GB/T 23981.2 is the second part of the “Determination of the hiding power of paints and varnishes”, designed to specify the method of determining the hiding power of paints. The implementation of the standard replaces GB/T 1726-1979, and improves the technical standard and operability by increasing the scope, term definition, instrument and equipment requirements, test steps, calculation formulas and precision. The hiding power of paint is one of the important indicators of the construction performance of paint products. The purpose of this standard is to establish a method for determining the hiding power of paint.

GB/T 23981.2-2023: Determination of the hiding power of paints and varnishes – Part 2: black and white grid method – Interpretation

The covering ability of a coating product is crucial to its effect during construction. GB/T 23981.2 is a method for determining the covering power of paint. This standard determines the covering power of the color paint by the black and white grid method to assess the coating’s covering ability to the substrate color or color difference. The main purpose of revising GB/T 1726 to GB/T 23981.2 is to make the measurement method of hiding power more comprehensive and reasonable, and to promote the trade and technological development of coating products by standardizing the measurement process.

Content analysis:

This document is mainly applicable to the determination of the hiding power of the color paint, using the black and white grid method. Key points include terminology and definitions, material and instrumentation requirements, sample preparation and test environment control, test procedures, and presentation of results.

Terms and definitions:

hiding power: The ability of the coating to hide the color or color difference of the substrate.

paint: Paint containing pigment that forms an opaque dry film for protection, decoration, or special purposes.

Materials and equipment:

Including soft brush, glass plate, cup, balance, black and white grid glass plate, black and white grid sticker, camera obscula and so on.

Cup capacity, glass plate size, day bisection value, black and white grid specifications, etc., have clear requirements.

Test steps:

A method (brush coating method) and B method (spraying method) two test methods.

Method A includes sample test, result representation and result representation when adding diluent test.

Method B includes sample testing and result representation, involving coating spraying, drying and other steps.

GB/T 23981.2-2023: Determination of the hiding power of paints and varnishes – Part 2: black and white grid method – Interpretation

Precision and test report:

– Precision has not yet obtained the relevant data, the test report should include the identification of the tested product information, the method used, the test results and other content.

GB/T 23981.2 is a technical standard on the determination of the hiding power of color paint, and the black and white grid method is used to evaluate the hiding power of color paint. Through standardized testing of the covering properties of coatings, this standard helps to establish technical specifications for coating products, improve product quality, and promote trade and technological development of coating products.