Problems,
Reasons And Solutions In Leather Finishing |
| Problems |
|
Reasons |
|
Solutions |
1.Coarse
Grain Break |
|
It
may be caused by the use of unsuitable
binders, those does not adhere tightly
and does not penetrate deeply into the
leather. |
|
The
coats should be kept thin, binders and
pigments should have good dispersion
and penetration properties such as Akral
RF 403, Akral RF 901 and Lustratop Pigments.
|
|
| 2.Weak Films |
|
Due to poor finish formulation |
|
Film
must have a certain amount of strength
to withstand flexing and stretching
of the leather with Akral RF 901, Akral
RF 403 and Resofinish 1020.
|
|
3.Bronzing |
|
Finishing
dyes or pigments loading can cause bronzing
as red and wine burgundy shades. |
|
Use
recommended quantity of dye and pigments
as article required and use inorganic
pigments to avoid bronzing like Lacsuper
dyes and Lustratop Pigments.
|
|
| 4.Poor Coverage |
|
May
be caused by the settling out of pigments
in the finish mixture. It can also be
caused as grain enamel damages, grain
slip and abraded grains.
|
|
Should
use good quality inorganic dispersing
pigments and use quantity of pigments
and binders as per leather requirement. |
|
5.Crocking
(Rubfastness) |
|
a) It can be caused by
using excess
quantity of liquid
dyes.
b) It can be caused by using organic
pigments.
c) It can be caused by improper
fixation
of finish.
|
|
Use
recommended proportion of dye and inorganic
pigments with cross linker or polyurethene
binder such as Alparet AZ, RPU 022,
RPU 048 and RPU 205 C.
|
|
| 6.Poor Adhesion |
|
Using improper sealing or polishing
ground or sometimes using cationic
auxiliaries at the end of dyeing process
|
|
First check leather absorption and then
select sealing or polishing ground such
as Prefondal K 72, Prefondal K-53 and
SFT F 6013 A. Also use good penetrator
and crosslinker like RPU K-050 to improve
adhesion. |
|
