GB/T 15331-2020Test method for water vapor transmission rate of pressure-sensitive tapes (English PDF)

Foreword

This Standard was drafted in accordance with the rules given in GB/T 1.1-2009. This Standard replaces GB/T 15331-1994 "Test method for water vapor transmission of pressure-sensitive tapes". Compared with GB/T 15331-1994, the main technical differences in this Standard are as follows: - modified application scope of the standard (see Clause 1 of this Edition, Clause 1 of Edition 1994); - added normative references (see Clause 2 of this Edition); - modified terms and definitions (see 3.1,

3.2 of this Edition, Clause 2 of Edition 1994); - added that the test method is divided into test method for vertical water vapor transmission rate (see Clause 5 of this Edition) and test method for section water vapor transmission rate (see Clause 6 of this Edition); - modified principle (see 5.1,

6.1 of this Edition, Clause 3 of Edition 1994); - modified test box in instruments and equipment (see

5.2.1 of this Edition, Clause 4 of Edition 1994); - added test cover (see 5.2.2,

6.2.2 of this Edition); - added electronic balance requirements in instruments and equipment, division is 0.0001g (see

5.2.5 of this Edition); - added solvents required to use and requirements in instruments and equipment (see 5.2.7,

6.2.7 of this Edition); - added weights required to use and requirements in instruments and equipment (see 5.2.8,

6.2.8 of this Edition); - added edge sealing material in instruments and equipment (see

5.2.9 of this Edition); - added sampling requirements (see

5.3 of this Edition); - added requirements for standard test environment (see

5.4 of this Edition); - deleted weighing conditions (see Clause 6 of Edition 1994); - added preparation of test piece (see

5.6 of this Edition, Clause 5 of Edition 1994); Test method for water vapor transmission rate of pressure-sensitive tapes

1 Scope

GB/T 15331-2020 is the Chinese national standard on test method for water vapor transmission rate of pressure-sensitive tapes, in the field of rubber and plastic industries. The /T suffix marks it as a recommended standard: it is not compulsory by itself, but it becomes binding as soon as a contract, a tender or a customer specification calls it up - which in practice is how most foreign buyers meet it. It was issued on 19 November 2020 by the State Administration for Market Regulation; Standardization Administration of China, and has been in force since 1 October 2021. Classification: ICS 83.180, CCS G38. This page is published from the official record of the standard held by the Chinese standards administration: the identification, the dates, the classification and the issuing body are taken from there. The clause text, the tables and the numeric limits are in the document itself, which is delivered complete in English translation.

This Standard specifies test principle, instruments and equipment, preparation of test piece, test steps and result calculation for water vapor transmission rate of pressure-sensitive tapes. This Standard includes test methods for vertical water vapor transmission rate and section water vapor transmission rate. The test method for vertical water vapor transmission rate is applicable to single-sided or double-sided pressure- sensitive tape. The test method for section water vapor transmission rate is applicable to double-sided pressure-sensitive tape.

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

GB/T 4851-2014, Measurement of static shear adhesion for adhesive types

GB/T 22396, Terminology relating to pressure sensitive adhesive products

3 Terms and definitions

For the purposes of this document, the terms and definitions defined in GB/T 22396 as well as the followings apply.

3.1 vertical water vapor transmission rate; WVTRvertical under certain conditions, the mass per unit area of water vapor passing through the tape perpendicular to the direction of the adhesive surface per unit time NOTE: Usually it is expressed in grams per square meter day [g/(m2·d)].

3.2 section water vapor transmission rate; WVTRcross-section under certain conditions, the mass per unit length of water vapor permeating the tape in the sectional direction per unit time NOTE: Usually it is expressed in grams per square meter day [g/(m2·d)].

4 Classification

According to the different directions of water vapor passing through the pressure-sensitive tape, the test method for water vapor transmission rate of pressure-sensitive tape is divided into test method for vertical water vapor transmission rate (WVTRvertical) and test method for section water vapor transmission rate (WVTRcross-section).

5 Method One: Test of vertical water vapor

transmission rate (WVTRvertical)

5.1 Principle The pressure-sensitive tape is pasted on the test box with desiccant. Cover with a ring test cover to form a test piece. The test piece is exposed to an environment with controlled temperature and humidity. Weigh the mass of the test piece at regular intervals. When the weight gain of the test piece reaches equilibrium, use the mass increase per unit time and unit area of the tape to express the vertical water vapor transmission rate.

6 Method Two - Test of section water vapor

transmission rate (WVTRcross-section)