PCB

MAR Tin Strip TP is a two part system which is used for stripping tin or tin/lead resist from printed circuit boards. MAR Tin Strip TP consists of TP Part A which removes the electroplate tin to the intermetallic layer. TP Part B strips the thin uniform intermetallic layer leaving the copper surface etch free while providing an anti-tarnish film over the copper surface. The system is designed for a two chamber automated horizontal spray systems.

Advantages of the MAR Tin Strip Strip TP system:

• TS Part A strip the tin layer without etching the copper
• TS Part B strips the uniform intermetallic layer only.
• Copper etching is eliminated from varying thickness on the board
• Can be operated in a steady state using bleed and feed system
• There is no need of a rinse between TP Part A & B
• Leaves a clean copper surface with an anti-tarnish finish
• No heavy sludge allowing easy waste treated
• System is designed for a high metal loading of tin in TP Part A
• Provides a chemical clean copper surface for NICKEL/GOLD finishes

WARRANTY AND DISCLAIMER: This information is based on our experience and is, to the best of our knowledge, true and accurate. MAR-Tech Holdings Inc. gives no warranty, expressed or implied and the products are sold upon condition that the purchasers will make their own tests to determine the quality and suitability of the product. Any information or suggestions are given without warranty of any kind and the purchasers are solely responsible any loss arising from the use of such information.

SOLUTION MAKEUP

• Both TP Part A and TP Part B are ready to use products.

OPERATING PARAMETERS

CONTROL

The MAR Tin Strip TP system operates in a steady state for both the TP Part A and TP Part B. The use of an auto dosing unit is required to control the solution specific gravity especially in the TP Part A chamber. Based on the metal loading of 100 to 200 g/l of tin, the specific gravity of the TP Part A should be controlled between 1.25 – 1.35. The replenishment of TP Part B should be set at 25 – 35% of that of the feed rate of TP Part A.

EQUIPMENT

Most horizontal spray systems are constructed using stainless steel or titanium which is suitable material of both the TP Part A & Part B.

There should be no rinse between the first stage, TP Part A and the second stage, TP Part B. The use of effective pinch roller must be used to avoid or reduce the carry over of the TP Part A into the second chamber of the TP Part B.

ANALYSIS

MAR TP Part A

Equipment

1. 2 ml Pipette
2. 50 ml Erlenmeyer flask
3. 50 ml Burette

Reagents Required

• 1.0N Sodium Hydroxide standard solution
• Phenol Red indicator

Procedure:

• Pipette 2 ml sample of solution into a 250 ml Erlenmeyer flask.
• Add 100 – 150 ml distilled water
• Add 3 – 5 drops of Phenol Red Indicator
• Titrate with 1.0 N Sodium Hydroxide to red endpoint.
• Record a “T”

Calculation:

• “T” x 13.2 = % MAR Tin Strip TP Part A

For optimum operation, the TP Part A in the first chamber should be maintained above 80%.

MAR TP Part B

Equipment

1. 5 ml Pipette
2. 50 ml Erlenmeyer flask
3. 50 ml Burette

Reagents Required

• 1.0N Sodium Hydroxide standard solution
• Phenol Red indicator

Procedure:

• Pipette 5 ml sample of solution into a 250 ml Erlenmeyer flask.
• Add 100 – 150 ml distilled water
• Add 3 – 5 drops of Phenol Red Indicator
• Titrate with 1.0 N Sodium Hydroxide to red endpoint.
• Record a “T”

Calculation:

• “T” x 5.7 = % MAR Tin Strip TP Part B

For optimum operation, the TP Part B in the first chamber should be maintained above 85%.