GB/T 18886-2019Textiles - Tests for colour fastness - Colour fastness to saliva (English PDF)

Foreword

This Standard is drafted in accordance with the rules given in GB/T 1.1-2009.

This Standard replaces GB/T 18886-2002 “Textiles - Tests for fastness - Colour fastness to saliva”. As compared with GB/T 18886-2002, the main changes are as follows:

- In “Normative references”, refer to GB/T 7568.1~7568.8 instead of the abolished GB 7564 ~ GB 7568 and GB 11404; ADD GB/T 6151, GB/T 6682, GB/T 13765, GB/T 32598, and GB/T 32616 (See Clause 2; Clause 2 of the 2002 edition).

- ADD the tolerance of intensity of pressure for the test devices (See 4.1).

- INCORPORATE “test solution preparation” into “Equipment and materials”;

modify the formula composition of artificial saliva; ADD the control index and preparation method of artificial saliva pH (See Clause 4; Clause 7 of the 2002 edition).

- In requirements for adjacent fabrics, ADD a note, that is: Other types of fibres may be used with reference to similar or alike fibres (See 4.4.2).

- ADD some equipment and materials (See 4.7~4.11).

- In “Operating procedures”, ADD a note, that is: A maximum of 10 combined samples can be placed simultaneously for each test device. Each sample is separated by a plate (11 pieces in total). If less than 10 samples, 11 plates are still used, to keep the pressure constant (See 6.1).

- ADD placement method of the combined sample (See 6.2).

- ADD an optional method of instrumental assessment of change in colour of the sample and staining of the adjacent fabric (See 6.4).

assessment result and the indication of assessment method to item c) (See Clause 7).

This Standard was proposed by China National Textile and Apparel Council.

This Standard shall be under the jurisdiction of National Technical Committee 209 on Textiles of Standardization Administration of China (SAC/TC 209).

Lufeng Weaving & Dyeing Co., Ltd., China National Accreditation Service for Conformity Assessment.

Main drafters of this Standard: Yang Xiaoxiao, Li Zhien, Fu Wei, Li Chun, Zhang Zhanqi, Xu Qiusheng, Huang Bixian, Chang Xiangzhen.

The previous editions of the standard replaced by this Standard were released as follows:

1 Scope

This Standard specifies the test method for the determination of the colour fastness to saliva of textiles.

This Standard applies to all kinds of textiles.

2 Normative references

The following documents are indispensable for the application of this document. For the dated references, only the editions with the dates indicated are applicable to this document. For the undated references, the latest edition (including all the amendments) are applicable to this document. GB/T 6682 Water for analytical laboratory use - Specification and test methods GB/T 7568.1 Textiles - Tests for colour fastness - Specification for wool adjacent fabric GB/T 7568.2 Textiles - Tests for colour fastness - Standard adjacent fabrics - Part 2: Cotton and viscose GB/T 7568.3 Textiles - Tests for colour fastness - Standard adjacent fabrics - Part 3: Polyamide GB/T 7568.4 Textiles - Tests for colour fastness - Specification for polyester adjacent fabric GB/T 7568.5 Textiles - Tests for colour fastness - Specification for acrylic adjacent fabric GB/T 7568.6 Textiles - Tests for colour fastness - Specification for silk adjacent fabric GB/T 7568.7 Textiles - Tests for colour fastness - Standard adjacent fabrics - Part 7: Multifibre GB/T 7568. […]

3 Principle

Attach the sample to the prescribed adjacent fabric. After being treated in artificial saliva, REMOVE the excess test solution; PLACE between two flat plates in the test device and apply a prescribed intensity of pressure; KEEP under a prescribed condition for a certain period of time. Then, DRY the sample and the adjacent fabric respectively; USE a grey scale or an instrument to assess the change in colour of the sample and the staining of the adjacent fabric.

4 Equipment and materials

5 Samples

5.1 For fabric samples, according to one of the following methods, prepare a sample:

5.2 For yarn or loose-fibre samples, the mass of yarn or loose fibre taken is approximately equal to half the total mass of the adjacent fabric. According to one of the following methods, prepare a combined sample:

adjacent fabrics. Sew along the four sides to form a combined sample.

6 Operating procedures

6.1 At room temperature, the combined sample is placed flat in a flat-bottomed container (4.10). Inject artificial saliva (4.3) to completely wet it at a bath ratio of 50:1. PLACE it at room temperature for 30 min. From time to time, PRESS down and stir, to ensure that the test solution can penetrate fully and evenly. TAKE the sample out; POUR off residual solution; USE a suitable method (such as two glass rods) to clip the excess test solution off the combined sample.

The combined sample is placed flat between two glass or acrylic acid resin plates (4.9) and placed in test devices (4.1) to be pressurized (12.5±0.9)kPa.

device. Each sample is separated by a plate (11 pieces in total). If less than 10 samples, 11 plates are still used, to keep the pressure constant.

6.2 PLACE the test devices (4.1) with the combined sample in the thermostat (4.2); HOLD at (37±2)°C for 4 h; PLACE the test devices (4.1) horizontal (Figure 1) or vertical (Figure 2).

6.3 TAKE the test devices out; unfold each combined sample so that the sample and the adjacent fabric are joined only at one short side; HANG the combined sample in air not exceeding 60 °C for drying.

6.4 USE a grey scale (4.5, 4.6) or an instrument (4.7) to assess the change in colour of the sample and the staining of the adjacent fabric.