Coatings and Inks

Dr Ian Maxwell

© The Lubrizol Corporation 2006, all rights reserved

HYPERDISPERSANTS INHYPERDISPERSANTS IN

NANOTECHNOLOGY APPLICATIONSNANOTECHNOLOGY APPLICATIONS

NanoMaterials 07

1st May 2007

Ian Maxwell - Noveon


OUTLINE

• Nano particles / properties / stabilisation needs

• Overview of Hyperdispersants technology

• Solsperse product range – how to choose

• How to use dispersants – milling or surface treatment

• Noveon TS and Development Capability


• Working with particles with sizes between say 5 nm and 100nm

• Working with giant molecules that have some defined shape

– Buckminster fullerene (“Fullerene”)

– Carbon nanotubes

• Molecular Electronics/Molecular computing.

– Processes happening within a single molecule

• Microengineering

– Tiny machines (actually micron, not nanometre sizes)

– “Nanobots”

WHAT IS NANOTECHNOLOGY

Only the first named area probably has

any interest for Noveon Hyperdispersants


Some “nanoparticle” products

5 nm 100nm50 nm

Conventional tinting

pigments

Transparent pigments

Iron oxides, TiO2 based UV absorbers

Ceramics

Sol gel processing conventional/grinding processing

“Quantum Dots”


TYPES OF NANOPARTICLESTYPES OF NANOPARTICLES

MAGNETISMIRON OXIDE

CONSUCTIVITY / MECHANICAL STRCARBON NANOTUBES

CONDUCTIVITY / IR ABSORBANCEANTIMONY TIN OXIDE

CONDUCTIVITY / IR ABSORBANCEINDIUM TIN OXIDE

ANTIMICROBIALMETALS (SILVER)

ANTIMICROBIALSILVER OXIDE

ANTIMICROBIALCOPPER OXIDE

UV ABSORPTION / ANTIMICROBIALTITANIUM DIOXIDE

UV ABSORPTION / ANTIMICROBIALZINC OXIDE

UV ABSORPTION / HARDNESSCERIUM OXIDE

HARDNESSSILICONE CARBIDE

HARDNESSDIAMOND

MECHANICAL STRCLAY

HARDNESSZIRCONIA

HARDNESSALUMINA

HARDNESSSILICA

COLOR / MECHANICAL STRCARBON BLACK

PROPERTYMATERIAL


• The smaller the particle, the shorter the range of the interactiveforces between them

– The steric stabilisation barrier doesn’t need to be so thick

BUT

• The surface area per gram of particles gets bigger and bigger,so the amount of dispersant required increases

Thus, on theoretical grounds, smaller particles require

larger amounts of dispersants

WHATWHAT’’S NEEDED TO STABILISES NEEDED TO STABILISE

NANOPARTICLES?NANOPARTICLES?


• When two particles with

absorbed polymeric or

oligomeric chains come

together, the chains are forced

to intermingle or to compress

• Generally this intermingling or

compression is energetically is a

LESS favourable state. The

particles are therefore kept

apart

• Polymeric dispersants used to

generate the steric stabilisation

layer

Localised high concentration of polymer

through compression or interpenetration gives

entropic repulsion and/or increased osmotic

pressure

STERIC STABILISATION OF PARTICLESSTERIC STABILISATION OF PARTICLES


DISPERSANT DESIGNDISPERSANT DESIGN

Single point anchorRandom

• Pigment dispersants contain anchoring and stabilising segments

Linear comb Branched / crosslinked

comb - brush

AB block

BAB block

• For solvent based dispersants anchor groups tend to be polar / ionic.

• The stabilising segments need to be soluble in the continuous medium


CRITERIA FOR THE STERIC STABILISINGCRITERIA FOR THE STERIC STABILISING

POLYMER CHAINSPOLYMER CHAINS

Solubility/Polymer Chain Chemistry

• The stabilisation chain must be soluble in the liquid phase.Must be a “better than theta” solvency system.

• End Use Compatibility – the chain must be compatible withresin/binder after solvent has evaporated. Otherwise film propertiessuch as haze, durability and adhesion may be degraded.

Polymer chain length

• The chain must be long enough to form a barrier of the requiredthickness

• Too long a chain tends to aid desorption

Ability to control composition and molecular weight of the steric chainsegment is critical in dispersant design


WHAT MAKES A GOOD DISPERSANT?WHAT MAKES A GOOD DISPERSANT?

• Segmented architecture vs random.

• Intuitively expect controlled architecture to be best with

anchoring and soluble portions of dispersant well segregated.

