Patent US4967211A successfully refreshed from Google Patents.
Patent US4981591A successfully refreshed from Google Patents.
US4981591A
Expired / Lapsed
US
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Cationic charge modified filter media
Assignee: 3M Purification Inc
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Filing: 1989-04-07
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Granted: 1991-01-01
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Expires: 2009-04-07
Abstract
Abstract The media comprises cellulosic fiber and silica based particulate or fiber filter elements and a charge modifying amount of a cationic charge modifying system bonded to the surfaces thereof. A component of the charge modifying system is a primary charge modifying agent characterized as a water soluble organic polymer capable of being adsorbed into the filter elements and having a molecular weight greater than about 1000. Each monomer of the polymer can have at least one epoxide group capable of bonding to the surface of the filter elements and at least one quaternary ammonium group. Preferably, the primary charge modifying agent is a polyamido-polyamine epichlorohydrin resin, a polyamine epichlorohydrin resin, or a resin based upon diallylnitrogen-containing materials reacted with epichlorohydrin. A portion of the epoxy groups on the organic polymer are bonded to the secondary charge modifying agent. This secondary charge modifying agent is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Inventors
- 👤 Eugene A. Ostreicher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:29
CPC Classifications
D; D21; D21H; D21H27/00; D21H27/08; B; B01; B01D; B01D39/00; B01D39/14; B01D39/16; B01D39/18
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
128 words
A filter media comprising filter elements of cellulose fiber and silica based particulate or fiber and a charge modifying amount of a cationic charge modifying system bonded to surfaces of the elements, the system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements and having a molecular weight of greater than about 1000, each monomer of the polymer having at least one epoxide group capable of bonding to the surfaces of the elements and quaternary ammonium groups; and a secondary charge modifying agent bonded to a portion of the epoxy groups on the organic polymer, wherein said secondary charge modifying agent is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 2
Dependent Claim
128 words
A filter media comprising filter elements of cellulose fiber and silica based particulate or fiber and a charge modifying amount of a cationic charge modifying system bonded to surfaces of the elements, the system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements and having a molecular weight of greater than about 1000, each monomer of the polymer having at least one epoxide group capable of bonding to the surfaces of the elements and quaternary ammonium groups; and a secondary charge modifying agent bonded to a portion of the epoxy groups on the organic polymer, wherein said secondary charge modifying agent is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 3
Dependent Claim
18 words
The filter media of claim 1, comprising a filter sheet of cellulosic fibrous elements and particulate filter elements.
Claim 4
Dependent Claim
43 words
The filter media of claim 1, wherein the secondary charge modifying agent has the formula: H.sub.2 N--(R.sub.1 --NH--).sub.x --R.sub.2 --NH.sub.2 wherein R 1 and R 2 are alkyl of 1 to 4 carbon atoms and x is an integer from 0 to 4.
Claim 5
Dependent Claim
15 words
The filter media of claim 3, wherein R 1 and R 2 are both ethyl.
Claim 6
Dependent Claim
21 words
The filter media of claim 1, wherein the polyamine is selected from ethylene diamine, diethylene triamine, triethylene tetramine and tetraethylene pentamine.
Claim 7
Dependent Claim
12 words
The filter media of claim 1, wherein the polyamine is tetraethylene pentamine.
Claim 8
Dependent Claim
19 words
The filter media of claim 1, comprising filter elements of particulate immobilized in a porous matrix of cellulose fibers.
Claim 9
Dependent Claim
14 words
The filter media of claim 7, wherein the cellulose fibers are highly purified alpha-cellulose.
Claim 10
Dependent Claim
16 words
The filter media of claim 7, comprising at least 50% by weight of particulate filter elements.
Claim 11
Dependent Claim
24 words
The filter media of claim 9, wherein the particulate filter elements are selected from the group consisting of diatomaceous earth, perlite and mixtures thereof.
