Leather batch
In the tannery, the leather goes through the tanning and dyeing process in batches. Since only a certain amount of leather skins fits into a tanning drum, the appropriate quantities are combined into a batch and go through all the processes together. A lot usually contains 50 - 100 skins. It can therefore be assumed that the leather of one batch are very similar.
In case of leathers, where an exact equality is not possible, there are differences from batch to batch. This is also referred to as "batch deviations". Pull up leather or aniline leather is not easy to be produced always with same appearance. Depending on the lot, they may differ in the end. Leather traders who have such leathers in their program must explain these deviations clearly to the customer so that this does do not lead to misunderstandings. The best is to show two maximally different leather samples. The customer then sees which variance the batch deviations have.
Examination of the colour accuracy of leather with the grey scale.
Often, the buyer presumes that the quality is not sufficient, if deviations occur on a second delivery. For leather specialists, this is understandable. Only experts know how strong differences can be in some leather types. Within a batch and from batch to batch. In the case of disputes, only qualified auditors can then decide whether the deviation is permissible or not. Various measurement methods are available for measuring colour and brightness differences.
Only a certain number of hides can always be processed together.
The car manufacturers have the highest demand for the equality of colours, grain structures and quality. But even here, slight colour differences can occur.
Even car leather of BMW in "black" of same type of leather is not always 100% identical.
The more porous and natural leather is, the more the differences can be.
In the cases of the following photos, the customers had purchased vintage leather as semi-nubuck or pull-up leather and had either only seen one version as a pattern and had noticed the deviation when the furniture was purchased or when they received furniture parts, which were delivered later.
In such cases, a better advising with photos or patterns could have helped causing misunderstandings. Often, this important communication, which would be possible, does not take place. Even the tannery should ideally point the leather dealer to the possible variance of the batches. Also, the experienced leather trader would have to point out his customers differences in batches. Ideally with patterns that represent well the maximum variance.
If a customer wants to buy additional furniture, the furniture dealer should send photos and samples to the manufacturer, so that one remains as close to the customers leather as possible. If this is not enough, the manufacturer has to send samples to the customer, which he can put on the existing furniture to compare. This is complex and expensive, but still better than a complaint, which is annoying for everyone and also expensive.
Strong deviation of leather on later bought furniture. Even for professionals a strong batch deviation.
Difference of leather pattern in the furniture house to delivered furniture. For leather specialists still in the allowed range.
Additional bought oiled nubuck with mentioning the variation of the look in the online shop. Therefore, still within the scope of permissible batch variances in leather.
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