• Limited ability of random structures to provide effective steric

stabilisation.

Random vs segmented structures

Random AB block copolymer Linear comb polymer

Anchoring and

soluble segments all

mixed together.


MOL WT CONTROLMOL WT CONTROL

• Polymers have a distribution of molecular weights.

• Therefore even if the average mol wt of stabilisation chain is correct therewill be lot of material where the stabilisation chain is too small or too big

• The concept is the same for block or comb structures

Schematic illustration of block colplymers with broad mol

wt distribution

Schematic illustration of linear

comb with broad mol wt

distribution of steric chains


SOLVENT HYPERDISPERSANTSSOLVENT HYPERDISPERSANTS

INFLUENCE OF SOLVENT SOLUBILITYFIRST RECOMMENDATION NOT RECOMMENDED

(HIGHLY SOLUBLE)

RECOMMENDED (SOLUBLE) INSOLUBLE


Unsaturated Polyesters

And GelCoats

Thermosets/

Composites

Epoxies

Polyether -

Polyol Non-Phthalate

based

Phthalate

Based

Wire and Cable

And Compounds

Masterbatch and Compound

organic pigment inorganic and fillers

32000

D510SOLSPERSE

IRCOSPERSE

SOLPLUS

Acrylics

Polyester -

Polyol

Polyols

Liquid Colours

For Plastics

Thermoplastics

20000

R700

20000

K200

K500

3000

13650

K210

K500

30002153

2155

C825

C8002155

110003000

DP310

21000

DP310R700

D510

D540

D520

D530

D510

D520

Plasticiser

Dispersions

28000

ADDITIVES FOR THERMOPLASTICS AND THERMOSETSADDITIVES FOR THERMOPLASTICS AND THERMOSETS

D550


SOLVENT-FREE COATINGSSOLVENT-FREE COATINGS

OVERVIEW OF 100% ACTIVE SOLSPERSE PRODUCTSOVERVIEW OF 100% ACTIVE SOLSPERSE PRODUCTS

PRODUCT

PHYSICAL FORM

ANCHOR GROUP TYPE

SOLUBILISING

CHAIN POLARITY

20000

Liquid

Basic

High

32000

Solid (MPT 30 0C)

Basic

Medium

28000

Liquid

Basic

Medium - Low

8000

Liquid

Basic

Medium - Low

41000

Liquid

Anionic

High

36000

Solid (MPT 30 0C)

Anionic

Medium


DOSAGEDOSAGE

SOLSPERSE Hyperdispersants

X

X

20%

100

200

40%

PIGMENT

SURFACE

AREA

(m2/g)

% POLYMERIC SOLSPERSE REQUIRED BASED ON WEIGHT

OF PIGMENT IN MILLBASE (% AOWP)

2mg Polymeric SOLSPERSE / m2 Pigment Surface Area

This dosage can be more easily understood as % agent on weight of pigment (% AOWP)

To convert 2mg/m2 TO % AOWP use PIGMENT SURFACE AREA (BET)= % AOWP

Theoretical Amount

5


WHICH ANCHOR GROUP IS BEST?WHICH ANCHOR GROUP IS BEST?

ACID v AMINE

on TiO2


TYPICAL SURFACE TREATMENT ADDITIVESTYPICAL SURFACE TREATMENT ADDITIVES

PRESENT ON RUTILE TITANIUM DIOXIDEPRESENT ON RUTILE TITANIUM DIOXIDE

ORGANIC

TRIETHANOLAMINE

POLYDIMETHYLSILOXANE

TRIMETHYLOLPROPANE

SURFACTANTS

INORGANIC

ALUMINA

SILICA

ZIRCONIA


WHAT CONTRIBUTION DOES THE SURFACEWHAT CONTRIBUTION DOES THE SURFACE

TREATMENT MAKE TO THE PROPERTIES OF TiOTREATMENT MAKE TO THE PROPERTIES OF TiO22??

KEY PROPERTYSURFACE TREATMENT

Dispersability + compatibility

in the final application

ORGANIC

Improves pigment durabilityZIRCONIA

Promotes coating durabilitySILICA

Improves pigment wetting

in the dispersion

ALUMINA


DO PAINT PRODUCERS NEED POLYMERICDO PAINT PRODUCERS NEED POLYMERIC

DISPERSANTS TO DISPERSE TiODISPERSANTS TO DISPERSE TiO22??

Surface treatments do contribute significantly to the

dispersibility and stability of the titanium dioxide, but……………

In many cases this treatment is not enough to fulfill all

the coating requirements.

