CN114710891A - An apparatus and method for printing circuits on transparent materials - Google Patents

Abstract

The invention relates to the field of printed circuits, and relates to a device and method for printing circuits on transparent materials. The device includes a spraying mechanism and a laser processing mechanism, the spraying mechanism includes a spray head for spraying a solution, and the laser processing mechanism includes A control component and a laser are provided. The control component is used to control the movement speed, mechanism power and movement trajectory of the laser, and the laser is used to emit laser light to a transparent substrate for circuit etching. The invention does not need any printing equipment or mask, has simple process, low cost, low equipment dependence, high automation degree and high yield, and is suitable for mass production.

Description

An apparatus and method for printing circuits on transparent materials

technical field

The invention relates to the field of printed circuits, and relates to a device and method for printing circuits on transparent materials.

Background technique

In the traditional processing technology, printed circuits are mainly processed on non-transparent substrates. It is difficult and costly to print circuits on the surface of transparent substrates. With the development of the electronics industry, especially flexible electronics and wearable electronics It has become a hot spot of development, which has brought new market demand for transparent printed circuit boards.

At present, the method of printing a circuit on a transparent substrate is generally to first coat a layer of conductive film on the glass substrate, and then perform special treatment on the conductive film to form the conductive glass for the desired circuit. Cumbersome and long processing time. In addition, there is also a photolithography machine on the glass substrate, and the photolithography process is used to manufacture the circuit. However, the existing photolithography process needs to use photoresist as an insulating layer to make the circuit shape when manufacturing the circuit. Control, the process has higher quality requirements for the photoresist, the process is more complicated, the cost is higher, and the yield is lower.

When photoelectric glass is used in flexible electronics and wearable electronics, it is usually necessary to connect the circuit of the photoelectric glass with a larger area to the external driving circuit. It is necessary to use conductive double-sided tape or solder to encapsulate the flexible circuit board in two layers of photoelectric glass. It is connected to the circuit of the photoelectric glass, and then the flexible circuit board is connected to the external driving circuit, and the production efficiency is low. Damage to the circuit board will directly affect the display of the light-emitting diode, which will lead to the occurrence of unmodifiable defects in the product, and such defects cannot be repaired.

SUMMARY OF THE INVENTION

In order to improve the deficiencies of the prior art, the present invention provides a device and method for printing a circuit on a transparent substrate. In combination, after the laser beam passes through the back of the transparent substrate, the conductive layer cured on the surface of the transparent substrate is selectively peeled off, leaving the desired circuit lines, thereby obtaining a transparent substrate with circuits.

The invention provides a device for printing a circuit on a transparent substrate, comprising a spraying mechanism and a laser processing mechanism, the spraying mechanism includes a spray head for spraying a solution, the laser processing mechanism includes a control assembly and a laser, the control assembly It is used to control the movement speed, mechanism power and movement track of the laser, and the laser is used to emit laser light to the transparent substrate for circuit etching.

According to an embodiment of the present invention, the apparatus further includes a visual inspection mechanism, the visual inspection mechanism includes an imaging component and a recognition and judgment component, the imaging component and the recognition and judgment component are connected, and the imaging component is used for imaging the component to be tested , and send the image to the recognition and judgment component for recognition and judgment.

According to an embodiment of the present invention, the visual inspection mechanism further includes a feedback component, which is connected to the identification and judgment component for feeding back the judgment result. Preferably, the feedback component includes a display and/or an alarm, and the display uses a For displaying the judgment result, the alarm is used to give an alarm when the detection result is abnormal.

According to an embodiment of the present invention, the imaging assembly includes a camera, preferably a high-definition camera.

According to an embodiment of the present invention, the identifying and judging component includes a memory and a comparator, the memory is used to store the normal result, the comparator traverses the image, and judges whether there is an area on the image that is different from the normal result, if If yes, it is judged that the bit is abnormal, otherwise, it is judged to be normal.

According to an embodiment of the present invention, the laser processing mechanism further includes a cutting table and a position adjustment assembly, the position adjustment assembly is disposed above the cutting table, the laser and the imaging assembly are respectively disposed on the position adjustment assembly, and the control The assembly is connected with the position adjustment assembly, and is used for controlling the movement of the position adjustment assembly, thereby adjusting the positions of the laser and the imaging assembly.

