Paint Coating Testing

METS evaluate all the physical and chemical properties of various paints and coatings that are applied to certain bulk materials to improve their surface properties. We follow different international standards as per the manufacturers and end-user’s requirements following the application procedures for the coating of their concern. Below are the few tests among them. Further our R&D department customize/develop testing as per the client requirements.

Abrasion Resistance

This test helps in determining the ability of a coating to resist degradation due to mechanical wear by hard and rough objects. Abrasion resistance can be enhanced by incorporation of surface modifying additives.

Adhesion

Adhesion testing in the paint and coating industries is necessary to ensure the paint or coating will adhere properly to the substrates to which they are applied.

Alkali Resistance of Paint

This test helps in determining the degree to which a paint resists reaction with alkaline materials such as lime, cement, plaster, soap, etc.; a necessary property for paints in bathrooms, kitchens, laundries.

Cass Test

This test helps in determining the corrosive performance of decorative copper/nickel/chromium or nickel/chromium coatings on steel, zinc alloys, aluminum alloys, and plastics designed for severe service. It is also applicable to the testing of anodized aluminum.

Chemical Resistance

This test helps in determining the ability of a coat to resist chemical deterioration or staining.

Chip Resistance

This test helps in determining the resistance of surface coatings (paint, clear coats, metallic plating, etc.) to chipping caused by the impacts of gravel or other flying objects.

Coating Hardness

This test helps in determining the hardness of paint coat.

Coating Surface roughness /Profile

The proper and effective preparation of a surface prior to coating is essential. Making sure that the correct roughness – or profile – has been generated is essential. If the profile is too low, the adhesion of the coating to the surface will be reduced. Too high and there is the danger that the profile peaks will remain uncoated.

Coating Thickness

This test helps in determining the thickness of paint plating, coatings and galvanizing on iron steel.

Condensing Humidity

This test helps in determining the resistance of organic coatings by controlled condensation. Condensation is produced by exposing the test surface of the sample to a heated, saturated mixture of air and water vapor, while the reverse side of the sample is cooled to room temperature air.

Crosshatch Adherence

This test helps in determining the adhesion of a large variety of coatings.

Cyclic Corrosion

This test helps in determining the corrosion degradation of coating systems for steel bridges.

Drying Time

This test is done to know when a coating is totally dry. When developing a process, it is often important to know the exact time it takes for the coating to dry or cure. There are many stages to the coating drying time. Once a coating has been applied, the first stage is that the coating levels off under gravity. Once a coating begins to cure, a thin dry film appears on the surface. The coating then continues to dry and finally after a period of time, the coating is totally cured.

Failure Analysis

This test helps in determining when, where, and how the paint or coating failure occurred.

Falling Weight

The ability of a pipe coating to resist mechanical damage during shipping, handling, and installation will depend upon its impact resistance. This test method provides a systematic means for screening coating materials with regard to this property.

Flexibility

This test helps in determining the ability of a coating system to withstand the stresses of fabrication. Organic coatings on precoated sheet are subjected to stresses when fabricated into products by roll forming, brake bending, or other deformation processes. These stresses can exceed the flexibility or adhesive strength of the coating, resulting in fracture of the coating which exposes the substrate, or in the loss of adhesion of the coating to the substrate.

Free Falling Sand Abrasion

The abrasive is allowed to fall from a specified height through a guide tube onto the coated panel until the substrate becomes visible. The amount of abrasive per unit film thickness is reported as the abrasion resistance of the coating on the panel. Both silica sand or silicon carbide can be used.

FTIR

FTIR, which can serve as an important “first-line” analysis tool for the identification of coating types and drying mechanisms via monitoring of the functional groups on the chemical compounds inherent in the formulation.

Gloss (60deg.C)

Gloss measurement is essential instrument where a cosmetic appearance of the coating finish is required. It measures, guide to control and test right from matt to mirror finish accurately. Multi directing a beam light at a specific angle to the test surface and measuring the amount of reflection determine gloss. For general gloss measurement the 60º angle is recommended.

