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Extender - An amazing value still comes at Lower Cost....even TodayTRANSCRIPT
EXTENDER : AMAZING VALUE STILL COMES AT LOW
COST…EVEN TODAY!
Kaushal.KansaraVIMAL MICRONS LIMITED
CONTENTS Indian Paint Industry – Current Scenario Introduction of Vimal Microns Limited Importance of Extender in Paint Industry Introduction of 2 Micron Calcium Carbonate –
CARB 201 Introduction of 2 Micron Talc – TALC 2 M Introduction of CARB 10 B to Small Scale Paints
Manufacturers
INDIAN PAINT INDUSTRY CURRENT SCENARIO Total Market is more than Rs.15,000 Crore Decorative segment has an edge compare to
Industrial Segment in ratio of – 70:30 Few Corporate Giants have share of almost 55 %
of the entire market Small Scale Paints Manufacturers are catering
around 45% of the market demand
INDIAN PAINT INDUSTRY – POSITIVE SIDE Per capita consumption of Paints in India is 1.25
kgs. Compare to other develop countries it is too low Growth of Small Scale Paints Manufacturer – more
than 20% during last couple of years. Market Prediction – Should double by 2013.
INTRODUCTION TO VIMAL MICRONS LIMITED Founded in 1995-96, under direction of
Mr.G.K.Patel. Flagship company of VIMAL GROUP OF
INDUSTRIES – Having turnover of more than 1700 Crore INR.
Producing around 1,20,000 MT per Annum. Having Two state of the art units located at
Mehsana & Alwar. Specialize in Micronizing of Minerals such as
CALCITE, TALC, DOLOMITE, BARYTE, CHINA CLAY, SILICA, WHITE WHITING & MICA.
SMALL VIDEO TOUR TO VIMAL MICRONS LIMITED
EXTENDER : SOMETHING CHEAP TO TAKE UP SPACE ? NOT SO..!
SECONDARY PIGMENT :Which can be used to improve certain properties in Paints.
Extender
EFFECTS OF ADDITION OF EXTENDER TO PAINTS DEPENDS ON
Mineralogy (crystal structure, Mohs hardness, etc.) Oil absorption, brightness, pH, refractive index, etc. Chemical Properties Particle size and particle size distribution Particle shape and aspect ratio
PRINCIPAL EXTENDERS TYPES & TYPICAL PROPERTIES
Extender (Common
Name)
Chemical Nomenclatu
reSpecific Gravity
Particle Size
Oil Absorption Ph Refractive
Index Hardness Particle Shape Utility
CalciteCalcium Carbonate 2.7 1.5 - 30 6 - 30 9 – 10 1.65 3 Various
Fill, Corrosion Control
TalcMagnesium Silicate 2.8 2.5 - 40 30 - 50 8 – 9 1.58 1 Various
Fill, stress mitigation, Film reinforcement
Silica (Amorphous) Silica 2.6 5 - 40 20 - 50 6 -7 1.54 7 Nodular
Fill, inertness, flatting, abrasion resistance
Silica (Fumed) Silica 2.2 0.01 - 0.11 150 - 300 6 -7 1.54 7 Nodular
Fill, flatting agent, rheology
China Clay, Kaolin
Aluminum Silicate 2.6 0.5 - 3.5 25 - 50 4.5 – 7 1.57 2.5 Platy Fill, opacity
Mica
Aluminum Potassium Silicate 2.8 5 - 20 50 -70 7.5 - 9.5 1.59 2 .83 Platy
Fill, barrier properties, corrosion resistance
BaryteBarium Sulphate 4.5 2 - 30 10 7 1.64 3 Nodular Fill, inertness
Dolomite
Calcium Magnesium Carbonate 2.8 1.5 - 30 6 – 30 9 – 10 1.65 3.5 Various Fill,
MOHS HARDNESS Mohs hardness is a relative measure of abrasion
resistance of a mineral. Talc is the softest mineral and diamond is the
hardest. Harder minerals will have better scrub resistance
and better burnish resistance.
MOHS HARDNESS SCALE
0
2
4
6
8
10
12
Talc China Clay, Kaolin Mica Calcium Carbonate Baryte Dolomite Silica (Amorphous) Silica (Fumed)
Diamond
OIL ABSORPTION The oil absorption of a mineral is a
characteristic of the mineral itself and depends how finely it is ground. The denser the mineral, the lower the oil absorption. The oil absorption indicates the amount of the resin the mineral will absorb and affects the viscosity of the paint and the gloss.