According to an embodiment of the present invention, the spraying mechanism further includes an accommodating cavity for accommodating a solution to be sprayed, such as conductive ink.

According to an embodiment of the present invention, the spraying mechanism further includes a controller for adjusting the spraying speed of the spraying head, for example, adjusting the height of the spraying head.

According to the embodiment of the present invention, the laser processing mechanism includes any laser processing system with laser trajectory writing function, laser beam focusing function, and laser beam position control function, such as laser marking machine and laser marking machine.

According to an embodiment of the present invention, the laser comprises a fiber laser, a solid state laser, eg a solid state laser.

The present invention provides a method for printing a circuit on a transparent substrate, comprising the following steps:

1) spraying conductive ink on the surface of the transparent substrate and drying to obtain a transparent substrate with a cured layer;

2) emitting a laser from the side facing away from the cured layer to the transparent substrate, and etching the cured layer to form a circuit to obtain a transparent substrate with a circuit structure.

According to an embodiment of the present invention, before step 1), the method further comprises: cleaning the surface of the transparent substrate.

Optionally, use ethanol and/or acetone to clean both sides of the transparent substrate to remove dust, oil and other stains, so as to improve the adhesion of the circuit layer.

According to an embodiment of the present invention, the transparent substrate is selected from a transparent material with a low absorption coefficient of laser light, such as K9 glass, quartz, sapphire, transparent polymer film, and the like.

According to an embodiment of the present invention, the conductive ink in step 2) includes conductive particles and a solvent, and the conductive particles include one, two or one of nano-silver, nano-gold, nano-copper, nano-silver alloy, and nano-copper alloy. Various, such as nano-silver conductive ink.

According to an embodiment of the present invention, the content of silver in the nano-silver conductive ink is 30-50 wt %, preferably the content of silver in the nano-silver conductive ink is 35-45 wt %, and further, the content of silver in the nano-silver conductive ink is 38-42 wt%.

According to an embodiment of the present invention, the conductive ink is a viscous solution or a non-viscous solution, preferably a viscous solution, for example, the viscosity of the conductive ink is 50-200pa.s, preferably, the viscosity of the conductive ink is 80-150pa.s, further, the viscosity of the conductive ink is 100-120pa.s, such as 60pa.s, 70pa.s, 80pa.s, 90pa.s, 110pa.s, 130pa.s, 140pa.s. s, 160pa.s, 180pa.s, or any value in the range of any two-point value.

According to an embodiment of the present invention, the solvent in the conductive ink includes deionized water.

According to an embodiment of the present invention, the drying of the conductive ink in step 1) is performed under a constant temperature condition.

Preferably, the temperature of the constant temperature is 140-180 degrees Celsius, preferably 150-160 degrees Celsius, for example, 150 degrees Celsius.

According to an embodiment of the present invention, the time for the conductive ink to dry is greater than 15 minutes, preferably greater than 20 minutes, such as 20 minutes.

As an example, the drying is performed in a constant temperature oven at a temperature of 150 degrees Celsius for 20 minutes.

According to an embodiment of the present invention, the following step is further included between step 1) and step 2): detecting whether the transparent substrate with the cured layer is qualified.

According to an embodiment of the present invention, detecting whether the transparent substrate with a cured layer is qualified includes: observing whether the surface of the cured layer is defective, preferably by observing and judging by a visual inspection mechanism.

As an example, the imaging component images the surface of the cured layer and then transmits it to the visual inspection mechanism, and the visual inspection mechanism analyzes and judges the image, and when it is judged that the surface of the cured layer has defects, the current The transparent substrate with the cured layer is discarded.

According to an embodiment of the present invention, the defects include bubbles with a diameter greater than 20 microns and/or cracks with a length/width greater than 20 microns.

According to an embodiment of the present invention, etching the solidified layer to form a circuit in step 2) includes presetting a circuit structure and inputting a control component, and the control component controls the laser according to the circuit structure to etch the solidified layer on the transparent substrate. Etch to form circuits.

According to an embodiment of the present invention, the etching includes forming cutting lines on the cured layer according to the circuit structure, and stripping and cleaning the cured layer outside the circuit structure.

According to an embodiment of the present invention, the laser includes a pulsed laser with a wavelength in the ultraviolet to mid-infrared band, and the wavelength of the laser is in the range of 200-2000 nm, for example, 1064 nm.

