Metal patch integrated forming method

Abstract

The invention belongs to the technical field of high-precision positioning antenna passive plate materials, and particularly relates to a metal patch integrated forming method which comprises the following steps: step 1, PPO material injection molding: selecting a DK value material for mold opening and injection molding; 2, after injection molding, a copper shaft sleeve is pre-installed in the hole; the copper shaft sleeve is made of T2 red copper tinned materials, the copper shaft sleeve is installed in a hole corresponding to the injection-molded plastic part, and preassembling is completed. According to the integrated forming method of the metal patch, an electroplating process is not adopted any more, and no pollution or influence is caused to the environment; and the pain point of high cost caused by multiple industrial varieties and small batch is solved. For numerous conventional injection molding boundary dimensions and thicknesses in the market, a male mold can be formed on the mold, an insert can be replaced at a middle hole position, and the appearance is not influenced due to the adoption of the metal patch, so that the mold cost is saved for numerous customers in the market.

Description

Technical Field

[0001] This invention relates to the field of passive board material technology for high-precision positioning antennas, and in particular to an integrated molding method for metal patches. Background Technology

[0002] Currently, in the field of passive board materials for high-precision positioning antennas, especially in applications requiring high-precision positioning antennas such as unmanned agricultural machinery, vehicles, and robots (e.g., lawnmowers, patrol vehicles), there are two main material technology routes. One is the use of high dielectric constant ceramic materials with silver paste application technology. This process is widely used in passive boards for small-sized (mostly 35*35mm and below) positioning antennas and has a good cost advantage, making it widely used in applications where positioning accuracy is not high, such as shared bicycles and buses. The other is the use of PPO material injection molding + POP (Plating on POP). The PPO (Polymer Optical Plastic) process technology involves injection molding PPO material with a dielectric constant of DK2~DK10 using a mold, followed by electroplating (nickel plating + laser engraving + copper plating + tin plating) + laser engraving. With the widespread application of intelligent driving and robotics, especially in high-precision positioning antennas, the PPO material + POP process technology offers advantages over ceramics, including less breakage, lighter weight, easier processing, lower cost for sizes larger than 40*40mm, higher dimensional accuracy of laser engraved circuits, better consistency, and no need for frequency adjustment. These advantages have led to its increasingly widespread use. Currently, in the field of high-precision positioning antennas, passive board solutions, ceramic solutions, and PPO material + POP solutions each have their own advantages and disadvantages, and each has its own application scenarios.

[0003] However, the PPO+POP process involves the electroplating industry, which requires significant capital investment in equipment, is a highly polluting industry, and has high overall operating costs for electroplating lines. The production process is lengthy, with prototyping typically taking 7-12 days and production delivery generally taking 2-4 weeks. Currently, in the niche market of passive microstrip antenna boards, the use of the PPO+POP process is concentrated in a few electroplating companies in Guangdong Province. There are many domestic companies that provide positioning antenna solutions, but as one of the core components, passive boards are scarce, have high operating costs, low unit prices and low overall value, high investment in electroplating equipment, high pollution, and a wide variety of products in small batches with extremely long production processes, which greatly limits the further development of the industry. Summary of the Invention

[0004] Based on the existing technical problems, this invention proposes an integrated molding method for metal patches.

[0005] The present invention proposes an integrated metal patch molding method, which includes the following steps: Step 1, PPO material injection molding, selecting a material with a DK value for mold opening and injection molding; Step 2: After injection molding, pre-install a copper bushing into the hole; the copper bushing is made of T2 tin-plated copper. Insert the copper bushing into the corresponding hole of the injection-molded plastic part to complete the pre-installation. Step 3: Selection of metal patch material. Select tin-plated copper sheet material with a thickness of 0.05~0.12mm on both sides of the PPO injection molding material. Step 4: Cutting the shape of the metal patch circuit. Laser cutting technology is used to shape the circuit of the tin-plated copper sheet material. Step 5: Select the appropriate double-sided tape solution. Choose a high-temperature resistant double-sided tape with a thickness of 30um to 50um and a temperature resistance of over 80℃. Apply the double-sided tape to the desired shape. Step Six: Apply double-sided tape to the corresponding metal pieces. The positions of the metallized holes should be designed to avoid gaps. First, attach one side of the metal piece with double-sided tape to the PPO plastic material, keeping the hole positions aligned. Then, attach the other metal piece with double-sided tape to the other side of the PPO plastic material. This will initially encapsulate the copper bushing inside the hole. Because there are gaps on the double-sided tape, at this point, the metal pieces on both sides of the PPO material and the copper bushing are only in contact with each other through the pressure of the double-sided tape, preparing for the next welding step. Step 7: Laser welding; Select a 100~500W welding laser machine with a spot diameter of less than Φ0.5mm, and perform circumferential laser welding on each hole where the copper bushing is installed on both sides. Step 8: Conductivity test. Select a DC low resistance tester with a test accuracy of 0.01 milliohms and a measurement range of 10 microohms to 2 ohms. Step 9: Anti-oxidation treatment. Spray or brush protective anti-fingerprint oil onto the metal patch areas, including the soldered areas, on both sides of the product.

