Coating Figure Out - hay

Applied Polymer Research Institute

Technology Trends in Automotive Surface Coatings

Jong Myung ParkBuhmwoo Institute of Tech

November 15, 2006


CONTENTS

Pretreatment System

Electro-Coat

Pre-sealed System

Pre-primed System

UV-Curing System

Conclusion

Introduction

Basics of Organic Coating System


환경친화성경량화 안정성 내구성가공성

자동차 강판요구성능

적용 기술

•DP

(Dual Phase)

•TRIP

(Transformation Induced Plasticity)

경량화 및 강도 ,

연신율 우수

고속 충돌성 우수한 고강도 강판

•BH STEEL

Bake hardening steel 약자로 , 차체 성형시 강도가 낮아 가공성 우수하고 , 성형 후에는 자동차 도장공정을 거치면서 받는 열에 의하여 강도가 증가되어 최종 자동차 완성된 이후 높은 강도 구현 가능 .

고내식성

표면처리 강판

•Presealed •Preprimed

•Pre-finished

•Pb,Cr-free

표면처리 강판

• 고강도강 사용으로 차체무게 감소 – 연비 감소로 인한 환경오염 배출물질 감소

Introduction

The Technology of Properties for Automotives


Purpose of Coatings for Automotives

Protect from

미관 상품성 향상

방 청

방 음

입체감

평활성

광택감

색

채

SUN LIGHT(UV, IR)

Water, Oxygen

Sand, Dust

Gum, Soot

Sea breeze

Exhaust gas

Improve

Introduction


Coating Process of Car Body

Introduction


Higher QualityHigher Quality

1.Appearance and Durability2.Color and Corrosion resistance

1. Cut-down Production Process2. Save Labor Usage

Lower Cost

1. Lower Paint Usage2. Reduce VOC3. Reduce Waste Water

EnvironmentalCompliance

1. Direct Coating on Steel Sheet2. Co-work Automotive & Steel Company

ShorterDevelopment

Times

Global Automotive Paint Driving Force

Introduction

Applied Polymer Research Institute코팅 시스템 개론

일반적 코팅 구성 성분

Resin

Adhesion & Film formation

Key Ingredient for performance

Solvent

Rheology control

Solvation & Dilution

Drying behavior

Additive

Defoaming

Rheology control

Surface wetting/levelling

Pigment

Surface protection

Special function

Decoration/Color

Protection

Functionality

Decoration

(Automotive, Heavy-duty,

PCM, Industrial)

UV protection


코팅용 수지

Applications

- Automotive Refinish

- Architectural (Emulsions)

- Vacuum Metallizing, NC

Binder = Film Former = Polymer = Resin

* Thermo-plastic Resin ( 열가소성 )

- High Mw Polymer 에 의하여 생성

- No Functionality for Crosslinking

- Low-solid System

- Solvent Evaporation 에 의하여 도막 형성

- Solvent 및 Heating 에 의하여 재용해 특성

- Latex – Aqueous Acrylic Dispersion

- High VOC System

소재 표면에 접착 및 부착되어 Film Formation 및 형성된 필름의 물성을 좌우하는 가장 중요한 코팅 성분

Characteristics

- Quick Drying

- No Chemical Change

- Re-dissolved

Applications

- Automotive OEM

- Can Coatings

- Coil Coatings

- Appliance Finishes

- 2K PU Coatings

* Thermo-setting Resin ( 열경화성 )

- Low Mw Polymer

- Crosslinking System

- Crosslinker 와 반응할 Functional Group 필요

- Solvent 및 Heating 에 의하여 재용해 어려움

- Acrylics 및 Polyester, Alkyds, Epoxies 등

- Lower VOC System

Characteristics

- Heat System

- Chemical Change

- Not Easily Re-dissolved


Resin Crosslinking

수지의 Reactive Functional Groups 과 Crosslinker 간의 화학적 반응에 의하여 생성되는 3 차원 Polymer Network

* Crosslinking Technology 장점

- Low Mw Resin --- Easily Soluble

- High Solids Level 가능

- 범용적인 다양한 수지 및 경화제 군

- Heat 조건에서 용해되지 않음

- 우수한 Solvent Resistance

- Low Mw 로 인하여 Compatibility 양호

* Crosslink 위한 화학 반응

- Oxidation

- Melamine Crosslink

- Isocyanate Crosslink

- Epoxy Crosslink

Resin Functionality Crosslinkers

Hydroxyl Group (-OH)

Carboxyl Group (-COOH)

Epoxies

Unsaturated Fatty Acid

Amino Resins / Poly-isocyanate

Amino Resins / Epoxies

Polyamines / Poly-carboxylic Acid

Oxygen


코팅용 수지 구분

Thermosetting Resin

Air-drying

2-K Reactive

Baking Type

Stand Oil/Bodied Oil

Varnish (Oleoresinous Varnish)

