FPC black hole circuit board factory copper foil test and acceptance method
　　Qualified raw materials are very important for electronics manufacturers, so the inspection of copper foil, which is one of the main substrates of FPC black hole line manufacturers, is even more important. The quality test and acceptance methods are as follows, which are worthy of your collection and reference.
　　 Take and send the sample material 250mm wide and cut it to 250mm×480mm. The cut material is subjected to SPS→lamination→exposure→etching-DES to form the circuit required for the test (double-sided etching is single-sided).
1.1 Anti-peeling test: Cut the etched circuit sample to an appropriate length (3.2mm×20cm with glued copper; 1mm×20cm without glue) and pull out the copper foil by 1～3cm, and paste the PI surface of the copper foil substrate Fit it on a 90-degree flat fixture, the upper fixture clamps the copper foil and pulls the copper foil upward 90 degrees, the drawing speed is 50mm/min, and the average and most stable tension point is recorded. Bake at 150°C for 6 hours and ring measurement (temperature 60℃/humidity 90RH/72H) measure the tensile strength of the copper foil again to calculate the peel strength.
1.2 Thermal stress test: Cut the etched circuit sample into 3 pieces of 2.5cm×2.5cm size, remove the moisture by baking (150℃; 2hr), and immerse it in a tin bath (lead-free) at 288℃ for 10s Then take it out and check visually for blistering and peeling.
　　1.3 Flexural resistance test: Cut the etched circuit sample into 1mm (6 strips)×10cm for R0.8/Load500g (left and right swing 135 degrees) tortuosity test, read the MIT value and record it.
1.4 Chemical resistance test: Cut the etched circuit samples into 2.5cm×2.5cm three pieces, and place them in a solvent (10﹪2N HCL/10﹪2N NaOH/10﹪MEK/10﹪IPA) at room temperature for 5 minutes and observe Is there a phenomenon of potion attacking the line?
　　1.5 Buckling resistance test: Cut the etched circuit sample into 1mm (6 pieces)×10cm for R2/stroke 120 mm buckling test, read the MIT value and record it.
1.6 Insulation resistance test: Cut the etched circuit sample into a standard circuit, and bake it (50℃/24hr), set the voltage to DC 500V, connect two test points with a test pen, test time 60s, read Take the value and record it.
1.7 Secondary precipitation: cut the etched circuit sample into 1mm (18 lines)×10cm for pressing (temperature: 175℃; preheating time: 10S; molding time: 180S; pressure: 100kg/cm2), pressing After the pretreatment, the nickel plating test is carried out. After the nickel plating, use a 30-fold magnifying glass to observe whether there is copper exposed.
　　1.8 There is no need for secondary precipitation test for non-glue copper. Three sets of samples are taken for each test of the above test items.
2. Dimensional stability test: take the sample material 250mm wide, cut it into 250mm×280mm size and drill a hole with a diameter of 2.0mm in the four corners of the plate, measure the original size, and etch and remove the copper completely. Rinse with clean water, put it in an oven at 150℃ and bake for 30min. After standing at room temperature for 24hr, measure the size change, record the data, and calculate the size stability.
　　2.2 Dimensional stability judgment standard: non-glue copper ±0.1﹪; rubber copper ±0.15﹪, and the R value is qualified within ±0.05﹪.
3.0 Color card production: copper foil material requires the supplier to provide pure PI; a pure copper foil original color card will be sent as the raw material of the sample material (with plastic copper: copper + plastic + PI; non-glue copper: copper + PI). Make a color card in reverse. The double-sided board of the sample material is etched as a single-sided board. One side retains the circuit and the other side is the PI side. 8 copies of foil material color card.
　　4. Yield rate test: After the reliability test is completed, it is determined whether it meets the requirements of the factory. If it is OK, the yield test is performed, and NG does not need to be subjected to the yield test.
　　4.1 The R&D department applies for the production of test material numbers, and the business department places an order for test material numbers after receiving the R&D trial production notice, and the design department assists in the production of test material numbers.
4.2 According to the requirements of the R&D department, after the design of the new raw material sample is completed, the R&D department is notified to monitor at the key station (①after drilling ②after exposure and lamination ③after DES etching ④after CVL sandblasting ⑤after CVL pressing ⑥after processing and pressing ⑦After screen printing, ⑧After electroplating nickel and gold), measure the size expansion and shrinkage, and carry out quality tracking during the test.
　　4.3 After the test is completed, analyze the defective items according to the inspection, integrate the test results, and report to the relevant departments (environmental safety room, quality assurance department, manufacturing department, manufacturing department, design department, purchasing department).