CEN/TC 289/WG 2 - Physical test methods

This document specifies a method for the determination of free and released formaldehyde in leathers. This method, based on high performance liquid chromatography (HPLC), is selective and not sensitive to coloured extracts and is intended to be used for precise quantification of formaldehyde.
The formaldehyde content is taken to be the quantity of free-formaldehyde and formaldehyde extracted through hydrolysis contained in a water extract from the leather under standard conditions.

ISO 23910:2017 specifies a method for determining the stitch tear resistance of leather. It can be used on all leathers but is particularly suitable for leathers over 1,2 mm in thickness.

ISO 17232:2017 specifies two methods for determining the heat resistance of patent leather.
Method A makes use of a modified lastometer, while Method B uses the "Zwik" apparatus. Both methods are applicable to patent leathers for all end uses.

ISO 3377-2:2016 specifies a method for determining the tear strength of leather using a double edged tear. The method is sometimes described as the Baumann tear. It is applicable to all types of leather.

ISO 2417:2016 specifies a method for determining the water absorption of leather under static conditions. The method is applicable to all leather, particularly heavy leather.

ISO 3379:2015 specifies a test method for the determination of distension and strength of the leather grain or finished surface. This method is applicable to all flexible leathers and it is particularly suitable to determine the lastability of leathers for footwear uppers.

ISO 17130:2013 specifies a method of determining the dimensional change (shrinkage) of leathers caused by ageing. It is applicable to all leathers.

ISO 14268:2012 describes a method for determining the water vapour permeability of leather and provides alternative methods of sample preparation.

ISO 17076-1:2012 specifies a method of determining the abrasion resistance of leather using a Taber apparatus.

ISO 26082-1:2012 specifies a method for determining the resistance of all forms of leather to visible soiling through repeated contact with soiled objects. It provides a physical pretreatment routine for leathers that may be vulnerable to loss of soiling resistance while in service, prior to conducting further tests such as cleaning.

ISO 2419:2012 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.

ISO 5402-1:2011 specifies a method for determining the wet or dry flex resistance of leather and finishes applied to leather. It is applicable to all types of flexible leather which are less than 3,0 mm thick.

ISO 3376:2011 specifies a method for determining the tensile strength, elongation at a specified load and elongation at break of leather. It is applicable to all types of leather.

ISO 5403-1:2011 specifies a method for determining the dynamic water resistance of leather by means of repeated linear compression. It is applicable to all flexible leathers but is particularly suitable for leathers intended for footwear applications.

ISO 14087:2011 describes a test method for the determination of the bending force of leather.

ISO 17231:2006 specifies a method for determining the repellency of leather to surface wetting. It is applicable to all leathers intended for use in clothing. The method does not determine the resistance of leather to water penetration.

ISO - Taking over of an ISO Technical Corrigendum

ISO 17226-1:2008 specifies a method for the determination of free and released formaldehyde in leathers. This method is based on high performance liquid chromatography (HPLC). It is selective and not sensitive to coloured extracts.
The formaldehyde content is taken to be the quantity of free-formaldehyde and formaldehyde extracted through hydrolysis contained in a water extract from the leather under standard conditions.

ISO 17226-2:2008 specifies a method for the determination of free and released formaldehyde in leathers. This method is based on colorimetric analysis.
The formaldehyde content is taken to be the quantity of free-formaldehyde and formaldehyde extracted through hydrolysis contained in a water extract from the leather under standard conditions
This process is not absolutely selective for formaldehyde. Other compounds such as extracted dyes could interfere at 412 nm.

ISO 17075:2007 specifies a method for determining chromium(VI) in solutions leached from leather under defined conditions. The method described is suitable to quantify the chromium(VI) content in leathers down to 3 mg/kg.

ISO 23910:2007 specifies a method for determining the stitch tear resistance of leather. It can be used on all leathers, but is particularly suitable for leathers over 1,2 mm in thickness.

ISO 5398-4:2007 describes a method for the determination of chromium in aqueous solution obtained from leather. This is an analysis for total chromium in leather; it is not compound specific or specific to its oxidation state.
This method describes the determination of chromium by inductively coupled plasma – optical emission spectrometry and is applicable to leathers which are expected to have chromic oxide contents in excess of 1 mg/kg. Two techniques for the preparation of the solution to be analysed are included. In the case of dispute, the wet oxidation technique is to be used.

ISO 5398-1:2007 describes a method for the determination of chromium in aqueous solution obtained from leather. This is an analysis for total chromium in leather; it is not compound specific or specific to its oxidation state.
This method describes the determination of chrome by iodometric titration and is to be applicable to chromium-tanned leathers which are expected to have chromic oxide contents in excess of 0,3 %. Two different methods are described as alternatives for obtaining chromium in a suitable solution. It is appropriate to use either method.

ISO 17070:2006 specifies a method for determining the content of pentachlorophenol (PCP), its salts and esters in leather.

