Method of producing a vehicle glass assembly

1. A method of producing a vehicle glass assembly, comprising:

(A) providing a connector made of metal plate and comprising a first flat portion, a second flat portion and a bridge portion connecting between the first and the second flat portions, said flat portions respectively having first and second surfaces for soldering,

(B) soldering lead-free solder onto said surfaces to form first and second blocks of lead-free solder on the first and second surfaces, respectively,

(C) providing a glass substrate layer on which an electrically conductive layer comprising a wire pattern and a busbar is formed, and

(D) sandwiching the lead-free solder blocks between their respective surfaces and the busbar, and then melting the blocks to form lead-free solder layers by solder connections between the connector and the busbar;

wherein the amount of lead-free solder in each of the blocks is between 15 mg and 50 mg,

wherein each block on the first and second surfaces is away from and disposed within all edges of the surfaces for soldering of the first and the second flat portions,

wherein all lead-free solders are disposed between the first and the second flat portions and the busbar in the solder connections.

2. The production method according to claim 1 , wherein the amount of lead-free solder in each of the blocks is from 20 mg to less than 45 mg.

3. The production method according to claim 1 , wherein the area of each of said first and second surfaces is between 10 mm 2 and 28 mm 2 .

4. The production method according to claim 1 , wherein the thickness of the metal plate forming the connector is between 0.5 mm and 0.8 mm.

5. The production method claim 1 , wherein the volume of each block is between 2 mm 3 and 12 mm 3 .

6. The production method according to claim 1 , wherein the thickness of each block is between 0.3 mm and 0.5 mm.

7. The production method according to claim 1 , wherein all lead-free solders recesses from all edges of the first and the second flat portions.

8. The production method according to claim 1 , wherein the shape of the first and second flat portions is a rectangle, a square, an oval, or a circle.

9. The production method according to claim 1 , wherein the metal plate is made of Cu, a Cu alloy, or an Fe alloy comprising Ni or Cr.

10. The production method according to claim 1 , wherein the distance between the first and second flat portions is between 4 mm and 15 mm.

11. The production method according to claim 1 , wherein the lead-free solder contains tin as a major component.

12. The production method according to claim 1 , wherein the lead-free solder is an Sn-Ag based solder or an Sn-Ag-Cu based solder.

13. The production method according to claim 12 , wherein the lead-free solder contains 95-99 mass % of Sn, 1-5 mass % of Ag, and 0-1.5 mass % of Cu.

14. The production method according to claim 1 , wherein each lead-free solder layer is thinner than each block in thickness.

15. The production method according to claim 1 , wherein the blocks are melted in the step (D) by using a soldering iron or by electrical heating of the connector.

16. The production method according to claim 1 , wherein each lead-free solder layer has a thickness that is between 0.1 mm to 0.3 mm.

17. A method of producing a vehicle glass assembly, comprising:

(A) providing a connector made of metal plate and comprising a first flat portion, a second flat portion and a bridge portion connecting between the first and the second flat portions, said flat portions respectively having first and second surfaces for soldering,

(B) soldering lead-free solder onto said surfaces to form first and second blocks of lead-free solder on the first and second surfaces, respectively,

(C) providing a glass substrate layer on which an electrically conductive layer comprising a wire pattern and a busbar is formed, and

(D) sandwiching the lead-free solder blocks between their respective surfaces and the busbar, and then melting the blocks to form lead-free solder layers by solder connections between the connector and the busbar;

wherein the amount of lead-free solder in each of the blocks is between 20 mg and less than 45 mg,

wherein each block on the first and second surfaces is away from and disposed within all edges of the surfaces for soldering of the first and second flat portions,

wherein all lead-free solders are disposed between the first and the second flat portions and the busbar in the solder connections,

wherein the area of each of said first and second surfaces is between 10 mm 2 and 28 mm 2 ,

wherein the thickness of the metal plate forming the connector is between 0.5 mm and 0.8 mm,

wherein the volume of each block is between 2 mm 3 and 12 mm 3 ,

wherein the thickness of each block is between 0.3 mm and 0.5 mm,

wherein all lead-free solders recesses from all edges of the first and the second flat portions.

18. The production method according to claim 17 , wherein the lead-free solder is an Sn-Ag based solder or an Sn-Ag-Cu based solder.

19. The production method according to claim 18 , wherein the lead-free solder contains 95-99 mass % of Sn, 1-5 mass % of Ag, and 0-1.5 mass % of Cu.

20. The production method according to claim 17 , wherein the blocks are melted in the step (D) by using a soldering iron or by electrical heating of the connector.