[0006] Preferably, in step one, the material selected is Polyvent's DK6 material, model ET7600-8048 RSNC001.

[0007] Preferably, in step two, the copper bushing is selected with an inner diameter of Φ3±0.02mm, an outer diameter of Φ3.5mm±0.02mm, and a wall thickness of 0.25mm, wherein the inner diameter matching the hole after injection molding is Φ3.56±0.02mm.

[0008] Preferably, the length of the copper bushing is 0.15±0.05mm longer than the total thickness of the injection-molded plastic part plus the thickness of the double-sided adhesive on both sides.

[0009] Preferably, in step three, the surface of the tin-plated copper sheet is plated with 2-3 μm of tin.

[0010] Preferably, a 1000W laser cutting machine with an accuracy of ±0.05mm is selected in step four.

[0011] Preferably, in step five, a 300-500W laser engraving machine is selected, with a hole clearance design of 0.5mm-1mm.

[0012] Preferably, in step six, when attaching the patch, a simple positioning fixture is made by using positioning pins with a diameter of Φ2.85~2.9 mm and a length of 7~10 mm, which are directly inserted into the three metallized holes of the product as a simple positioning fixture.

[0013] Preferably, in step seven, the pulse width of the welding laser machine is 1.5~3ms, the current is 130~150A, and the frequency is 8~15MHz.

[0014] The beneficial effects of this invention are as follows: 1. Electroplating is no longer used, resulting in no environmental pollution or impact; it addresses the pain point of high costs caused by a wide variety of products and small batches in the industry. For many common injection molded shapes and thicknesses on the market, a generic mold can be opened, and inserts can be made in the central holes for replacement. Because metal patches are used, the appearance is not affected, thus eliminating mold costs for many customers in this market. Subsequent processes such as laser cutting of circuits and double-sided tape, and assembly processes have no requirements on order volume, directly solving the industry's pain points and preventing high costs or loss of price competitiveness due to a wide variety of products and small batches.

[0015] 2. Significantly lowers the industry entry barrier, eliminating the need for large-scale equipment investment in electroplating lines, resulting in a substantial reduction in investment amount. Compared to the investment in electroplating lines, the investment amount is less than 20% of that in electroplating line equipment; Low operating costs: There are no operating costs required for electroplating lines, including large site rental (often requiring professional electroplating parks), electricity, labor, and maintenance.

[0016] 3. Significantly Reduces Product Material Preparation and Obsolete Risks: In this industry, this is a very significant cost, and often carries considerable risk. Electroplating lines for a single product typically require a certain batch size to avoid frequent line changes. Since product wall thicknesses are often 4-8mm, injection molding cycles are usually quite long; a single order of several thousand units, especially if it involves stacked layers, can take up to a week to complete. Furthermore, it's difficult to immediately set up injection molding machines upon receiving an order. To slightly improve delivery times, companies often need to prepare materials based on customer needs, leading to inventory buildup and obsolete risk. However, the MIP (Made-in-Place) technology solution of this invention eliminates the need to consider the batch production requirements of the electroplating line. While injection molding begins, the antenna metal sheet circuit cutting and double-sided adhesive molding processes can start in parallel, with subsequent processes continuing immediately. This eliminates the need for risky material preparation, significantly reducing inventory, production cycles, and material preparation risks.

