Tintometer, Lovibond Color, measurement

Lovibond tintometer—device for measuring the color of a petroleum product, particularly petrolatums. The melted petrolatum is contained in a cell and the color is compared with a series of yellow and red Lovibond glasses. The length of the cell and the color standards that give the best match are reported. See color scale. 

The color of the wax will affect the color of the finished product. A Lovibond Tintometer is often used for color measurements, whereby the color of the raw material is compared against a series of colored standard glasses, under a standard light source. The color of the solidified wax of the same sample may be different depending on the amount of occluded air, the rate of cooling, or surface finish. Therefore, the color of many waxes is best measured in the molten state. Two ASTM color standards are used to measure dark-brown to off-white color and off-white to pure white. The refractive index and the specific gravity are other parameters often determined. 

Lovibond [Tintometer]. TM for color measurement and water testing equipment used in standard methods specified by ASTM, AOCS, APHA, European and and U.S. Pharmacopoeia, ISO, BA, and IP. 

Lovibond tintometer color can also be measured using objective automated instruments. In one version, the intensities of three light beams (red, yellow and white) transmitted by the oil are measured by photoelectric cells, and the results displayed as red and yellow color readings. The white light beam acts as a reference beam, and allows compensation for variation in the intensity of the light source (Rossell, 1986). AOCS Official Method Cc 13j 97 (Firestone, 1998) specifies how an automated tintometer should be used. However, this standard is valid only for refined oils. 

The color of coconut is measured in a Lovibond Tintometer, using a 1-inch or 51 -inch cell for dark and hght colored oils, respectively. Results are given in red and yellow units describing the combination that matches the sample color. Alternatively, the optical density of the oil can be measured with the use of a spectrophotometer in a suitable cell at a wavelength of maximum absorbance. 

The bleaching process is used to remove color bodies and other minor impurities. The bleaching adsorbent, usually a clay product, removes residual soap from alkali refining, aldehydes and ketones from decomposed peroxides, and color bodies. The color of bleached oil is widely measured by the Lovibond tintometer color scale. 

The Lovibond tintometer (IP 17) is used to measures the tint and depth of color by comparison with a series of red, yellow, and blue standard glasses. Waxes and petrolatum are tested in the molten state, and a wide range of cell sizes is available for the different types. 

The color of the oil becomes darker during frying. The change in color can be measured with a Lovibond tintometer. For a qnick assessment of color, comparison kits are available. As in the case of FFA, color alone does not express the quality of the used oil. 

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