METHOD FOR PRODUCING A DISK WITH AN ELECTRICALLY CONDUCTIVE COATING AND A METAL STRIP WHICH IS SOLDERED ONTO THE DISK; AND CORRESPONDING DISK

Abstract

A method for producing a pane with an electrically conductive coating and a metallic strip soldered thereon is described. The method includes providing a substrate with an electrically conductive coating, providing a metallic strip with at least one through-hole, positioning the metallic strip on the electrically conductive coating, wherein the hole is arranged on the electrically conductive coating, and soldering the metallic strip to the electrically conductive coating via a soldering compound using an ultrasonic soldering tip.

Claims

1.-15. (canceled)

16. A method for producing a pane with an electrically conductive coating and a metallic strip soldered thereon, comprising: (a) providing a substrate with an electrically conductive coating, (b) providing a metallic strip with at least one through hole, (c) positioning the metallic strip on the electrically conductive coating, wherein the at least one through hole is placed on the electrically conductive coating, and (d) soldering the metallic strip to the electrically conductive coating via a soldering compound and using an ultrasonic soldering tip.

17. The method according to claim 16, wherein the ultrasonic soldering tip is brought into contact with a top of the metallic strip and is moved over the hole and the metallic strip surrounding the hole..

18. The method according to claim 16, wherein the soldering compound is melted by heat generated during soldering.

19. The method according to claim 16, wherein the soldering compound is provided in step (b) and the soldering compound is placed on one of i) bottom, ii) top, or iii) bottom and top of the metallic strip.

20. The method according to claim 16, wherein the metallic strip is provided with an adhesive on bottom, the adhesive surrounding the hole and the soldering compound.

21. The method according to claim 20, wherein the adhesive is a double-sided adhesive tape.

22. The method according to claim 16, wherein the metallic strip is a flat conductor, extending from the electrically conductive coating to beyond a side edge of the substrate.

23. The method according to claim 16, wherein the hole has shape of a slit.

24. The method according to claim 16, wherein the electrically conductive coating comprises a printed-on conductive paste.

25. The method according to claim 24, wherein the conductive paste comprises silver particles and glass frits.

26. The method according to claim 16, wherein the metallic strip has a thickness of 10 μm to 500 μm.

27. The method according to claim 16, wherein the metallic strip has a thickness of 30 μm to 200 μm and comprises copper or silver.

28. The method according to claim 16, wherein the substrate comprises glass.

29. The method according to claim 28, wherein the glass is a soda lime glass.

30. A pane with an electrically conductive coating and a metallic strip soldered thereon, comprising: a substrate with an electrically conductive coating, a metallic strip with a bottom facing the substrate and a top (facing away from the substrate, wherein: the metallic strip is mounted on the electrically conductive coating using a soldering compound; the metallic strip comprises a through hole, and the soldering compound is placed on a region of the bottom surrounding the hole, within the hole, and on a region of the top surrounding the hole.

31. The pane according to claim 30, further comprising an adhesive surrounding a portion of the soldering compound placed on the bottom, the adhesive being placed between the substrate and the metallic strip.

32. The pane according to claim 30, wherein the substrate is laminated via a thermoplastic intermediate layer to another pane to form a composite pane, wherein: the electrically conductive coating and the metallic strip are arranged on a surface of the substrate facing the thermoplastic intermediate layer, and the metallic strip extends from the electrically conductive coating to beyond a side edge of the composite pane.

33. The pane according to claim 30, wherein: the substrate has an electrically conductive thin-film system; the electrically conductive coating is applied on the thin-film system thereby forming two current collecting rails; the electrically conductive coating comprises a printed-on conductive paste; a metallic strip with a through-hole is soldered onto each current collecting rail, the metallic strip being a flat conductor providing electrical connection to an external voltage source; and the substrate is laminated via a thermoplastic intermediate layer to another pane to form a composite pane.

34. A method of using a pane comprising: providing the pane according to claim 30; providing heatable window panes or glazings with electrically switchable optical properties, and using the pane in the heatable window panes or glazings with electrically switchable optical properties.

