source:Industry News release time:2021-09-13 Article author:sznbone Popular:pcb
Common circuit board quality problems and improvement measures in PCB solder mask process
In the PCB solder mask process, as smart as you may encounter various problems in the production of circuit boards, the common ones are as follows:
Problem: White spots in printing
Reason 1: The printed PCB board has white spots
Improvement measures: the thinner does not match, use the matched thinner [please use the company's supporting thinner]
Reason 2: The circuit board is dissolved in the sealing tape
Improvement measures: switch to white paper to seal the net
Problem: sticky film
Reason 1: The circuit board ink is not dried
Improvement measures: check the ink dryness
Reason 2: PCB vacuum is too strong
Improvement measures: check the vacuum system (can not add air guide)
Problem: Poor exposure
Reason 1: Poor vacuum
Improvement measures: check the vacuum system
Reason 2: PCB exposure energy is inappropriate
Improvement measures: adjust the appropriate exposure energy
Reason 3: PCB exposure machine temperature is too high
Improvement measures: check the temperature of the exposure machine (below 26°C)
Problem: the ink won't dry
pcb circuit board/circuit board screen printing room
pcb circuit board/circuit board screen printing room
Reason 1: The exhaust air of the circuit board oven is not good
Improvement measures: check the exhaust air condition of the oven
Reason 2: Reduce the amount of thinner
Improvement measures: increase diluent, fully dilute
Reason 3: The ink is too thick
Improvement measures: appropriately adjust the ink thickness
Reason 4: The thinner dries too slowly
Improvement measures: use matching thinner [please use the company's supporting thinner]
Reason 5: The oven temperature is not enough
Improvement measures: Determine whether the actual temperature of the oven reaches the required temperature of the product
Problem: The development is not clean
Reason 1: The storage time after printing is too long
Improvement measures: control the placement time within 24 hours
Reason 2: The ink runs out before development
Improvement measures: work in the darkroom before developing (the fluorescent lamp is wrapped in yellow paper)
Reason 3: Development time is too short
Improvement measures: extend the development time
Reason 4: Exposure energy is too high
Improvement measures: adjust the exposure energy
Reason 5: The circuit board ink is over-baked
Improvement measures: adjust the baking parameters, not to burn to death
Reason 6: Ink mixing is uneven
Improvement measures: stir the ink evenly before printing
Reason 7: Not enough developing potion
Improvement measures: check the concentration and temperature of the potion if the temperature is not enough
Reason 8: The thinner does not match
Improvement measures: use matching thinner [please use the company's supporting thinner]
Problem: Excessive development (corrosion test)
Reason 1: The concentration of the potion is too high and the temperature is too high
Improvement measures: reduce the concentration and temperature of the potion
Reason 2: Development time is too long
Improvement measures: shorten the development time
Reason 3: insufficient exposure energy
Improvement measures: increase exposure energy
Reason 4: The developing water pressure is too large
Improvement measures: lower the developing water pressure
Reason 5: Ink mixing is uneven
Improvement measures: stir the ink evenly before printing
Reason 6: The ink is not dried
Improvement measures: Adjust the baking parameters, see the question [The ink does not dry]
Problem: Green Oil Bridge Broken Bridge
Reason 1: Insufficient exposure energy
Improvement measures: increase exposure energy
Reason 2: The board is not handled properly
Improvement measures: check the treatment process
Reason 3: Too much pressure for developing and washing
Improvement measures: check the developing and washing pressure
Problem: Foaming on the tin
Circuit board solder mask text screen printing room
Circuit board solder mask text screen printing room
Reason 1: Excessive development
Improvement measures: improve the development parameters, see the problem [over development]
Reason 2: The pre-treatment of the board is not good, and the surface is oily and dusty
Improvement measures: do a good job of pre-processing the PCB board and keep the surface clean
Reason 3: insufficient exposure energy
Improvement measures: check the exposure energy and meet the ink usage requirements
Reason 4: Abnormal flux
Improvement measures: adjust flux
Reason 5: Insufficient post-baking
Improvement measures: baking process after inspection
Problem: Poor upper tin
Reason 1: The development is not clean
Improvement measures: improve several factors of poor development
Reason 2: Post-baking solvent contamination
Improvement measures: increase oven exhaust or machine cleaning before spraying tin
Problem: post-bake oil
Reason 1: There is no segmented baking
Improvement measures: segmented baking
Reason 2: PCB plug hole ink viscosity is not enough
Improvement measures: adjust the ink viscosity of the plug hole
Problem: ink matt
Reason 1: The thinner does not match
Improvement measures: use matching thinner [please use the company's supporting thinner]
Reason 2: Low exposure energy
Improvement measures: increase exposure energy
Reason 3: The circuit board is overdeveloped
Improvement measures: improve the development parameters, see the problem [over development]
Problem: Ink discoloration
Reason 1: Insufficient ink thickness
Improvement measures: increase ink thickness
Reason 2: Oxidation of circuit board substrate
Improvement measures: check the pre-treatment process
Reason 3: The post-baking temperature is too high
Improvement measures: the time is too long to check the baking parameters
Problem: Ink adhesion is not strong
Reason 1: The ink model is not suitable.
Improvement measures: use appropriate inks.
Reason 2: The ink model is not suitable.
Improvement measures: use appropriate inks.
Reason 3: The drying time and temperature are incorrect and the exhaust air volume during drying is too small.
Improvement measures: use the correct temperature and time, and increase the exhaust air volume.