Coating properties can be enhanced further using polymeric

dispersants (gloss, haze, opacity and the ‘blueness’ of the white).

Pigment concentration in the dispersion can be increased, thus

increasing the potential for better hiding power and improved

productivity.


CAN THE TYPE OF POLYMERIC DISPERSANT CAN THE TYPE OF POLYMERIC DISPERSANT

AFFECT THE DISPERSION PROPERTIES OF TiOAFFECT THE DISPERSION PROPERTIES OF TiO22 ? ?

The anchor group on the polymeric dispersant can influence

the extent of dispersion stability and pigment loading with

tio2

This anchor group can be acidic, neutral or basic in nature

More effective dispersants will give better deflocculation

of the tio2 resulting in higher dispersion pigment concentration,

increased gloss and reduced haze.


POLYMERIC DISPERSANT CHOICE FORPOLYMERIC DISPERSANT CHOICE FOR

DISPERSING TiODISPERSING TiO22

SOLSPERSE 32600 - amine anchored, multiple chain,

multiple anchor type polymeric

dispersant (basic)

SOLSPERSE 36600 - acid anchored, multiple chain,

multiple anchor type polymeric

dispersant (acidic)


GRADES OF TiOGRADES OF TiO22 AND THEIR AND THEIR

SURFACE TREATMENTS SURFACE TREATMENTS

AcidicNoSilica / Alumina TIPURE R931

AcidicNoSilica / Alumina TIOXIDE RXL

Neutral / BasicYesSilica / Alumina TIOXIDE RTC30

BasicYesZirconia / Alumina TIOXIDE TR85

BasicYesZirconia / alumina TIOXIDE TR81

BasicYesAlumina TIPURE R700

BasicYesZirconia / Alumina TIOXIDE TR92

NATUREORGANICINORGANICGRADE


TiOTiO22 GRADE v PIGMENT CONCENTRATION : GRADE v PIGMENT CONCENTRATION :

AMINE AND ACID ANCHORED DISPERSANTSAMINE AND ACID ANCHORED DISPERSANTS

50

55

60

65

70

75

80

85

TR92 R700 TR81 TR85 RTC30 RXL R931

TiO2

Conc(%)

Dispersion System : MS Polyester

Solsperse Dosage : 2% AOWP

Dispersion Viscosity : Approx. 1 pas (1000 cps) @ low shear (37.6s-1)

32600

36600


TiOTiO22 GRADE v GLOSS : AMINE AND ACID GRADE v GLOSS : AMINE AND ACID

ANCHORED DISPERSANTSANCHORED DISPERSANTS

55

60

65

70

75

80

85

90

95

100

TR92 R700 TR81 TR85 RTC30 RXL R931

Gloss (600)

System : MS Polyester / Melamine

32600

36600


TiOTiO22 GRADE AND DISPERSANT CHOICE GRADE AND DISPERSANT CHOICE

Choice of optimum anchor group

can make a significant difference

- To rheology and

- Application performance


ROUTES TO NANO PARTICLESROUTES TO NANO PARTICLES

• Top Down - Milling

• Bottom Up- Particle formation/surface treatment


MILLING ROUTEMILLING ROUTE

• Conventional bead mills - Bead size (0.3mm +)

- Difficult to achieve <100nm

• Nano Mills - Bead size (0.05 – 0.1mm)

- Can achieve <100nm

• General rule : Particle size = Bead Size

achieved 1000


MAGENTA UV INK JET FORMULATIONMAGENTA UV INK JET FORMULATION

100.0

72.592.0Sartomer SR 306

15.0-Solsperse 35000

12.58Ink Jet Magenta E02 VP2621

%

MILLING ROUTEMILLING ROUTE


MILLING CONDITIONSMILLING CONDITIONS

• Bead mill with 0.3mm beads – 4 hours

- Particle size reduces from 185 ! 135nm

JN4824 Form 4Milling time vs Particle Size

100

120

140

160

180

200

0 50 100 150 200 250

Milling time (mins)

Pa

rtic

le s

ize

(n

m)

Particle size- initial (nm) Particle size- 1 day (nm)


MILLING CONDITIONSMILLING CONDITIONS

• Bead mill with 0.1mm beads – 50 mins

- Particle size reduces from 185 ! 82nm

Ink Jet Magenta E 02 VP 2621

With

Solsperse 35000

0

20

40

60

80

100

120

140

160

180

200

0 20 30 50

Milling Time

Part

icle

Siz

e (

nm

)

Particle Size - Diameter (nm)


MILLING CONDITIONS - SUMMARYMILLING CONDITIONS - SUMMARY

• Nano mills - Are critical for <100nm

- Particularly small beads

• As particle size reduces, surface area increases

• Dosage should be optimised for each specific PS produced


PARTICLE FORMATION PARTICLE FORMATION –– BOTTOM UP PROCESS BOTTOM UP PROCESS

- Flame Pyrolysis

- Sol Gel

- Organic Pigmentation Processes

- Variety of Other Routes


HOW CAN DISPERSANTS HELP?