Description

[0068] They depict:

[0069] FIG. 1 a plan view of an embodiment of the pane according to the invention,

[0070] FIG. 2 a plan view of the top O of embodiment according to the invention of the metallic strip before soldering,

[0071] FIG. 3 a plan view of the bottom U of the metallic strip of FIG. 2,

[0072] FIG. 4 a section along B-B′ through the metallic strip of FIGS. 2 and 3,

[0073] FIG. 5 a section along A-A′ through the pane of FIG. 1 in the region of the soldered-on metallic strip 3,

[0074] FIG. 6 a section along B-B′ through another embodiment of the metallic strip,

[0075] FIG. 7 a section along B-B′ through another embodiment of the metallic strip,

[0076] FIG. 8 a plan view of a foil conductor with a metallic strip,

[0077] FIG. 9 a section along C-C′ through the foil conductor of FIG. 6,

[0078] FIG. 10 a section through another embodiment of the metallic strip,

[0079] FIG. 11 a flowchart of an embodiment of the method according to the invention.

[0080] FIG. 1 and FIG. 5 depict in each case a detail of an embodiment of the pane according to the invention. The pane comprises a substrate 1, which is, for example, a 2.1-mm-thick glass pane made of soda lime glass. One surface of the substrate 1 is provided with an electrically conductive thin-film system 7. The thin-film system 7 contains, for example, at least one electrically conductive layer based on indium tin oxide (ITO) and is provided as a surface electrode of an electrochromic glazing. A peripheral edge region of the substrate 1 is not provided with the thin-film system 7. For the intended use, the thin-film system 7 must be connected to an external voltage source such that the switching state of the electrochromic glazing can be varied by means of the voltage applied. For this, an electrically conductive coating 2 is applied on the thin-film system 7. The coating 2 forms two current collecting rails along two opposite side edges of the substrate 1. The coating 2 is a printed-on and fired screenprinting paste containing silver particles and glass frits. For the connection of the current collecting rails to the external voltage source, a metallic strip 3 is soldered onto each current collecting rail. The metallic strip 3 is a strip of a copper foil with a thickness of 50 μm and runs from the coating 2 beyond the side edge of the pane.

[0081] The metallic strip 3 is soldered onto the coating 2 using ultrasonic soldering (US soldering). The metallic strip 3 has a hole 4, which runs through from its top O to its bottom U. Here, the top O is the surface of the strip facing away from the substrate 1: the bottom U, the surface of the strip facing the substrate 1. A flux free soldering compound 5 suitable for US soldering durably stably connects the strip 3 to the coating 2. The soldering compound 5 is arranged between the bottom U of the strip 3 facing the substrate 1 and the coating 2, and, to be sure, on a region of the bottom U surrounding the hole 4. The soldering compound is further arranged within the hole 4 as well as on a region on the top O of the strip 3 surrounding the hole 4. By means of this “mushroom-shaped” arrangement of the soldering compound 5, a particularly stable soldered connection is obtained. A suitable soldering compound 5 is, for example, flux-free In97Ag3.

[0082] An adhesive 6, namely a double-sided adhesive tape, is applied on the bottom U of the strip 3. The adhesive tape completely surrounds the hole 4 and the soldering compound 5. The adhesive 6, the strip 3, and the substrate 1 with the coating 2 form a cavity that is opened only by the hole 4.

[0083] FIG. 2, FIG. 3, and FIG. 4 depict in each case a detail of a suitable metallic strip 3 before soldering. The strip 3 has a slit-shaped hole 4 with a length of 6 mm and a width of 1.5 mm. This size of the hole is ideally suited for soldering with a soldering tip with a diameter of 3 mm. A double-sided adhesive tape that surrounds the hole 4 is applied on the bottom U as adhesive 6. Adjacent the hole 4 and within the region surrounded by the adhesive 6, two depots of a soldering compound 5 with the layer thickness of 100 μm are also applied on the bottom U. The layer thickness of the soldering compound 5 preferably corresponds to the thickness of the adhesive 6. If the metallic strip is additionally provided with polymeric sheathing, the layer thickness of the soldering compound 5 preferably corresponds to the sum of the thickness of the adhesive 6 and the thickness of the sheathing. Two more soldering compound portions 5 are applied oppositely on the top O.

[0084] The arrangement of the soldering compound 5 both on the top O and on the bottom U is advantageous with regard to the formation of a “mushroom-shaped” soldering compound after the soldering operation as depicted in FIG. 5.

