Patent US3933677A successfully refreshed from Google Patents.
US3933677A
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Preparation of aqueous dispersions of blocked aromatic polyisocyanates
Assignee: EIDP Inc
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Filing: 1974-05-24
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Granted: 1976-01-20
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Expires: 1994-05-24
Abstract
Abstract Aqueous dispersions of aromatic polyisocyanates blocked with phenolic compounds are prepared by mixing the polyisocyanate dissolved in an organic water-soluble solvent and an aqueous solution containing an excess of the phenolic compound in the presence of an alkali metal hydroxide catalyst. When the phenolic compound is resorcinol, the excess resorcinol in the dispersion may be reacted with formaldehyde to form a resorcinol-formaldehyde resin; when the phenolic compound is phenol, excess resorcinol may be added and formaldehyde reacted with it to form the resorcinol-formaldehyde resin, a polyepoxide and a rubber latex may be also dispersed thus forming a dispersion that may be used to form single dip adhesive coatings on polyester substrates which will adhere to rubber.
Inventors
- 👤 Carl Albert Aufdermarsh, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:18
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/04; C08J5/06; C08J2321/00
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
101 words
A process for the production of an aqueous dispersion of an aromatic polyisocyanate blocked with a phenolic compound which comprises mixing (a) an aromatic polyisocyanate dissolved in a water-soluble organic solvent that is nonreactive with the aromatic polyisocyanate, and (b) an aqueous solution containing a dissolved phenolic compound selected from the class consisting of phenol and resorcinol, the number of moles of the phenolic compound being at least equal to the number of equivalents of isocyanate groups present, said mixing taking place in the presence of a catalytic amount of an alkali metal hydroxide at a temperature of 25° to 75°C.
Claim 2
Dependent Claim
101 words
A process for the production of an aqueous dispersion of an aromatic polyisocyanate blocked with a phenolic compound which comprises mixing (a) an aromatic polyisocyanate dissolved in a water-soluble organic solvent that is nonreactive with the aromatic polyisocyanate, and (b) an aqueous solution containing a dissolved phenolic compound selected from the class consisting of phenol and resorcinol, the number of moles of the phenolic compound being at least equal to the number of equivalents of isocyanate groups present, said mixing taking place in the presence of a catalytic amount of an alkali metal hydroxide at a temperature of 25° to 75°C.
Claim 3
Dependent Claim
33 words
The process of claim 1 in which the mixing takes place for between 10 and 120 minutes, and the dispersion contains 1 to 25% by weight of the dispersion of blocked aromatic polyisocyanate.
Claim 4
Dependent Claim
27 words
The process of claim 1 in which the catalytic amount of alkali metal hydroxide is 0.05 to 1.0 wt. percent based on the amount of water present.
Claim 5
Dependent Claim
32 words
The process of claim 1 in which a water soluble anionic surfactant is present during the mixing in the amount of 1-10 wt. % based on the amount of blocked isocyanate prepared.
Claim 6
Dependent Claim
17 words
The process of claim 1 which comprises the additional step of removing the organic solvent by distillation.
Claim 7
Dependent Claim
23 words
The process of claim 1 in which the aromatic polyisocyanate is selected from the class consisting of diphenylmethane-4,4'-diisocyanate, toluene-2,4-diisocyanate, benzene-1,3-diisocyanate, diphenylether-2,4,4'-triisocyanate, and triphenylmethane-4,4'-4"-triisocyanate.
Claim 8
Dependent Claim
23 words
The process of claim 6 in which the organic solvent is selected from the class consisting of acetone, methyl ethyl ketone and tetrahydrofuran.
References Cited (Backward Citations)
US3268467A
Cited
US3226276A
Cited
US3234067A
Cited
US3278333A
Cited
US3438922A
Cited
US3454621A
Cited
US3489744A
Cited
US3668186A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-01-19 | 1979-07-21 | 1980-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-19 | 1983-07-21 | 1984-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-19 | 1987-07-21 | 1988-01-20 | $7700.00 | Window Closed / Lapsed |