DRY BRIGHTNESS The dry brightness and color of a mineral
in oil will affect how the mineral appears in a coating. A mineral can have excellent dry brightness but change color when put into a resin. Color in oil can vary from cream to gray or even green, depending on the mineral. The color is usually an effect of minor impurities.
PH pH is a function of the metallic ions
in the structure. Aluminum in the structure makes the mineral acidic. Calcium, potassium, barium or sodium make the mineral alkaline. Some minerals, such as calcite or serpentine, are soluble in acids and can’t be used in coatings that have pH <7.
AESTHETICS —THE EFFECT OF EXTENDERS ON OPACITY Extenders do not enhance the true opacity or
color of the coating film. The refractive index is a measure of how light is bent when it passes from one medium to another. The higher the refractive index, the more the light is bent which results in greater opacity. Rutile TiO2 has a high refractive index and gives good opacity to paints. All extenders have refractive indexes that fall in a range between 1.45 and 1.65, they have a significantly lower refractive index than TiO2 and don’t contribute to the opacity, but they can be used in conjunction with TiO2 to achieve opacity at reduced cost.
CHEMICAL EFFECT While the physical aspects of extenders are of
particular importance to their use in Paints, so is their chemical make up. Whiting may be of value as a pigment for anti-corrosive paints, Larger particle sized pigments, which are favored for metal primers, give coarser films with better flow and tooth for improved intercoat adhesion. Fine, wet ground and precipitated Carbonates are used in gloss finishes and enamels, while intermediate sized pigments are favored for semi-gloss pigments and flats. Whiting of intermediate fineness is also used in exterior house paints, where the pigments improve mildew resistance, reduce chalking as well as assist in controlling cost. Larger sized grades of whiting are said to give good color retention in exterior house paints.
CHEMICAL EFFECT Mica has also been used as an extender. As mica is
more chemical resistant than aluminum, this extender is particularly valuable where the paints is exposed to conditions of extreme pH.
China Clay may be used more effectively in inhibitive systems. China clay that are platy like the Talc, will also tend to reinforce the film, and are said to improve the sanding of industrial primers.
CHEMICAL EFFECT Baryte is a small inert nodular pigment that packs
well and gives excellent enamel holdout properties. Baryte is available in two forms, naturally ground Baryte and the less common but whiter precipitated grade, which is usually finer and higher in oil absorption than the natural product. Baryte is the heaviest extender with the lowest oil absorption characteristics. It is widely used in low VOC systems, but needs some additional support in order to control settling.
PARTICLE SIZE AND PARTICLE SIZE DISTRIBUTION The particle size of a mineral can be expressed in
several ways, depending on the method by which it is measured.
Common methods of measuring particle size are Hegman fineness, screening, sedimentation and laser light scattering method.
Laser Light Scattering method is the latest and most advance method.
Each method will yield a distinct result. When comparing data of different minerals, be sure
that the particle size distributions are measured the same way.
HEGMAN FINENESS Hegman fineness measurements indicate only size
of the coarsest particles. This is a good first approximation of the fineness of grind and the dispersion of the mineral pigments in the paint.
Hegman fineness does not tell anything about the overall distribution of the particle of the mineral.
SCREENING Screen residue only indicates the % coarser than
some given mesh size. Typical mesh sizes are 100, 200, 325, 450 and 500 mesh. These are equal to 150 μm, 75 μm, 44 μm, 32 μm and 30 μm respectively.
Screenings can be done dry or wet. Wet screenings usually yield a smaller quantity retained than dry screenings.
SCREENING The screen residue measures the quantity of
particles retained, it does not tell anything about the size of those retained particles except that they are larger than the screen openings.
The screen residue does not tell anything about the sizes of the particles that pass through the screen except that they are smaller than the screen openings.
500 Mesh (30 µm)
SEDIMENTATION
Sedimentation methods measure particle size by Stokes Law and yield results expressed as equivalent spherical diameter.
The median equivalent spherical diameter of the mineral is often given. The median is the size where 50 % of the particles are larger and 50 % are smaller.
