US3884772A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for producing a heat exchanger element
Assignee: Furukawa Electric Co Ltd
•
Filing: 1972-09-25
•
Granted: 1975-05-20
•
Expires: 1992-09-25
Abstract
Abstract Heat exchanger element having a porous layer electrodeposited thereon from an electrodeposition solution containing finely divided electroconductive particles and a source of the metal ions to be deposited, which element shows excellent performance characteristics and good workabilities.
Inventors
- 👤 Shoji Shiga
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 00:51
CPC Classifications
C; C25; C25D; C25D15/00; C25D15/02
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
168 words
A METHOD OF PRODUCING A HEAT EXCHANGER ELEMENT HAVING A POROUS SURFACE LAYER CONTAINING ELECTRODEPOSIED METAL AND FINELY DIVIDED ELECTROCONDUCTIVE PARTICLES, WHICH COMPRISES IMMERSING A SUBSTRATE FOR THE HEAT EXCHANGE SURFACES IN A METAL-ELECTRODEPOSITING SOLUTION CONTAINING A SOURCE OF THE METAL IONS WHICH ARE TO BE DEPOSITED ON THE SUBSTRATE AND SUSPENDED FINELY DIVIDED ELECTRONCONDUCTIVE METAL PARTICLES HAVING AN AVERAGE PARTICLE SIZE OF ABOUT 0.5 TO 500 MICRONS IN A CONCENTRATION OF 5 TO 500 G/L, AND CREATING A POTENTIAL DIFFERENCE BETWEEN THE SUBSTRATE, CONNECTED AS THE CATHODE, AND AN ANODE IN THE SOLUTION, UNDER CONDITIONS SATISYING THE FORMULA 0.6T+16>DC>0.75T-18 WHEREIN T IS THE TEMPERATURE OF THE SOLUTION IN *C AND DC IS THE CATHODE CURRENT DENSITY IN A/DM2 WITHIN THE RANGE OF 10-40 A/DM2, SO AS TO DEPOSIT A MIXTURE OF THE ELECTROCONDUCTIVE METAL PARTICLES AND METAL ON THE SUBSTRATE IN WEIGHT RATIO OF PARTICLES TO METAL OF NOT GREATER THAN 1:3 AND FORM POROUS PROJECTIONS HAVING A HEIGHT OF AT LEAST 0.05 MM ON THE SUBSTRATE.
Claim 2
Independent Claim
168 words
A METHOD OF PRODUCING A HEAT EXCHANGER ELEMENT HAVING A POROUS SURFACE LAYER CONTAINING ELECTRODEPOSIED METAL AND FINELY DIVIDED ELECTROCONDUCTIVE PARTICLES, WHICH COMPRISES IMMERSING A SUBSTRATE FOR THE HEAT EXCHANGE SURFACES IN A METAL-ELECTRODEPOSITING SOLUTION CONTAINING A SOURCE OF THE METAL IONS WHICH ARE TO BE DEPOSITED ON THE SUBSTRATE AND SUSPENDED FINELY DIVIDED ELECTRONCONDUCTIVE METAL PARTICLES HAVING AN AVERAGE PARTICLE SIZE OF ABOUT 0.5 TO 500 MICRONS IN A CONCENTRATION OF 5 TO 500 G/L, AND CREATING A POTENTIAL DIFFERENCE BETWEEN THE SUBSTRATE, CONNECTED AS THE CATHODE, AND AN ANODE IN THE SOLUTION, UNDER CONDITIONS SATISYING THE FORMULA 0.6T+16>DC>0.75T-18 WHEREIN T IS THE TEMPERATURE OF THE SOLUTION IN *C AND DC IS THE CATHODE CURRENT DENSITY IN A/DM2 WITHIN THE RANGE OF 10-40 A/DM2, SO AS TO DEPOSIT A MIXTURE OF THE ELECTROCONDUCTIVE METAL PARTICLES AND METAL ON THE SUBSTRATE IN WEIGHT RATIO OF PARTICLES TO METAL OF NOT GREATER THAN 1:3 AND FORM POROUS PROJECTIONS HAVING A HEIGHT OF AT LEAST 0.05 MM ON THE SUBSTRATE.