Claim 12
Dependent Claim
129 words
A filter media comprising filter elements of cellulose fiber and silica based particulate or fiber and a charge modifying amount of a cationic charge modifying system bonded to surfaces of the elements, the system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements and having a molecular weight of greater than about 1000, wherein the organic polymer is a polyamido-polyamine epichlorohydrin resin, having epoxide groups capable of bonding to the surfaces of the elements and quaternary ammonium groups; and a secondary charge modifying agent bonded to a portion of the epoxy groups on the organic polymer, wherein said secondary charge modifying agent is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 13
Dependent Claim
129 words
A filter media comprising filter elements of cellulose fiber and silica based particulate or fiber and a charge modifying amount of a cationic charge modifying system bonded to surfaces of the elements, the system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements and having a molecular weight of greater than about 1000, wherein the organic polymer is a polyamido-polyamine epichlorohydrin resin, having epoxide groups capable of bonding to the surfaces of the elements and quaternary ammonium groups; and a secondary charge modifying agent bonded to a portion of the epoxy groups on the organic polymer, wherein said secondary charge modifying agent is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 14
Dependent Claim
129 words
A filter media comprising filter elements of cellulose fiber and silica based particulate or fiber and a charge modifying amount of a cationic charge modifying system bonded to surfaces of the elements, the system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements and having a molecular weight of greater than about 1000, wherein the organic polymer is a polyamine epichlorohydrin resin, having epoxide groups capable of bonding to the surfaces of the elements and quaternary ammonium groups; and a secondary charge modifying agent bonded to a portion of the epoxy groups on the organic polymer, wherein said secondary charge modifying agent is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 15
Dependent Claim
129 words
A filter media comprising filter elements of cellulose fiber and silica based particulate or fiber and a charge modifying amount of a cationic charge modifying system bonded to surfaces of the elements, the system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements and having a molecular weight of greater than about 1000, wherein the organic polymer is a polyamine epichlorohydrin resin, having epoxide groups capable of bonding to the surfaces of the elements and quaternary ammonium groups; and a secondary charge modifying agent bonded to a portion of the epoxy groups on the organic polymer, wherein said secondary charge modifying agent is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 16
Dependent Claim
134 words
A filter media comprising filter elements of cellulose fiber and silica based particulate or fiber and a charge modifying amount of a cationic charge modifying system bonded to surfaces of the elements, the system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements and having a molecular weight of greater than about 1000, wherein the organic polymer is a resin based upon diallylnitrogen-containing materials reacted with epichlorohydrin, having epoxide groups capable of bonding to the surfaces of the elements and quaternary ammonium groups; and a secondary charge modifying agent bonded to a portion of the epoxy groups on the organic polymer, wherein said secondary charge modifying agent is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 17
Dependent Claim
134 words
A filter media comprising filter elements of cellulose fiber and silica based particulate or fiber and a charge modifying amount of a cationic charge modifying system bonded to surfaces of the elements, the system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements and having a molecular weight of greater than about 1000, wherein the organic polymer is a resin based upon diallylnitrogen-containing materials reacted with epichlorohydrin, having epoxide groups capable of bonding to the surfaces of the elements and quaternary ammonium groups; and a secondary charge modifying agent bonded to a portion of the epoxy groups on the organic polymer, wherein said secondary charge modifying agent is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 18
Dependent Claim
142 words
A filter media comprising filter elements of cellulose fiber and silica based particulate or fiber and a charge modifying amount of a cationic charge modifying system bonded to surfaces of the elements, the system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements and having a molecular weight of greater than about 1000, wherein the organic polymer is the reaction product of a polyamine with epichlorohydrin, said product having along the polyamine chain (i) quaternary ammonium groups, and (ii) epoxide groups capable of bonding to the surface of the filter elements and a secondary charge modifying agent bonded to a portion of the epoxy groups on the organic polymer, wherein said secondary charge modifying agent is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 19
Dependent Claim
142 words
A filter media comprising filter elements of cellulose fiber and silica based particulate or fiber and a charge modifying amount of a cationic charge modifying system bonded to surfaces of the elements, the system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements and having a molecular weight of greater than about 1000, wherein the organic polymer is the reaction product of a polyamine with epichlorohydrin, said product having along the polyamine chain (i) quaternary ammonium groups, and (ii) epoxide groups capable of bonding to the surface of the filter elements and a secondary charge modifying agent bonded to a portion of the epoxy groups on the organic polymer, wherein said secondary charge modifying agent is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 20
Dependent Claim
107 words
A process for preparing a charge modified filter media comprising filter elements of cellulosic fiber and silica based particulate or fiber comprising: applying to the filter elements a charge modifying system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements and having a molecular weight of greater than about 1000, each monomer of the polymer having at least one epoxide group capable of bonding to surfaces of the elements and quaternary ammonium groups; and a secondary charge modifying agent which is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 21
Dependent Claim
107 words
A process for preparing a charge modified filter media comprising filter elements of cellulosic fiber and silica based particulate or fiber comprising: applying to the filter elements a charge modifying system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements and having a molecular weight of greater than about 1000, each monomer of the polymer having at least one epoxide group capable of bonding to surfaces of the elements and quaternary ammonium groups; and a secondary charge modifying agent which is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 22
Dependent Claim
38 words
The process of claim 15, comprising (a) contacting the filter elements with an aqueous solution of the primary cationic charge modifying agent and (b) contacting the filter elements with an aqueous solution of the secondary charge modifying agent.
Claim 23
Dependent Claim
12 words
The process of claim 16, wherein the contacting steps are performed simultaneously.
Claim 24
Dependent Claim
40 words
The process of claim 17, wherein the contacting steps are performed by contacting the filter elements with an aqueous solution of a mixture of the primary charge modifying agent and the secondary charge modifying agent to form an aqueous composition.
Claim 25
Dependent Claim
14 words
The process of claim 18, further comprising vacuum felting and drying the aqueous composition.
Claim 26
Dependent Claim
29 words
The process of claim 16, wherein the aqueous solution of primary charge modifying agent is at least about 1% primary charge modifying agent by weight of the filter elements.
