NUBUCK
1-
OBJECTIVE
Nubuck is top-grain cattle rawhide leather that has been sanded or
buffed on the grain side, or outside, to give a slight nap of short protein
fibers, producing a velvet-like surface. It is resistant to wear, and may be
white or coloured.Nubuck is similar to suede. It differs in that suede is
created from the inner side of a hide, whereas nubuck is created from the outer
side of a hide, giving it more strength and thickness along with a fine
grain.It is generally more expensive than suede, and must be coloured or dyed
heavily to cover up the sanding and stamping process.
2-
OBSERVATION
ABOUT LEATHER
We observed about the cowhide
which coming from salted conservation before starting to the process. The
salted cowhides was extremely fragile and high hardness. Folding the cowhide
was very difficult. The hair had broken off easily. We saw some defect on the
surface of cowhide because the bacterial effect given damage to the rawhides.
Some area of the raw was cut and the corners was needed pruning
3-
MAIN FORMULA
AND MODIFY FORMULA
4-
TECHNICAL
INFORMATION AND CHEMICALS USED
We used
backbone region of leather.In soaking process we used more water than
normally because of raw hides had lots of pollution and we didnt use paddle. we
wash twice time because float is very
dirty and a lot of hair.That’s why we discharged drum again and again.We used
to tensioactivo.It is soaking agent for salted hides and skins) for helping the
soaking and speed up to process and bactericide for prevent to raw from bacterial
attack.In addition we used sodium carbonate,sodium sulphydrate and sodium
hydroxide for increase pH controlled.While increasing pH this chemicals help to
decay of hair and hair follicle.After leather waited one night ın outomatic
next day we started unhairing process.In unhairing we used calcium hydroxide
and sodium sulphur. Calcium Hydroxide occur with burning to calcium oxide; then
there is exothermic reaction and the calcium oxide turning to Calcium Hydroxide.And
we used amine amine compounds are employed with the aim to enchance the effect
of hair attack and minimise the amount of sulphur.In liming process we used
anionic tensioactive because we used alkaline float.In addition we used sodium
bisülfite,amonium sulphate for increase the pH after we added dicarboxylic acid
for balance pH to enzyme activity.Finally we added pancreatic enzyme for
deliming.The aim of this products hydrolized to epidermal structure for
eliminate the hair, provided to controlled swelling of hide and reveal to
reactive amino and carboxyl groups of collagen.We used to deliming agents for
decrease the pH to 8,0-8,5 because the pancreatic bating enzyme is working with
8,2 ph value. After this process we checked the cross section pH value with
using phenolphthalein.we put leather into a new float with water and formic
acid we got the Ph 3.5.than we applied
tanning we used autobasifyng chrome salt we finished tanning at pH:3.7 and we applied sammying for get
away water from leather.we washed leather and retanning with chrome salt %33
basic and with neutralisation we got the pH to the 5. in dyeing and greasing we
used acrilic resyn (RETANAL RCN 40)it Improves the fullness and softness of
retanned leathers without affecting the typical chrometanned character of the
leather.we gave 2% of dye in one time and we used synthetic dispersant (TAMOL
M) to obtain homogenius dyeing. and we used Synthetic fatliquoring agent
(PELLOSTOL XO) it gives very tight grain
roundnessespecially equal dyeings excellent stability to heat yellowing and light fastness fine grain .and
we used MAGNOPAL® SOF – Polymer based softening agent it has excellent
softening properties and is applied alone or in combination with conventional
anionic fatliquors. The product is fixed in a nearly unextractable form to the
leather fibre and is therefore ideally suited for washable and drycleanable garment
nappa from hides and skins.aqnd we used TRUPON ® SWS fatliquor for suede and
nubuck leather. TRUPON SWS is a fully synthetic fatliquor designed to produce
outstanding gloss and sheen on both suede and nubuck leathers. TRUPON SWS
possesses excellent light fastness and resistance to yellowing caused by heat or ageing. TRUPON
SWS will not bleach or lighten anionic dyeings. Leathers fatliquored with
TRUPON SWS exhibit good softness and a pleasant, slightly waxy handle.
5-
FINAL OBSERVATION AND CONCLUSIONS
After the final all
of the process we outed the crispy from drum and reviewed their touch.buff the
grain and we obtain this special writing effect.dyeing was not so good because
in flesh side when buffing we saw not good penetration.in the nubuck we can see
conservation mistakes beter,it becomes more visible.problem of nubuck is colour
fastness when we rub the nubuck on a paper we can see its leaving colour thats
because of powder fix electrostatic to the fiber if we do first buffing than
dyeing we obtain beter results.in nubuck process first we make crust and buff
and in drum dyeing when dried we mill so we could have some effect without
powder.characteristic depends on where its gona be used so we dont discuss
about it.
