GB/T 23981.2-2023: Paints and varnishes - Determination of hiding power - Part 2: Checkerboard method - Interpretation

GB/T 23981.2 is Part 2 of "Determination of Hiding Power of Paints and Varnishes", which aims to specify the method for measuring the hiding power of coatings. The implementation of this standard replaces GB/T 1726-1979 and improves technical standards and operability by adding scope, term definitions, instrument and equipment requirements, test steps, calculation formulas and precision modifications. The hiding power of paint is one of the important indicators of the construction performance of coating products. This standard aims to establish a method for measuring the hiding power of coatings.

The hiding ability of a coating product is critical to its effectiveness during application. GB/T 23981.2 is a method for measuring the hiding power of coatings. This standard measures the hiding power of colored paints through the black and white grid method to evaluate the coating's ability to cover the color or color difference of the substrate. 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 through standardized measurement processes.

Content analysis:

This document is mainly applicable to the determination of the hiding power of paints, using the black and white grid method. Key points include terms and definitions, material and instrumentation requirements, specimen preparation and test environment control, test procedures, and result presentation.

Terms and definitions:

• Hiding power: The ability of a coating to cover the color or color difference of the substrate.

• Paint: Paint containing pigments that can form an opaque dry paint film with protective, decorative or special functions.

Materials and equipment:

• Including soft-bristled paint brushes, glass plates, cups, scales, black and white grid glass plates, black and white grid stickers, camera obscura, etc.

• There are clear requirements for cup capacity, glass plate size, balance graduation value, black and white grid specifications, etc.

experiment procedure:

• There are two testing methods: Method A (brushing method) and Method B (spraying method).

• Method A includes sample testing, result expression and result expression when adding diluent for testing.

• Method B includes sample testing and result presentation, involving steps such as spraying and drying of paint.

Precision and test reports:

- Relevant data on precision have not yet been obtained. The test report should include information identifying the product under test, the method used, test results, etc.

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