EP0094165A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Resin inpregnated filter papers
Assignee: Hexion UK Ltd
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Filing: 1983-04-22
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Granted: —
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Expires: 2003-04-22
Abstract
Abstract Filter papers, such as those used in vehicle oil and air filters, may be made by impregnating a filter paper with an alkaline phenol-aldehyde resin, contacting with an ester, as curing catalyst, and curing the resin. The resin used will have an aldehyde to phenol molar ratio of from 1:1 to 3.5:1, an alkali to phenol molar ratio of from 0.1:1 to 1.5:1 and a weight average molecular weight of from 200 to 4000.
Inventors
- 👤 Peter Herbert Richard Bryan Lemon
- 👤 John Richard Swire
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 21:27
CPC Classifications
D; D21; D21H; D21H17/00; D21H17/20; D21H17/33; D21H17/46; D21H17/47; D21H17/48; B; B01; B01D; B01D39/00; B01D39/14; B01D39/16; B01D39/18; C; C08; C08G; C08G8/00; C08G8/04; C08K; C08K5/00; C08K5/04; C08K5/10
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
92 words
A method of making a resin impregnated paper filter which comprises providing a filter paper impregnated with an alkaline phenol-aldehyde resin, which resin has the following properties:- a) an aldehyde to phenol molar ratio of from 1:1 to 3.5:1; b) an alkali to phenol molar ratio of from 0.1:1 to 1.5:1; and c) a weight average molecular weight of from 200 to 4000; contacting the resin with an ester, as catalyst,for curing the resin and, before, during or after curing the resin, forming the paper into the desired shape for the filter.
Claim 2
Independent Claim
92 words
A method of making a resin impregnated paper filter which comprises providing a filter paper impregnated with an alkaline phenol-aldehyde resin, which resin has the following properties:- a) an aldehyde to phenol molar ratio of from 1:1 to 3.5:1; b) an alkali to phenol molar ratio of from 0.1:1 to 1.5:1; and c) a weight average molecular weight of from 200 to 4000; contacting the resin with an ester, as catalyst,for curing the resin and, before, during or after curing the resin, forming the paper into the desired shape for the filter.
Claim 3
Independent Claim
83 words
A method of making a pleatable blank for a resin impregnated paper filter which comprises providing a filter paper impregnated with an alkaline phenol-aldehyde resin, which resin has the following properties:- a) an aldehyde to phenol molar ratio of from 1:1 to 3.5:1; b) an alkali to phenol molar ratio of from 0.1:1 to 1.5:1; and c) a weight average molecular weight of from 200 to 4000; contacting the resin with an ester, as catalyst, for curing the resin and curing the resin.
Claim 4
Independent Claim
83 words
A method of making a pleatable blank for a resin impregnated paper filter which comprises providing a filter paper impregnated with an alkaline phenol-aldehyde resin, which resin has the following properties:- a) an aldehyde to phenol molar ratio of from 1:1 to 3.5:1; b) an alkali to phenol molar ratio of from 0.1:1 to 1.5:1; and c) a weight average molecular weight of from 200 to 4000; contacting the resin with an ester, as catalyst, for curing the resin and curing the resin.
Claim 5
Dependent Claim
45 words
The method according to either claim 1 or claim 2, wherein the phenol component of the alkaline- phenol-aldehyde resin is selected from phenol, cresoles, xylenols, ethyl phenols and substituted phenols obtained from fractionation of coal tar and from cashew nut shell liquid, and mixtures thereof.
Claim 6
Dependent Claim
18 words
The method according to claim 3, wherein the phenol component of the alkaline phenol-aldehyde resin is phenol itself.
Claim 7
Independent Claim
30 words
The method according to any one of claims 1 to 4, wherein the aldehyde component of the alkaline phenol-aldehyde resin is selected from formaldehyde, acetaldehyde, butyraldehyde, furfuraldehde and mixtures thereof.
Claim 8
Dependent Claim
17 words
The method according to claim 5, wherein the aldehyde component of the alkaline phenol-aldehyde resin is formaldehyde.
Claim 9
Independent Claim
27 words
The method according to any one of claims 1 to 6, wherein the alkaline phenol-aldehyde resin has a weight average molecular weight of from 400 to 2000.
Claim 10
Dependent Claim
29 words
. The method according to any one of claims 1 to .7, wherein the alkaline phenol-aldehyde resin has an alkali to phenol molar ratio of from 0.4:1 to 1.1:1.
Claim 11
Independent Claim
28 words
The method according to any one of claims 1 to 8, wherein the alkaline phenol-aldehyde resin has an aldehyde to phenol molar ratio of from 1.2:1 to 2.5:1.
Claim 12
Dependent Claim
61 words
The method according to either claim 1 or claim 2, wherein the alkaline phenol-aldehyde resin is an alkaline phenol-formaldehyde resin having a weight average molecular weight of from 400 to 2000, an alkali to phenol molar ratio of from 0.4:1 to 1.1:1, the alkali being sodium and/or potassium hydroxide, and a formaldehyde to phenol molar ratio of from 1.2:1 to 2.5:1.
Claim 13
Independent Claim
43 words
The method according to any one of claims 1 to 10, wherein the ester is selected from methyl formate, ethyl formate, propyl formate, methyl acetate, ethyl acetate, ethylene glycol diacetate, triacetin, butyrolactone, caprolactone, valerolactone, ethylene carbonate, propylene carbonate, dimethyl carbonate and mixtures thereof.
Claim 14
Independent Claim
35 words
The method according to any one of claims 1 to 11, wherein the ester is used in an amount of from 10 to 50% by weight based on the organic solids content of the resin.
Claim 15
Dependent Claim
30 words
The method according to claim 12, wherein the ester is used in an amount of from 15 to 40% by weight based on the organic solids content of the resin.
References Cited (Backward Citations)
No citation records indexed.
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