Posted: 26 January 2010 at 9:33am | IP Logged

Dear BenD:  I disagree!  If you want a cationic surface charge for dyeing purposes of , let's say, vegetable tanned leather, this mixture might be very useful!  Of course you could make it yourself by offering soluble aluminum salt and a neutral naftalene sulphonic syntan after a few minutes to get the same effect.  The Tannesco H/HN products may be initially have the sulphonic group complexed to chrome, but they separate soon as soon as chrome fixes to collagen carboxyls, regardless.  Sharphouse has a brief explanation of this phenomenon.  The reason why these products are interesting is that in effect you decouple simultaneously  saline links in collagen as the sulphonic containing syntans block charged aminos, then freeing anionic carboxyls that were previously saline linked to cationic aminos, making the carboxyls very astringent to cationic chrome.  That is why Tannesco HN helps exhaust chrome very well!

BASF used to offer the product in India as BILUTAN AL but I doubt they do anymore as a whole range of aluminum tannin products, that the CLRI developed, is being offered commercially in India by a local producer, and European Chemical firms are somewhat hesitant to recommend the use of aluminum because of its effect on many dyestuffs of making them much more brighter but in different hues, as Mexberger has pointed out with Black 210.  All of the very carefully planned color prediction schemes fall appart if aluminum is present!  The other problem is that there really is no annalogy in "basic aluminum sulphate" concept applicable to the use of aluminum products, such as exists in chrome applications.  Röhm & Haas failed with their chromesaver line of chemicals because tanners did not understant the pH differences for application of aluminum at basification.  Heidemann explains it, as aluminum being still very "labile" at pH 4,5 and needing a value of 5,8 to really fix well!  Some Fur tanners understand this better than most other tanners!

Posted: 26 January 2010 at 1:21pm | IP Logged

This is the original question by LeO-1:

I produced a piece of leather tanned with Basyntan AS - Aluminium Syntan, and the Ts is 75 C, the boiled cut show that the Syntan was not throughout the cut.

do Anybody have comments on the penetration of Aluminium Syntan?

how can we push them deeply inside?

As first tannin I believe it won't work. What I would like to ask  LeO-1 is: what kind of leather he wats to obtain and  get othter options.

But BenD is right, sometimes things can be done cheaper and easier.

Regards

Zercas

Posted: 26 January 2010 at 6:49pm | IP Logged

Penetration of aluminium tanning was depen on basicity. But It has some tendency to make bigger molecular as soon as it faced water. This phenomena was slower when it applied with citric acid. I found potash alum or just simple aluminium sulphate could do job rather than aluminium tanning agent.

Although there was no bondage between Al and syntan, I believe that will change very fast as soon as we introduced into water.

So far ihave not found any way of checking penetration of aluminum when it applied to wetblue 

Posted: 27 January 2010 at 7:13pm | IP Logged

Please tell me, I am using a spray deodorant that has Aluminum Chlorohydrate by a well known cosmetic brand.

Am I in trouble ?

Regards

Zercas