[0017] 4. Product sampling cycle: It only takes 3-5 days to complete the entire process, compared to 7-12 days in the electroplating industry, representing a significant speedup. Mass production product delivery cycle: It has also been reduced from 2-4 weeks in the electroplating industry to 5-7 days. Enhanced conductivity: Since the conductivity of copper is comparable to that of pure copper, the copper plating thickness in the POP electroplating industry is 30-35um. However, using surface mount technology, the thickness can be easily increased as needed. Considering cost factors, a thickness of 0.05-0.12mm is recommended. Using copper bushings made of the same material and then achieving metal integration through mechanical and physical welding solves the problem of contact resistance, thereby achieving a lower resistance than traditional electroplating and enhancing conductivity. Attached Figure Description

[0018] Figure 1 This is a flowchart illustrating a method for integral molding of metal patches. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0020] Example 1 Reference Figure 1 A method for integral molding of metal patches includes the following steps: Step 1, injection molding of PPO material, selecting DK value material for mold opening and injection molding; in Step 1, the material selected is PolyOne's DK6 material, model ET7600-8048 RS NC001.

[0021] Step 2: After injection molding, a copper bushing is pre-installed into the hole. The copper bushing is made of T2 tin-plated copper. The copper bushing is inserted into the corresponding hole of the injection-molded plastic part to complete the pre-installation. In Step 2, the copper bushing has an inner diameter of Φ3±0.02mm, an outer diameter of Φ3.5mm±0.02mm, and a wall thickness of 0.25mm. The inner diameter of the hole after injection molding is Φ3.56±0.02mm. The length of the copper bushing is 0.15±0.05mm longer than the total thickness of the injection-molded plastic part plus the thickness of the double-sided adhesive on both sides.

[0022] Step 3: Selection of metal patch material. Select tin-plated copper sheet material with a thickness of 0.05~0.12mm on both sides of the PPO injection molding material; the surface of the tin-plated copper sheet material in Step 3 is tin-plated with 2~3um.

[0023] Step 4: Cutting the shape of the metal patch circuit. Laser cutting technology is used to shape the circuit of the tin-plated copper sheet material. A 1000W laser cutting machine with an accuracy of ±0.05mm is selected in step 4.

[0024] Step 5: Select a double-sided tape solution. Choose a 30um~50um high-temperature resistant double-sided tape with a temperature resistance of over 80℃. Use the double-sided tape to conform to the shape. In step 5, select a 300~500W laser engraving machine with a hole clearance design of 0.5mm~1mm.

[0025] Step Six: Apply double-sided tape to the corresponding metal pieces. The locations of the metallized holes should be designed with clearance. First, attach one side of the metal piece with double-sided tape to the PPO plastic material, ensuring the holes are aligned. Then, attach the other metal piece with double-sided tape to the other side of the PPO plastic material. This will initially encapsulate the copper bushing within the hole. Because the double-sided tape leaves clearance, the metal pieces on both sides of the PPO material and the copper bushing are only in contact through the pressure of the tape, preparing for the next welding step. During the patch application in Step Six, create a simple positioning fixture using Φ2.85~2.9mm positioning pins, 7~10mm in length, directly inserted into the three metallized holes of the product as a simple positioning fixture.

[0026] Step 7: Laser welding; Select a 100~500W welding laser machine with a spot diameter of less than Φ0.5mm, and perform circumferential laser welding on each hole for the copper bushing to be installed on both sides; In step 7, the pulse width of the welding laser machine is 1.5~3ms, the current is 130~150A, and the frequency is 8~15MHz.

[0027] Step 8: Conductivity test. Select a DC low resistance tester with a test accuracy of 0.01 milliohms and a measurement range of 10 microohms to 2 ohms.

[0028] Step 9: Anti-oxidation treatment. Spray or brush protective anti-fingerprint oil onto the metal patch areas, including the soldered areas, on both sides of the product.

[0029] Electroplating is no longer used, resulting in no environmental pollution or impact. It addresses the pain point of high costs caused by a wide variety of products and small batches in the industry. For many common injection molded shapes and thicknesses on the market, a generic mold can be created, with inserts used to replace the parts in the central holes. Since metal patches are used, the appearance is unaffected, thus eliminating mold costs for many customers in this market. Subsequent processes such as laser cutting of circuits and double-sided tape, and assembly processes have no requirements on order volume, directly solving industry pain points for many customers. This prevents high costs or a loss of price competitiveness caused by small batches in applications with a wide variety of products.

