Present Status and Development Trend of Leather Chemicals
                              By Ji Feng
Leather chemicals are usually    classified  into  five  categories  of
tanning agents, greasing agents, finishing agents, special auxiliaries
and special dyes.
The leather industry is  the  basis  for  the  development  of  leather
chemicals. China occupies one-fifth of the world leather market,   and
still has great potentials for  further  expansion.   The  per- capita
leather consumption in China is far less than the world average.   The
export volume of leather products increased  from  350  million  U. S.
dollars in 1985 to 8.5 billion U.S. dollars in 1995,   accounting  for
one-fifth of the total export volume in the  light  industry.   As  is
projected from the development trend, the leather  industry  in  China
will grow at an average annual rate of around 5% by  the  end  of  the
century, and the output of leather (converted to oxhide) will reach 86
million pieces in 2000.
1. Present status
China started the production of leather  chemicals  in  the  mid- 60's.
There are more than 160 producers  today,   and  around  120  of  them
maintain stable production. Around 40 producers,  55%  being  chemical
enterprises and 45% being specialized  leather  enterprises,   have  a
capacity of over 500 t/a and their output  accounts  for  80%  of  the
national total.
Leather chemicals produced in China include tanning  agents,   greasing
agents,  finishing  agents  and  auxiliaries,   around  250  varieties
altogether. There is still a shortage of special dyes.  Most  domestic
products have a considerable gap in quality as compared  with  foreign
products. The domestic output is nearly 60 000 tons.
Major producers include Shanghai Leather Chemical Plant, Shanghai Xinhua
Leather Chemical Plant, Guangdong Zhongshan Tianfeng  Chemical  Plant,
Sichuan Shifang Tingjiang Chemical Plant, Chengdu  Wangjiang  Chemical
Plant of Sichuan General Chemical Works, Leather Chemical Co. (Tianjin
Leather Chemical Plant) of Tianjin Jingang (Group) Co., Ltd., Zhejiang
Leather Chemical Plant, Nanjing Leather Chemical Plant, Luzhou Leather
Chemical Plant, Beijing Leather Chemical  Plant  and  Dandong  Leather
Chemical Plant. These plants all have a capacity of over 2 000 t/a.
2. Development trend
(1) tanning agents
Tanning agents produced in China have more than  30  varieties  and  an
output of around 3 000 tons.
The development priority is on varieties with  features  of  bleaching,
light  stability,   perspiration  fastness,   leveling,   packing  and
neutralization. The production of titanium tanning  agents  which  can
replace chrome or reduce chrome consumption and chrome tanning  agents
with high absorption property will  be  promoted.   Acrylic  retanning
agents, melamine retanning agents and melamine  chrome  and  zirconium
complex retanning agents  with  excellent  packing  property  will  be
developed.
  The market demand will have a big margin increase  during  the  Ninth
Five-year Plan period, and the demand of retanning agents will  be  20
000 tons in 2000.
(2) greasing agents
Greasing agents produced in China have more than 50  varieties  and  an
output of around 20 000 tons.   Natural  animal  and  plant  varieties
account for 80%  and  synthetic  varieties  account  for  around  10%.
Domestic products are resistant to water, static electricity and stain
and have comfortable feel. However, varieties with  features  of  mold
resistance, leveling and perspiration fastness,  especially  varieties
  with  good  feel  of  mercerization,   are  still  in  short  supply.
Satisfactory greasing agents produced in China  in  the  recent  years
include SE, CNS and L-3.
The development priority is  on  synthetic  greasing  agents  based  on
  petrochemicals,   varieties  based  on  sulfites,   sulfonated  oils,
sulfonated fatty acid esters  and  synthetic  esters,   and  varieties
resistant to water, light and electrolyte, biodegradable and wash-proof.
Special attention should be paid to the promotion of medium  and  high
-grade composite varieties with  multiple  functions.   The  demand  of
greasing agents in China will reach 52 000 tons in 2000.
(3) finishing agents
Both the variety and quality of finishing agents produced in China have
a great gap as compared with foreign products.  The  total  output  of
finishing agents is around 15 000 tons, and acrylic varieties  account
for around 70% of the total. Starting to be  produced  in  the  recent
years are polyurethane varieties, polybutadiene  varieties,   silicon-
and fluorine-containing varieties and modified nitro-cotton varieties.
The development priority is on modified acrylic finishing agents, water
polyurethane emulsions, stable nitro-fiber emulsions, organosilicon and
organofluorine modified varieties,  butadiene  varieties  and  various
special varieties. The demand of finishing agents  in  China  will  be
around 46 000 tons in 2000.
(4) special auxiliaries
Special auxiliaries mainly include preserving agents,  soaking  agents,
liming agents and many others. Varieties with a high output  in  China
include degreasing agents and anti-mildew agents.
The development priority is on enzymatic preparations, deliming agents,
degreasing agents, liming agents, anti-mildew agents, depilating agents,
auxiliary tanning agents, leveling agents,   neutralizi