US4490496A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Moistureproof insulating coating composition for packing circuit boards
Assignee: Hitachi Ltd
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Filing: 1983-02-28
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Granted: 1984-12-25
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Expires: 2003-02-28
Abstract
Abstract A coating composition comprising (A) a thermoplastic resin having a glass transition temperature of 0 DEG to 80 DEG C., (B) a compound having 2 or more hydroxyl groups in the molecule, (C) a thixotropic agent and (D) a solvent, and said coating composition having a viscosity of 3 to 50 poises at 25 DEG C. and a thixotropy of 2 or more can give a moistureproof insulating coating film with uniform and large thickness and very few bubbles by one-time treatment over packing circuit boards.
Inventors
- 👤 Iwao Maekawa
- 👤 Eiji Omori
- 👤 Isao Uchigasaki
- 👤 Hideyuki Tobita
- 👤 Naoki Yokoyama
- 👤 Seikichi Tanno
- 👤 Fumio Nakano
- 👤 Ren Ito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:23
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/22; H05K3/28; H05K3/285; C; C09; C09D; C09D133/00; C09D133/04; C09D133/06
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
170 words
A moistureproof insulating coating composition for packing circuit boards comprising: (A) 20 to 60 parts by weight of a thermoplastic resin having a glass transition temperature of 0° to 80° C., said thermoplastic resin being an acrylic resin obtained by polymerizing alkyl esters of acrylic acid or methacrylic acid alone or a mixture thereof, or a urethane resin; (B) 0.01 to 1 part by weight of at least one compound selected from the group consisting of a dihydric alcohol, a trihydric alcohol, a vegetable oil having two or more hydroxyl groups in a molecule and a surface active agent having two or more hydroxyl groups in a molecule; (C) 0.1 to 10 parts by weight of at least one thixotropic agent selected from the group consisting of powdered silicon oxide, magnesium oxide, and aluminum hydroxide; and (D) 40 to 80 parts by weight of at least one organic solvent; said coating composition having a viscosity of 3 to 50 poises at 25° C. and a thixotropy of 2 or more.
Claim 2
Dependent Claim
170 words
A moistureproof insulating coating composition for packing circuit boards comprising: (A) 20 to 60 parts by weight of a thermoplastic resin having a glass transition temperature of 0° to 80° C., said thermoplastic resin being an acrylic resin obtained by polymerizing alkyl esters of acrylic acid or methacrylic acid alone or a mixture thereof, or a urethane resin; (B) 0.01 to 1 part by weight of at least one compound selected from the group consisting of a dihydric alcohol, a trihydric alcohol, a vegetable oil having two or more hydroxyl groups in a molecule and a surface active agent having two or more hydroxyl groups in a molecule; (C) 0.1 to 10 parts by weight of at least one thixotropic agent selected from the group consisting of powdered silicon oxide, magnesium oxide, and aluminum hydroxide; and (D) 40 to 80 parts by weight of at least one organic solvent; said coating composition having a viscosity of 3 to 50 poises at 25° C. and a thixotropy of 2 or more.
Claim 3
Dependent Claim
18 words
A coating composition according to claim 1, wherein the compound (B) is castor oil or polyoxyethylene sorbitan monolaurate.
Claim 4
Dependent Claim
15 words
A coating composition according to claim 1, wherein the thixotropic agent is powered silicon oxide.
Claim 5
Dependent Claim
29 words
A coating composition according to claim 1, wherein the coating composition has a viscosity of 10 to 30 poises at 25° C. and a thixotropy of 3 to 6.
Claim 6
Dependent Claim
30 words
A coating composition according to claim 1, wherein said solvent is at least one member selected from the group consisting of ketones, aromatic series solvents, ester series solvents and alcohols.
Claim 7
Dependent Claim
19 words
A coating composition according to claim 1, wherein said composition consists essentially of components (A), (B), (C) and (D).
Claim 8
Dependent Claim
117 words
A moistureproof insulating coating composition for packing circuit boards comprising: (A) 20 to 60 parts by weight of a thermoplastic resin having a glass transition temperature of 0° to 80° C., said resin being an acrylic resin obtained by polymerizing alkyl esters of acrylic acid or methacrylic acid alone or a mixture thereof, or a urethane resin; (B) 0.01 to 1 part by weight of polyoxyethylene sorbitan monolaurate; (C) 0.1 to 10 parts by weight of powdered silicon oxide; and (D) 40 to 80 parts by weight of a mixture of toluene and methyl ethyl ketone; said coating composition having a viscosity of 3 to 50 poises at 25° C. and a thixotropy of 2 or more.
Claim 9
Dependent Claim
117 words
A moistureproof insulating coating composition for packing circuit boards comprising: (A) 20 to 60 parts by weight of a thermoplastic resin having a glass transition temperature of 0° to 80° C., said resin being an acrylic resin obtained by polymerizing alkyl esters of acrylic acid or methacrylic acid alone or a mixture thereof, or a urethane resin; (B) 0.01 to 1 part by weight of polyoxyethylene sorbitan monolaurate; (C) 0.1 to 10 parts by weight of powdered silicon oxide; and (D) 40 to 80 parts by weight of a mixture of toluene and methyl ethyl ketone; said coating composition having a viscosity of 3 to 50 poises at 25° C. and a thixotropy of 2 or more.
Claim 10
Dependent Claim
16 words
A coating composition according to claim 7, wherein the thermoplastic resin (A) is an acrylic resin.
Claim 11
Dependent Claim
16 words
A coating composition according to claim 7, wherein the thermoplastic resin (A) is a urethane resin.
Claim 12
Dependent Claim
16 words
A coating composition according to claim 1, wherein the thermoplastic resin (A) is an acrylic resin.
Claim 13
Dependent Claim
16 words
A coating composition according to claim 1, wherein the thermoplastic resin (A) is a urethane resin.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-12-25 | 1988-06-25 | 1988-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-25 | 1992-06-25 | 1992-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-25 | 1996-06-25 | 1996-12-25 | $7700.00 | Window Closed / Lapsed |