Silver layer formed by electrosilvering substrate material
View Patent ↗The inventors have conducted vigorous studies, and discovered as a result that it is possible to form a silver layer having a high reflectance of about 90 to 99% in a visible light area by setting a grain size of an outermost surface of a silver plated layer within a range of 0.5 μm or more to 30 μm or less.
1. A silver layer formed by electrosilvering a substrate material, wherein a grain size of an outermost surface is within a range of 1 μm or more to 30 μm or less, and wherein a surface roughness Ry of the substrate material is 0.5 μm or more,
and wherein a reflectance of the silver layer is within a range of 90 to 99% in a wavelength range between 400 to 700 nm.
2. The silver layer according to claim 1 , wherein a silver plated layer has a film thickness of 1 μm or more, and the substrate material is formed of copper.
3. The silver layer according to claim 1 , wherein a silver plated layer has a film thickness of 4 μm or more, and the substrate material is formed of nickel.
4. The silver layer according to claim 3 , wherein the substrate material contains no sulfur.
5. A method for manufacturing the silver layer according to claim 1 , comprising the steps of:
heating a silver plated layer at a temperature of 200° C. or more for 30 seconds or more after the electrosilvering.
6. A method for manufacturing the silver layer according to claim 1 , comprising the steps of:
carrying out the electrosilvering by low-cyan bathing.
7. A LED mounted substrate comprising, the silver layer according to claim 1 as a reflective surface.
8. A method for manufacturing the LED mounted substrate according to claim 7 , comprising the steps of:
forming a conductive layer on a substrate surface;
patterning the conductive layer to form a circuit pattern;
forming a copper plated layer on the circuit pattern;
forming a nickel plated layer on the copper plated layer; and
forming a silver plated layer on the nickel plated layer.
9. A light emitting diode package comprising:
a light emitting diode; and a LED mounted substrate mounting the light emitting diode, the LED mounted substrate comprising:
a substrate material; and
a silver layer as a reflective surface, wherein the silver layer comprises a silver plated layer formed by electrosilvering of the substrate material; a grain size of an outermost surface of the silver plated layer is within a range of 1 μm or more to 30 μm or less; and a surface roughness Ry of the substrate material is 0.5 μm or more,
and wherein a reflectance of the silver layer is within a range of 90 to 99% in a wavelength range between 400 to 700 nm.
10. The light emitting diode package according to claim 9 , wherein the silver plated layer has a film thickness of 1 μm or more, and the substrate material is formed of copper.
11. The light emitting diode package according to claim 9 , wherein the silver plated layer has a film thickness of 4 μm or more, and the substrate material is formed of nickel.
12. The light emitting diode package according to claim 11 , wherein the substrate material contains no sulfur.