LASER LIGHT SCATTERING METHOD Laser diffraction measurement methods give a different
particle size and particle size distribution than sedimentation methods.
Particle size is usually expressed as D10, D50 and D99. (the percent finer than the stated micron size)
Laser diffraction methods usually give a coarser particle size than sedimentation methods.
PARTICLE SIZE DISTRIBUTION GRAPH
Particle Size Distribution
0.1 1 10 100 1000
Particle Size (µm)
0
20
40
60
80
100
Vol
ume
(%)
No Name Supplied, Saturday, December 18, 2010 1:59:43 AM
IMPORTANCE OF PARTICLE SHAPE Differences in shape and size of different
extenders can lead to many practical benefits. The make up of the extender package was largely predicated on cost reduction. Since then, if only slowly, we have come to understand that care in apportioning the available extender volume between the various extenders available to the formulator can result in films with enhanced mechanical and even performance characteristics. Different paint types having different usage and performance requirements benefit from different types of extenders.
PARTICLE SHAPE – NODULAR EXTENDERS Some of the most effective fillers in terms of
low oil absorption are the nodular extenders such as , Calcium Carbonate, baryte and amorphous silica (as opposed to the fumed and diatomaceous types). These materials provide little value in aesthetics, however, as do the finer Calcium Carbonate, which are used effectively in combination with TiO2 to enhance opacity. This is achieved by optimization of the manner in which the film scatters light, and is discussed below. That being said, nodular pigments contribute little to the mechanical properties of the film.
PARTICLE SHAPE – PLATY EXTENDERS Flat, platy extenders such as Mica and some Talc and
clays are also highly absorbent, again because of their very high surface area per unit weight compared to nodular extenders such as Silica, Baryte or Calcium Carbonate. These extenders tend to enhance the mechanical properties of the film by lateral reinforcement. It has also been reported that platy extenders of this type not only reinforce the film but minimize the accretion of internal stress by allowing better dissipation of stress along the plane of the pigment. Flat, platy pigmentation orientated parallel to the substrate also tends to decrease the porosity of the applied film, sealing it and reducing the tendency of high PVC primer films to bubble when recoated.
ASPECT RATIO Mineral particles come in any of several basic shapes : .
Sphere Cube Needle
Block Plate / Flake Fiber
ASPECT RATIO Needle/Fiber Aspect
Ratio : Ratio of mean length to mean diameter
Plate Aspect Ratio : Ratio of mean diameter of a circle of the same area as the face of the plate to the mean thickness of the plate
L
D
TD
ASPECT RATIO Aspect ratio is a description of the overall shape
of the particle. It describes the length to diameter ratio, the face to thickness ratio, etc.
Cubes or spheres have 1:1 aspect ratio Blocks have 2:1 to 4:1 aspect ratio (length:width) Needles or fibers have 5:1 to 200:1 aspect ratio
(length:width) Plates or flakes have 20:1 to 200:1 aspect ratio
(face:edge)
TALC Talc is a platy magnesium silicate mineral.
Its properties include high oil absorption, softness and high brightness .
We are having an excellent quality deposits of Talc situated at Himachal Pradesh and in Rajasthan.
The use of talc in coatings contributes to gloss control,TiO2 spacing, anti-settle, sandability of primers, inter-coat adhesion and corrosion/blistering resistance.
NEW DEVELOPMENT – TALC 2 MPARTICLE SIZE ANALYSIS VIMCRO TALC 2 M
PHYSICAL ANALYSISResidue 400 # NilResidue 500 # 1.0% MaxDry Brightness Min. 97.0% Bulk Density [untapped] 300 – 400 Gm/LitOil Absorption 40.0 – 45.0 Gm/100 GmWater Demand 45.0 – 50.0 ml/100GmSpecific Gravity 2.7pH of Sat. Solution 9.0 – 10.0Moisture Content Max. 0.5%CHEMICAL ANALYSIS% of MgO 29.81%% of SiO2 60.32%% of AI2O3 0.67%% of CaO 1.69%% of Fe2O3 0.47%Loss On Iginition 6.61%
CALCIUM CARBONATE Natural calcium carbonate (GCC) is one of the
most abundant filler minerals. It forms in several crystal shapes. Shapes include
blocky (chalk), scalenohedral (calcite), short needle acicular (aragonite).
