Green Technologies for the Leather Production

1

l

Head of Marketing & Sales

Harald Bauer

Global Leather Business

07.09.2010

Green Technologies for the Leather Production

45th Leather Research Industry Get Together (LERIG)

29 January 2011

Confidential

Bu Leather Services


Harald Bauer

BU Leather Services, Harald Bauer, Global Head of Markeing & Sales (Copyright Clariant. All rights reserved.) Slide 2

Agenda

Ecological Leather Production

Tanning

Ecological Update

Retanning, Fatliquoring

Finishing

2


Green Leather – Industry Achievementsin the Past

Wet White tanning as alternative to Chrome tanning

Enzymatic Unhairing process

Continous improvement of chemical exhaustion for the beamhouse, tanning and wet end processes

Complete waterborne finishing replacing solvent systems or solvent/water emulsions

Replacement of hazardous substances (Nonylphenols, Phthalates, Ethylglycol, Dimethylformamide,

cancerogenic azo dyes and aromatic amines, lead chromate pigments, short chain chloro paraffins)

Development of Upgrading technologies for improved raw hide utilization

Continuous chemical reduction in finishing (low pressure spraying, RRC technology)


Stakeholder for the Leather –Manufacturing Process

Environment

EconomyCustomer

Demand

Clariant

Technical

SupportBalance

High Yield – Low Resources

Minimizing Water quantity

Minimizing chemical demand

Minimal chemical and water waste

Minimal leather waste

Maximizing leather yield

High Quality – Low Cost

Leather Quality

Lowest possible cost

Lowest possible risk (hazardous substances)

Fashion, Function

Wearing comfort

High Speed – Low Cost

Lowest production costs

Production speed

Highest production yield

Lowest waste

Lowest chemical and water consumption

3


Green Leather – New Ecological Demands

Chemicals Green chemistry in leather chemicals

Safety Environmental friendly substances, reduction of hazardous substances

Waste Updated leather production with minimized waste and resources

Raw

material

Further development of the manufacturing process with maximizing the

raw material


Green Leather – Examples for new achievements

Water/salt

reduction Process Innovation – New Wet White Tanning Technology

Chemicals Greener Fatliquors and Retanning Agents

VOC NMP free Finishing systems

Yield Modern Upgrading Technologies

4


Agenda


Tanning

Ecological Update


Finishing


Most commonly used mineral free tanning systems

Metal free Tanning

Systems

Phosphonium salts

Glutaraldehyde

Vegetable

Replacement Syntans

Oxazolidine

Oxidisable oil tannage

Silicates

5


Increasing

ecological

demand

Increasing

demand

for chrome-free

Leather

Process

simplification

EasyWhite Tan

Cost reduction

Environmental

awareness

Less scope

for processing

errors

Operator

safety

Environment perspective

Production perspective

Why Granofin® Easy F-90?


Bate

DelimingPickle Tanning Basification Effluent

1 2 3 4 5

Process considered for the comparison

Bate

DelimingTanning Effluent

1 2 3

Wet White

EasyWhite

Tan

Process %Chemical

Time

min

Offer

in Kg

Pickle 40 Water 8000

7 Salt 15 1400

Add 1 Formic Acid 85% 45 200

Add 0,6 Sulphuric Acid 98% 120 120

Tanning 2,7 Glutaraldehyde (25%) 480 540

Basifi. 0,3 Sodium Bicarbonate 20 60

Add 0,3 Sodium Bicarbonate 20 60



Add 3 Phenol Syntan p. 60 600

Total 880 3060

Process %Chemical

Time

min

Offer

in Kg

Tanning 30 Water 6000

10 Granofin F-90 liq 480 2000

Total 480 2000

EasyWhite Tan & Wet White comparison

Wet White EasyWhite Tan

6


I Start pH 8,5 to 7,0 after bating

II Temperature 25°C to 30°C

III Product offer 8% to 10% based on limed /split weight

IV Running time 8 to 12 hours

V Increase temperature after 60-90 min to 30 -35°C

VI Increase temperature after 90-120 min to 40°C

VII Run 6 to 8 hours at 40°C

VIII End pH 4,5 to 5,4

IX Shrinkage temperature 72°C to 75°C

0

1

2

3

4

5

6

7

8

0 1 2 3 4 5 6 7 8 9 10

0

1

2

3

4

5

6

7

8

pH pH

Time

Standard Process

New Process with Granofin Easy F90

Key Points in the Process


Deliming and bating

(~ 4 h / 1 Check)

Pickle

(~ 2-4 h / 2-3 Checks)

Tanning

(~ 8-12 h / 1 Check)

Basification

(~ 2-3 h / 2 Checks)

Deliming and Bating

(~ 4-6 h / 1 Check)

