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Brief descriptions of key words and products found on our website


A non-metallic substance used to bond or hold two or more pieces together. May be permanent or temporary.

Adhesion Test

A test to check the adhesion of a coating to a substrate. A typical test would be ASTM D 3359 Test Method B. Adhesion is assessed on a scale of 0 to 5, with 0 being the worst result and 5 the best with perfect adhesion.


An acrylic resin is a thermosetting or thermoplastic substance. It is considered weatherproof and does not yellow when exposed to sunlight. Derived from acids such as acrylic acid.


Algae are a diverse group of aquatic organisms capable of producing Oxygen through photosynthesis. Ranging from seaweeds to algal blooms in lakes and ponds, they can be found in both seawater and fresh water.


A modified Polyester, they tend be to most common resin within so called oil based coatings. The length of the oil chain in the resin will vary the coating properties.


A soft, non-magnetic metal in common usage. When used as flakes within coatings it helps give improved corrosion resistance by increasing the pathway any corrosive liquid has to take.


The process or technique whereby a coating prevents or minimises aquatic growth on submerged equipment such as boat hulls. The Blocksil anti-fouling coating works by repelling barnacles rather than by killing them.


A naturally occurring mineral once extensively used for its heat resistant properties. Highly hazardous, these days the preference is to manage it rather than remove it.

Barrier Protection

A coating that gives barrier protection will typically be impervious to corrosive liquids.

Bellows / Gangways

The flexible connector between railway (or bus) carriages. Made of specialist fabrics they do suffer from vandalism and wear, both repairable with a Blocksil coating that will withstand fatigue for 500,000 cycles.


The application of materials over another. Also the name given to the product itself, such as that found on the faces of buildings.

Coating (or paint)

A covering, usually a liquid, applied to a substrate to give the substrate a functional and / or a decorative finish. The coating can be made up of a number of layers.


A natural process that is the gradual destruction of a material, usually by chemicals, within their environment. Corrosion can be accelerated.


A product designed to remove grease from a substrate.

Drop Test

Where a known and prescribed weight is dropped a known and prescribed height onto a coated sample panel. The test helps assess the strength and structural integrity of the coating.


Originally describing oil based coatings, enamel coatings may now include Alkyd resins. They tend to be air drying coatings that give a hard, glossy finish.


A widely used resin which may be reacted with themselves or a curing agent to give a tough, protective coating. There are a wide range of curing agents used which will vary the coating’s properties. Prone to yellowing over time when exposed to UV radiation.

Etch Primer

A special type of primer that uses a mild acid to etch the substrate to aid or effect adhesion. Typically with low corrosion performance when left on its own so overcoating is essential.


A woven material made from threads such as cotton, nylon, silk etc. Used for clothes, furniture, coverings etc.


Where a component fails through repeated bending. Such bending may be from vibration or everyday use.

Fire Test

A test to determine what happens to a coating in a fire. There are different test standards used by different industries but all will look at what is given off by the coating and whether the coating supports or aids fire.

Flame / Fire Retardant

Chemicals that are added to materials to prevent the start of a fire (or to slow the fire down).


A non-woven fabric with an open weave. Used as reinforcement for some coatings.


A polymer based around the Fluorine atom, this family of coatings are most well known for their non-stick properties when sold as PTFE. Can also provide excellent corrosion resistance.


A chemical compound that kills fungi or their spores.


Usually used to describe the unwanted and unauthorised painting of a public space. The paintings are most often stylised symbols but can be either end of the spectrum, from offensive to decorative, such as those created by Banksy.


In its purest form Graphene has a molecular structure comprising of a single layer of Carbon atoms bonded in a hexagonal structure. Graphene possesses an unsurpassed combination of mechanical, electrical and thermal properties.


A coating based on two or more different chemistry coating types resulting in a finished product whose performance is greater than the sum of the individual coatings.


Such a coating repels water. The contact angle between a water droplet and the coating is typically greater than 90o.


Such a coating will attract water. The contact angle between a water droplet and the coating is typically less than 90o.