Tamol M
Nature Condensation product
of aromatic sulfonic acids.
pH value (10 % solution in
demineralized water): ca. 7
Solids content: ca. 95 %
Storage The product may be
stored for one year in closed original containers at
temperatures below 40 °C.
Properties
Tamol M is a fine, beige
powder which dissolves readily in water forming
solutions of almost
neutral reaction. The product substantially accelerates
the penetration of
vegetable tannins by reducing their tendency to form
large and highly
astringent particles.
Tamol M improves the
tanning effect of, say, mimosa and quebracho
extracts, by bringing
about a more rapid and more uniform dispersion.
If mimosa extract is used
alone, however, it is advisable to incorporate a
synthetic replacement
tanning agent besides Tamol M.
Application
Tamol M is mainly used for
retanning chrome leathers with vegetable extracts
to promote the
neutralization process and to achieve a more uniform
and milder absorption as
well as a deeper penetration of the retanning
agents.
Thus, the grain layer is
no longer overloaded and retains its full elasticity
even if fairly astringent
tanning agents, e.g., mimosa or lightly sulfited quebracho
extracts are used.
Tamol M can also be used
to advantage for neutralization. When applied in
conjunction with Neutrigan
®
, Neutrigan P 4 and other
commonly employed
neutralizing agents, the
product mainly facilitates complete penetration
that is often difficult to
achieve in dyeing fairly thick leathers.
TRUPON ® SWS
fatliquor for suede and nubuck leather
Basis:
fully synthetic sulphated raw materials
Appearance:
red brown oil
Charge:
anionic
Active matter:
approx. 78 %
pH value (1 : 10): approx. 7.5
Acid stability: medium
Salt stability: low
Chrome stability: not recommended in chrome baths
Light fastness: excellent
Heat yellowing: excellent
Properties:
TRUPON SWS is a fully synthetic fatliquor
designed to produce outstanding gloss and sheen on both suede and nubuck
leathers.
TRUPON SWS possesses excellent light fastness
and resistance to yellowing caused by
heat or ageing. TRUPON SWS will not bleach or
lighten anionic dyeings.
Leathers fatliquored with TRUPON SWS exhibit
good softness and a pleasant, slightly waxy handle.
Application:
For suede splits 4 - 6 %, based upon shaved
weight.
For goat suede 4 - 10 %, based upon shaved
weight.
When used on sheep nappa and nubuck at levels
of 4 - 6 %, based on shaved weight,
TRUPON SWS will help produce leathers with a
full round handle whilst simultaneously
improving the brilliance of anionic dyeings.
04/2003
The information given in this technical
leaflet is offered in good faith and is based upon our knowledge and experience
of the
products used. The suitability of the products
mentioned to obtain specific properties or effects are given without obligation
or guarantee and should be fully tested by the
end user and adapted to suit prevailing works conditions or other products
which may be employed.
TRUPON: registered trademark of TRUMPLER
TRUPON SWS - 2 - Safety and storage:
When handling
TRUPON SWS, normal safety precautions associated with the handling of
chemicals should be observed. For more
specific details please refer to our safety data sheets.
TRUPON SWS can be stored for up to one year,
if temperatures below 5 °C and above 40 °C
can be avoided. On prolonged storage or
extremes of temperature TRUPON SWS may
exhibit some settlement which can be rectified
by either warming and/or stirring the product
thoroughly before use.
MAGNOPAL®
SOF – Polymer based softening agent
Our application recommendations are in line
with our present state of knowledge. They do not, however, exempt the customer
from
performing his own tests to determine the
suitability of the supplied products for their intended purposes. Application
of the products lies
Features MAGNOPAL®SOF is a white to slightly
beige paste based on an acrylic polymer.
Charge: Anionic.
Lightfastness: Very good.
Heat resistance: Very good.
Storage stability:
1 year (at room temperature).
Frost resistance:
Not sensitive to frost. In case of freezing
warm the product to approx.
20°C and homogenize by stirring.
Stability in mineral tanning floats:
Not stable.
Method of diluting:
Stir water at 60 °C at a ratio of 1 : 4 into
the product.
Benefits
MAGNOPAL®SOF has excellent softening properties and is applied
alone or in combination with conventional
anionic fatliquors.