Claim 3
Dependent Claim
17 words
A method according to claim 1, wherein the finely divided electroconductive metal particles comprise irregular shaped powder.
Claim 4
Dependent Claim
17 words
A method according to claim 2, wherein the irregular shaped powder comprises dendritic powder or spongy powder.
Claim 5
Dependent Claim
37 words
A method according to claim 1, wherein electroconductive metal powder having spherical shape or substantially spherical shape is used as the finely divided electroconductive metal particles, thereby forming a porous layer having a number of porous projections.
Claim 6
Independent Claim
184 words
A method of producing a heat exchanger element having a porous surface layer containing electrodeposited copper and finely divided electroconductive particles, which comprises immersing a substrate for heat exchange surfaces in a copper-electrodepositing solution containing a source of the copper ions which are to be deposited on the substrate, suspended finely divided electroconductive irregular-shaped metal particles having an average particle size of about 0.5 to 500 microns in a concentration of 5 to 500 g/l, and glue, gelatine or a hydrolyte thereof in a concentration of 1 to 500 mg/l, and creating a potential difference between the substrate, connected as the cathode, and an anode in the solution, under conditions satisfying the formula 0.6 T+16>Dc>0.75 T-18 wherein T is the temperature of the solution in *C and Dc is the cathode current density in A/dm2 within the range of 10-40 A/dm2, so as to deposit a mixture of the electroconductive particles and copper on the substrate in a weight ratio of particles to copper of not greater than 1:3 and form porous projections having a height of at least 0.05 mm on the substrate.
Claim 7
Independent Claim
184 words
A method of producing a heat exchanger element having a porous surface layer containing electrodeposited copper and finely divided electroconductive particles, which comprises immersing a substrate for heat exchange surfaces in a copper-electrodepositing solution containing a source of the copper ions which are to be deposited on the substrate, suspended finely divided electroconductive irregular-shaped metal particles having an average particle size of about 0.5 to 500 microns in a concentration of 5 to 500 g/l, and glue, gelatine or a hydrolyte thereof in a concentration of 1 to 500 mg/l, and creating a potential difference between the substrate, connected as the cathode, and an anode in the solution, under conditions satisfying the formula 0.6 T+16>Dc>0.75 T-18 wherein T is the temperature of the solution in *C and Dc is the cathode current density in A/dm2 within the range of 10-40 A/dm2, so as to deposit a mixture of the electroconductive particles and copper on the substrate in a weight ratio of particles to copper of not greater than 1:3 and form porous projections having a height of at least 0.05 mm on the substrate.
Claim 8
Dependent Claim
50 words
A method according to claim 5, wherein the copper-electrodepositing solution comprises such an amount of copper fluobrate sufficient to provide a copper content of 40 to 200 g/l and an amount of hydrofluoboric acid such that the pH of the solution is maintained in a range of 0.2 to 0.9.
Claim 9
Dependent Claim
22 words
A method according to claim 5, wherein the finely divided electroconductive irregular-shaped metal particles comprise dendritic copper powder or spongy copper powder.
Claim 10
Dependent Claim
22 words
A method according to claim 7, wherein the finely divided electroconductive irregular-shaped metal particles are dendritic copper powder or spongy copper powder.
Claim 11
Dependent Claim
37 words
A method according to claim 5, wherein the electrodepositing solution is prepared using an amount of copper sulfate sufficient to provide a copper content of 40 to 100 g/l, and 5 to 200 g/l of sulphuric acid.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-19 | 1978-11-18 | 1979-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-19 | 1982-11-18 | 1983-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-19 | 1986-11-18 | 1987-05-20 | $7700.00 | Window Closed / Lapsed |