[0030] Significantly lowers the industry entry barrier, eliminating the need for large capital investment in electroplating lines, resulting in a substantial reduction in investment amount. Compared to the investment in electroplating lines, the investment amount is less than 20% of that in electroplating line equipment; low operating costs: there are no operating costs required for electroplating lines, including large site rental (which often requires a professional electroplating park), electricity, labor, and maintenance.

[0031] Significantly reducing product preparation and obsolescence risks: In this industry, this is a very significant cost, and often carries considerable risk. Electroplating lines for a single product typically require a certain batch size to avoid frequent line changes. Since product wall thickness is often 4-8mm, injection molding cycles are usually quite long; a single order of several thousand units, especially if it involves stacked layers, can take up to a week to complete. Furthermore, it's difficult to immediately set up injection molding machines upon receiving an order. To slightly improve delivery time, companies often need to prepare materials based on customer needs, leading to inventory buildup and obsolescence risks. However, the MIP (Made-in-Place) technology solution of this invention eliminates the need to consider the batch production requirements of the electroplating line. While injection molding begins, the antenna metal sheet circuit cutting and double-sided adhesive molding processes can start in parallel, with subsequent processes continuing immediately. This eliminates the need for risky material preparation, greatly reducing inventory, production cycles, and preparation risks.

[0032] Product prototyping cycle: Only 3-5 days to complete, compared to 7-12 days in the electroplating industry, representing a significant speedup; Mass production product delivery cycle: Also improved from 2-4 weeks in the electroplating industry to 5-7 days; Enhanced conductivity: Since the conductivity of copper is comparable to that of pure copper, the copper plating thickness in the POP electroplating industry is 30-35um. However, using surface mount technology, the thickness can be easily increased as needed. Considering cost factors, a thickness of 0.05-0.12mm is recommended. Using the same material for the copper bushing and achieving metal integration through mechanical and physical welding solves the problem of contact resistance, thus achieving a lower resistance than traditional electroplating and enhancing conductivity.

[0033] Example 2 Reference Figure 1 A method for integral molding of metal patches includes the following steps: Step 1, injection molding of PPO material, selecting DK value material for mold opening and injection molding; in Step 1, the material selected is PolyOne's DK6 material, model ET7600-8048 RS NC001.

[0034] Step 2: After injection molding, a copper bushing is pre-installed into the hole. The copper bushing is made of T2 tin-plated copper. The copper bushing is inserted into the corresponding hole of the injection-molded plastic part to complete the pre-installation. In Step 2, the copper bushing has an inner diameter of Φ3±0.02mm, an outer diameter of Φ3.5mm±0.02mm, and a wall thickness of 0.25mm. The wall thickness is to leave sufficient welding space. The inner diameter of the hole after injection molding is Φ3.56±0.02mm. The length of the copper bushing is 0.15±0.05mm longer than the sum of the thickness of the injection-molded plastic part and the thickness of the adhesive on both sides. This ensures that the metal sheets on both sides maintain a proper interference contact after they are attached, which helps the subsequent welding process to proceed smoothly.

[0035] Step 3: Selection of metal patch material. Select 0.08mm thick tin-plated copper sheet material on both sides of the PPO injection molding material; the surface of the tin-plated copper sheet material in Step 3 is tin-plated by 2~3um.

[0036] Step 4: Cutting the shape of the metal patch circuit. Laser cutting technology is used to shape the circuit of the tin-plated copper sheet material. A 1000W laser cutting machine with an accuracy of ±0.05mm is selected in step 4.

[0037] Step 5: Select a double-sided adhesive solution, choosing a 30µm~50µm high-temperature resistant double-sided adhesive with a temperature resistance above 80℃. Use the double-sided adhesive for prototyping. In step 5, select a 300~500W laser engraving machine with a 0.7mm clearance design at the hole positions. This clearance is for subsequent welding processes; the metallized hole perimeter needs to be welded to the copper bushing. A laser engraving machine can be used for prototyping with double-sided adhesive, and after mass production, a die-cutting mold can be used for slicing, offering a cost advantage.

[0038] Step Six: Apply double-sided tape to the corresponding metal pieces. The locations of the metallized holes should be designed with clearance. First, attach one side of the metal piece with double-sided tape to the PPO plastic material, ensuring the holes are aligned. Then, attach the other metal piece with double-sided tape to the other side of the PPO plastic material. This will initially encapsulate the copper bushing within the hole. Because the double-sided tape leaves clearance, the metal pieces on both sides of the PPO material and the copper bushing are only in contact through the pressure of the tape, preparing for the next welding step. During the patch application in Step Six, create a simple positioning fixture using Φ2.85~2.9mm positioning pins, 7~10mm in length, directly inserted into the three metallized holes of the product as a simple positioning fixture.

