Paint Testing

Paint Testing

Barathlab is involved in testing the quality of paint as well as its adhesive properties to give suppliers the confidence to move ahead with the most economical option to suit the application with high accuracy and reliability. The application industry varies from automotive to earth movers as cost reduction and corrosion resistance is the order of the day. The list of paint properties include.

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Viscosity Measurement

Barathlab uses the Ford viscosity cup which is a simple gravity device that permits the timed flow of a known volume of liquid through an orifice located at the bottom. Depending on the kinematic viscosity, the rate of flow becomes directly proportional. It should be noted that the true viscosity during applications are sensitive to temperature so the testing done must maintain the right temperature for the liquid as well as the cup.

Gloss and Finish

Customers prefer different finish to their products with varying level of shine and glossiness to the finish, which is a characteristic of the reflective property of the paint.

  • The gloss level can vary from a dull to a full shiny look, and though the terms aren’t standardized, the common terminology is:
  • Gloss – A highly shiny glossy finish which is very reflective
  • Satin – (Also referred to as lustre, Semi Gloss or Pearl) – A soft sheen paper which is half way between Gloss and Matt.
  • Matt – A totally flat finish with no sheen or reflective properties

Gloss can be used as a measure of the quality of the surface since the curing is affected that ultimately leads to poor adhesion for the coated surface. A glossmeter is used to measure the light that is incident on the surface at a particular angle. The intensity is then recorded based off the reflectivity and absorption of the surface.

The procedure is as per IS-101 Part 3 & 4 – Sec 4

Fineness of Grind

The material that makes up the paint is ground into fine particles for easy dispersion to the liquid medium. This physical property is termed as “grinds” which measures both the size of the particle as well as the amount of dispersion. We currently use Grind gages to help a variety of industries not limited to paint, plastic, pigment, coatings, paper, ceramic, food etc.

The procedure is as per IS-101 Part 3- Sec 5

Adhesion

The adhesion test measures the adhesion of organic coatings to smooth surfaces. The test material is applied at a uniform thickness and on drying, a rounded stylus that is loaded with increasing amount of weight is used to determine the value at which the coating is removed from the substrate

Flash point

The flash point is the lowest temperature at which the vapors from a volatile material will ignite on application of a source. The sample is contained in an open cup which is heated and, at intervals, a flame brought over the surface. The measured flash point will actually vary with the height of the flame above the liquid surface and, at sufficient height, the measured flash point temperature will coincide with the fire point. This property can provide suppliers with a measure of the safety hazard.

The procedure is as per IS-101 Part 1- Sec 6

Volume Solid

A volume Solid is a measure of the volume of solid film-forming ingredients in a can of paint, or the material that remains when the paint has dried. This denotes the true volume of the paint and is an indicator of the quality of the paint used and cost comparison.

The procedure is as per IS-101 Part 8 -Sec 6

Dry Film Thickness

DFT is the thickness of a coating as measured on top of a substrate. This can either be a single layer or multiple layers. The coating thickness is measured only after the paint has dried and should follow recommended coating parameters. This property plays a part in the corrosion prevention of the substrate and influences the durability of the coat.

The procedure is as per IS-101 Part 3 – Sec 2

Wet Film thickness

WFT is the thickness of wet paint that is liquid based, which is maximum after application of the coat and before the volatile materials are lost. This property needs to be determined so that the right amount of paint is used to avoid the substrate coming in direct contact with the corrosive environment. Barathlab ensures that the right timing is followed for the measurement as this is sensitive right after the point of application of the paint, thus preventing film contamination.

S.No Specific Test Performed Test method specification against which tests are performed
1 Consistency IS-101 –Part 1-Sec 5
2 Viscosity –ford Cup – 4 IS-101 –Part 1-Sec 5
3 Mass in Kg/10 Litres IS-101 –Part 1- Sec 7
4 Drying time IS-101 –Part3- Sec1
5 Finish IS-101 –Part3- Sec 4
6 Gloss IS-101 –Part4- Sec 4
7 Fineness of Grind IS-101 –Part3- Sec 5
8 Colour IS-101 –Part4- Sec 2
9 Water Content IS-101 –Part2- Sec 1
10 Scratch Hardness IS-101 –Part5- Sec1
11 Flexibility and Adhersion IS-101 –Part5- Sec 2
12 Flash Point IS-101 –Part1- Sec 6
13 Volume Solids IS-101 –Part8- Sec 6
14 Phthalic Anhydride content IS-101 –Part8- Sec 4
15 Accelerated Storage Stability Test IS:8662:2004
16 Resistance to Acid and Alkali IS:8662:2004
17 Volatile Matter S-101 –Part2- Sec 2
18 Hardness Test – Pressure Test IS-101 –Part5- Sec1
19 Acid Value IS-101 –Part9- Sec1
20 Rosin Test-Liebermann starch test IS-101 –Part9- Sec2
21 Ash Content IS-101 –Part8- Sec3
22 Pigments and Non-Volatile Matter IS-101 –Part8- Sec2
23 Residue on Sieve IS-101 –Part8- Sec1
24 Resistance to Heat IS-101 –Part7- Sec3
25 Resistance to humidity under condition of condensation IS-101 –Part6- Sec1
26 Film Thickness – Method – 3t IS-101 –Part3- Sec 2