ISO 2419:2012 pdf download.Leather一Physical and mechanical tests一Sample preparation and
conditioning
I Scope
This International Standard specifies the preparation of leather for physical and mechanical testing together
with standard atmospheres for conditioning and testing. It is applicable to all types of dry leather.
2 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
2.1 atmosphere
ambient conditions defined by the parameters temperature and relative humidity
2.2 standard atmosphere
atmosphere maintained within prescribed tolerances, in which a sample is kept for a given period of time before being subjected to testing
2.3 conditioning
operation designed to bring a sample into a specified condition in relation to temperature and relative humidity by keeping it for a given period of time in the standard atmosphere with free access of moving air to all surfaces
3 Standard atmospheres
3.1 Reference standard atmosphere
The reference standard atmosphere shall have a temperature of 23,0 °C and a relative humidity of 50,0 %.
3.2 Alternative standard atmospheres
3.2.1 General
Alternative, but not equivalent, atmospheres may be used only if the parties involved agree on their use. In case of dispute, the reference standard atmosphere shall be used.
3.2.2 Specific standard atmosphere
The alternative specific standard atmosphere shall have a temperature of 20,0 °C and a relative humidity of 65,0 %.
3.2.3 Tropical standard atmosphere
The alternative tropical standard atmosphere shall have a temperature of 27,0 °C and a relative humidity of 65,0 %.
3.3 Tolerance zone for standard atmospheres
The tolerance for temperature is土2,0。C. The tolerance for relative humidityis 土5,0 %.
4 Design of press knives
The design of press knives is shown in Figure 1. The internal surfaces shall be perpendicular to the plane which contains the cutting edge. The angle formed between the internal and external surfaces of the press knife at the cutting edge shall be approximately 20°, and the wedge of this angle shall be of a depth (d) exceeding the thickness of the leather.
NOTE
Hardened, knife-grade steel is suitable for press knives.
5 Preparation of test pieces
Prepare test pieces by applying the press knife to the grain surface (or simulated grain surface) if present. If no grain or simulated grain is present, apply the press knife to either surface. If preferred, leather may be conditioned (see Clause 6) before test pieces are prepared.
6 Conditioning
Condition the sample by keeping it in one of the standard atmospheres specified in Clause 3. Support the sample to allow free access of air to all surfaces, keeping the air in motion around it (see 2.3). Condition the test pieces for a minimum of 24 h prior to testing.
The 24 h conditioning is for dry leathers. Leathers with high moisture contents should be dried prior to conditioning.ISO 2419 pdf download.