Preferably, the power of the laser is 2-40W, for example, a near-infrared pulsed laser of 5W-30W or an ultraviolet laser of 2-8W.

Preferably, the cutting speed of the etching is set to 1-7 m/s, preferably 2-5 m/s.

According to an embodiment of the present invention, the cleaning of the solidified layer outside the circuit structure, for example, using high pressure air to blow the surface of the cut transparent substrate.

According to an embodiment of the present invention, after step 2), step 3) is further included: detecting whether the transparent substrate with circuit is qualified.

According to an embodiment of the present invention, detecting whether the transparent substrate with a circuit is qualified includes a): obtaining a circuit pattern on the surface of the transparent substrate, comparing the circuit image with a preset circuit structure, and judging whether there is a disconnected area and/or areas that do not conform, if so, the circuit structure is unqualified, otherwise, the circuit structure is qualified.

According to an embodiment of the present invention, the non-conforming area includes whether the burr on the edge of the circuit structure is greater than 15% of the circuit set width, and whether the circuit structure has a width smaller than the set width.

According to an embodiment of the present invention, after judging that the circuit structure is qualified, the following step b) is further included: conducting power-on and short-circuit detection on the circuit structure. If the detection passes, the transparent substrate with the circuit is qualified, otherwise, it is discarded.

According to an embodiment of the present invention, after judging that the circuit structure is qualified, the following steps are further included: detecting whether the electrical parameters of the circuit structure are consistent with preset values, if yes, it is a qualified product, otherwise it is discarded.

According to an embodiment of the present invention, after judging that the transparent substrate with circuits is unqualified, it further includes a step of correcting the circuit structure on the unqualified transparent substrate with circuits, for example, the burr on the edge of the circuit structure is larger than that of the circuit Correct the circuit configuration with a set width of 15%.

According to an embodiment of the present invention, the correction includes: emitting a laser from the side facing away from the cured layer to the transparent substrate to re-etch the unqualified areas on the circuit.

According to an embodiment of the present invention, after correcting the circuit, it further includes detecting whether the corrected circuit structure is qualified, and the detecting step is the same as step 3).

The present invention also provides a transparent substrate with a circuit, which is prepared by the above-mentioned method.

The present invention also provides the use of the above-mentioned transparent substrate with circuit in electronic products, such as the use in flexible screens and wearable electronics.

beneficial effect

By combining with the laser etching technology, the invention adopts a high-speed galvanometer to control the laser beam, and passes through the transparent substrate from the back to selectively peel off the conductive layer cured on the transparent substrate, leaving the required circuit lines. After passing the visual inspection, secondary correction of the circuit line is carried out using laser to ensure the 100% yield of the line.

Compared with the traditional process, the method of the present invention does not need any printing equipment or mask, the process is simple, the cost is low, the equipment dependence is low, the automation degree is high, and the yield is high, which is very suitable for mass production. The method of the invention still ensures the high light transmittance of the base material while preparing a good circuit.

Description of drawings

Fig. 1 is the schematic diagram of step b spraying conductive ink in the embodiment of the present invention;

2 is a schematic diagram of step d detecting whether the surface of the transparent substrate with a cured layer is defective in the embodiment of the present invention;

Fig. 3 is the schematic diagram of laser etching in step f in the embodiment of the present invention;

FIG. 4 is a schematic diagram of visual inspection in step g in an embodiment of the present invention.

Among them, 1-transparent substrate, 2-conductive ink, 3-print head, 4-cured layer, 5-imaging component, 6-position adjustment component, 7-display and/or alarm, 8-laser, 9-beam movement Control focusing mechanism, 10-circuit structure.

Detailed ways

The method and application of the present invention will be described in further detail below with reference to specific embodiments. It should be understood that the following examples are only for illustrating and explaining the present invention, and should not be construed as limiting the protection scope of the present invention. All technologies implemented based on the above content of the present invention are covered within the intended protection scope of the present invention.

Unless otherwise stated, the starting materials and reagents used in the following examples are commercially available or can be prepared by known methods.

