Acid resistance of the hottest printing materials

Acid resistance of printing materials and printing inks

this standard specifies the methods for evaluating the acid resistance of printing

this standard is applicable to all printing process substrates, such as paper, paperboard, plastic and metal (metal foil and metal plate)

2 reference standard

the provisions contained in the following standards constitute provisions of this standard through reference in this standard. When the standard is published, the editions shown are valid. All standards will be revised. All parties using this standard should explore and use the possibility of the latest versions of the following standards

iso 105-a03:1993 Textiles - rapid color testing - Part A03: grey scale for evaluating color

3 definition

this standard uses the following definitions:

3.1 acid resistance of printed matter: the ability of printed matter to withstand specific acids of specific concentrations within a specified time

note 1: the printed matter has no obvious change in the specific acid under experimental conditions, so it can be determined that the printed matter is acid resistant to this acid

4 principle

press the printed matter between two filter papers soaked in a specific acid solution in advance

evaluate the acid resistance through the color change of the printed matter and the degree of color impregnation of the filter paper

note 2: the type, concentration and time of the acid used are not fixed, because the acid resistance is affected by the ink, the substrate itself, and the interaction between the ink and the substrate

5 instruments and reagents

5.1 white quantitative filter paper for experiment: chemical analysis grade, smooth and soft surface, filter paper strip size 60mm × 90mm。

5.2 reference prints and test prints

5.3 to produce acid for testing bio rubber materials based on renewable cash crop yinjiaoju

5.4 glass plate: 60mm × 90mm。

5.5 grey scale for evaluating color (see ISO 105-a03)

5.6 distilled water

5.7 1kg weight

5.8 oven: temperature control range (50 ± 2) ℃

6 test conditions

the test should be carried out at standard temperature

note 4: according to the operating conditions of ordinary laboratories, the test temperature can be set at 20 ℃, 23 ℃ or 27 ℃, which is selected according to the ambient temperature of printed matter

7 test procedure

completely immerse two test filter papers in the tested acid solution, and then remove the acid solution on the surface of the filter paper until there are no acid drops. Put one piece of filter paper on the glass plate, 20mm × Place a 50mm test print on this filter paper, cover the test print with a second filter paper, and place another glass plate on the top layer. Put the finished glass test plate into a sealed package or container, and press a 1kg weight on the glass plate

the test print is taken out after penetrating within the specified time (see table A1), and rinsed with distilled water until the pH of the rinsing solution is neutral. Put the test print into the oven and dry it at (50 ± 2) ℃ for 30 minutes

the filter paper is naturally dried in the air, and cannot be rinsed with water before the test

8 evaluation

compare the dried test print with the reference print, and test the filter paper. Evaluate the test results according to the following terms:

1) if the appearance of the test sample has obvious changes, there is no acid resistance

2) there is no obvious change in the appearance of the test print, but the filter paper is soaked and needs to be evaluated according to the degree. If the degree of impregnation reaches grade 4 of the gray scale (see ISO 105-a03), it can be determined that the printed matter is decolorized

9 test report

the test report should include the following contents

A) the application standard

b) acid for test

c) concentration of acid for test

d) room temperature and temperature of test solution

e) soaking time

f) test whether the color of the printed sample changes. If the color changes, record the degree of change. The color change caused by the substrate should be clearly marked

g) whether the filter paper in contact with the test sample is soaked by the experiment machine

h) clearly record the changes of prints during the whole test process

note 5: according to this standard, some printing materials do not have acid resistance. Although many prints are impregnated on filter paper, they are still satisfactory in practical application. The degree of staining was evaluated by comparing it with the gray scale

Appendix A (prompted appendix)

recommended acid solution

Table A1 is the acid commonly used to test the acid resistance of printing materials, its concentration and soaking time

Table A1

sour milk acid lemon seconds acetic acid hydrochloric acid sulfuric acid

1) 2) 1) 2) 1) 2) 1) 2) 1) 2)

concentration 105515151

soaking time 1H 24h 1H 24h 30min 24h 10m can avoid the development of deterioration and failure in 24h 10min 24h

the substitute of this acid cheese and its products lemon juice pH <2 products

Note 6: these recommended acids The concentration and soaking time shall be applied only when other acids and service conditions are not involved

reprinted from: printed in Guangzhou