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US4261965A Expired / Lapsed US ⏱️ 0.0 years remaining

Basic zinc compound flake-like crystalline particle and method for preparation thereof

Assignee: Panasonic Holdings Corp
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Filing: 1979-06-14
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Granted: 1981-04-14
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Expires: 1999-06-14
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Abstract

Abstract Basic zinc compound flake-like crystalline material suited for use in crystal-oriented electronic devices and method for preparation thereof comprising the steps of preparing a solution including at least zinc ions and sulfate ions, and causing precipitation of zinc sulfate crystals by causing a reaction of components of said solution with alkali when said solution is at a temperature in the range 50 DEG to 100 DEG C. and has a pH value of in the range 4 to 6.5.

Inventors

  • 👤 Yoji Fukuda
  • 👤 Tsuneharu Nitta
  • 👤 Tomizo Matsuoka
  • 👤 Fumio Fukushima
  • 👤 Shigeru Hayakawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 23:08
CPC Classifications
C; C01; C01G; C01G9/00; C01G9/06

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 158 words
Method for preparing flake-like crystalline particles of the formula ZnSO 4 .XZn(OH) 2 wherein X=1.7-4.8, having a ratio of thickness to diameter of 1:5 to 1:300 and a diameter of 1 μm or more which comprises: (a) preparing a solution of 0.1 to 6 moles per liter of no more than two zinc salts selected from the group consisting of zinc nitrate, zinc sulfate, zinc acetate, zinc chloride and zinc iodide and wherein and wherein at least 25 mol percent of said zinc salts is zinc sulfate: (b) precipitating the flake-like crystalline particles at a temperature of 80° to 100° C. and a pH of 4.0 to 6.5 by the gradual addition of urea to said solution of step (a) and (c) separating said flake-like crystalline particles from said solution whereby said flakes have a thickness to diameter ratio of from 2-10 times that obtained when all of the urea to be added is present in step (a).
Claim 2
Dependent Claim 158 words
Method for preparing flake-like crystalline particles of the formula ZnSO 4 .XZn(OH) 2 wherein X=1.7-4.8, having a ratio of thickness to diameter of 1:5 to 1:300 and a diameter of 1 μm or more which comprises: (a) preparing a solution of 0.1 to 6 moles per liter of no more than two zinc salts selected from the group consisting of zinc nitrate, zinc sulfate, zinc acetate, zinc chloride and zinc iodide and wherein and wherein at least 25 mol percent of said zinc salts is zinc sulfate: (b) precipitating the flake-like crystalline particles at a temperature of 80° to 100° C. and a pH of 4.0 to 6.5 by the gradual addition of urea to said solution of step (a) and (c) separating said flake-like crystalline particles from said solution whereby said flakes have a thickness to diameter ratio of from 2-10 times that obtained when all of the urea to be added is present in step (a).
Claim 3
Dependent Claim 11 words
Method according to claim 1 wherein the urea is added dropwise.
Claim 4
Dependent Claim 23 words
Method according to claim 1 wherein said zinc salts contain zinc iodide in an amount of 25 mol % of said zinc salts.
Claim 5
Dependent Claim 24 words
Method according to claim 1, wherein said zinc salts contain zinc nitrate in an amount up to 75 mol % of said zinc salts.
Claim 6
Dependent Claim 24 words
Method according to claim 1, wherein said zinc salts contain zinc acetate in an amount up to 50 mol % of said zinc salts.
Claim 7
Dependent Claim 24 words
Method according to claim 1, wherein said zinc salts contain zinc chloride in an amount up to 25 mol % of said zinc salts.

References Cited (Backward Citations)

CA572977A Cited
US1444484A Cited
US1430269A Cited
US1912332A Cited
US2602727A Cited
US3136647A Cited
US3545994A Cited
US3919403A Cited
SU513008A1 Cited
US4069299A Cited
DE2757914A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-04-13 1984-10-13 1985-04-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-04-13 1988-10-13 1989-04-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-04-13 1992-10-13 1993-04-14 $7700.00 Window Closed / Lapsed

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