Example 1 A device for printing circuits on transparent substrates

A device for printing a circuit on a transparent substrate, comprising a spraying mechanism, a laser processing mechanism and a visual inspection mechanism, the spraying mechanism includes a nozzle 3 for spraying a solution, the laser processing mechanism includes a control assembly and a laser, and the control assembly is used to control the laser According to the movement speed, mechanism power and movement trajectory, the laser 9 is used to emit the laser 8 to the transparent substrate 1 for circuit etching.

The visual inspection mechanism includes an imaging component 5, a recognition and judgment component and a feedback component. The imaging component 5 is connected with the recognition and judgment component. The imaging component 5 is used for imaging the component to be tested, and sends the image to the recognition and judgment component for recognition and judgment; the feedback component It is connected with the identification and judgment component for feedback of the judgment result. Preferably, the feedback component includes a display and/or an alarm 7, the display is used to display the judgment result, and the alarm is used to give an alarm when the detection result is abnormal.

Among them, the imaging component 5 includes a camera, such as a high-definition camera; the identification and judgment component includes a memory and a comparator, the memory is used to store the normal results, and the comparator traverses the image to determine whether there is an area on the image that is different from the normal result. If yes, it is judged that the bit is abnormal, otherwise, it is judged to be normal.

The laser processing mechanism also includes a cutting table and a position adjustment assembly 6, the position adjustment assembly 6 is arranged above the cutting table, the laser 9 and the imaging assembly 5 are connected with the position adjustment assembly 6, and the control assembly is connected with the position adjustment assembly 6 for controlling the position. The movement of the assembly 6 is adjusted, thereby adjusting the position of the laser 9 and the imaging assembly 5 .

The spraying mechanism further includes an accommodating cavity, and the accommodating cavity is used for accommodating a solution to be sprayed, such as conductive ink.

The spraying mechanism further includes a controller for adjusting the spraying speed of the spray head, and also, for example, adjusting the height of the spray head.

The laser processing mechanism includes any laser processing system with laser trajectory writing function, laser beam focusing function, and laser beam position control function such as laser marking machine and laser marking machine.

In actual use, the laser can be selected from common lasers on the market, such as fiber lasers and solid-state lasers. Solid-state lasers are used in the following embodiments, and the laser light emitted by the laser can be pulsed lasers with wavelengths in the ultraviolet to mid-infrared band.

Embodiment 2 A method of printing a circuit on a transparent substrate using the equipment of Embodiment 1

A method of printing a circuit on a transparent substrate, comprising the steps of:

Step a. Pretreating the transparent substrate 1 to be printed circuit: Use ethanol or acetone to clean both sides of the transparent substrate 1 to remove dust, oil and other stains, so as to improve the adhesion of the circuit layer.

Step b. Evenly spray the conductive ink on the surface of the transparent substrate 1, using the existing spraying equipment, the spraying conditions are as follows: the minimum ink droplet is 3.5pl, the number of nozzles is greater than 1000, the humidity of the working environment is 40-60%, the conductive ink after spraying The thickness of the film structure formed by the ink is less than 1 micron.

Step c. The transparent substrate 1 after spraying the conductive ink is transferred to a constant temperature oven and heated at a constant temperature of 150 degrees Celsius for 20 minutes until the conductive ink is cured on the surface of the transparent substrate to form a cured layer 4, and a transparent substrate with a cured layer 4 is obtained. Substrate 1.

Step d. Detect whether the surface of the transparent substrate 1 with the cured layer 4 is defective. Defects refer to bubbles with a diameter greater than 20 microns and/or cracks with a length/width of more than 20 microns. If there are no defects, transfer to step e, otherwise , and discard the defective substrate.

Step e. Transfer the transparent substrate 1 with the cured layer 4 without defects on the surface to a laser processing system, and set the circuit shape and the desired stripping area in the laser processing system.

Step f. According to the set circuit shape and the desired peeling area, use a laser to selectively peel off the surface of the transparent substrate with the cured layer and remove the residue, and the unpeeled part is the circuit structure 10 .

Specifically, the laser is generally a near-infrared pulsed laser (low cost) with a power of 5W-15W, and an ultraviolet laser (higher cost) can also be used with a power of 2-8W, and the distance from the cured layer depends on the field lens used Focal length, usually the focal length is set to 100-165mm, and the cutting speed is set to 1-7m/s; high-pressure air can be used to purge after cutting.

