scope:

This standard has been designed and constructed with the intent of obtaining the maximum information about and confidence in the solder mask material under evaluation with the minimum of test redundancy. (See 6.1) This standard covers: - The evaluation and conformance of permanent solder mask material properties (Table 1, Column A). - The qualification of the solder mask/standard IPC-B-25A test board (Table 1, Column B). - The qualification assessment of the solder mask/production board process (Table 1, Column C). For purposes of this specification, the term "solder mask" is used herein when referring to any type of permanent polymer coating material applied prior to assembly, but excluding marking (legend) inks and temporary hole plugging material.

Purpose This standard enables a vendor to evaluate solder mask, and express the characteristics it possesses, when tested in a standard board system according to the test methods and conditions contained in this document. It also enables a printed board designer, manufacturer, and/or user to jointly qualify a production board process using the test methods and conditions contained in this document based on end use and environmental reliability requirements. Quality conformance of production boards shall be evaluated in accordance with IPC-6011 and IPC-6012.

The materials described herein are intended for use on printed boards in order to provide a solder mask to prevent solder bridging, and/or for the retardation of electromigration and other forms of conductive growth, and/or for the physical protection of the printed board.

This specification does not determine the compatibility of solder mask materials with post soldering products and processes. The determination of this compatibility is the responsibility of the board fabricator/board user. The test procedures specified herein may be useful tools to determine this compatibility.

Solder mask materials covered in the standard are not intended for use as a substitute for conformal coatings that are applied after assembly to cover components, component leads/terminations and solder connections.

This document lists the base requirements for solder mask and solder mask production board process. Additional requirements can be required as agreed upon between the solder mask vendor and the board fabricator, or between the board fabricator and end user.

This document assumes that the mask is processed and cured per the manufacturer's recommended process. The curing of the solder mask material that has been applied to printed boards shall be in accordance with those conditions specified by the solder mask vendor for that product or a qualified alternate method as agreed to between the board fabricator and the end user. When (other) alternate methods are used, the board fabricator has full responsibility for the performance of the solder mask.