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US2838473A Expired / Lapsed US ⏱️ 0.0 years remaining

Rapid method for producing stable novolaks

Assignee: Dow Chemical Co
•
Filing: 1953-09-28
•
Granted: 1958-06-10
•
Expires: 1973-09-28
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Abstract

No abstract record available.

Inventors

  • 👤 Alexander M Partansky
  • 👤 Jr Mack A King

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 05:50
CPC Classifications
C; C08; C08G; C08G8/00; C08G8/04; C08G8/08; C08G8/10

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 148 words
THE RAPID METHOD FOR MAKING A STABLE NOVOLAK FROM PHENOL AND FORMALDEHYDE WHICH COMPRISES SUPPLYING TO A PRESSURE VESSEL A MIXTURE CONSISTING ESSENTIALLY OF (A) PHENOL, (B) FROM 0.5 TO 0.9 MOL OF FORMALDEHYDE PER MOL OF PHENOL, (C) FROM 0.5 TO 2 TIMES AS MUCH WATER AS PHENOL BY WEIGHT AND (D) FROM 0.1 TO 5 PERCENT, BASED ON THE WEIGHT OF PHENOL, OF A STRONG MINERAL ACID, CLOSING THE VESSEL, SUPPLYING HEAT TO THE MIXTURE ONLY UNTIL VIGOROUS EXOTHERMIC REACTION IS FIRST EVIDENCED, MAINTAINING THE MIXTURE IS SAID CLOSED VESSEL UNDER THE VARYING AUTOGENOUS SUPERATMOSPHERIC PRESSURE UNTIL THE TEMPERATURE AND PRESSURE VALUES CEASE RISING AND START TO DECLINE; AND THEN ALLOWING THE CLOSED VESSEL AND THE MIXTURE THEREIN TO COOL BY UNAIDED RADIATION TO A TEMPERATURE BELOW 150*C., AND THEREAFTER COOLING THE MIXTURE INA THE CLOSED VESSEL UNTIL THE PRESSURE IN THE VESSEL IS ATMOSPHERIC PRESSURE.
Claim 2
Dependent Claim 148 words
THE RAPID METHOD FOR MAKING A STABLE NOVOLAK FROM PHENOL AND FORMALDEHYDE WHICH COMPRISES SUPPLYING TO A PRESSURE VESSEL A MIXTURE CONSISTING ESSENTIALLY OF (A) PHENOL, (B) FROM 0.5 TO 0.9 MOL OF FORMALDEHYDE PER MOL OF PHENOL, (C) FROM 0.5 TO 2 TIMES AS MUCH WATER AS PHENOL BY WEIGHT AND (D) FROM 0.1 TO 5 PERCENT, BASED ON THE WEIGHT OF PHENOL, OF A STRONG MINERAL ACID, CLOSING THE VESSEL, SUPPLYING HEAT TO THE MIXTURE ONLY UNTIL VIGOROUS EXOTHERMIC REACTION IS FIRST EVIDENCED, MAINTAINING THE MIXTURE IS SAID CLOSED VESSEL UNDER THE VARYING AUTOGENOUS SUPERATMOSPHERIC PRESSURE UNTIL THE TEMPERATURE AND PRESSURE VALUES CEASE RISING AND START TO DECLINE; AND THEN ALLOWING THE CLOSED VESSEL AND THE MIXTURE THEREIN TO COOL BY UNAIDED RADIATION TO A TEMPERATURE BELOW 150*C., AND THEREAFTER COOLING THE MIXTURE INA THE CLOSED VESSEL UNTIL THE PRESSURE IN THE VESSEL IS ATMOSPHERIC PRESSURE.

References Cited (Backward Citations)

US924449A Cited
US1660403A Cited
US2456192A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1961-06-09 1961-12-09 1962-06-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1965-06-09 1965-12-09 1966-06-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1969-06-09 1969-12-09 1970-06-10 $7700.00 Window Closed / Lapsed

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