Claim 27
Dependent Claim
29 words
The process of claim 20, wherein the aqueous solution of primary charge modifying agent does not exceed about 5% primary charge modifying agent by weight of the filter elements.
Claim 28
Dependent Claim
36 words
The process of claim 16, wherein the secondary charge modifying agent is present in amount sufficient to form a ratio of primary to secondary charge modifying agent of from about 1:1 to about 10:1, by weight.
Claim 29
Dependent Claim
16 words
The process of claim 22, wherein the ratio is about 3:1 to about 6:1, by weight.
Claim 30
Dependent Claim
30 words
The process of claim 16, wherein the aqueous solution of secondary charge modifying agent contains about 0.2% to about 0.5% secondary charge modifying agent by weight of the filter elements.
Claim 31
Dependent Claim
14 words
The process of claim 15, wherein the secondary charge modifying agent is tetraethylene pentamine.
Claim 32
Dependent Claim
109 words
A process for preparing a charge modified filter media comprising filter elements of cellulosic fiber and silica based particulate or fiber comprising: applying to the filter elements a charge modifying system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements and having a molecular weight of greater than about 1000, wherein the organic polymer is a polyamido-polyamine epichlorohydrin resin having epoxide groups capable of bonding to the surfaces of the elements and quaternary ammonium groups; and a secondary charge modifying agent which is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 33
Dependent Claim
109 words
A process for preparing a charge modified filter media comprising filter elements of cellulosic fiber and silica based particulate or fiber comprising: applying to the filter elements a charge modifying system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements and having a molecular weight of greater than about 1000, wherein the organic polymer is a polyamido-polyamine epichlorohydrin resin having epoxide groups capable of bonding to the surfaces of the elements and quaternary ammonium groups; and a secondary charge modifying agent which is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 34
Dependent Claim
109 words
A process for preparing a charge modified filter media comprising filter elements of cellulosic fiber and silica based particulate or fiber comprising: applying to the filter elements a charge modifying system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements and having a molecular weight of greater than about 1000, wherein the organic polymer is a polyamine epichlorohydrin resin, having epoxide groups capable of bonding to the surfaces of the elements and quaternary ammonium groups; and a secondary charge modifying agent which is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 35
Dependent Claim
109 words
A process for preparing a charge modified filter media comprising filter elements of cellulosic fiber and silica based particulate or fiber comprising: applying to the filter elements a charge modifying system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements and having a molecular weight of greater than about 1000, wherein the organic polymer is a polyamine epichlorohydrin resin, having epoxide groups capable of bonding to the surfaces of the elements and quaternary ammonium groups; and a secondary charge modifying agent which is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 36
Dependent Claim
113 words
A process for preparing a charge modified filter media comprising filter elements of cellulosic fiber and silica based particulate or fiber comprising: applying to the filter elements a charge modifying system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements having a molecular weight of greater than about 1000, wherein the organic polymer is a resin based upon diallylnitrogen-containing materials reacted with epichlorohydrin, having epoxide groups capable of bonding to the surfaces of the elements and quaternary ammonium groups; and a secondary charge modifying agent which is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 37
Dependent Claim
113 words
A process for preparing a charge modified filter media comprising filter elements of cellulosic fiber and silica based particulate or fiber comprising: applying to the filter elements a charge modifying system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements having a molecular weight of greater than about 1000, wherein the organic polymer is a resin based upon diallylnitrogen-containing materials reacted with epichlorohydrin, having epoxide groups capable of bonding to the surfaces of the elements and quaternary ammonium groups; and a secondary charge modifying agent which is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 38
Dependent Claim
120 words
A process for preparing a charge modified filter media comprising filter elements of cellulosic fiber and silica based particulate or fiber comprising: applying to the filter elements a charge modifying system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements having a molecular weight of greater than about 1000, wherein the resin is a reaction product of a polyamine with epichlorohydrin, said product having along the polyamine chain (i) quaternary ammonium groups, and (ii) epoxide groups capable of bonding to the surfaces of the filter elements and a secondary charge modifying agent which is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
Claim 39
Dependent Claim
120 words
A process for preparing a charge modified filter media comprising filter elements of cellulosic fiber and silica based particulate or fiber comprising: applying to the filter elements a charge modifying system comprising: a primary charge modifying agent which is a water soluble organic polymer capable of being adsorbed onto the elements having a molecular weight of greater than about 1000, wherein the resin is a reaction product of a polyamine with epichlorohydrin, said product having along the polyamine chain (i) quaternary ammonium groups, and (ii) epoxide groups capable of bonding to the surfaces of the filter elements and a secondary charge modifying agent which is an aliphatic polyamine having at least one primary amine or at least two secondary amines.
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| 3.5 Years (Year 4) | 1993-12-31 | 1994-07-02 | 1995-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-31 | 1998-07-02 | 1999-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-31 | 2002-07-02 | 2003-01-01 | $7700.00 | Window Closed / Lapsed |