New compact process– no pickle necessary

(~ 8-12 h / 2 Checks)

Environmentally friendly

Lean production process

Less use of chemicals

Reduction of production time

More consistent production quality

Less scope for processing errors

Process focus EasyWhiteTan

Customer Benefits through EasyWhiteTan (Granofin® Easy F-90)

7


Excellent grain flatness

White appearance

Very tight grain

Less neck wrinkles

Good resistance to mould

Shrinkage temperature ~72 C

Cationic Character of Wet White

Suitable for shoe upper and fancy leathers, not only for Automotive and Furniture

Leather Properties

Wet

White

More accurate substance control, compare to Glutaraldehyde and THPS

Less stretch and elasticity

Less wrinkles, flatter growths marks

High Whiteness if required

Very tight grain

Wide range of articles possible

Combinable with metal retanning if necessary (chrome, aluminum or zirconium)

Crust


Conclusion

EasyWhite Tan

opens new

horizons

The technological application of Granofin® Easy

F-90 permits a simplification of the current known

processes

Granofin® Easy F-90 technology is an

environmentally friendly tanning system

Granofin® Easy F-90 is already in production and

being tested at several customers

– All potential applications not yet evaluated

– Further work on optimization of retanning

process – Principal to reduce products used

compare to current production

– Evaluation of products development for the

retanning of EasyWhite Tan

– Results to date extremely promising

8


Agenda


Tanning

Ecological Update


Finishing


Retanning Agents – Ecological Update

Chemistry Eco Target

Retanning

Agent

Synthanes Aromatic base (Phenol,

Naphthalene, cresol etc.) with

sulphonate or hydroxy function

Formaldehyde condensation

Residual content of Formaldehyde

and Phenol of both < 50 ppm

Resins Urea-Formaldehyde

Dicyandiamide-Formaldehyde

Melamine-Formaldehyde

Residual content of Formaldehyde

< 50 ppm

Polymeric Polyacrylic acid

Combination and copolymerisation

with natural substances

Incorporation of renewable (and

biodegradable) raw materials

Tergotan PMB

9


Fatliquors – Ecological Update

Chemistry Eco TargetFatliquors

Natural Sulfated or sulfited natural oils

(castor, neatsfoot, soya)

