Ready Reckoner Refractive indices

Excerpt: In this article the refractive index is at a glance. It plays a very important role with respect to opacity / covering of paint. Underlined materials are related to paint industry.

Refractive indices


Mukund Hulyalkar


In this issue we have given the refractive indices at a glance. It plays a very important role with respect to opacity / covering of paint. Underlined materials are related to paint industry.

Major Indices TiO2 (R) 2.760 is highest, TiO2 (A) 2.550, ZnO 2.010 Water 1.333, Air 1.000, MTO / Toluene 1.550

Opacity of the paint = RI of Pigment - RI of Binder / Resin

| Refractive indices of Meterial | value |
| --- | --- |
| Refractive Index of an extender is very less i.e. | 1.600 |
| whereas refractive index of a resin is also 1.600, which is as good as that of extender. | -1.600 |
| Result:- Transperant | 0 |

| Refractive indices of Meterial | value |
| --- | --- |
| Refractive Index of TiO2 (R) is highest i.e. | 2.760 |
| whereas refractive index of a resin is | -1.600 |
| Result:- Highest Opacity | 1.160 |

| Refractive indices of Meterial | value |
| --- | --- |
| Refractive Index of TiO2 (R) is highest i.e. | 2.760 |
| whereas refractive index of Water is | -1.330 |
| Result:- Highest Opacity | 1.430 |

| Refractive indices of Meterial | value |
| --- | --- |
| Refractive Index of TiO2 (R) is highest i.e. | 2.760 |
| whereas refractive index of MTO | -1.500 |
| Result:- Lowest Opacity | 1.260 |

| Liquids | RI Value |
| --- | --- |
| Water H2O | 1.333 |
| Paraldehyde | 1.405 |
| Methyl Acetate | 1.450 |
| Carbon Tetrachloride | 1.460 |
| Glycerol | 1.470 |
| Liquid Parrafin | 1.480 |
| Toluene | 1.497 |
| Benzene | 1.501 |
| Ethyl Salicylate | 1.523 |
| Chlorobenzene | 1.525 |
| Methyl Salicylate | 1.538 |
| Ethyl Cinnamate | 1.559 |
| Benzyl Benzoate | 1.568 |
| Aniline | 1.586 |
| Quinoline | 1.627 |
| α- Monobromonaphthalene | 1.660 |
| Mercury Potassium Iodide | 1.717 |
| Methylene Iodide | 1.737 |
| Methylene Iodide & Sulphur (Saturated) | 1.780 |
| Barium Mercury Iodide aq | 1.793 |
| Potassium Iodide & Mercuric Iodide | 1.820 |
| Solution 35% by weight CH2I2 | 1.868 |
| Solution 31% by weight SnI4 | 1.868 |
| Solution 16% by weight AsI3 | 1.868 |
| Solution 8% by weight SbI2 | 1.868 |
| Solution 10% by weight S | 1.868 |
| Hydrogen Disulphide | 1.885 |
| Phosphorus in Carbon Disulphide | 1.950 |
| Yellow Phosphorus 8 parts by weight | 2.060 |
| Yellow Sulphur 1 part by weight | 2.060 |
| Methylene Iodide 1 part by weight | 2.060 |
| Mercuric Iodide in Aniline or Quinoline | 2.200 |
| Oil Paraffin | 1.440 |
| Oil Olive | 1.460 |
| Oil Turpentine | 1.470 |
| Oil Cedar | 1.516 |
| Oil Cloves | 1.532 |
| Oil Cinnamon | 1.601 |
| Polysterene 15°C | 1.592 |
| Polysterene 35°C | 1.589 |
| Polysterene 55°C | 1.586 |
| Polycyclohexyl Methacrylate 15°C | 1.507 |
| Polycyclohexyl Methacrylate 35°C | 1.504 |
| Polycyclohexyl Methacrylate 55°C | 1.501 |
| Polymethyl Methacrylate 20°C | 1.491 |
| Ice | 1.310 |
| Sodium Fluoride | 1.325 |
| Lithium Fluoride | 1.392 |
| Strontium Fluoride | 1.430 |
| Calcium Fluoride (Fluorite) | 1.433 |
| Sodium Aluminum Sulphate (Soda-alum) | 1.439 |
| Pottassium Aluminum Sulphate (Potashalum) | 1.456 |
| Fused Silica | 1.458 |
| Ammonium Aluminum Sulphate (Ammonia-alum) | 1.459 |
| Barium Fluoride | 1.470 |
| Pottassium Chloride | 1.490 |
| Sodium Chloride (Natural) | 1.544 |
| Sodium Chloride (Synthetic) | 1.549 |
| Cadmium Fluoride | 1.550 |
| Potassium Bromide | 1.560 |
| Topaz | 1.630 |
| Potassium Iodide | 1.667 |
| Caesium Bromide | 1.697 |
| Magnesium Aluminum MgO.Al2O3 | 1.715 |
| Magnesium Aluminum MgO.3Al2O3 | 1.726 |
| Magnesium Aluminum MgO.5Al2O3 | 1.729 |
| Grossularite (Garnet) | 1.735 |
| Magnesium Oxide (Periclase) | 1.737 |
| Lead Fluoride | 1.760 |
| Silver Chloride | 2.060 |
| Zinc Sulphide (Blend / Sphalente) | 2.370 |
| Diamond | 2.419 |
| Thallium Bromide - Iodide | 2.629 |
| Potassium Dihydrogen Phosphate | 1.510 |
| Ammonium Dihydrogen Phosphate | 1.524 |
| Crystaline Quartz | 1.544 |
| Sodium Nitrate | 1.587 |
| Calcspar | 1.658 |
| Aluminum Oxide (Corundum) | 1.768 |
| Titanium Dioxide | 2.600 |
| Titanium Calcium White(25%+75%) TiO2- CaSO4 | 1.800 |
| Titanium Dioxide CaSO4 | 1.980 |
| Titanium Barium White(25%+75%) TiO2- BaSO4 | 1.800 |
| White Lead PbSO4.PbO | 1.930 |
| Lithopone ZnS. BaSO4 | 1.840 |
| Zinc White ZnO | 2.020 |
| White Lead (Carbonate) | 1.940 |
| Antimony Oxide Sb2O3 | 2.180 |
| Zirconium Oxide ZrO2 | 2.500 |
| Titanium Dioxide (Anatase) TiO2 | 2.500 |
| Titanium Dioxide (Rutile) TiO2 | 2.600 - 2.900 |

| Transparent White Pigments | RI Value |
| --- | --- |
| Diatomaceous Earth SiO2 | 1.435 |
| Aluminum Stearate | 1.490 |
| Aluminum Hydrate Al(OH)3 | 1.500 |
| Gypsum CaSO4 | 1.520 |
| Silica SiO2 | 1.553 |
| China Clay | 1.558 |
| Talc | 1.539 |
| Mica | 1.563 |
| Anhydrite CaSO4 | 1.570 |
| Chalk CaCO3 | 1.513 |
| Barytes BaSO4 | 1.630 |
| Barium Carbonate | 1.530 |

| Iron Oxide Pigments | RI Value |
| --- | --- |
| Ochre Yellow | 2.050 |
| Sienna Raw | 1.870 |
| Sienna Burnt | 1.850 |
| Umber Raw | 1.870 |
| Umber Burnt | 2.200 |
| Iron Oxide | 2.780 |

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