• Dispersants may control the growth of particles, giving

smaller particles

• Dispersants may increase the solids loading achievable

before gelation. This should then give reduced shrinkage

on drying / firing, and better final product properties


SURFACE TREATMENTSURFACE TREATMENT

WITH ADDITIVESWITH ADDITIVES


SOLSPERSESOLSPERSE!! HYPERDISPERSANTS HYPERDISPERSANTS

Applications in Pigment/Particle Treatment

Solsperse hyperdispersants can be utilised in the manufacture of pigments

to provide a surface treatment which can improve the pigment

The anchor group of the hyperdispersant strongly adsorbs on to the pigment

surface, whilst the polymeric chain provides a high degree of steric stabilisation

Anchor GroupPolymeric Chain

Process Stage


QUALITY PRODUCTIVITY

SOLSPERSESOLSPERSE!! FOR PIGMENT / PARTICLE FOR PIGMENT / PARTICLE

Flow Throughput/Cycle Time

Strength Decreased mechanical wear

Dispersibility Increased solids (slurry, paste)

Product Stability Improved dry pigment for milling

Treatment - Benefits


SOLSPERSESOLSPERSE!! FOR PIGMENT FOR PIGMENT

Treatment - Quality

Quality

(strength or

brightness or

dispersibility,

etc)

Untreated

Pigment

Untreated

Pigment

+Solsperse! in

the formulationPigment

treated withSolsperse!

Solsperse!

treated pigment

+Solsperse! in

the formulation


SOLSPERSESOLSPERSE!! GRADES FOR GRADES FOR

Surface Treatment

• Choice by solvent / medium

• By particle surface

• Dosage by surface area


POSSIBLE PIGMENT TREATMENT OPTIONSPOSSIBLE PIGMENT TREATMENT OPTIONS

WITH SOLSPERSEWITH SOLSPERSE!! ADDITIVES ADDITIVES

STEPS TO CONSIDER WHEN INVESTIGATING USE OFSOLSPERSE! IN PIGMENT TREATMENT

• WHICH PIGMENT AND WHICH SYNTHETIC ROUTE?

• Organic or inorganic?

• WHICH APPLICATION IS THE PIGMENT DESIGNED FOR?

• Ink or paint?

• CHOOSE THE BEST SOLSPERSE! AGENT FOR PIGMENT SURFACE AND DESIRED

APPLICATION

•CONSIDER BEST APPROACH TO GETTING AGENT ONTO PIGMENT SURFACE, ie WHERE TO ADD SOLSPERSE!?

• Add during particle formation e.g. azo precipitation after coupling

• To an aqueous phase/as an emulsion prior to drying or milling (ensure homogeneous)


APPLICATIONS IN PIGMENT TREATMENTAPPLICATIONS IN PIGMENT TREATMENT

DOSAGE

Generally much less agent is utilised compared

with conventional solsperse applications

But for NANO:-

For inorganic pigments around 5-10% active SOLSPERSE!

agent should be used

For organic pigments around 20-40% active SOLSPERSE!

agent should be used

(THESE LEVELS ARE BASED ON NON DRYING PROCESSES)



Pigment Type

Potential Points of Addition (very dependent on pigment producer)

Benefits Seen (where known)

Mono Azo Reds

Rubines (Red 57.1)

• Add as an emulsion with rosin solution • Can be added after laking stage, but ... • Best results obtained if Solsperse/rosin

solution added to coupling stage

Inks: Better gloss, intensity Higher transparency Better strength development Reduced cycle times of production Improved dispersibility and reduced viscosity Improved performance in packaging gravure inks

Red Lake C (Red 53.1) Lithol Reds (Red 49.1) Permanent Red 2B (Red 48s)

• Best results seen when added as an emulsion

after coupling but prior to laking

Transparent, easy to disperse pigments for offset paste inks or gravure liquid inks

Diarylide Yellows

Yellow 12, Yellow 13

• Added as a solution (in acetic acid) during the

coupling stage • Can be used also as an alternative to post-

treatment with rosins or fatty amines • Can be added as an emulsion prior to drying

