New prospectsforcuringpaint at lowtemperatures...2014/11/04 · PVC -Gelation oven (for high bake...

1 Automotive Circle International presentation

New prospects for curing paint

at low temperatures

Dr. Lothar Kahl, Coatings Raw Materials,

Bayer MaterialScience AG

Dr.-Ing. Matthias Harsch,

LCS Life Cycle Simulation GmbH

Car Body Painting 2014

31st Workshop

November 4th 2014

New Prospects for Curing Paint at Low Temperature

Dr. Lothar Kahl, Coatings Raw Materials,

Bayer MaterialScience AG

Dr.-Ing. Matthias Harsch,

LCS Life Cycle Simulation GmbH

Outline

Page 3 • Dr. Lothar Kahl • Coatings Raw Materials • 2014.11

1. Specific characteristics of polyurethane technology

2. Thermo-latent hardener technology for cross-link efficiency

3. Options for low temperature paint processes

4. Life Cycle Analysis for process and material

5. Process comparison

6. Soft facts beyond hard facts

7. Summary and outlook

Importance of 2K-Polyurethane for Coatings

� Hardness, elasticity and resistance byurethane structure and hydrogen bonds


� High reactivity and full cross-linkingeven at low temperature curing

http://www.bayercoatings.de/bms/db-rsc/bms_rsc_cas.nsf/id/COEN_Self-healing_coatings

Standard OEM Painting Process

Cooling zone

Cooling zone

Clear coatspray booth

Cooling zone

Electrodeposition coating (EDC)

Sanding of primer

Airconditioning

Pre-treatment

Sanding

Primer surfacer spray booth

Flash-off

Cavitypreservation

Touch-upspray booth

Base coatspray booth

Touch-upoven

Exhaust aircleaning

Sealing + underbodyprotection

EDC

Oven

Primer surfacer

Oven

Top coat

Oven

180 °C

160 °C

140 °C

© Dürr Systems GmbH

Inspection + Touc-up


PVC gelation

Oven120 °C

• strong increase of reactivity >75°C

• inorganic tin-compound

• catalytic central atom electronically protected by donator group

• high stability in PU hardener solution

A New Technology of Thermolatent Reactivity

Page 6

� Speed of paint hardening determins the paint-line efficiency

� Seperation of film formation and hardening improves appearance

� Thermolatent reactivity for paint flow and high line effi ciency

• Dr. Lothar Kahl • Coatings Raw Materials • 2014.11

0

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50

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70

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15 20 25 3020

40

60

80

100

120

140

160

180

200

0 1 2 3 4 5

DBTL (500 ppm Sn)

Standard line material

Non catalyzed

State-of-the-Art 2K-PU-Plastic ClearcoatReaction after Mixing and at 80 °C (lab oven)

Reaction in solution after Mixing @ 23 °C (Pot-life)

Pendulumdampening [sec]

Time[min]

Curing@ 80 °C

(10 min RT, x min 80 °C, 60 min RT)

Efflux Time ISO 4 Cup [sec]

Time[h]

Equal concentrationof tin on hardener solids


Indication for good flowand high appearance

Indication for high cross-link

*) DBTL: standard state of the art catalyst without thermo latent properties

DBTL (organic Sn)

0

10

20

30

40

50

60

70

80

15 20 25 3020

40

60

80

100

120

140

160

180

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0 1 2 3 4 5

DBTL (500 ppm Sn)

Thermolatent Catalyst(500 ppm Sn)Standard line material

Non catalyzed

Thermolatent Hardener TechnologyReaction after Mixing and at 80 °C (lab oven)

Reaction in solution after Mixing @ 23 °C (Pot-life)

Pendulumdampening [sec]

Time[min]

Curing@ 80 °C

(10 min RT, x min 80 °C, 60 min RT)

Efflux Time ISO 4 Cup [sec]

Time[h]



*)

Indication for good flowand high appearance


DBTL (organic Sn)


Thermolat. Hardener(in-organic Sn)

Thermolat. Hardener(inorganic Sn)

The Ideal Process:Thermolatent Hardener Technology

Low reactivity: optimum flow and leveling

Temperature

High reactivity: fast curing


2K-PU Clear CoatProgress of Cross-linking at 80 °C

80 °C

Organic tinFrom DBTL**)

Inorganic tin fromthermolat. hardener

140 °Coven temp.

no catalyst

no Sn

after application

after oven curing (20 min)+ 1 day norm climate **)

+ 2 days norm climate **)



**) 25°C, 50% rel. humidity




2K-PU Clear Coat

Progress of Cross-linking at 100 °C

100 °C

Organic tinfrom DBTL

Inorganic tin fromthermo lat. hardener

Rel

ativ

e co

nten

tofi

socy

anat

egr

oups

%

140 °Coven temp.

no catalyst

no Sn

!!!