The product is fixed in a nearly unextractable
form to the leather fibre and
is therefore ideally suited for washable and
drycleanable garment nappa
from hides and skins.
A combination of MAGNOPAL®
SOF and e.g. EUPILON®WAS-1 is
recommended for water resistant and washable
shoe upper leathers.
MAGNOPAL® SOF is highly stable against light
and heat-yellowing and is
therefore suitable for white upper leathers
for vulcanised or injection
moulded shoes.
Application
Washable Shoe Upper leather:
4.0 - 5.0 % MAGNOPAL®SOF
4.0 - 5.0 % EUPILON® WAS-1
(% based on shaved weight)
Water Resistant Shoe and
4.0 - 5.0 % MAGNOPAL® SOF
Boot leather:
4.0 - 5.0 % EUPILON® WAS-1
(% based on shaved weight)
Washable Garment Nappa:
5.0 % MAGNOPAL®SOF
3.0 % EUPILON® WAS-1
2.0 % PROPILON®BNV/W
(% based on shaved weight)
MAGNOPAL®SOF – Product characteristics
Trade form at 20°C paste
Appearance at 20°C White to slightly beige paste
pH - Value (20%) 7.0 - 8.0
Water Content (%) 44.0 - 47.0
This information is for guidance only.
A Product Specification is available on
request
RETANAL RCN 40
Polymers and Resins
|
RETANAL ARS
|
Liquid. Polymer retanning agent
producing a great fullness and giving from a gloving feel to a footwear box
feel, depending on the application conditions
|
|
RETANAL CAU aniónico
|
Liquid. Homopolymeric resin for
retanning. Anionic character
|
|
RETANAL CLE
|
Liquid. Resin pretanning and tanning
agent for chrome tannage
|
|
RETANAL CLE-10
|
Liquid. Acrylic resin for the pretannage
of chrome-tanned leathers, for wet white tannage and for retannage
|
|
RETANAL D-57
|
Powder. Melamine-dicyandiamide resin for
pretanning and retanning with selective filling agent
|
|
RETANAL DC
|
Powder. Resin anionic tannin. Melamine
condensate
|
|
RETANAL DU EXTRA
|
Powder. Retanning agent based on a
dicyandiamide resin which confers to the leathers a full feel. Suitable for
all kind of skins
|
|
RETANAL MD-80
|
Powder. Resin anionic tannin. Melamine
condensate
|
|
RETANAL MV EXTRA
|
Powder. Retanning agent based on
melamine, capable of adding softness and fullness to the skins. Suitable for
all kind of leathers
|
|
RETANAL RCN-30
|
Liquid. Acrylic polymer giving a good
filling effect, toegether with a soft feel and a springy handle
|
|
RETANAL RCN-40
|
Liquid. Anionic acrylic polymer in solution form
|
|
RETANAL RCN-70
|
Liquid. Resin copolymer with a good feel
and filling effect
|
|
RETANAL RC-200
|
Liquid. Acrylic resin giving a filling effect
to the leather, compactness to the grain and an excellent buffing ability
|
|
RETANAL RST y RST CONC
|
Liquid. Styrene-maleic resin with
softening effect
|
|
RETANAL UF-7
|
Liquid. Filling resin of soft feel
|
Productos
recurtientes
RETAHAL BH-10 ..........................
Sintan fenólico
RETANAL CLE
............................. Polímero acrílico (medio peso molecular)
RETANANAL D-57
...................... Resina melamina-diciandiamida
RETANAL RC-200
........................ Resina (metracrilato)
RETANAL RCN-40
....................... Resina acrílo-nitrilo
RETANAL RST
.............................. Resina estireno-maleica
RETANAL X-1
............................... Oxazolidina
ORGANIC FORMULAS
CH2 = CH-COOH
.................................. Acido acrílico
CH3 -CH = COOH
.................................. Acido metacrílico
CH3
CH2 = CH-CN .......................................
Acrilo nitrilo (RCN 40)
6-
BIBLIOGRAPHY
·
www.trumpler.de/.../TRUPON_SWS-e.pdf
·
CROMOGENIA-UNITS, S.A. (Factores que influyen en la hidrofugación con
polímeros recurtientes engrasantes (REPELAN PSH-171) Parte IIIFACTORES QUE
INFLUYEN EN LA HIDROFUGACION CON POLIMEROS RECURTIENTES ENGRASANTES (REPELAN
PSH-171) Laboratorio Curtidos Cromogenia-Units, S.A. Barcelona (España))
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