JIS K 6259 Rubber, Vulcanized or Thermoplastic - Determination of Ozone Resistance

The standard “JIS K 6259 Rubber, vulcanized or thermoplastic - Determination of ozone resistance” developed by the Japanese Industrial Standards organization (JIS) consists of a series of standards organized under the same title:

• In the standard “JIS K 6259-1 Part 1: Static and dynamic stress test”, A procedure for the static ozone degradation test of vulcanized rubber and subsequently non-plastic rubber and for the ozone resistance by paint is described. This standard is essentially based on the standard "ISO 1431-1 Rubber, vulcanized or thermoplastic - Resistance to ozone cracking - Part 1: Static and dynamic tension test" developed by the International Organization for Standardization (ISO). This international standard describes procedures designed to predict the resistance to cracking of vulcanized or thermoplastic rubbers when exposed to air containing a specified concentration of ozone, under static or dynamic tensile stress, at a specified temperature and, if required, at a specified relative humidity, in the absence of direct light effects.

Visual observation or image analysis is used to assess the formation and growth of cracks. Changes in physical or chemical properties resulting from exposure can also be determined. Reference and alternative methods for determining ozone concentration are included in the ISO 1431-3 standard.

In performing this test, test pieces are exposed in a closed chamber to an atmosphere containing a constant concentration of ozone at a specified temperature and high or unspecified humidity, under static tensile stress, continuous dynamic stress, or alternating periods of dynamic and static stress. The test pieces are examined periodically for cracking.

Three alternative procedures for exposing and assessing cracking are described:

• The presence or absence of cracks is determined after exposure for a fixed period of time to a given static stress, dynamic stress, or a combination of dynamic and static stress. The presence or absence of cracks is determined by visual observation or image analysis. If necessary, an estimate of the degree of cracking is made. If necessary, physical or chemical properties are measured after exposure to determine the deterioration of the sample materials by comparison with the original parts.
• The time for the first appearance of cracks is determined at a given static stress, dynamic stress, or a combination of dynamic and static stresses.
• The threshold and limiting threshold stress are determined by visual observation and/or image analysis for any given exposure time (applicable only to static tensile stress tests).

Essentially, this standard is based on the standard “ISO 1431-3 Rubber, vulcanized or thermoplastics - Resistance to ozone cracking - Part 3: Reference and alternative methods for determining ozone concentration in laboratory test chambers” developed by the International Organization for Standardization (ISO). This international standard describes three methods for determining ozone concentration in laboratory test chambers:

• Method A UV absorption: This is the reference method and is used as a calibration tool for alternative methods B and C.
• Method B Instrumental techniques: B1 Electrochemical and B2 Chemiluminescence
• Method C Wet chemical techniques: Procedure I, Procedure II and Procedure III

An ozone/air mixture is sampled from the ozone exposure chamber and the ozone concentration is determined by the UV absorption reference method or alternative instrumental or chemical analysis methods calibrated against the UV absorption method.

Among the numerous tests, measurements, analyses and evaluation studies carried out for businesses in various sectors, our organization also provides testing services defined in the standard “JIS K 6259 Rubber, vulcanized or thermoplastic - Determination of ozone resistance” with its trained and expert staff and advanced technological equipment.