Step g. First perform visual inspection on the circuit structure 10 left after stripping, and detect electrical parameters when necessary according to customer needs to determine whether the index is met, and if it meets the standard, it is qualified, otherwise, determine whether it is a correctable product, if it is. , go to step h.

Among them, the visual detection can be a camera and an image processing system driven by a robotic arm or a displacement mechanism. By comparing the image obtained by the camera with the set circuit, it is judged whether there is an inconsistent area or a disconnected area. Specifically, it is judged whether there is a The circuit is disconnected, whether the burr on the edge of the circuit is greater than 15% of the set width of the circuit, and whether the circuit has a width less than the set width. Among them, the circuit structure is disconnected or the width is too small, and the circuit structure needs to be discarded, and the burr is too large. The circuit structure can be re-corrected to be a correctable circuit structure.

Detecting electrical parameters, such as detecting whether the resistance value of the circuit reaches the preset value, if not, it is an unqualified product and needs to be discarded.

Step h. Use a laser to perform secondary correction on the correctable circuit structure 10 and remove residues.

Step i. Perform secondary energization and short-circuit detection on the corrected circuit structure 10, and the qualified ones can flow into the subsequent processing flow.

The transparent substrate 1 targeted by the present invention can be any transparent material with a low absorption coefficient for the laser used, such as K9 glass, quartz, sapphire, transparent polymer film, and the like.

The conductive ink in step b contains conductive particles, and the conductive particles can be one or more of nano-silver, nano-gold, nano-copper, nano-silver alloy or nano-copper alloy; the conductive ink can be viscous or non-viscous Yes, in this embodiment, it is nano-silver conductive ink with a viscosity of 50-200pa.s, the content of silver in the nano-silver conductive ink is 30-50wt%, and the spraying of the conductive ink refers to the viscous liquid spraying process.

The laser processing system in step e can be a laser marking machine, any laser processing system with a laser trajectory writing function, a laser beam focusing function, and a laser beam position control function, such as a laser marking machine.