**) 25°C, 50% rel. humidity*) DBTL: standard state of the art catalyst without thermo latent properties


Boundary of Surface Temperature


Inorganic Sn in thermolatent hardener

90°Ctarget

under-baking over-baking

Low temperature concept

100°C80°C

Clear coat oven today

140°C

target

2K-PU clear coatwithout catalyst


Boundary of Surface Temperature


• Functional principle of thermolatent hardeneris proven at plastic coating system

• Adaptation of high temperature coatings (> 140°C)to a 90°C paint formulation to be developed in 2015

- Painting / curing equipment- OEM pilot serious- Investment and SOP

From Chemicals to Painted Car Body

….. 3 years + ….

- R&D new monomers- New resources

- Polymer synthesis / testing- Industrialization

- Paint formulation / testing- OEM tests and approval

….. 1 years + ….

….. 2 years + ….

….. 4 years + ….

§§

§

TSCA

KECI

IECSC…….Page 14 • Dr. Lothar Kahl • Coatings Raw Materials • 2014.11

Status of thermo-latent formulated hardener

Cross-functional Project TeamExploit Low Temperature Potential

- Contract car manufacturer

- Equipment supplier

- Paint expert

- Fraunhofer Institute for Manufacturing Engineering and Automation

- LCS Life Cycle Simulation GmbH

- Automotive project management support

- Coatings Raw Materials


Detailed process evaluation with industry experts

EVALUATED LOW BAKE PROCESSES(AFTER ELECTRO COAT)

3 coat – 1 heated flash-off – 2 bake

PSw/b Oven (bake)160 °C

Heated flash off (hf)

2K CCs/b Oven (bake)

140 °CI/A E

BCw/b

A E

BCw/b

A E

BCw/b

I HRZA E

High bake - Basis A: 160 / 140 °C - process

2 wet – 1hf – 1 bake

Heated Flash Off

(hf)

2K CCs/b Oven (BAKE)

140°C

I/A E

BCw/b

A E

2 K BCw/b

A E

BCw/b

I HRZ

High bake - Basis B: 140 °C process

Basis A

Basis B

A = ExteriorI = InteriorE = Electrostatic application (bell)HRZ = High rotation atomizing

without high voltage w/b = Water borne paints/b = Solvent borne paint

Explanation

EVALUATED LOW BAKE PROCESSES(AFTER ELECTRO COAT)

3 coat – 1 heated flash-off – 2 bake

PSw/b Oven (bake)160 °C

Heated flash off (hf)

2K CCs/b Oven (bake)

140 °CI/A E

BCw/b

A E

BCw/b

A E

BCw/b

I HRZA E

High bake - Basis A: 160 / 140 °C - process

2 wet – 1hf – 1 bake

Heated Flash Off

(hf)

2K CCs/b Oven (BAKE)

140°C

I/A E

BCw/b

A E

2 K BCw/b

A E

BCw/b

I HRZ

High bake - Basis B: 140 °C process

Basis A

Basis B

Step 1

Step 2

Step 3

Step 4

Oven (bake)90 °C

2K PSw/b

Oven (bake)90 °C

Heated flash off

Heated flash off

2K funct. jayer

Oven (bake)90 °C

Oven (bake)90 °C

Oven (bake)90 °C

2K BCw/b

2K PSw/b

2K funct. jayer

Low Temperature Process Option (after PVC )Type „B1B2 / IPP / 2010V / 3C1B“

Cooling zone

Solvent 2K-PU Clear coatspray booth

Cooling zone

Pre-treatment

Sanding

2K-PU Pre-coat spray booth

Flash-offWater 1K-PU Base coat

spray booth

Touch-upoven

PVC Sealing+ underbody protection

Top coat

Oven< 100 °C


„optional“

EDC

Oven180 °C

PVC

Oven160 °C

Cavitypreservation

Touch-upspray booth


Electro Deposition Coating


Low Temperature Process Option

type „VW 2010“ (with PU underbody protecion )

Cooling zone

Solvent 2K-PU Clear coatspray booth

Cooling zone

Electro Deposition Coating

Pre-treatment

Sanding

Flash-offWater 2K-PU Base coat

spray booth

Touch-upoven

2K / 1K-PU Sealing+ underbody protection

Top coat

Oven< 100 °C


„optional“

EDC

Oven180 °C


Cavitypreservation

Touch-upspray booth



Paint line

Paint as well as equipment technology and investment costs are based on newest paint shop (state of the art) located in China, because there are the newest greenfield plants.

