ISO 2419-2012 pdf free.Leather — Physical and mechanicaltests — Sample preparation andconditioning.
1 Scope This International Standard specifies the preparation of leather for physical and mechanical testing togetherwith standard atmospheres for conditioning and testing. lt is applicable to all types of dry leather.
2Terms 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 timebefore being subjected to testing.
2.3 conditioning operation designed to bring a sample into a specified condition in relation to temperature and relative humidityby keeping it for a given period of time in the standard atmosphere with free access of moving air to allsurfaces.
3 Standard atmospheres
3.1Reference standard atmosphere The reference standard atmosphere shall have a temperature of 23,0 °C and a relative humidity of 50,0 %.3.2Alternative standard atmospheres
3.2.1 General Alternative, but not equivalent, atmospheres may be used only if the parties involved agree on their use. Incase of dispute, the reference standard atmosphere shall be used.
3.2.2Specific standard atmosphere The alternative specific standard atmosphere shall have a temperature of 20,0 ℃C and a relative humidity of65,0 %.
3.2.3Tropical standard atmosphere
The alternative tropical standard atmosphere shall have a temperature of 27,0 °C and a relative humidity of65,0 %.
3.3Tolerance zone for standard atmospheres
The tolerance for temperature is ±2,0 °C.The tolerance for relative humidity is ±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 planewhich contains the cutting edge. The angle formed between the internal and external surfaces of the pressknife at the cutting edge shall be approximately 20° , and the wedge of this angle shall be of a depth (a)exceeding the thickness of the leather.
5 Preparation of test pieces
Prepare test pieces by applying the press knife to the grain surface (or simulated grain surface) if present. Ifno grain or simulated grain is present, apply the press knife to either surface. lf preferred, leather may beconditioned (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 thesample to allow free access of air to all surfaces,keeping the air in motion around it (see 2.3).Condition thetest 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 toconditioning.ISO 2419 pdf download.