White Photoimageable Solder Resist Ink for PCB（LB-1900W）
LB-1900W is a series of photoimageable solder resist ink, which is also bi-component screen printing and UV contact exposure. The coated film processed by high temperature hardening will be provided with high insulation and high solder resistance, which is specially designed for LED monitor and aluminum PCB, and the feature is more suitable for precise circuit board.
A: Feature Introduction
Bluish White/Milky White
Major agent: 280±20PS, curing agent: 70±20PS,
proportion of major agent against curing agent: 3/1
Pencil hardness tester
3M adhesive tape
280℃×10s×2 times, no bubbles, no dropping
Major agent: 750g,
B: Operation Procedure
(1)Dilution and viscosity adjustment
To stir for 5-10 minutes till it’s well-proportioned. If the viscosity needs to be adjusted, 1-3% of the diluent can be added in. It’s recommended to use DBE diluent, butyl glycol(BCS).
To stand for 10-15 minutes after fully stirring, and then to process screen printing.
Either 36T or 43T is available for screen mesh
Thickness of printing ink: between 25-30um.
A：To print and cure each side separately:
The first side in hot air circulating oven: 75±5℃、15-20 minutes.
The second side in hot air circulating oven: 75±5℃、20-25 minutes.
B：To print and cure two sides at the same time.
Hot air circulating oven: 75±5℃、25-30 minutes.
7K UV contact exposure: 500-700mj/c㎡
21-step sensitivity guide: 9-12 steps covered.
Developing solution: (1±0.2%) of Na2CO3 Solution
Temperature of developing solution: 30±2℃
Developing time: 40-60 seconds
Washing pressure: 1.8~2.2kg/c㎡
Temperature: 150±5℃ Curing time: 60 minutes
Matters need attention：
1. This type of printing ink only applies to the process of immersion nickel-gold and tin spraying, not for immersion tin or immersion silver, it can not be produced by UV machine.
2. Parameters above are only for reference, the specific operation should be subject to samples.