Paint line with dry seperation for overspray and recirculation of process air

Exhaust air cleaning of clear coat spray booth

Scenario (energy mix, energy costs) Germany and China with identical paint shops at both locations

line capacity: 33 jph gross with 30 jph net (final out-put per hour)

3-shift operation

6.750h/year operation time

202.500 cars per year

Evaluated paint processes and process steps

The process steps after EDC are considered and evaluated in detail. Underbody protection and sealant are maintained as fixed unchanged process part, due to lack of real cost effective technology alternatives today. Changes are shown on visionary basis.

Painting steps and curing is described in detail in "Low Bake Painting Process" (Dürr, M. Zabel)

Process variants are described after underbody protection and sealants with the following layouts:

Standard process A: High temp. curing with primer surfucer (3wet - 2hf - 2 bake): PS 160°C, CC 140 °C

Standard process B: Volkswagen Process 2010 (primerless) (2 wet - 1 hf - 1 bake, 140°C)

Step 1: Decrease temperature for curing primer surfacer (160°C change to 90 °C) and clear coat (140°C change to 90 °C).

Step 2: Functional layer with heated flash-off instead of fully cured primer surfacer (comparable to: GM Orion plant (USA), Mercedes Rastatt plant (Germany), Toyota Woodstock plant (Canada))

Step 3: w/o flash-off after pre-zone (process similar to new VW / BMW plants in China)

Step4: w/o pre-zone coating and w/o primer surfacer, similar to VW process 2010

Premises of Process Descriptionsand Calculations - 1 -

… based on newest paint shop (state of the art) …

… (energy mix, energy costs) Germany and China …..

… process steps after EDC …..


Premises of Process Descriptionsand Calculations - 2 -

Process data: Oventemperatur (car surface temperature):

Standard high temp.: 160 °C for primer surfacer and 140 °C for Clear Coat

Low bake temp: 90°C (80°C under-baking and 100°C over-b aking)

Details: Comments Temperature Time

EDC not considered for any changes; maintain as standard for all process variants without specific figues / calculation

Underbody protection / sealants PVC-oven (for high bake Basis B, low bake step 1 - 4 160°C 15 min. heating-up; 15 min. maintain; 12 Min cool-down

PVC-Gelation oven (for high bake Basis A) 120°C 8 min. heating-up; 7 min. maintain; 6 Min. cool-down

Primer surfacer / Functional layer / pre -zone coating: Standard primer surfacer 160°C 15 min. heating-up; 20 min. maintain; 8 min. cool-down

Low temp. Functional layer / pre-zone coating: flash-off

70°C 5 min. warm blowing; 3 min. cool-down

Low temp. Functional layer / pre-zone coating: Oven 90°C 10 min. heating-up; 20 min. maintain; 5 min. cool-down

Base coat : Flash-off 70 °C 5 min. warm blowing; 3 min. cool-down

Clear coat: Standard 140 °C 16 min. heating-up; 20 min. maintain; 10 min. cool-down

Low Temp. 90 °C 10 min. heating-up; 20 min. maintain; 5 min. cool-down

Process evaluation:

type of car

Mid-class (e.g. VW Golf, BMW 1, Mercedes A-class, Toyota Corolla

Determination of colors (important for base coat fo rmulation)

silver metallic and solid white (metallic 60% / solid 40%)

Evaluation criteria:

Detailed evaluation of paint material (amount, value); investments (costs); energy (consumption of primary energy, value); sustainability (consumption of resources, emissions of solvent, CO2 and green-house gas)

… 90°C (80°C under-baking and 100°C over-baking) …

… paint material …. investment … energy ….. sustainability …)


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LIFE CYCLE POTENTIAL ANALYSIS- Low temperature processes -

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Goal and scopeDefinition of system boundaries

pain

t and

pro

cess

mat

eria

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lus

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uppl

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reso

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recy

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fe(o

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reg

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to s

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and

over

spra

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emis

sion

s

system boundary for life cycle investigation

car bodye-coated

car bodycompletely coated

use and End-of-Lifeoutside of system boundary

productionoutside of system boundary

system boundary for gate to gate investigation

High bake- Basis A 3 coat - 1hf - 2bake

High bake- Basis B 2 wet – 1 hf – 1 bake

Low bake - Step 1 3 coat – 1 hf – 2 bake

Low bake - Step 2 3 wet – 2 hf – 1 bake



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Boundary conditionsDocumentation material demand (example)Calculation procedure for material demand