Ambient Dried Alkyd Resin

Polyurethane Resin

Epoxy Resin

Alkyd Resin

Polyester Resin

Thermo-setting Acrylic Resin

Melamine Resin

Phenol Resin

Blocked Isocyanate

Urea Resin

Thermoplastic Resin

Cellulose (NC & CAB)

Chlorinated Rubber

Thermo-plastic Acrylic Resin

Vinyl Resin


구성 성분 Acrylic Monomer

Initiator

Organic Solvents

Emulsifier

Properties Versatile / Durable

Good Color

Gloss Retention

Good Resistance

- UV

- Hydrolysis

- Oxidation

Characteristics Solvent Composition

Molecular Weight

Tg

Solubility

Uses Automotives

Heavy Industries

Industrials

Architectures

Special Applications

Acrylic Resin

코팅 시스템 개론


Acrylic Resin Crosslinking Reaction


O

OHO

OH

OH

O N

CH2OR

(ROCH2)2N

O NR

N O

O O

H H

OCN R NCO

OH

Epoxy

I socyanate

Amino-Formaldehyde


Amino Resin


Urea / Melamine

Formaldehyde

Alcoholic Solvent

Brittleness

High Speed Cure

Self-condensation

Mineral Spirits Tolerance

Alkoxy Type & Degrees

Solubility & Compatibility

Stability

Cure Rate

Acrylic Polyol

Polyester Polyol

Alkyd

Special Applications

Raw Material Characteristics

Properties Uses (for Crosslink)


NH2

O

H2N C

OH

NH

N

N

N

NH2NH2

NH2

C

O

CH H HOCH2OH HCHO HOCH2O(CH2O)nH

H2N

(Urea) (Amine) (Imide)

(Melamine)

, + n

(Formaldehyde) (Para-Formaldehyde)

NH2

O

CH2N

O

CH H

O

CH2N

H

NCH2OH

NH HOCH2N NCH2N OH2

NCH2OH HOR NCH2OR OH2

+

(Formaldehyde) (Methylol Urea)

+ +

(Urea)

(Imino±â) (Methylol±â) (Methylene Bridge)

+ +(Methylol±â) (Alcohol) (Alkoxy±â)

Amino Resin 반응 메커니즘


Polyester Resin


Acid

Alcohol

Solvents

Flexibility

Good Adhesion

Good Chemical Resistance

Solvent Composition

Molecular Weight

Industrials

Pre-coated Metal

Heavy Industries

High Crosslinking Density Automotives

Raw Material

Properties

Characteristics

Uses

Good Hardness


Polyester Resin 반응 메커니즘


OHH2C

H2C OHn + HOOC COOHn

ethylene glycol

terephthalic acid

OH2C

H2C O C

O

C O

O n

+ 2nH2O

polyethylene terephthalate

ISOCYANATE CROSSLINKS WITH HYDROXYL RESIN

N

O

CN

HR

O

ECAP ISOCYANATE

R N C O

-

CAPROLACTAM

N

HO

+ R' OH R N

C

H

OO

R'POLYESTER RESIN

URETHANE

CAPPOLY.CW210/96

OCN CH2 N N CH2 NCO

O

O

OR

SELF BLOCKED IPDI

CROSSLINKERS FOR CARBOXYL RESINS TGIC , PRIMID & EPOXY

HO

N C

O

(CH2)n C

O

N

HO

OH

OH

TGICPRIM.cw2

10/96

CH2 CH

O

CH2

OO

O

N

N

N

CH2

O

CHCH2

CH2

O

CHCH2

TGIC Primid XL552 (EMS)(CIBA)

BASED ON BISPHENOL A AND EPICHLOROHYDRIN

n

O

CH2 CH CH2 O C

CH3

CH3

O CH2 CH CH2

OH

O C

CH3

CH3

O CH2 CH

O

CH2

EPOXY


CH2 CH

O

CH2

OO

O

N

N

N

CH2

O

CHCH2

CH2

O

CHCH2

TGIC

+

R C

O

OH

H2C CH CH2

OO

O

N

N

N

CH2CHCH2

CH2CHCH2

OH

O

C O

R

OHO

CO

R

OH

O

CO

R

PE&TGIC.CW2 10/96

3

TGIC CROSSLINKS WITH CARBOXYL POLYESTER

CARBOXYL POLYESTER

+CH2 CH

O

CH2 O R

HYBRID

PE&EPOXY.CW210/96

2

COH

O

OHOC

OOC

R

CO O

CO O CH2 CH

OH

CH2 O R

R

ROCH2

OH

CHCH2OOC

EPOXY CROSSLINKS WITH A CARBOXYL POLYESTER

CARBOXYL POLYESTER

EPOXY

Polyester Resin 반응 메커니즘



Epoxy Resin


Bis-phenol A

Epichlorohydrine

Solvents

Good Reactivity

Good Chemical Resistance

No Side Products

Solvent Composition

Molecular Weight

Industrials

Heavy Industries

Automotives

UV Sensitivity Floor Coatings

Electronics

Raw Material

Properties

Characteristics

Uses

Good Mechanical Properties


OH C OH

CH3

CH3

+O

H2C CH CH2 Cl

BPAECH(EXCESS)

