GB/T 22888-2021Leather - Physical and mechanical tests - Determination of cold crack temperature of surface coatings (English PDF)

6.4 of the 2008 edition);

- Adjust the test report (see Clause 7; Clause 7 of the 2008 edition).

This Standard uses the redraft law to modify and adopt ISO 17233:2017

"Leather - Physical and mechanical tests - Determination of cold crack

temperature of surface coatings".

Compared with ISO 17233:2017, the structural adjustments of this Standard

are as follows:

- Delete "3 Terms and definitions". The subsequent clause-subclause

numbers are changed in turn (see Clause 3 of ISO 17233:2017);

- Combine 6.2 and 6.3 in ISO 17233:2017 into 5.2 (see 5.2).

The technical differences between this Standard and ISO 17233:2017 and their

reasons are as follows:

- As for the normative references, this Standard has made adjustments with

technical differences, to adapt to the technical conditions of China. The

adjustments are mainly reflected in Clause 2 "Normative references". The

specific adjustments are as follows:

 Replace ISO 2418 with GB/T 39364, which modifies and adopts the

international standard (see 5.1 and Clause 7);

 Replace ISO 2419 with QB/T 2707, which modifies and adopts the

international standard (see 4.4);

 Delete the reference to EN 15987 (see Clause 2 of ISO 17233:2017).

- Delete "3 Terms and definitions". There is no actual content. It does not

affect understanding and use (see Clause 3 of ISO 17233:2017).

- Modify the requirements for adhesive tape, to avoid ambiguity (see 4.6).

- Add the requirements for sampling at non-standard locations, to meet the

needs of daily testing (or sampling directly from shoes and clothing) (see

5.1).

- Modify the test result presentation method if "the surface coating does not

crack when tested at -30 °C", which is in line with China's custom and to

avoid repetition (see 6.8).

This Standard has made the following editorial changes:

- Modify the expression method of test temperature range (see 4.1 and 4.2);

- Add subclause numbers for sampling and sample preparation (see Clause

5);

- Modify the content of testing at the specific temperature in the note to 6.2

(see 6.2);

- Adjust the sorting of the contents in the test report (see Clause 7);

- Delete the subclause numbers of A.2~A.10 in Annex A (see Annex A of ISO

17233:2017).

Leather - Physical and mechanical tests -

Determination of cold crack temperature of surface

coatings

4.1 Cooled chamber; the internal height is >=500 mm; the internal width and

depth are both >=300 mm; with a rack or other support; the temperature control

range is -30 °C~5 °C; the temperature control accuracy is at least +/-2 °C. The

design of the chamber shall allow free circulation of air around the test piece

......