1、 FORD LABORATORY TEST METHOD BI 101-02 Date Action Revisions 2001 03 13 Revised Editorial no technical change A. Cockman 1989 09 08 Printed copies are uncontrolled Page 1 of 2 Copyright 2001, Ford Global Technologies, Inc. MEASUREMENT OF CONTRAST RATIO OF PAINT DRY HIDING POWER Application This proc
2、edure is used to measure the contrast ratio, or dry hiding power, of production and maintenance paints. Contrast is the ability of that paint to reduce the contrast of a black and white surface to which it is applied and allowed to dry. Apparatus Required Colorimeter A “Colormaster differential colo
3、rimeter“, or equivalent, is used to measure the reflectance of the paint when applied over standard black and white surfaces. The instrument may be obtained from: Source: Meeco Instrument Manufacturing Co. Hatboro, PA U.S.A. Checkerboard The black and white checkerboard used in this test is a No. 5
4、ASTM checkerboard. The board is made up of black and white squares having standard reflectance values. Source: Leneta-Morest Div. P.O. Box 86 Ho-Ho-Kus, NJ 07423 U.S.A. Conditioning and Test Conditions All test values indicated herein are based on material conditioned in a controlled atmosphere of 2
5、3 +/- 2 C and 50 +/- 5 % relative humidity for not less than 24 h prior to testing and tested under the same conditions unless otherwise specified. FORD LABORATORY TEST METHOD BI 101-02 Page 2 of 2 Copyright 2001, Ford Global Technologies, Inc. Procedure 1. Cut a strip of checkerboard, three squares
6、 in width and five squares in length. Cut out and discard the center square. 2. Place the checkerboard over a clean steel panel and secure at upper and lower edges with masking tape. The section of the steel panel which is exposed to the cutout is used to check the thickness of the subsequently appl
7、ied paint film. 3. Reduce the paint sample to the proper spraying viscosity with the appropriate thinner as specified by the relevant Engineering Materials Specification. 4. Spray as specified in Ford Laboratory Test Method BI 103-02, Method “C“, or to the film thickness specified by the Engineering
8、 Materials Specification. 5. Bake as designated by the Engineering Materials Specification. 6. Place a strip of the painted checkerboard on the colorimeter, set for the green filter and measure the reflectance of the painted black square and then the white square. Evaluation Calculate and report the
9、 contrast ratio of the paint from the following formula: Black Reflectance = Contrast Ratio (Dry Hiding Power) White Reflectance Chemicals, materials, parts, and equipment referenced in this document must be used and handled properly. Each party is responsible for determining proper use and handling in its facilities.