Calcium carbonate has high brightness, low oil absorption, can be ground to ultra fineness, and is relatively inexpensive.
It is widely used in all kinds of paints and coatings, especially in interior and exterior paints.
Calcium carbonate is unstable in acidic conditions and soft (poor abrasion resistance).
NEW DEVELOPMENT – CARB 201PARTICLE SIZE ANALYSIS VIMCRO CARB 201
PHYSICAL ANALYSIS
Residue 400 # Nil
Residue 500 # 0.05% Max
Dry Brightness Min. 94.0%
Oil Absorption 20.0 – 25.0 Gm/100 Gm
Water Demand 22.0 – 30.0 ml/100Gm
Bulk Density [untapped] 650 – 750 Gm/Lit
pH of Sat. Solution 9.0 – 10.0
Specific Gravity 2.7
CHEMICAL ANALYSIS
% of CaCO3 95.0± 1.0%
% of MgCo3 3.0 ± 1.0%
% of Acid Insoluble 1.5 ± 0.5%
% Loss On Iginition 43.0 ±1.0%
NEW DEVELOPMENT – CARB 10 BPARTICLE SIZE ANALYSIS VIMCRO CARB 10 B
PHYSICAL ANALYSIS
Residue 400 # Nil
Residue 500 # Nil
Dry Brightness Min. 95.0%
Oil Absorption 23.0 – 27.0 Gm/100 Gm
Water Demand 24.0 – 32.0 ml/100Gm
Bulk Density [untapped] 650 – 650 Gm/Lit
pH of Sat. Solution 9.0 – 10.0
Specific Gravity 2.7
CHEMICAL ANALYSIS
% of CaCO3 95.0± 1.0%
% of MgCo3 3.0 ± 1.0%
% of Acid Insoluble 1.5 ± 0.5%
% Loss On Iginition 43.0 ±1.0%
BARYTE
Natural barium sulfate, known as baryte, is a high brightness, high specific gravity, low oil absorption extender.
The specialty of Baryte is High Refrective Index.
Baryte is also known for its excellent compatibility with Coloured Pigments.
It finds use in powder coatings because of its high specific gravity, good brightness and low oil absorption.
CHINA CLAY
Hydrated Aluminum Silicate – Popularly known as Kaolin is widely used by Paints, Paper, Ceramic & Rubber Industries.
Because of its Lamellar form, it gives good coverage.
China Clay is chemically inert mineral. It has Higher thicksotropic nature as well as
good water absorption capacity. The modified version – Calcined China Clay
improves Opacity.
DOLOMITE Dolomite is a natural form of Calcium
Magnesium Carbonate with high degree of Whiteness.
It is also noted for its remarkable wettability and dispersibility as well as its moderate Oil Absorption.
It gives good Whiteness to the Paints, because of its Higher Bulk Density, Less Reactive.
MICA Mica is a platy mineral. There are several
different forms of mica : Muscovite, Phlogopite, Biotite, etc.
Fine dry ground mica is used in joint cement and texture paints for mud crack resistance.
Fine wet ground mica is used in exterior latex paints for tint retention and weatherability.
Mica is used as the base for special effect pigments.
SILICA Natural silica is the most abundant mineral
family on Earth. Common varieties include quartz, sandstone, silica sand, tripoli, opal and novaculite (microcrystalline quartz).
It has low oil absorption, good brightness, high purity, and excellent abrasion resistance.
ROLE OF EXTENDER IN PAINTSAesthetic Properties : Gloss Control Sheen Opacity Brightness Dirt Pick-up and Cleanability Textures & Smoothness
ROLE OF EXTENDER IN PAINTSMechanical & Physical Properties : Hardness Impact Resistance Resistance to applied stress Film reinforcement Porosity Cracking and Checking resistance
ROLE OF EXTENDER IN PAINTSWet Paint & Proccessing Properties : Viscosity Flow and Leveling Ease of Dispersion Sedimentation and Settling
ROLE OF EXTENDER IN PAINTSPerformance and Resistance Properties : Abrasion and Scrub Resistance Permeability Corrosion Resistance Chemical Resistance Thermal Properties (Insulation & Conductivity) Electrical Properties(Insulation &Conductivity)
ROLE OF EXTENDER IN PAINTSOther : Cost Control Filler – Spacer