Process 3coat-1hf-2b (Basis - high bake A)Process parameter (paint application)FU = Funktional Unit, i.e. one ok painted car body

Primer BC met silver BC uni white CCdensity dry paint film [g/cm³] 1,5 1,2 2,0 1,1

paint solids [%] 52,0 20,0 48,0 60,0paint VOCs [%] 6,0 15,0 12,0 40,0

painted area interior [m²] 8,0 8,0 8,0 8,0 VW Golf VIIpainted area exterior [m²] 9,0 9,0 9,0 9,0 VW Golf VII

layer thickness interior [µm] 0 10 15 25layer thickness exterior [µm] 35 15 22 40transfer efficiency interior [%] 60 60 60 60 bell

transfer efficiency exterior [%] 70 57 70 70 bellpaint consumption interior [kg/FU] 0,000 0,800 0,833 0,611

paint consumption exterior [kg/FU] 1,298 1,421 1,179 0,943rinsing losses paint [kg/FU] 0,045 0,347 0,347 0,076paint consumption [kg/FU] 1,343 2,568 2,358 1,630

repair/second run [%] 10,0 10,0 10,0 10,0repair/second run kg/FU] 0,134 0,257 0,236 0,163

total paint consumption [kg/FU] 1,477 2,824 2,594 1,793distribution metallic to uni 60% 40%

total consumption BC [kg/FU] 1,695 1,038

Process parameter (rinsing)consumption rinsing material [kg/FU] 0,329 1,836 1,836 0,592

VOC content [%] 10% 10% 10% 100%

Source (all rinsing operations): Dürr Systems GmbHPaint rinsing losses - long-lasting rinsing 1K 1K 2K switch paint system (1K or 2K)

Primer/Pre paint (1K/2K) BC (1K/2K) 2K-CCrobot number 4 14 12

Paint rinsing losses ml/Rob and color change 45,0 45,0 60,0 thereof app. 95% recycling + 15 ml HN when 2Kpaint block size each x car body 5 2 10

Paint rinsing losses ml/FU 36 315 72density paint (appl.) g/cm³ 1,25 1,1 1,05

long-lasting rinsing

Rinsing material - long-lasting rinsingPrimer/Pre paint (1K/2K) BC (1K/2K) 2K-CC

robot number 4 14 12Rinsing material ml/robot 150,0 150,0 200,0 thereof app. 90% recycling + 50 ml HN when 2K

frequency each x car body 5 2 10

Rinsing material ml/FU 120 1.050 240

Rinsing material - short rinsingPrimer/Pre paint (1K/2K) BC (1K/2K) 2K-CC

robot number 4 14 12Rinsing material ml/robot 15 15 15 all into spray booth

frequency each x car body 5 2 10Rinsing material ml/FU 12 105 18

Rinsing material - spraye r cleaningPrimer/Pre paint (1K/2K) BC (1K/2K) 2K-CC

robot number 4 14 12Rinsing material ml/robot 500 500 500 all for recycling

frequency each x car body 10 10 15Rinsing material ml/FU 200 700 400

tota l ml/FU 332 1.855 658density rinsing material g/cm³ 0,99 0,99 0,90

thereof recycled ml/FU 308 1.645 556% 92,8% 88,7% 84,5%

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0

100

200

300

400

500

600

700

800

900

High bake A

High bake B

Step 1 Step 2 Step 3 Step 4Pri

mar

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gy

in k

Wh

pe

r o

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pain

ted

car

bod

y

End-of-Life

rinsing material

CC

BC

Pr/pre paint

seam sealing

gas (PE)

gas (dir)

hot water (PE)

hot water (dir)

power (PE)

power (dir)

100,0% 84,8%88,4% 96,8% 93,9% 88,8%

ResultsPrimary energy demand (with PVC for underbody protection / sealant)System boundary: life cycle (ok painted car body, cradle to grave )

(PE): Includes direct energy transformation(dir): Direct power consumption in process

Energy mix Germany

Color sharemetallic: 60%uni: 40%

Clear Coat

Base CoatPrim. Surf./Pre-Coat

UBC / sealant

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-100

0

100

200

300

400

500

600

700

800

900

High bake A

High bake B

Step 1 Step 2 Step 3 Step 4Pri

mar

y e

ner

gy

in k

Wh

pe

r o

.k.