NaOH

O- Na+

Sodium Phenoxide

H2C CHO

CH2 Cl+ O CH2 CH

OH

CH2 Cl

O CH2 CH

OH

CH2 Cl

NaOH

O CH2 CH CH2

O+ NaCl + H2O

OH C OH

CH3

CH3

BPA

+ NaOH + H2O

O-

CH2 CHO

CH2 O C

CH3

CH3

O CH2 CH CH2

OH

O C O

CH3

CH3

CH2 CH CH2

O

n

Epoxy Resin 반응 메커니즘


OH

È°¼º¼ö¼ÒÈ ÇÕ¹°

BºÎ °¡ ¹ÝÀÀ

O CH

CH2

CH2

OH

Cl

1,3-Chlorohydrin

H2C

O

CH CH2 Cl

ECH

a-ºÎ °¡ ¹ÝÀÀ

O CH2 CH

OH

CH2

Cl1,2-Chlorohydrin

O CH2 CH CH2

O

NaOH

ÆóÈ¯

H2C

O

CH CH2 Cl

ºÎ °¡ , ÆóÈ¯

O CH2 CH CH2

ClO

CH2 CH CH2

O

O CH2 CH CH2

OHOH

°¡ ¼öºÐÇØ

H2O

1,2- Glycol

Glycidylether + NaOH + H2O

°í ºÐÀÚÈ OH

O CH2 CH

OH

CH2 O

ÁÖ¹ÝÀÀ

ºÎ ¹ÝÀÀ


Urethane Resin


Isocyanates

Glycols

Solvents

Good Adhesion

Good Mechanical Properties

High Gloss

Isocyanate Type

Cure Rate

Sealants

Architectures

Industrials

Hardener for Acrylics

Hardener for Polyesters

Raw Material

Properties

Characteristics

Uses

Good Electro-isolation

Easily Gellation

Yellowing


CH3

NCO

NH OCO -------OCC NH

NCO

CH3

Urethane Resin 반응 메커니즘

A) (Prepolymer) + H2O

B)CH3

NH2

NH

OCO --------OCC NH

CH3

NH2

( 중간체 Amine 구조 ) + CO2

↑

상온 경화형

C O

NH

CH3

CH3

NH

NH

NH

OCO------------

OCO------------

OCO

OCO

NH

NH

CH3

NH

C

O

CH3

NH

A + B

2 액 경화형

A)

B)

CH3

NCO

NH OCO -------------OCC NH

NCO

CH3 (Prepolymer)

HO ----------------- OH (Polyol)

----- OCONH NH OCO -------

CH3

n

A + B



Pigments 구분 및 역할


도막형성 물질과 혼합되어 , 색상과 은폐 , 투명성 제공 및 기후와 부식에 대한 저항성 , 도막 강화 기능 등 부여

Pigments

Titanium Dioxide

Prime Pigment

Extender Pigment

High Refractive Index (Scatter Light)

High Cost

Organic & Inorganic (Oxides)

Calcium Carbonate, Talc, Clays

Barium Sulphate, Silicas

* Reactive Pigments

(Rust Protection – Passivation)

- Borates

- Chromates

- Leads

- Molybdates

- Phosphates

- Silicates

* Barrier Pigments

- Talc

- Aluminum

- Mica

- Silver Paste

Organic pigment

Organic pigment

Property Inorganic pigment

Inorganic pigment

Polarity non polar polar

Surface area large small

Particle size small large

Color

Shade

Transparency

Hiding Power


Pigment Dispersion


Dispersion

Flocculation

Primary Particle

(Ideal Dispersion)

Agglomerate

Flocculate ( 고체 / 기체 )

Flocculated ( 고체 / 액체 ) Deflocculated ( 고체 / 액체 )