Over time, the surface colour of leather and the leather itself change due to ageing and to the action of the surroundings on the leather. The purpose of the various ageing procedures described in ISO 17228:2005 is to obtain an indication of the changes that could occur when leather is exposed to a certain environment for a prolonged time. The test conditions to be used depend on the type of leather and its intended use.

ISO 4098:2006 specifies a method of determination of water-soluble matter, water-soluble inorganic matter and water-soluble organic matter. It is applicable to all leather types.

ISO 2417:2002 specifies a method for determining the water absorption of leather under static conditions. The method is applicable to all leather, particularly heavy leather.

ISO 3377-2:2002 specifies a method for determining the tear strength of leather using a double-edged tear. The method is sometimes described as the Baumann tear. It is applicable to all types of leather.

ISO 17229:2002 specifies a method for determining the water vapour absorption of leather. The method is applicable for all leathers but is particularly relevant for leathers intended for footwear uppers and linings.

ISO 2420:2002 specifies a method for determining the apparent density of leather. It is applicable to all heavy leather.

ISO 17233:2002 specifies a method for determining the cold crack temperature of surface coatings applied to leather. It is applicable to all leathers which have a surface coating and which can be easily flexed.

ISO 2418:2002 specifies the location of a laboratory sample within a piece of leather and the method of labelling and marking the laboratory samples for future identification.
It is applicable to all types of leather derived from mammals irrespective of the tanning used.
It is not applicable to leathers derived from birds, fish or reptiles.

ISO 2589:2002 specifies a method for determining the thickness of leather. The method is applicable to all types of leather of any tannage. The measurement is valid for both the whole leather and a test sample.

ISO 3380:2002 specifies a method for determination of the shrinkage temperature of leather up to 100 °C. It is applicable to all leathers.

ISO 2418:2017 specifies the location of a laboratory sample within a piece of leather and the method of labelling and marking the laboratory samples for future identification.
It is applicable to all types of leather derived from mammals irrespective of the tanning used.
It is not applicable to leathers derived from birds, fish, reptiles or furs.

ISO 5402-1:2017 specifies a method for determining the wet or dry flex resistance of leather and finishes applied to leather. It is applicable to all types of flexible leather below 3,0 mm in thickness.

ISO 17236:2016 specifies a method for determining the extension set of leather. It is intended for use on upholstery leather but is applicable to all flexible leathers.

ISO 17235:2011 specifies a non-destructive method for determining the softness of a leather. It is applicable to all non-rigid leathers, e.g. shoe-upper leather, upholstery leather, leather-goods leather and apparel leather

ISO 17236:2002 specifies a method for determining the extension set of leather. It is intended for use on upholstery leather but is applicable to all flexible leathers.

Migrated from Progress Sheet (TC Comment) (2000-07-10): Meeting on 971204/05: Waiting ISO/FDIS 15701 approval  980218 (TA/971219) ++ TC Res.14/1996: V.A.to be clarified (TA)

The principle of the method specified is measuring the area of the conditioned leather with a mechanical pin-wheel machine. Is intended only for the measurement of dressed and other dry flexible leather.

The principle of the method specified is soaking a leather specimen and also a piece of adjacent fabric, laid against each side to be tested, in artificial perspiration solution, leaving the composite specimen under pressure for a specified time in a suitable apparatus, drying the leather specimen and adjacent fabric, and assessing the change in colour of the specimen and the staining of the adjacent fabric with the grey scales. Leathers with a finish may be tested intact or with the finish broken. The method is applicable to leather of all kinds at all stages of processing.

The principle of the method specified is rubbing one side of the leather to be tested with pieces of reference wool felt under a given pressure for a given number of forward and backward motions, assessing the change in colour of the pieces of felt and of the leather with the grey scales. Any other visible change in or damage to the surface of the leather is also reported.

ISO 14268:2002 describes a method for determining the water vapour permeability of leather and provides alternative methods of sample preparation. It is applicable to all leathers below 3,0 mm thickness.

ISO 26082:2007 specifies, for pigmented leathers, a method for the determination of the change in colour of the leather after rubbing with a standard soiling cloth. While this method could be used for all leathers, it is particularly applicable to upholstery leathers with a finish coat, especially leather intended for automotive use.

ISO 2419:2006 specifies the preparation of leather test pieces for physical and mechanical testing together with two standard atmospheres for conditioning and testing. It is applicable to all types of dry leather.

ISO 5404:2002 specifies a method for determining the water resistance of heavy leathers. The method allows determination of the penetration time, water absorption, area of penetration and water penetration rate as required. It is applicable to all types of heavy leathers.

ISO 5403:2002 specifies a method for determining the dynamic water resistance of leather. It is applicable to all flexible leathers but is particularly suitable for leathers intended for footwear uppers.

ISO 5402:2002 specifies a method for determining the wet or dry flex resistance of leather and finishes applied to leather. It is applicable to all types of leather below 3,0 mm in thickness.

ISO 3376:2002 specifies a method for determining the tensile strength, elongation at a specified load and elongation at break of leather. It is applicable to all types of leather.