Optionally, the qualified products in step i can flow into the subsequent processing flow, and the subsequent processing flow can be any application of circuits using a transparent substrate, such as light-emitting diode patches, multi-layer composite circuit printing, etc.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. a kind of equipment of printing circuit on transparent base material, comprises spraying mechanism and laser processing mechanism, it is characterized in that, described spraying mechanism comprises the nozzle that is used for spraying solution, and described laser processing mechanism comprises control assembly and laser, so The control component is used to control the movement speed, mechanism power and movement track of the laser, and the laser is used to emit laser light to the transparent substrate for circuit etching. Preferably, the device further includes a visual inspection mechanism, the visual inspection mechanism includes an imaging component and a recognition and judgment component, the imaging component and the recognition and judgment component are connected, and the imaging component is used for imaging the component to be tested, and converting the image It is sent to the identification and judgment component for identification and judgment. 2 . The device for printing a circuit on a transparent substrate according to claim 1 , wherein the visual detection mechanism further comprises a feedback component, the feedback component is connected to the identification and judgment component for feeding back the judgment result. 3 . Preferably, the identifying and judging component includes a memory and a comparator, the memory is used to store the normal result, the comparator traverses the image and judges whether there is an area on the image that is different from the normal result, and if so, judges The bit is abnormal, otherwise, it is judged as normal. Preferably, the laser processing mechanism further includes a cutting table and a position adjustment assembly, the position adjustment assembly is disposed above the cutting table, the laser and the imaging assembly are respectively disposed on the position adjustment assembly, and the control assembly is connected to the position adjustment assembly. The component connection is used to control the movement of the position adjustment component, and then adjust the position of the laser and the imaging component. 3 . The device for printing a circuit on a transparent substrate according to claim 1 or 2 , wherein the spraying mechanism further comprises an accommodating cavity, and the accommodating cavity is used for accommodating the solution to be sprayed. 4 . Preferably, the spraying mechanism further includes a controller for adjusting the spraying speed of the spraying head. Preferably, the laser processing mechanism includes any laser processing system such as a laser marking machine, a laser marking machine, etc., which has a laser trajectory writing function, a laser beam focusing function, and a laser beam position control function. 4. A method for printing a circuit on a transparent substrate using the equipment of any one of claims 1-3, characterized in that, comprising the following steps: 1) spraying conductive ink on the surface of the transparent substrate and drying to obtain a transparent substrate with a cured layer; 2) emitting a laser from the side facing away from the cured layer to the transparent substrate, and etching the cured layer to form a circuit to obtain a transparent substrate with a circuit structure. 5 . The method for printing a circuit on a transparent substrate according to claim 4 , wherein the transparent substrate is selected from a transparent material with a low laser absorption coefficient. 6 . Preferably, in step 2), the conductive ink includes conductive particles and a solvent, and the conductive particles include one, two or more of nano-silver, nano-gold, nano-copper, nano-silver alloy, and nano-copper alloy. Preferably, the content of silver in the nano-silver conductive ink is 30-50wt%, preferably the content of silver in the nano-silver conductive ink is 35-45wt%, further, the content of silver in the nano-silver conductive ink is 38-42wt% %. Preferably, the conductive ink is a viscous solution or a non-viscous solution. Preferably, the drying of the conductive ink in step 1) is performed under a constant temperature condition. Preferably, the temperature of the constant temperature is 140-180 degrees Celsius. Preferably, the drying time of the conductive ink is more than 15 minutes. 6. The method for printing a circuit on a transparent substrate according to claim 4 or 5, characterized in that: between step 1) and step 2), the following step is further included: detecting whether the transparent substrate with the cured layer is qualified. Preferably, detecting whether the transparent substrate with the cured layer is qualified includes: observing whether the surface of the cured layer is defective, preferably by observing and judging by a visual inspection mechanism. For example, the imaging component images the surface of the cured layer and then transmits it to the visual inspection mechanism, and the visual inspection mechanism analyzes and judges the image. When it is judged that the surface of the cured layer has defects, it will be The transparent substrate is discarded. Preferably, the defects comprise bubbles with a diameter greater than 20 microns and/or cracks with a length/width greater than 20 microns. 7. The method for printing a circuit on a transparent substrate according to claim 4 or 5, wherein: in step 2), etching the cured layer to form a circuit comprises: presetting a circuit structure and inputting a control component, the The control component controls the laser to etch the solidified layer on the transparent substrate according to the circuit structure to form a circuit. Preferably, the etching comprises forming cutting lines on the solidified layer according to the circuit structure, and stripping and cleaning the solidified layer other than the circuit structure. According to an embodiment of the present invention, the laser includes a pulsed laser with a wavelength in the ultraviolet to mid-infrared band, and the wavelength of the laser is in the range of 200-2000 nm. Preferably, the power of the laser is 2-40W. 8. The method for printing a circuit on a transparent substrate according to claim 4 or 5, characterized in that: after step 2), it further comprises step 3): detecting whether the transparent substrate with the circuit is qualified. Preferably, detecting whether the transparent substrate with the circuit is qualified includes a): obtaining a circuit pattern on the surface of the transparent substrate, comparing the circuit image with a preset circuit structure, and judging whether there is a disconnected area and/or a If there is a matching area, the circuit structure is unqualified; otherwise, the circuit structure is qualified. Preferably, the non-conforming area includes whether the burr on the edge of the circuit structure is greater than 15% of the circuit set width, and whether the circuit structure has a width smaller than the set width. Preferably, after judging that the circuit structure is qualified, the following step b) is further included: conducting a power-on and short-circuit detection on the circuit structure, if the detection passes, the transparent substrate with the circuit is qualified, otherwise, it is discarded. Preferably, after judging that the circuit structure is qualified, it further includes the following steps: detecting whether the electrical parameters of the circuit structure are consistent with the preset values, if yes, it is a qualified product, otherwise it is discarded. Preferably, after judging that the transparent substrate with the circuit is unqualified, the step of correcting the circuit structure on the unqualified transparent substrate with the circuit is also included. Preferably, laser light is emitted from the side facing away from the cured layer to the transparent substrate to re-etch the unqualified areas on the circuit. Preferably, after correcting the circuit, it also includes detecting whether the corrected circuit structure is qualified, and the detecting step is the same as step 3). 9. A transparent substrate with a circuit, which is prepared by the method of any one of claims 4-8. 10. A transparent substrate with a circuit prepared by the method of any one of claims 4-8 or the use of the transparent substrate with a circuit according to claim 9 in electronic products, for example in flexible screens, wearable electronics use in.

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