Leather Testing Methods-Preparation of Samples for Analysis

The leather specimen for the chemical analysis is passed through a cutter mill, and the pulverized leather is called ”leather powder” or ground leather.

Suitable for this purpose are all types of mills fitted with a 4 mm screen and driven at a speed of 700 –1000 r.p.m.

Sampling according to IUC/2 and IUP/2:

1. Sampling location for skins, whole hides and sides

2. Sampling location for shoulders

3. Sampling location for bends

4. Sampling location for bellies (flanks)


a. sampling location, if no physical tests are required
b. sampling location, if physical tests are required

Regards,

Leather Testing Methods- Physical Leather Testing Method

The official methods of the International Leather Chemists’ Societies for chemical leather analysis are denoted by the letters IUC and that for the physical testing of leather by the letters IUP. Most of them have been adopted as official methods.The letters DIN denote the official leather test methods of the German Standard Committee. Most of them have been drawn up in conformance with the IUC and IUP methods. Here we will discuss Physical Leather Testing method.
Methods of Physical Leather Testing:
IUP /1	General remarks
IUP/2	Sampling
	= factually corresponding with DIN 53302/part 1
IUP/3	Conditioning in standard atmosphere(65 ± 2 % RH and 20 ± 2 °C; DIN 50 % RH, 23 ± 2 °C)
	= factually corresponding with DIN 50014-2
IUP/4	Measurement of thickness
	= factually corresponding with DIN 53326
IUP/5	Measurement of density
	= factually corresponding with DIN 53327
IUP/6	Measurement of tensile strength, elongation at break and maximumforce
	= factually corresponding with DIN 53328
IUP/7	Measurement of absorption of water (Kubelka)
	= factually corresponding with DIN 53330
IUP/8	Measurement of tearing load
	= factually corresponding with DIN 53329
IUP/9	Measurement of distension and strength of grain by the ball burst test (Lastometer)
	= factually corresponding with DIN 53325
IUP/10	Dynamic waterproofness test (Penetrometer)
	= factually corresponding with DIN 53338/part 1
IUP/11	Dynamic waterproofness test for boot and shoe sole leather
	= factually corresponding with DIN 53338/part 2
IUP/12	Measurement of resistance to grain cracking
	= factually corresponding with DIN 53324
IUP/13	Measurement of two-dimensional extension (Tensometer)
	= factually corresponding with DIN 53323
IUP/14	Measurement of the waterproofness of gloving leathers
	= no corresponding DIN test method available
IUP/15	Measurement of water vapour permeability
	= factually corresponding with DIN 53333
IUP/16	Measurement of shrinkage temperature
	= factually corresponding with DIN 53336
IUP/17	Measurement of resistance of air-dried insole leather to heat, particularly during direct vulcanization
	= no corresponding DIN test method available
IUP/18	Determination of the resistance of air-dried lining leather to heat, particularly during direct vulcanization
	= no corresponding DIN test method available
IUP/19	Determination of the resistance of dry upper leather to heat, particularly in direct vulcanization and in moulding on soles during shoe production
	= no corresponding DIN test method available
IUP/20	Determination of the flexing endurance of light leathers and their surface finishes (dry and wet) in flexometer
	= factually corresponding with DIN 53351
IUP/21	Measurement of set in lasting with the dome plasticity apparatus (Plastometer)
	= no corresponding DIN test method available
IUP/22	The assessment of surface damage by use of the viewing box
	= no corresponding DIN test method available
IUP/23	Measurement of damage caused by scuff
	= no corresponding DIN test method available
IUP/24	Measurement of surface shrinkage by immersion in hot water
IUP/26	Measurement of abrasion resistance of sole leather
IUP/28	Measurement of resistance to bending of heavy leather
IUP/29	Determination of cold crack resistance of finishes
	= factually corresponding with DIN EN ISO 13333
IUP/30	Determination of water vapour absorption and desorption in relation to dimensional changes in the leather
IUP/32	Measurement of surface area (provisional draft)
	= factually corresponding with ISO 11646
DIN standards not within the IUP range: DIN 53331 Determination of stitch tear strength. DIN 53332 Determination of water vapour absorption. DIN 53340 Determination of flexing endurance of low flexibility leathers. DIN 53344 Determination of resistance for hydrolysis of finished and unfinished leathers. DIN 75200 Determination of fire resistance. DIN 75201 Determination of fogging characteristics of trim materials in motor vehicles. Method A: determination with 60° reflectometer. Method B: gravimetric determination. DIN 75202 Determination of light fastness of trim materials in motor vehicles using the Xenon arc light. DIN EN 344-1 Protective shoes. DIN EN 374-1 Protective gloves.

DIN EN ISO 105B-02 Colour fastness to artificial light.

Regards,

Leather Testing Methods by Padana

PADANA GARMENTS is one of the few companies in the world with full wet-end development and production capabilities. From preserving hides, to following precise steps in the manufacturing process, we exercise the complete control that ensures our leather is the most acclaimed in the industry.
Leather Testing Methods:
Here are some of the details of Leather Testing Methods;

IUC/IUP-methodsThe official methods of the International Leather Chemists’ Societies for chemical leather analysis are denoted by the letters IUC and that for the physical testing of leather by the letters IUP. Most of them have been adopted as official methods. The letters DIN denote the official leather test methods of the German Standard Committee. Most of them have been drawn up in conformance with the IUC and IUP methods.

Methods of chemical leather analysis:

IUC/1	General remarks and presentation of analytical results
	= factually corresponding with DIN 53300/part 2
IUC/2	Sampling (as in IUP/2)
	= factually corresponding with DIN 53302/part 2
IUC/3	Preparing the test material by disintegration
	= factually corresponding with DIN EN ISO 4044
IUC/4	Determination of substances extractable with dichloromethane
	= factually corresponding with DIN EN ISO 4048
IUC/5	Determination of the water content of leather
	= factually corresponding with DIN 53304
IUC/6	Determination of organic and inorganic substances in leather removable by washing (loss by washing)
	= factually corresponding with DIN 53307
IUC/7	Determination of ash and water-insoluble mineral substances
	= factually corresponding with DIN EN ISO 4047
IUC/8	Determination of chromium content
	= factually corresponding with DIN 53309
IUC/9	Determination of water soluble magnesium salts in leather (epsom salt)
	= factually corresponding with DIN EN ISO 5399
IUC/10	Determination of nitrogen, ammonium and skin substance
	= factually corresponding with DIN 53308
IUC/11	Determination of pH and difference value of aqueous leather extract
	= factually corresponding with DIN EN ISO4045
IUC/13	Determination of zirconium
	= no corresponding DIN test method available
IUC/15	Determination of phosphorus
	= no corresponding DIN test method available
IUC/16	Determination of aluminium
	= no corresponding DIN test method available
IUC/17	Determination of hydroxyproline
	= no corresponding DIN test method available

DIN standards not within the IUC range

DIN 53314 Determination of chromium (VI) compounds in leather
DIN 53315 Determination of formaldehyde in leather

The following methods are in the course of preparation and have not yetbeen adopted as official methods:
a. Determination of iron in leather
b. Determination of free fatty acids in leather
c. Determination of extractable fat (chamois leather)
d. Determination of sulfur in leather
e. Determination of glutaraldehyde in leather
f. Determination of pentachlorophenol (PCP) in leather

Rgards,