Wetting Dispersing Stabilization

Coating System Stabilization Mechanism

Solvent-Based Steric Hindrance / Charge

Water-Reducible Charge / Steric Hindrance

Emulsion Charge Stabilization

Repulsion Attraction


Solvents 역할


수지 및 기타 원료의 용해 , 원활한 작업 위한 점도 조절 그리고 코팅 안정성 및 흐름성 조절 용도로 사용

Evaporation Rate

Solvent Diffusion

Solvent Activity

Characteristics

Viscosity

Diffusion Ratio

Density

Water Solubility

Electrical Resistance

Total Cost in Use

Right Solvency for the Application

Evaporation Rate

Issues

HAPs, VOC Regulation Compliance

Odor & Toxicity

Solvents

Active Solvents

Latent Solvents

Diluent Solvents

Dissolve Resin

True Solvent for NC

Lower Viscosity

High Cost

Assist the Active Solvents

Reduces Viscosity

Poor or Non-solvent Alone

Intermediate Cost

Diluents the System

Non-solvent

Low Cost

Ketones / Esters

Glycol Ethers

Glycol Ether Esters

Alcohols

Water

Aromatic Hydrocarbons

Aliphatic Hydrocarbons


Dissolve Film Formers

Paint Removers

Cleaning Metals

Cleaning Fluids

Coalescing Aids

Uses

Solvent Type Aromatic HC Alcohol Ester KetoneP-series

(Dow)E-series

(Dow)

Typical Solvent Xylene IPA or ButanolN-BuAc or

n-BuPrMEK or MIBK PM or PMA EE or EEA

Resin Solubility

(Acrylics)Good Poor Good Excellent Fair Fair

Resin Solubility

(Epoxies)Good-Fair Poor Good Excellent Fair Good-Fair

Evap. Rate Mid Fast Fast-Mid Fast Mid-Slow Mid-Slow

Odor Poor Good-Fair Fair Poor Good-Fair Good-Fair

Toxicity Poor Good Good Fair Excellent Poor

Regulatory

CompliancePoor Good Excellent Fair Excellent Poor

Solvents 비교



코팅용 Solvents


Solvent-based Water-based

WaterborneWater reducibleHigh solidsConventional coatings

ResinResin

Active solventActive solvent

SolventSolvent(Dilutant)(Dilutant)

ResinResin

CouplerCoupler

WaterWater

ResinResin

Active solventActive solvent

SolventSolvent

ResinResin

WaterWater

CoalescentCoalescent

Coatings

Organic Loving Water Loving

Alkyl Portion Glycol Head

CH3CH2CH2CH2 O CH2CHOH

CH3

CH3

CH3O CH2CHOCH2CHOH

CH3

Alkyl PortionGlycol Head

DOWANOL PnB

DOWANOL DPM

Solvent Partitioning


Additives for Coatings


Additives

Dispersants

Wetting Agent

Defoamer

Control to Pigment Particle Sizes

Pigment Stabilization

(Electrostatic & Steric Stabilization)

Thickener

UV Stabilizer

Control to Surface Tension

(Silicone & Fluoro Chemistry)

Control to Foam

(Waterborne System)

Control to Viscosity

(ASE, HASE, HEUR, Bentone, Cellulose)

Protection to UV Ray

(Hydroxyphenyl triazine, Benzotriazole )


Lower molecular Higher molecular

Wetting Agents 특성


Wetting Agents

Anionic Surfactant

Cationic Surfactant

Amphoteric Surfactant

Hydrophobic Group with Hydrocarbon

12-18 Alkyl Group with –COOH, -SO3H, -OSO3H

-COONa, -SO3Na → Salt Shape

Non-ionic Surfactant

Hydrophilic Group with Cation

-CH2N+CH3Cl-

Surfactant with Anionic and Cationic both

R1-(NH-CH2CH2)2-NH+-CH2-COO-

Non-ionic System

Polyethylene Oxide Compound

––

––––

–– –

Ionic Type Non-ionic Type

With Additive Without Additive


Surface Tensions

80

70

60

50

40

30

20Xylol

Water

White spirit

Melamine resins

Alkyd resins

Acrylate

Resins

Phosphatizedsteel

Untreated steel

SMC-Polyester

mN

/m

Solvents Resins Substrates

aqueous

Surface Tension


Levelling additives


Defoaming


Hydrophobicparticles

Foam lamella

Polydimethylsiloxanes

compatible incompatible

2 - 30 45 - 230 1800 - 2900380 - 1500

DefoamingFlow Slip Hammertone

x

(CH3)3 Si O Si O Si (CH3)3

CH3

CH3 x

No Defoamer with Defoamer


Thickener (Rheology)


newtonian: = const.

pseudoplastic: = f(D)(shear thinning)

visc

osi

ty

shear rate D

Viscosity Curve

shear rate D

visc

osi

ty

= f (time t)

Thixotropy

Flow cup 4 mm ICI cone/plate

Brookfield

storage

leveling

settling sagging

transportation production

stirring application

Rotational viscometer

0,1

viscosity (Pa·s)

0.01 0.1 1 10 100 1000 100000.001

shear rate D (1/s)

100

10

1

Viscosity Profile


UV Stabilizer