pain

ted

car

bod

y

End-of-Life

rinsing material

CC

BC

Pr/pre paint

seam sealing

gas (PE)

gas (dir)

hot water (PE)

hot water (dir)

power (PE)

power (dir)

100,0% 73,8%88,4% 85,8% 82,9% 77,8%

ResultsPrimary energy demand (with 2K-PU for underbody protection / sealant)System boundary: life cycle (ok painted car body, cradle to grave )

Energy mix Germany

Color sharemetallic: 60%uni: 40%

Clear Coat

Base CoatPrim. Surf./Pre-Coat

UBC / sealant

(PE): Includes direct energy transformation(dir): Direct power consumption in process

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ResultsLife Cycle Optimization Potential (with PVC for UBC / sealant)

1.258 tons crude oil equivalents per year

48 oil trucks á 26t net load per year

3.076 tons CO 2 equivalents per year

26 Mio. km at 120g CO 2 per km

Boundary condition: yearly plant operation, 200.000 painted car bodiesSaving potential (difference High bake A to Step 3):

Energy mix Germany

Process Comparisonreferred to Process Basis A

high bake UBC/sealantwith PVC

low bake UBC/sealantwith PU

% kg

% kWh

% kg

kgkWh

� Low bake process supports sustainability in nearly all aspects


� Material saving especially in low bake UBC / sealant case (PU)

Process Comparisonreferred to Process Basis A

high bake UBC/sealantwith PVC

low bake UBC/sealantwith PU

% €/car

% €/line

% €/car

% €/car

€

� Less costs for investment and energy especially in case of low bake UBC / sealant

� Cost for higher performance paint compensate savings in energy and invest


Soft facts for Low Bake Paint Process (1/2)

• Shorter Heat-up- (to 90°C) and cool-down-time give fur ther degree of freedom, e.g. optimization of paint flow (appearance), better heat-up-control of multimaterial car body , ……

• The lower the max. temperature the easier is the controlability of the car mix (e.g. convertibles and standard limousines, small and la rge cars)

• Plastic in-line painting - Same high-performance surface of plastics and metal- better color match / color harmony- same paint for metal and plastics

• More freedom of design with plastics: - design of hang-on parts- sophisticated special colors / personaliation of cars


• Better implementation of lightweight car conceptsin mass paint lines

• Over-baking at 100°C is less critical for paint and plastics than at 170°C

• Other sources for heat and cold can be used (district heat, solar energy, power-heat cogeneration („Kraft-Wärme-Kopplung“), waste heat utilization fromother processes, ………)

• Better positioning of cars in sustainability aspects

Soft facts for Low Bake Paint Process (2/2)


• Paint reactivity contolled by thermolatend hardener technology allows low temp. processwithout loss of productivity

• Results of process comparison depend strongly on reference process

• A low temp. process support sustainability strategies and has significant reductionsin energy consumption and CO2-emissions

• Further opportunity for sustainability with low bake UBC / sealant

• Low temperature paint process supports OEM with

- Lightweight and multimaterial car concepts- Inline-painting of plastic parts- consideration of renewable energy

Summary

• Thermolatent hardener availible for testing to the paint industry in December 2014

• Specific low temperature paint formulations to be developed in 2015

• Low bake processes can be implemented step-wise in brown-field plants

• The optimum in performance and cost efficiency will be realized in specific designed green-field plants

Outlook


AcknowledgementsPhilipp RuckerKarl Schablas

Frank HerreMichael ZabelWolfgang Tobisch

Dr. Karl-Friedrich Dössel

Dr. Michael Hilt

Dr. Matthias Harsch

Prof. Dr. Hans JungSebastian DistererDetlef Eitel


Forward-Looking Statements

This presentation may contain forward-looking statements based on current assumptions and forecasts made by Bayer Group or subgroup management.

Various known and unknown risks, uncertainties and other factors could lead to material differences between the actual future results, financial situation, development or performance of the company and the estimates given here. These factors include those discussed in Bayer’s public reports which are available on the Bayer website at www.bayer.com.

The company assumes no liability whatsoever to update these forward-looking statements or to conform them to future events or developments.


Thank you!

New prospectsforcuringpaint at lowtemperatures...2014/11/04 · PVC -Gelation oven (for high bake...

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Transcript of New prospectsforcuringpaint at lowtemperatures...2014/11/04 · PVC -Gelation oven (for high bake...