Optisil is calcined kaolin and it is the best extender of titanium dioxide with excellent opacity and high whiteness that can improve efficiency and cut costs by partly replacing titanium dioxide. Optisil grades can be easily dispersed and has micronized-fine particle size, excellent anti-settling propert. Good stability against acid and alkali environments gives excellent corrosion stability.

Advantages of the use of Optisil

Improved levels of whiteness and hiding power of the paint.
Cost reduction in formula as titanium dioxide is partially replaced.
Increased stability of paint during storage. It acts as anti-settling and viscosity agent.
Gives exterior paints good weathering property and reduces specific gravity of the paint.
Improves optical properties of paint, increases opacity and ensures high whiteness.

Increase In whiteness

Whiteness power of a pigment is attributed to the power of dispersion of the pigment. When the concentration of this pigment increases, the distance travelled by the light that enters and leaves the film of the paint, is reduced given the fact that it is better reflected. In case of aluminium silicate (Optisil) usage, the small particle size and ease of use, ensures better dispersion and lets light enter to the paint structure and guarantees an increase in whiteness value of the paint.

Beginning formulation

Water based paint – Exterior use
Water 41.1%
Biocide 0.3%
Thickener 0.3%
Dispersant 0.2%
Antifoam 0.2%
TiO2 15.0%
Calcium carbonate 27.5%
Optisil PS 20 3.5%
Polymer emulsoion 11.5%
NaOH 10% 0.2%
Antifoam 0.2%

The hiding power of a paint depends mainly on the relation of reflected light reflected and absorbed light (naturally in function of the longtitude of the light wave). Any products that increase the reflection of light, make paint film more opaque or increases its hiding power.

Coatings and Paint Applications

Optisil coatings and paint grades are designed for coating industry with the purpose of filling, saving costs, giving color and improving performance.

Optisil P 50, PS 20 and PS 80 have high brightness and opacity. All can be applied in water and oil based applications freely. With high brightness, narrow particle size distribution, high dispersibility, high hiding power, high opacity and tinctorial property. In the production of Optisil P 50, 1250 mesh is used. For Optisil PS 20 and PS 80, 4000 mesh is used to define narrow particle size. Consumers can save costs by adding these unique grades into their formulations and Optisil grades can replace about 10-20% TiO .

Chemical Specifacation (%)

SiO2 Al2O3 Fe2O3 TiO2 CaO Na2 K2O MgO
52 ± 2 45 ± 2 ≤ 0.5 ≤ 0.8 < 0.5 < 0.3 < 0.1 < 0.2

Applications

Architectural and decorative coatings, walls, floors and ceilings ,wood substrates, e.g. furniture, doors and window frames, metallic substrates, e.g. radiators, fences and tanks, industrial coatings ,inks, offset inks, gravure inks, automotive coatings, flexographic inks, screen inks, news ink

Key benefits

  • High whiteness
  • High brightness
  • Resistance to abrasion
  • Opacity
  • High hiding power
  • Flattening property
  • Ease of usage
  • High dispersibility
  • High mechanical strength
  • Cost effective
  • Extender
  • Filler
  • Rheology controller

Typical properties

Items Optisil P 50 Optisil PS 20 Optisil PS 80
Brightness (R457, min, %) 91 93 93
Particle size (≤2μ, %) 50±5 80±2 80±2
Residue on 325 mesh (%) ≤ 0.05 ≤ 0.003 ≤ 0.005
Moisture (%) ≤ 0.5 ≤ 0.5 ≤ 0.5
Oil absorption (g/100g) 55±5 60±5 60±3
pH 6.0-8.0 6.0-8.0 6.0-8.0
Density (g/cm?) 2.7 2.7 2.7

Packaging

25 kgs multi layer paper/PE bag, 1000 kgs big bag.

Storage

Store in cool, dry and well ventilated areas. For more details, please refer to the material safety data sheet.

Paper Industry Applications

Optisil PP 90 and Optisil PP 90R are used in the filling and coating of paper. In filling, these unique products are mixed with the cellulose fiber and form an integral part of the paper sheet to give it body, color, opacity and printability. Also, they ensure high mechanical strength and resistance to abrasion. In coating of paper,

Optisil is plated along with an adhesive on the paper’s surface to give high gloss, color, high opacity and greater printability. All improve the paper whiteness, smoothness, ink absorbancy, print fitness and glossiness. Optisil paper industry grades are designed to help paper manufacturers about the biggest problems they have to solve, saving costs and improving performance.

Optisil grades help paper manufacturers save costs by extending high value ingredients or replacing them, e.g. TiO . Paper manufacturers generally use calcined kaolin about 20-30%.

Chemical components ratio (%)

SiO2 Al2O3 Fe2O3 TiO2 CaO Na2O K2O MgO
55 ± 2 45 ± 2  0.5 0.8 0.5 0.2  0.1 0.2

Applications

Printing and writing paper, wood free paper, wood containing paper, newsprint paper, packaging and board paper, kraft paper, recycled board, liner board, specialty paper, thermal paper, carbon paper, inkjet paper

Key benefits

  • High whiteness
  • High brightness
  • Low abrasion value
  • Opacity
  • Smoothness
  • Printability
  • Ink absorbency
  • Coating coverage
  • Can replace TiO fully 2
  • Cost effective

Typical properties

Items Optisil P 50 Optisil PS 20
Brightness (R457, min, %) 93 93
Particle size (≤2μ, %) 88±2 88±2
Residue on 325 mesh (%) ≤ 0.003 ≤ 0.003
Moisture (%) ≤ 0.5 ≤ 0.5
Oil absorption (g/100g) 65±5 70±5
Dispersibility (μm) ≤ 45 ≤ 45
Abrasion value (mg/100.000 times) ≤ 33 ≤ 33
pH 6.0-8.0 6.0-8.0
Density (g/cm?) 2.7 2.7

Packaging

25 kgs multi layer paper/PE bag, 1000 kgs big bag.

Storage

Store in cool, dry and well ventilated areas. For more details, please refer to the material safety data sheet.