Determination for the solvent resistance of coatings by solvent rubs
1 Scope
This standard specifies a test method for determining the solvent resistance of single or composite coating systems of paints, varnishes, or related products by solvent rubs.
This test method is applicable to the determination for the solvent resistance of coatings (that undergo chemical reactions during curing) by solvent rubs.
This method includes Methods A and B. Method A is manual rub, and Method B is instrumental rub.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, subsequent amendments (excluding corrections) to, or revisions of, any of these publications do not apply to this standard. However, parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies.
GB/T 3186 Paints, varnishes and raw materials for paints and varnishes - Sampling (GB/T 3186-2006, ISO 15528:2000, IDT)
GB/T 9271 Paints and varnishes - Standard panels for testing (GB/T 9271-2008, ISO 1514:2004, MOD)
GB/T 13452.2 Paints and varnishes - Determination of film thickness (GB/T 13452.2-2008, ISO 2808:2007, IDT)
GB/T 20777 Paints and varnishes - Examination and preparation of samples for testing (GB/T 20777-2006, ISO 1513:1992, IDT)
3 Terms and definitions
For the purposes of this standard, the following term and definition apply:
3.1
double rub
complete back-and-forth rub on the surface of a coating with solvent-soaked absorbent cotton or other agreed materials
4 Principle
For coatings that undergo chemical reactions during curing, such as epoxy resin, alkyd resin and polyurethane resin coatings, the film will become more solvent-resistant after curing. The solvent resistance of the film may be determined by rubbing it with absorbent cotton soaked in suitable solvents or other agreed materials.
5 Sampling
Take a representative sample of the product to be tested, as described in GB/T 3186.
Examine and prepare the sample for testing, as specified in GB/T 20777.
6 Test plates and test environment
6.1 Substrates
Unless otherwise agreed, the substrates shall meet the requirements of GB/T 9271, with minimum dimensions of 70mm×150mm.
6.2 Preparation and coating
Unless otherwise agreed, each substrate shall be prepared according to the requirements of GB/T 9271, and then coated by the specified method with the product or system under test. At least 2 test plates shall be prepared for each specimen.
6.3 Drying and conditioning
The coated test plates shall be dried and cured under the specified conditions.
6.4 Conditioning and test temperature of specimens
Before the test, the test plates shall be conditioned for at least 1h at a temperature of (23±2)℃ and a relative humidity of (50±5)%; unless otherwise specified, the test shall be carried out at 18℃~27℃.
7 Test methods
Foreword I
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Sampling
6 Test plates and test environment
7 Test methods
8 Test report