[0039] Step 7: Laser Welding; Select a 300W welding laser machine with a spot diameter of less than Φ0.3mm. Perform circumferential laser welding on each hole where the copper bushing is installed on both sides. The purpose is to ensure that the copper sheets on both sides of the plastic part can conduct smoothly, and the resistance at any point on the copper sheets on both sides should be less than 3 milliohms. In Step 7, the pulse width of the welding laser machine is 2.5ms, the current is 140A, and the frequency is 10MHz.

[0040] Step 8: Conductivity test. Select a DC low resistance tester with a test accuracy of 0.01 milliohms and a measurement range of 10 microohms to 2 ohms. The final measured resistance of the two farthest points on both sides of the plastic part is 0.92 milliohms, which is much less than the internal standard of 3 milliohms for electroplated products.

[0041] Cross-cut adhesion test: The testing tools include a single-edged cutting tool, adhesive tape, and either NICHIBAN CT405AP-24 or 3M 610 adhesive tape. Test method: 1. Draw 10*10 1mm*1mm grids on the copper sheet using the cutting tool. Each grid line must penetrate to the double-sided adhesive on the back. If the test area is too small to provide sufficient space for grids, 90-degree crosses can be drawn on the test surface instead. 2. Apply adhesive tape to the grid area, ensuring the tape extends at least 20mm beyond the grid lines. Press the tape with a mobile phone or other tool to ensure full contact with the copper sheet (removing any air bubbles). 3. Grasp one end of the tape and peel it off very quickly within 1 second, perpendicular to the test surface. Test result: 4B Pass.

[0042] Alcohol Resistance Test: The testing tool used is an abrasion tester: indenter diameter φ10mm, load 1.0kg; alcohol: concentration ≥95%; cloth: 8 layers of medical gauze; test method: 1. Attach 8 layers of medical gauze to the indenter at the bottom of the testing machine. 2. Drip 0.5ml of alcohol onto the gauze. 3. Fix the test sample under the indenter, add weights above it, and the total downward force on the packaging gauze is 9.8N±0.05N (approximately 1kgf). 4. Set the stroke to 30mm, speed to 30mm / s, and start the test. Wipe the product surface back and forth with the gauze, one round trip every 2 seconds, until the specified number of test cycles is reached. 5. Check the test surface after a total of 100 cycles. Test result: The tested surface has no defects and is qualified.

[0043] RCA Abrasion Resistance Test: Test tools used: 1. Paper tape abrasion tester: indenter load adjusted to 175gf; 2. Paper tape type: NORMAN special paper tape (11 / 16 Inch Wide * 6); 3. Test environment: room temperature with 40%–60% humidity; 4. Paper tape storage environment: temperature 24±2℃, humidity 40%±5%; 5. Paper tape not used for more than 4 hours should be immediately stored in a drying oven. Test method: 1. Before testing, check for any abnormalities in appearance and set the abrasion tester to continuous rotation operation. 2. Adjust the horizontal arm load so that the test endpoint is subjected to a downward force of 175gf. 3. Attach the paper tape to the front and rear turntables and adjust the paper tape's path so that the test end washer presses on the paper tape (the inner surface of the paper tape contacts the product; do not place it backwards). 4. Adjust the position of the cross arm and fix the test sample securely (the test area of ​​the sample must not be suspended in the air; the bottom must be supported by a solid object), ensuring that the force of the cross arm acts vertically downwards on the test surface. 5. Zero the counter and start the test until the specified number of friction revolutions is reached. Test result: The copper sheet is not worn through; it is qualified.

[0044] Neutral Salt Spray Test: Test tools used: 1. Salt spray tester. 2. NaCl%: 5% (pH 6.5~7.2). 3. Adhesive tape: NICHIBAN CT405AP-24 or 3M 610. Test method: 1. Before testing, check the appearance of the sample for any abnormalities such as discoloration, cracks, or peeling, and wipe the paint surface clean with a lint-free cloth. 2. Place the test sample with one half facing up and the other half facing down at a 60-degree angle to the horizontal plane into the slot in the salt spray tester. Close the test chamber door and set the spray parameters. A single test cycle includes: 24 hours of salt spraying at 35±2℃ and humidity >85%. 3. Take one sample from each side and place them in a greenhouse environment for 24 hours, then check the test surface. 4. Place the other two samples in an environment of 40℃ and 95% humidity for 16 hours, then allow them to return to room temperature for 2 hours, and check the test surface. 5. Perform an adhesion test on the test surface using the "adhesive tape method". Test results: The resistance and conductivity are unaffected, and the test is successful.