Stronger, brighter pigments Improved dispersibility in inks Improved dispersibility Control opacity/transparency



Benefits Seen

(where known)

• Added during or after milling processes • Or added during solvent crystallisation • Or added as an emulsion prior to drying

Improved rheology in solventborne paint and ink systems Increased colour strength

Pigment TypePotential Points of Addition(very dependent on pigment producer)

Phthalocyanine Blues Blue 15.4, 15.3


Pigment Type

Potential Points of Addition (Very dependent on pigment producer)

Benefits Seen (Where known)

Inorganics

Synthetic iron-oxides - Yellow 42 - Red 101

• Post treatments after high temperature processing

• Improved dispersibility in solvent paint system

• Higher strength pigment in solvent borne paint formulation


Titanium Dioxide

• Added as an emulsion prior to drying

•

• Increased solids loading in the slurry

• Improved performance in plastics final application

• Improved performance in solvent systems

Zinc Oxide

• Dependent on pigment manufacturer

• Improved application performance



Pigment Type

Potential Points of Addition (Very dependent on pigment producer)

Benefits Seen (Where known)

Iron blue or Milori blue - Blue 27

• Added to presscake prior to drying

• As above

• Improved dry pigments for publication gravure applications - improved dispersibility

• Decreased mechanical abrasion

Fillers (ATH, talc, kaolin, CaCO3 etc)

• Added to an aqueous slurry as emulsion prior to drying

• Improved application performance in plastics


SOLSPERSESOLSPERSE!! HYPERDISPERSANTS HYPERDISPERSANTS

APPLICATIONS IN PIGMENT TREATMENT

EMULSION/SOLUTION PREPARATIONSOLSPERSE! 3000 EMULSIONS

NON-IONIC EMULSION

1. MELT & MIX TOGETHER 20 PARTS SOLSPERSE! 3000 AND 5 PARTS SYNPERONIC A14 SYNPERONIC A14: C13-C15 MIXED ALCOHOL + 14 ETHYLENE OXIDE UNITS

2. WITH HIGH SHEAR STIRRING POUR MIXTURE INTO 75 PARTS OF WATER WHICH IS AT 50°C

ANIONIC EMULSION

1. MELT 25 PARTS SOLSPERSE! 3000 AND POUR INTO A SOLUTION OF 2.5 PARTS

TRIETHANOLAMINE/72.5 PARTS WATER WHICH IS AT 50°C AND BEING STIRRED RAPIDLY

USING A HIGH SHEAR MIXER THESE EMULSIONS ARE STABLE FOR SEVERAL MONTHS AT AMBIENT TEMP. & IN pH2-pH10

SOLSPERSE! 3000 SOLUTION

SOLSPERSE! 3000 12.5

BUTYL CELLOSOLVE 12.5

1N KOH SOLUTION 75.0

SLURRY THE SOLSPERSE! P850 IN THE KOH SOLUTION AND CLARIFY THE SLURRY BY THE ADDITION OF THE BUTYL CELLOSOLVE

FINAL SOLUTION IS SLIGHTLY HAZY AND AFTER STANDING 4 DAYS A SMALL AMOUNT OF PRECIPITATE

SETTLES WHICH IS READILY RE-DISPERSED ON STIRRING


TECHNICAL SERVICE / DEVELOPMENTTECHNICAL SERVICE / DEVELOPMENT

CAPABILITYCAPABILITY

• Bead Mills - Conventional Range (x3)

- Nano Mill Shortly

• Standard Additive recommendation based on enquiry

• Development capability for Polyester, Acrylics, PU,

Dispersants


DISPERSANT RECOMMENDATIONS FORDISPERSANT RECOMMENDATIONS FOR

NANOPARTICLE APPLICATIONSNANOPARTICLE APPLICATIONS

SOLSPERSE 36000

or

SOLSPERSE 39000

SOLSPERSE 3000

or

SOLSPERSE

11000/11200

[SOLSPERSE 27000/54000

if very hydrophobic]

Larger

Nanoparicles

SOLPLUS D520

or

SOLPLUS D510

SOLSPERSE 21000

or

SOLSPERSE 8000

SOLPLUS D540

or

SOLSPERSE 20000

Smaller

Nanoparticles

Medium polarity

Solvents

e.g. esters, ketones,

Aromatics, glycol,

esters, terpineol

Low polarity

solvents

e.g. aliphatics

Alcohol / water based

Sol-gel process

Note: A few products contain phosphorus, and this may cause

problems in some advanced electronic applications


PLEASE CONTACT US FOR YOUR

DISPERSANT NEEDS

QUESTIONS ?

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