at least one face of the expanded metal substrate.

20. The air treatment filter of claim 19 wherein the scrim material comprises netting.

21. An odor removing filter comprising, in combination:

an air-permeable non-woven fibrous substrate having a fiber denier in the range of about 3 to 400 and a density from about 1 to 18 ounces per square yard; and

odor-removing particles distributed through said substrate and adhesively secured therein with a loading lying in the range of from 8.8% to 88% by volume and a particle size of from 4/6 to 20/50 on the U.S. Screen Series.

22. The odor-removing filter of claim 21 further comprising an air permeable non-woven fibrous substrate having a fiber denier lying in the range of 3 to 60 denier and a density of from 2 ounces per square yard to 18 ounces per square yard.

23. The odor-removing filter of claim 21 further comprising an air permeable non-woven fibrous substrate having a fiber denier lying in the range of approximately 100 to 400 denier and having a density from 3.5 ounces per square yard to 18 ounces per square yard.