[0045] Temperature Shock Test: Test tools used: 1. High and low temperature chamber. 2. Adhesive tape: NICHIBAN CT405AP-24 or 3M 610. Test method: 1. Before testing, check the product appearance for discoloration, bubbling, cracks, peeling, and other defects, and wipe the sample surface clean with a lint-free cloth. 2. Place the product in the thermal shock test chamber, and the chamber temperature will immediately drop to -40℃ for 1 hour. 3. Within 5 minutes, the product will rise into the hot chamber and be maintained at 80℃ for 1 hour. 4. Within 5 minutes, the product will descend into the cold chamber. 5. Repeat the above cycle 24 times. 6. Remove the product and allow it to cool and recover at room temperature for 2 hours, then observe the product appearance. 7. Perform an adhesion test on the test surface using the "tape method". Test results: No obvious cracking, delamination, deformation, or other defects; qualified.

[0046] High Temperature Test: Test tools used: 1. High and low temperature chamber. 2. Adhesive tape: NICHIBAN CT405AP-24 or 3M 610. Test method: 1. Before testing, inspect the product appearance for discoloration, bubbling, cracks, and peeling defects, and wipe the sample surface clean with a lint-free cloth. 2. Place the sample in the oven, set the temperature to 85℃ (humidity ≤10%), and the duration to 48 hours. 3. After baking, remove the sample and allow it to recover at room temperature for 2 hours, then observe the sample surface. 4. Perform an adhesion test on the test surface using the "adhesive tape method". Test results: Under standard light source, visual inspection at a distance of approximately 30cm showed no obvious deformation, delamination, or peeling defects, indicating it is qualified.

[0047] Constant Temperature and Humidity Test: Test tools used: 1. Constant temperature and humidity chamber. 2. Adhesive tape: NICHIBAN CT405AP-24 or 3M 610. Test method: 1. Before testing, check the product appearance for discoloration, bubbles, cracks, peeling, or other defects, and wipe the sample surface clean with a lint-free cloth. 2. Place the sample in the constant temperature and humidity chamber, set the temperature to 60℃, humidity to 90%, duration: 48 hours. 3. Perform an adhesion test on the test surface using the "adhesive tape method". Test results: No obvious delamination, peeling, deformation, or other defects; qualified.

[0048] Sunlight Aging Test; The testing tool used is a solar radiation test chamber. Test Method: 1. Place the sample to be tested in the test chamber and conduct a 24-hour test cycle under simulated solar radiation and temperature. Specifically, under dry heat of 40℃, the solar radiation intensity is 1120W / ㎡ (340nm band irradiance is 0.55W / M2), maintained for 20 hours, then turn off the solar radiation source for 4 hours. One test cycle consists of 3 cycles. 2. After the test, wait for the sample to return to room temperature and confirm whether there are any new appearance defects (such as discoloration spots, bubbles, wrinkles, whitening, dirt, cracks, uneven color, etc.), and whether the appearance defects before the test have been significantly changed. 3. Wipe the sample clean and use a colorimeter to test the color difference between the irradiated and aged areas and the area covered by aluminum foil. Measure the color difference value between the two areas. 4. If the color difference test is OK, conduct an adhesion test. Test Result: Resistance and conductivity were not affected, qualified.

[0049] Step 9: Anti-oxidation treatment. Spray or brush protective anti-fingerprint oil onto the metal patch areas on both sides of the product, including the soldering areas. If there are pin holes on the surface that require soldering pins, the pin holes should be covered with round stickers, leaving space for the soldering pins.

[0050] At this point, the entire product's MIP (Metal In-Pack) technology process has been completed, replacing the electroplating part of the POP process. Subsequent processes such as printing solder resist ink, soldering PIN pins, and applying double-sided tape can remain consistent.