Electromagnetic radiation whose wavelengths are longer than those of visible light. Humans cannot see infrared light but they can feel it as heat.


Based on chemistry not containing Carbon.


A coating or sealant that swells when subjected to fire. The increase in coating thickness gives an increase in volume and decrease in density. Combined with the creation of char products, which are poor heat conductors, this helps reduce the fire spread.


The building of a structure and a term also given to the individual components, such as bricks, stones and concrete.


A thick sealant commonly used from a tube to seal gaps. Used throughout the construction industry, the mastic can be made from a wide range of materials, such as rubber, Silicone and even vegetable oil.

Nano coatings

Very thin film coatings, usually less than 5 or 6 microns thick, they can provide easy clean and abrasion resistance to existing coatings, metals and a range of other substrates.


Based on Carbon chemistry.

Paint (or coating)

A covering, usually a liquid, applied to a substrate to give the substrate a functional and / or a decorative finish. The paint can be made up of a number of layers.


A photocatalytic coating absorbs light to make a chemical reaction occur within the coating. An example would be to allow the coating to take up Nitrogen Oxides from the surrounding air.


The technical term for colour fading. The colours we can see are based on which colours (wavelengths) the paints or coatings absorb as well as the nature of the chemical bonds holding the paint or coating together.


Typically organic materials derived from cellulose, oil, coal etc. A huge family of materials some of which are fully biodegradable.


A relatively new hybrid material with a resemblance to Polyurethane, these polymers are UV and light stable with a low tendency to yellow.


A synthetic material which is quite durable and, at a molecular level, tightly crosslinked. Thus it is useful for corrosion resistance.


Silicon based polymers, they are chemically stable, very hydrophobic and have a low moisture uptake. Good electrical insulation is another characteristic.


An organic coating which can either be a thermoplastic or thermoset. The most common use for Polyurethanes is as a foam. As a coating it is hard wearing and easy to clean.


The first coating applied, usually to achieve specific properties such as corrosion resistance or enhanced adhesion prior to application of the rest of the coating system.


A coating or treatment for fabrics or masonry so as to make them impervious to water, staining or oils.


This is the base of the coating. To the resin are added the colours, solvents, UV stabilisers and so forth to create the actual coating.


Oxides of Iron, created when Iron is in the presence of Oxygen and water. Whilst rusting is shorthand for any metal corrosion, it truly only applies to Iron based metals such as steel. Blocksil offers a Rust Remover and also a Rust Converter that converts Iron Oxide to Iron Phosphate ready for coating.


A coating used to prevent the passage of liquids through pores and openings in the substrate. Some sealers have a chemistry that will help prevent the growth of algae.


A combined inorganic – organic hydrophobic polymer with low thermal conductivity, low toxicity and resistance to microbiological growth. Not to be confused with Silicon, which is a chemical element.

Slip Test

A test to determine how much grip a coated surface has. Essential for coatings that will or may be walked upon.


In a coating sense, a liquid into which other materials will dissolve. A solvent can be as simple as water.


A structural metal used extensively throughout many and varied industries. Has a wide range of formulations, from very simple to more complex corrosion resistant stainless and duplex steels.


A polymer than when solid can be softened by heat. It can often be reused.


A polymer that when solid or cured cannot be softened by heat.


A liquid compatible with the coating and used to make it thinner, usually for ease of application.

Top coat

The final layer of a coating system. It may be purely decorative, purely functional or a combination of both.

UV radiation

Electromagnetic radiation with wavelengths shorter than visible light, it will degrade untreated coatings and organic matter. UV-A radiation (at the longer wavelength end of the UV spectrum) will dry out the resin in a paint or coating leading to cracking.
UV-B radiation leads to a fading or loss of colour of the paint or coating by breaking down it’s chemical bonds.

Vinyl Coating

A coating based on synthetic resin or plastic. It has good colour and gloss retention when exposed to UV light and gives excellent barrier protection against corrosion.

Blocksil Limited
Cathedral House
5 Beacon Street
Lichfield WS13 7AA
T: +44(0)1543 887 840
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