Choose language
  • Nederlands
  • Duits
  • Engels
  • Frans
  • Chinees
Aako BV
P.O. Box 205
3830 AE Leusden
The Netherlands
KvK 31009627

Coriagen V New

CAS number:
Product type
Leather agents


Polyphosphate long chain-length

Appearance white fine agglomerate, hygroscopic


By using CORIAGEN V new after liming, the harmful effects on the pelts of water hardness, as well as of lime and iron compounds, can be prevented or at least considerably reduced.
Even small amounts of CORIAGEN V new give entirely smooth and pure white pelts yielding a pale and uniformly coloured leather. For this reason, the addition of CORIAGEN V new is particularly recommended for those types of leather which are to be slightly pigmented or semianillin- finished.

A few grams of CORIAGEN V new per m of water will prevent the formation of a crystalline calcium carbonate precipitate on the grain, which is responsible for the rough handle of the limed pelts after the rinsing and washing processes. This effect is known as „sulfate seeding“.

The emulsifying and dispersing properties of CORIAGEN V new faciliates the removal of the natural fat and scudding. Furthermore, CORIAGEN V new supports the newtralisation of Calciumhydroxide during the deliming process.

When used in the processing of pickled pelts into vegetable or synthetic tanned leather, CORIAGEN V new not only facilitates the procedure considerably but also improves the leather quality distinctly. The use of CORIAGEN V new enables the pelts to be depickled and pretanned in one pass, without the addition of salt. The salts can then be removed by rinsing without the risk of swelling. At the same time, part of the natural fat of the skins and hides is also removed.

Depickling with CORIAGEN V new can safely be combined with degreasing in the wet.

Leather treated with CORIAGEN V new presents a light and uniform colour with excellent tear strength, a particular advantage for sheep leather and skivers. The resistance to light and other atmospheric influences is distinctly improved. The leather can be dyed and plated without difficulty. The shades of dyed leather are brighter.
In the manufacture of sole leather, CORIAGEN V new not only reduces the tanning time considerably, but also provides a light and evenly coloured leather with improved elasticity and resistance to wear. More tight and compact leather properties are obtained.
The use of CORIAGEN V new in the pretannage process protects the hides and skins from a premature attack of the tanning agents, this enables the use of fairly concentrated tanning liquors right from the start. Furthermore, CORIAGEN V new complexes all calcium and iron compounds on the pelts, thus preventing lime specks and iron discoloration.

Leather pretanned with CORIAGEN V new generally has a somewhat higher tanning number; its pH and difference value are excellent. The mineral substance content of the leather is not increased by CORIAGEN V new.

Pretanning with CORIAGEN V new, prevents vegetable or synthetic tanning agents of being bound too fast on the surface of hides and skins, thus avoiding grain drawing or case hardening, even when tanning immediately in strong liquors. Vegetable tanning can, therefore, be carried out directly in the drum. The tanning substances penetrate hides and skins pretanned with CORIAGEN V new rapidly and easily, thus reducing the tanning time. The tanning liquors are more rapidly and completely exhausted and the loss in tanning substances is reduced to a minimum.

Leather pretanned with CORIAGEN V new possesses a surprisingly light and even colour. It has a full and firm handle and excellent mechanical properties, in particular high tensile strength, good grain elasticity and increased resistance to wear.

The natural grease contained in the hides and skins is largely removed by pretanning with CORIAGEN V new. The residual grease is distributed evenly, so that fat stains in the finished leather, particularly noticable on sheep and pig skins, are reliably avoided.
The effect of CORIAGEN V new is based principally upon the displacement of the hydrolyzable acids residue by the polyphosphoric acids with complexing capacity, rather than on the newtralization of the free acid. As a result of this, a mild and uniform newtralizing effect is obtained. Because of its high affinity for chromium, CORIAGEN V new is almost entirely linked by the leather, especially in the papillar layer.

CORIAGEN V new has an anionic character and reduces the positive charge of chrome-tanned leather. The spontaneous appearance of vegetable or synthetic tanning agents on the surface is retarded and coarsening or cracking of the grain prevented. Penetration of the tanning agents into the leather core is facilitated. For the same reason, CORIAGEN V new acts as a levelling agent when used in dyeing processes with acid and substantive dyes. The product promotes the penetration of the fat substances in to the leather core, so that the portion of newtral oil can be increased and the total amount of fat reduced.

newtralizing of the leather with CORIAGEN V new enhances the absorption of cationic substances considerably, such as basic chromium and aluminium salts. This, in turn, improves the fullness of the leather and reduces the chromium content in the tannery effluent.

Search in Industrial chemicals
Aako BV
P.O. Box 205
3830 AE Leusden
The Netherlands
More contact information »