[0085] For soldering, the strip 3 is placed on the the electrically conductive coating 2 such that the bottom U faces the substrate 1 and the coating 2. During US soldering, a soldering tip is brought into contact with the top O and moved over the region to be soldered. The movement is done over the the hole 4 as well. Oxides and impurities are removed from the soldering compound 5 by the ultrasonic oscillations. They are not allowed to be distributed uncontrolledly over the substrate 1; but, instead, are retained in the cavity formed by the adhesive 6, the strip 3, and the coating 2. This is advantageous with regard to the quality of the coating 2 and, in particular, of the thin-film system 7, which would be negatively affected by distributed impurities. The soldering compound is also bonded to the surfaces of the strip 3 and of the coating 2 by the ultrasonic oscillations such that a mechanical bond is produced. When the soldering compound 5 is melted by increasing the temperature, the adhesive 6 also prevents uncontrolled outflow of the soldering compound 5. Instead, excess soldering compound 5 swells through the hole 4 of the strip 3 and thus forms the positive-fitting, “mushroom-shaped” soldering compound arrangement, as in FIG. 5. The solder connection can be produced in a single US soldering step; conventional touch-up soldering unnecessary. These are major advantages of the present invention.

[0086] FIG. 5 depicts a cross-section through the pane of FIG. 1 with the substrate 1, the thin-film system 7, the conductive coating 2, the metallic strip 3 with the hole 4, and the adhesive 6 as well as the “mushroom-shaped” arranged soldering compound 5.

[0087] FIG. 6 depicts a cross-section through another embodiment of the metallic strip 3 according to the invention with the adhesive 6 and the soldering compound 5 before soldering. In contrast to the embodiment of FIG. 4, the soldering compound portions are arranged not near the hole 4, but as soldering compound platelets such that they cover the hole 4. One soldering compound platelet is arranged in each case on the bottom U and on the top O of the strip 3. This arrangement as well favors the formation of the “mushroom-shaped” soldering compound 5 of FIG. 5 after the soldering operation.

[0088] FIG. 7 depicts a cross-section through another embodiment of the metallic strip 3 according to the invention with the adhesive 6 and the soldering compound 5 before soldering. The soldering compound 5 is pressed into the hole 4 and protrudes both over the top O and over the bottom U. This arrangement as well favors the formation of the “mushroom-shaped” soldering compound 5 of FIG. 5 after the soldering operation. By means of the pressing-in of the soldering compound 5, for example, using pliers, a very stable connection between the strip 3 and the soldering compound 5 is ensured.

[0089] FIG. 8 and FIG. 9 depict in each case a detail of a pre-assembled flat-band conductor. The flat-band conductor contains three metallic strips 3 that are implemented as strips of a copper foil in an insulating sheathing 10 made of plastic. The sheathing 10 is made, for example, of polyimide and has, for example, a thickness of 50 μm. Each strip 3 is provided with a slit-shaped hole 4. The sheathing 10 has, on both sides, i.e., on the top and the bottom in each case a circular recess 11 in the region of each hole 4. The recess 11 on the bottom serves for the soldered connection of the strip 3; the recess 11 on the top, for the contacting with the soldering tip during soldering. An adhesive 6 is preferably arranged on the sheathing 10 and surrounds the recess 11,

[0090] FIG. 10 depicts a cross-section through another embodiment of the metallic strip 3 with the hole 4 before soldering. The metallic strip 3 has a polymeric sheathing 10 with a thickness of 50 μm, which is removed in the region around the hole 4. There, the soldering compound 5 is applied on the bottom U and on the top O near the hole. The polymeric sheathing 10 on the bottom U is glued on the substrate 1 using an adhesive 6 with a thickness of 50 μm. The thickness of the soldering compound 5 is 100 μm, i.e., the sum of the thicknesses of the adhesive 6 and the sheathing 10. For the sake of clarity, the electrically conductive coating on the substrate 1 is not shown.

[0091] FIG. 11 depicts a flowchart of an exemplary embodiment of the method according to the invention for producing a pane according to the invention. A suitable frequency of the ultrasonic oscillations during soldering is, for example, 40 kHz. During soldering, the soldering compound 5 is preferably heated to a temperature of, for example, 315° C. and melted.

LIST OF REFERENCE CHARACTERS

[0092] (1) substrate

[0093] (2) electrically conductive coating

[0094] (3) metallic strip

[0095] (4) hole in the metallic strip 3

[0096] (5) soldering compound

[0097] (6) adhesive

[0098] (7) electrically conductive thin-film system

[0099] (10) insulating sheathing of 3

[0100] (11) recess in 10

[0101] O top of the metallic strip 3

[0102] U bottom of the metallic strip 3

[0103] A-A′ section line

[0104] B-B′ section line

[0105] C-C′ section line