Hardness

This test method covers a procedure for rapid, inexpensive determination of the film hardness of an organic coating on a substrate in terms of drawing leads or pencil leads of known hardness. This test covers the determination of the indentation hardness of organic materials such as dried paint, varnish and lacquer coatings, when applied to an acceptable plane rigid surface, for example, metal or glass.

Impact resistance

Impact performance after painting/printing can be tested with several impact tests, like a puncture test or a falling dart test.

Moisture Content

This test helps in determining the total water content of paints using a calcium hydride reaction test kit, or water content between 2 and 85 % water.

Peel

This test is used to measure resistance to cracking (flexibility) and adhesion of attached organic coatings on substrates of sheet metal or rubber-type materials.

Penetration Resistance

The penetration resistance is of special importance to architectural finshes. The ability to maintain a uniform appearance (color and gloss) on substrates with varying porosity can be evaluated by applying the paint over a test chart which has a coated and uncoated area. Thus, the penetration resistance is tested under severe conditions. The penetration resistance is visually evaluated and can also be objectively evaluated by measuring color and gloss.

Salt Spray

The salt spray test is a standardized test method used to check corrosion resistance of coated samples.

Scratch Resistance

The scratch resistance can be established e.g. in the Taber abrasion test, where the amount of haze is established after a number of abrasive cycles. The scratch resistance can also be determined quantitatively by measuring the weight loss after a number of sanding cycles. The pen test determines the indentation caused by a sharp pencil applied with a defined force.

Scrubbing Resistance

This test helps in determining the resistance of paints to erosion caused by scrubbing. Although scrub resistance tests are intended primarily for interior coatings, they are sometimes used with exterior coatings as an additional measure of film performance.

Spark Testing

One of the most important properties of a thin film coating is the adhesion (interfacial forces between two surfaces) between the coating and the substrate. The most common method of accurate measurement of thin film coating adhesion is the scratch tester.

XENON Arc

This test helps in determining the ability of a paint or coating to resist deterioration of its physical and optical properties caused by exposure to light, heat, and water can be very significant for many applications. This practice is intended to induce property changes associated with end use conditions, including the effects of sunlight, moisture, and heat. The exposure used in this practice is not intended to simulate the deterioration caused by localized weather phenomena such as atmospheric pollution, biological attack, and salt water exposure.

Volatile Content

This test helps in determining the weight percent volatile content of solvent-reducible and water-reducible coatings.

Water Content

The amount of water that paint coat could absorb is measured by the water content test.

Water Resistance

Water can cause the degradation of coatings, so knowledge of how a coating resists water is helpful for assessing how it will perform in actual service.

List of Test in Paints/Coatings

  • Salt Spray Test
  • Light Reflectance Value
  • Solar Reflective Index
  • Weathering Resistance
  • Stain Resistance
  • Emission of VOC and Formaldehyde
  • Chloride ion diffusion
  • Asbestos content in paint
  • Cathodic disbandment testing
  • Pull of Strength
  • Specific Gravity
  • Crack Bridging Ability
  • Aromatic Hydrocarbons
  • Anti-Fungal Resistance
  • Anti-Bacterial resistance
  • Microbial condition of paint in the can and raw material
  • Fire Propagation
  • Flame Spread
  • Water content
  • Fineness of Grind
  • Water Resistance
  • Chemical Resistance
  • Shore A Hardness
  • Pigment content
  • Reduction in Chloride Ion Penetration
  • Poly Chlorinated Biphenyls
  • Formaldehyde emission
  • Viscosity
  • Tensile Strength
  • Non-Volatile Content
  • Volume Solids, Weight Solids
  • Abrasion Resistance
  • UV Resistance
  • VOC
  • Washability and Scrub Resistance
  • Reduction in Water Absorption
  • Finger printing of paint- FTIR
  • Di Electric Strength
  • Drying Time
  • Flexibility
  • pH
  • Heavy Metals
  • Impact Resistance
  • Adhesion
  • Impact Resistance
  • CO2 Diffusion
  • Titanium dioxide
  • APEO content
  • Flash Point
  • Halogenated hydrocarbons