Reason 4: The amount of additives is inappropriate or incorrect.
Improvement measures: adjust the dosage or switch to other additives.
Reason 5: The humidity is too high.
Improvement measures: improve air dryness.
Problem: Blocking the Internet
Reason 1: Drying is too fast.
Improvement measures: add slow drying agent.
Reason 2: The printing speed is too slow.
Improvement measures: increase the speed and slow down the drying agent.
Reason 3: PCB ink viscosity is too high.
Improvement measures: add ink lubricant or extra slow drying agent.
Reason 4: The thinner is not suitable.
Improvement measures: use designated thinners.
Problem: penetration, blur
Reason 1: The ink viscosity is too low.
Improvement measures: increase the concentration without adding diluent.
Reason 2: The printing pressure of the circuit board is too large.
Improvement measures: reduce pressure.
Reason 3: Bad squeegee.
Improvement measures: Replace or change the angle of the squeegee screen.
Reason 4: The distance between the screen and the printing surface is too large or too small.
Improvement measures: adjust the spacing.
Reason 5: The tension of the silk screen becomes smaller.
Improvement measures: Re-make a new screen version.
Read recommendations:
Laminate copper-based PCB after 4L (sample)
Six-layer Immersion Gold Board (BGA)
Popular recommended products
Computer card board (four layers)
2021-04-25Single copper base PCB
2021-04-27Six-layer Immersion Gold Board (BGA)
2021-04-27High frequency PCB
2021-04-27Network communication board (sixth floor)
2021-04-29Single-sided double-layer AL base PCB
2021-04-27High frequency PCB
2021-04-27Display board (six layers)
2021-04-27High frequency PCB
2021-04-27Mobile phone template (six layers)
2021-04-27Six-layer Immersion Gold Board (BGA)
2021-05-27High frequency PCB
2021-04-27Aluminum substrate (double-sided)
2021-04-27Silver oil perforated plate (double-sided)
2021-04-27Six-layer Immersion Gold Board (BGA)
2021-05-27Six-layer Immersion Gold Board (BGA)
2021-04-27Six-layer Immersion Gold Board (BGA)
2021-05-24Six-layer Immersion Gold Board (BGA)
2021-05-27Six-layer Immersion Gold Board (BGA)
2021-04-27Six-layer Immersion Gold Board (BGA)
2021-05-24Six-layer Immersion Gold Board (BGA)
2021-05-27Six-layer Immersion Gold Board (BGA)
2021-04-27Laminate copper-based PCB after 4L (sample)
2021-04-27Six-layer Immersion Gold Board (BGA)
2021-04-26SMT stickers
2021-05-27Six-layer Immersion Gold Board (BGA)
2021-04-26SMT stickers
2021-05-27Six-layer Immersion Gold Board (BGA)
2021-04-26Mobile phone board
2021-04-27DIP plugin
2021-05-27Six-layer Immersion Gold Board (BGA)
2021-04-26Six-layer Immersion Gold Board (BGA)
2021-04-26DIP plugin
2021-05-27Mobile phone board
2021-05-27Related Information
The relationship between PCB safety distance and voltage
2024-04-22SMT surface mount processing.Hybrid circuit board PCB
2024-04-15PCB enterprises should pay attention to SMT matters.Electronic components PCB
2024-04-03PCB - the core building block of electronic products.Automotive Electronics PCB
2024-03-25PCB - the bridge and link of the electronic world
2024-03-18How to define high-frequency and high-precision circuit boards.Industrial Electronics PCB
2024-03-11USB PCB interface layout and wiring requirements
2024-01-22Electrolytic capacitor PCB.Steps for using PCB pins
2024-01-15Automotive ElectronicWhat aspects should be considered when processing and manufacturing PCB boards?
2024-01-08Electrolytic capaciWhat is the difference between a gold-plated circuit board and a gold-plated one?
2023-12-25When grinding PCB boards, attention should be paid to.Oscillator (belonging to crystal) PCB
2023-12-18Industrial Electronics PCB!What precautions should be taken when copying and grinding PCB boards
2023-12-11Do you know who is more suitable for LED direct display, regarding the difference between PCB board
2023-12-05Aluminum electrolytic capacitor PCB.What are the standards for selecting PCB boards
2023-11-27Surface Mount Technology (SMT) Phase PCB
2023-11-20Oscillator (belonging to crystal) PCB.The main functions of PCB board
2023-11-13What is the difference between RO filter and PCB filter
2023-11-06Method for determining blind hole PCB board
2023-11-01Electronic Manufacturing Services PCB!What are the effects of PCB board color on performance?
2023-10-23Introduction to the Manufacturing Steps and Requirements of PCBA Test Stand
2023-10-16PCB version maturity stage.AOI circuit board price
2023-09-25How to maintain a PCB circuit board
2023-09-19Development Trend of Printed Circuit Board.Zener diode PCB Vendor
2023-09-14Common problems and cause analysis of PCB circuit board sampling.Zener diode PCB price
2023-09-08What are the issues that need to be understood in PCB circuit board design?IGBT module PCB factory
2023-09-08How to reduce the risk of bending and deformation in PCB circuit board production?Inverter PCB Produ
2023-08-16What are the three main factors that constitute welding defects in PCB circuit boards?Multilayer PCB
2023-08-16The structure of a glass teapot.LCD Module PCB factory
2023-08-11Glass teapot.Inverter PCB Processing
2023-08-11PCB online debugging
2023-08-08