[0051] The metal patch process in the microstrip antenna industry is frequently discussed in antenna theory, often simply mentioning the use of copper sheets. However, in the actual development and application of high-precision positioning antennas, both cupronickel and brass have failed in verification, ultimately failing to meet resistance requirements. This niche industry lacks practical applications because effective development and solutions have not been found regarding the selection of conductive materials, circuit dimensional accuracy, and the continuity between the emitting surface and the ground plane. Furthermore, due to the industry's niche nature and the broad range of process technologies involved—including mold making, injection molding, CNC machining, laser engraving, electroplating, printing, assembly, welding, and die-cutting—it receives little attention and lacks robust process development. This invention's MIP (Micro-In-Pack) technology solution is a national first in the high-precision positioning antenna passive board niche industry. Combining the industry's actual application needs, it creatively develops a process that can largely replace the POP (Point-on-Pack) process, possessing significant commercial application value.

[0052] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for integral molding of metal patches, characterized in that: The process includes the following steps: Step 1, PPO material injection molding, selecting a material with a DK value for mold opening and injection molding; Step 2: After injection molding, pre-install a copper bushing into the hole; the copper bushing is made of T2 tin-plated copper. Insert the copper bushing into the corresponding hole of the injection-molded plastic part to complete the pre-installation. Step 3: Selection of metal patch material. Select tin-plated copper sheet material with a thickness of 0.05~0.12mm on both sides of the PPO injection molding material. Step 4: Cutting the shape of the metal patch circuit. Laser cutting technology is used to shape the circuit of the tin-plated copper sheet material. Step 5: Select the appropriate double-sided tape solution. Choose a high-temperature resistant double-sided tape with a thickness of 30um to 50um and a temperature resistance of over 80℃. Apply the double-sided tape to the desired shape. Step Six: Apply double-sided tape to the corresponding metal pieces. The positions of the metallized holes should be designed to avoid gaps. First, attach one side of the metal piece with double-sided tape to the PPO plastic material, keeping the hole positions aligned. Then, attach the other metal piece with double-sided tape to the other side of the PPO plastic material. This will initially encapsulate the copper bushing inside the hole. Because there are gaps on the double-sided tape, at this point, the metal pieces on both sides of the PPO material and the copper bushing are only in contact with each other through the pressure of the double-sided tape, preparing for the next welding step. Step 7: Laser welding; Select a 100~500W welding laser machine with a spot diameter of less than Φ0.5mm, and perform circumferential laser welding on each hole where the copper bushing is installed on both sides. Step 8: Conductivity test. Select a DC low resistance tester with a test accuracy of 0.01 milliohms and a measurement range of 10 microohms to 2 ohms. Step 9: Anti-oxidation treatment. Spray or brush protective anti-fingerprint oil onto the metal patch areas, including the soldered areas, on both sides of the product.

2. The method for integral molding of metal patches according to claim 1, characterized in that: In step one, the material selected is PolyOne's DK6 material, model ET7600-8048 RS NC001.

3. The method for integral molding of metal patches according to claim 1, characterized in that: In step two, the copper bushing is selected with an inner diameter of Φ3±0.02mm, an outer diameter of Φ3.5mm±0.02mm, and a wall thickness of 0.25mm. The inner diameter that matches the hole after injection molding is Φ3.56±0.02mm.

4. The method for integral molding of metal patches according to claim 1, characterized in that: The length of the copper bushing is 0.15±0.05mm longer than the sum of the thickness of the injection-molded plastic part and the thickness of the double-sided adhesive on both sides.

5. The method for integral molding of metal patches according to claim 1, characterized in that: In step three, the surface of the tin-plated copper sheet material is plated with 2~3µm of tin.

6. The method for integral molding of metal patches according to claim 1, characterized in that: In step four, a 1000W laser cutting machine with an accuracy of ±0.05mm is selected.

7. The method for integral molding of metal patches according to claim 1, characterized in that: In step five, a 300-500W laser engraving machine is selected, and the hole clearance design is 0.5mm-1mm.

8. The method for integral molding of metal patches according to claim 1, characterized in that: In step six, when applying the patch, a simple positioning fixture is made by inserting positioning pins with a diameter of Φ2.85~2.9 mm and a length of 7~10 mm directly into the three metallized holes of the product as a simple positioning fixture.

9. The method for integral molding of metal patches according to claim 1, characterized in that: In step seven, the pulse width of the welding laser machine is 1.5~3ms, the current is 130~150A, and the frequency is 8~15MHz.

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