Long term experience in using

natural oils

Recovered natural oils

Synthetic Alkylsulfosuccinates

Quaternary amines as cationic

fatliquors

Use of by-products as raw materials

Higher exhaustion, lower COD

values for the waste water

Polymeric Polymeric succinates and

sulfosuccinates

Reuse of synthesis waste as raw

materials

Higher exhaustion, lower COD

values for the waste water

Tergotan PO-60


Agenda


Tanning

Ecological Update


Finishing

10

NMP-free Finishing


VOC- volatile organic compounds -

EC Directive 1999/13/EC

- Vapour pressure at 20 C (or at working temperature) over

0.1 hPa

Definition

Europe

Definition

USA

CFR 40, Part 51.100(s), US EPA

- chemical compounds that take part in photochemical

reactions in the atmosphere

Continuous VOC reduction for all processors

Continuous VOC reduction for all (finishing) chemicals

Legislators reducing and making emissions more expensive

11


NMP and VOC

Boiling pointat normal pressure

Vapour

pressure*

Ethanol 78 C 79 hPa

Water 100 C 32 hPa

Butyl acetate 125 C 17 hPa

Butyl glycol 171 C 1.5 hPa

NMP 202 C 0.4 hPa

VOC (EU) > 0.1 hPa

Ethylene glycol 197 C < 0.1 hPa

* CRC Handbook of Chemistry And Physics

NMP is a VOC according to EU and US definitions


NMP – N-methylpyrrolidone –Properties

Chemically stable

Polar solvent – Completely soluble in water

Good miscibility with organic compounds

Aprotic – No reaction with isocyanate

Reduces surface tension

pH-neutral

N

O

CH3

12


Production processAcetone vs. Prepolymer ionomer process

monomers

in solvent

prepolymer

in solvent

prepolymer dispersion

containing solvent

solvent free

polymer dispersion

first

reaction

step

dispersion

with

water

second

reaction

step,

distillation

first

reaction

step

dispersion

in

water

second

reaction

step

monomers

with NMP

prepolymer

with NMP

prepolymer dispersion

containing NMP

polymer dispersion

containing NMP

A) Acetone process

B) Prepolymer ionomer process


NMP as a coalescing agent

Miscible with water and many solvents

Reduces the MFT

Improves flow

Simplifies film formation

Water evaporates

Primary dispersion

Packing of spheres

Packing of rhombicdodecahedrons

Film

Deformation of the

polymer particles

Interdiffusion

Coalescing agent promotes interdiffusion

and dissolutionof boundary surfaces

13


NMP in leatherPartial dissolution of lipophilic substances

H2O

H2 O

DT

Greasing agents

Retanning agents

Dyestuffs

NMP

(Hydro)thermal processes in the

finished leather

Natural ageing processes

Artificial ageing test

Migration into the crust

Partial dissolution of water-

soluble and, above all, lipid-

soluble substances

Promotion of migration to

the (finished) surface


New procedure for NMP-free polyurethane dispersion

Auxiliary agent

Water

Polyol

Isocyanate

Finished PUR

dispersion

14


NMP – Legal developments and measures taken by Clariant

Future

>2010

Further reductions in VOCs

Apr 2005

All standard products

are NMP free

Standard

products

Feb 2004

Complete NMP-free

finishes

1st generation

Oct 2001

Binding agent syntheses

without NMP

Project start

Clariant

International legislation

2001

Addition of NMP

in California to

Proposition 65

EU resolution to

reclassify NMP

End of the transitional period Binding EU classification

2001 2003 2004 2005 … 2010


Topcoats – Highest performancewithout NMP

No difference

between NMP-

containing and

modern lacquers!

Application Application process

Process parameters (Flow, viscosity)

Fastness

Wear properties

Ageing resistance

Soilability

Squeaking behaviour

Aesthetics

and haptics

Cracked grain

Matt / Gloss grade

Depth of black

Feel

15


NMP and VOC content- Priming-

Priming (example recipe)

2002 Amount NMP VOC EU Since 2005 Amount NMP VOC EU VOC USA

PU binder 300 g 5.2% 6.0% PU binder 300 g 0.0% 0.0% 0.5%

Soft PU 50 g 4.7% 8.3% Soft PU 50 g 0.0% 3.5% 4.0%

Acrylate 100 g 0.0% 0.0% Acrylate 100 g 0.0% 0.0% 0.0%

Pigment 100 g 0.0% 0.0% Pigment 100 g 0.0% 0.0% 0.0%

Matting paste 120 g 0.0% 0.6% Matting paste 120 g 0.0% 0.6% 0.6%

Additive 70 g 0.0% 0.0% Additive 70 g 0.0% 0.0% 0.0%

Wax 30 g 0.0% 0.0% Wax 30 g 0.0% 0.0% 0.2%

Water 230 g Water 230 g

Total 1000 g 1.8% 2.3% Total 1000 g 0.0% 0.2% 0.4%


NMP and VOC content- TopCoat -

TopCoat (Example recipe)

2002 Amount NMP VOC EU Since 2005 Amount NMP VOC EU VOC USA

Matting 400 g 7.1% 15.0% Matting 400 g 0.0% 6.3% 6.5%

PU gloss binder 100 g 5.2% 6.0% PU gloss binder 100 g 0.0% 0.0% 0.5%

PU gloss binder 2 80 g 7.0% 8.0% PU gloss binder 2 80 g 0.0% 1.8% 2.3%

Silicon old 60 g 0.0% 35.0% Silicon new 60 g 0.0% 20.0% 21.0%

Isocyanate 60 g 0.0% 20.0% Isocyanate 60 g 0.0% 20.0% 19.8%

Water 300 g Water 300 g

Total 1000 g 3.9% 10.5% Total 1000 g 0.0% 5.1% 5.3%

16


Summary

NMP-free products and finishing systems available with

the same performance

Long-term usability of NMP-related substances is

questionable

Reduction in NMP is not sufficient to meet car and

furniture manufacturers‘ specifications

Elimination of NMP succeeded with concomitant

sustainable VOC reduction

By VOC reduction and NMP Elimination sets a new

ecological standard in finishing

Upgrading

17


UpgradingEconomic Need meets Ecological Benefit

high

low

1980 2011Demand of Premium Leather

Rawhide Quality available

Upgrading

Yield Improvement

Cutting waste reduction

Resource optimization


UpgradingPolishing Grounds

Upgrading of leather with minor grain defects

Maintaining the natural look, low overloading of the grain

For RRC and spray finishes

For full grain and corrected grain

Ironing or polishing, no buffing necessary

Prebase for

– Shoe upper

– Furniture

– Garment

– Fancy Goods

18


RRC Technology

Improvement of filling power and adhesion

Optimized stability at the blade/knife

New product: Melio 06-U-78

UpgradingMicrosphere Technology


UpgradingFurther developments

Strong covering systems without hardening effects of

classical fillers

Improved embossing behaviour

Mechanical and optical properties of binder and filling

materials coming closer

Filler-Binder Hybrids

New Technologies

19

l


Harald Bauer

Global Leather Business

23.01.2011

Thank you very much for your attention

Confidential

Bu Leather Services


Harald Bauer

Documents

Green Technologies for the Leather Production