What is the dew point? People with what common condition should avoid isocyanates? What is laitance? How long should you shake an aerosol paint can? What is the shelf life for most paints? Amplitude is a measure of what? How long should you leave a newly-painted swimming pool before filling? [see answers below]

These and other questions are answered in an online Knowledge Base for professional paint users and specifiers, developed by independent paintmaker HMG Paints. With a market history dating back almost 75 years and the collective experience of its paint technicians and chemists, HMG felt it appropriate to publish its most Frequently Asked Questions, to help customers solve niggling queries and check up on critical points.

The Knowledge Base is at www.hmgpaint.com and it’s just a question of logging in, obtaining a password by return and clicking on the various categories. At present these cover everything from British and International Standards numbers, to spray gun set-up and surface preparation, with all the factsheets presented in easily printable Acrobat format. What’s more, HMG challenges the trade to come up with other paint-related FAQ’s, so the Knowledge Base can continue expanding.

Among the material available online are a theoretical paint coverage chart, an outline of the current isocyanates code of practice, an explanation of accelerated weathering tests and a factsheet on coverage rates and overcoating schedules, as well as a simple Centrigrade-Fahrenheit conversion table.

There’s a fairly comprehensive document on surface preparation and product application, covering steel, aluminium, woodwork, masonry, concrete and previously-painted substrates, plus a separate sheet devoted to galvanised steel. Also featured is a guide to painting swimming pools, with a warning about proper preparation and application, and another about coating concrete floors.

HMG also offers users the resource of its R&D laboratory for identifying and counteracting difficult-to-overcoat substrates and finishes, as well as the services of its QA department for updates on current BS, ISO, EN, ASTM and other technical standards.

Further enquiries to:

HMG Paints
Riverside Works
Collyhurst Road
Manchester
M40 7RU
Telephone 0161 205 7631
email sales@hmgpaint.com

Answers: Dew point is the temperature at which condensation starts to form. Asthmatics should avoid processes involving isocyanates. Laitance or efflorescence refers to the residual salts left after concrete has dried. Shake the can for a minimum of 2 minutes to fully mix the contents. The shelf life for most paints is 12 months in cool, dry conditions. Amplitude is a measurement in microns of the difference between the peaks and troughs in a metal surface. It’s best to leave a newly-painted pool around 2 weeks before filling with water.

Press Contact David Gent Creative
Tel 01706 220388
Fax 01706 215849
email david@davidgent.com

Frequent automatic brush washing can be detrimental to vehicle paintwork, the scratching and minor abrasions caused by rotating plastic brushes leading to considerable gloss reduction over time. Add road dust and grit into the watery mix and they literally take the shine off automotive topcoats.

Now, innovative, independent British paintmaker, HMG Paints of Manchester, has developed a self-healing topcoat system, which actually recovers from scratches and blemishes, restoring the original shine. Called Recover and believed to be unique in its formulation, this self-healing, highly scratch-resistant coating is ideal for the bus and coach market, where vehicles typically go through brush washes every day, as well as truck and automobile finishing and refinishing applications.

Recover is a clear 2-pack isocyanate cured polyurethane coating, which is spray applied over any HMG basecoat system, available in virtually any colour. Not only is this remarkable coating self-healing, it is also ‘water clear’, which means no slight yellowing effect, highly accurate shade matching and excellent colour retention.

“Most bus and coach operators are highly image conscious, as are many CV fleet owners, and like to have their vehicles looking pristine on the road,” says HMG’s Sales & Marketing Director, Stephen Falder. “We believe there is tremendous market potential for this product, which represents a genuine technical breakthrough, and have already trialled it successfully with bus companies and manufacturers. Experienced professionals looking at six month old paintwork actually believe it’s newly resprayed. Yet there will be no significant cost premium on this two-component PUR coating.”

As one of the last independent British manufacturers of automotive coatings and a leading supplier to the UK bus and coach industry, HMG Paints is continually researching and developing new paint systems at its Collyhurst Road site. In order to come up with a solution to an age-old market irritation, the degradation of gloss finishes caused by brush washes, the company’s R&D department recently conducted extensive laboratory testing of scratch-resistant automotive clear coats, in the process developing the formulation for Recover.

Automotive clear topcoats are required to possess a number of performance characteristics, including toughness, durability and excellent resistance to chemicals and scratching. Market experience has shown that polyurethane (PUR) coatings based on aliphatic isocyanates are superior to conventional finishes in this respect, although even with these coatings there is traditionally a compromise, in that any increase in scratch resistance was generally accompanied by a decrease in chemical performance. However, HMG’s paint technicians reasoned that, given the many options for modifying the chemical structure of PUR coatings, there was a great deal of scope for further performance optimisation.

The company then conducted an extensive series of tests to determine the detailed characteristics of scratch resistance at all stages of binder and coating development, using image analysis techniques and microhardness measurements. Since existing studies showed that scratching of vehicle bodies in automatic brush washes is primarily caused by sandy dirt particles, this process was recreated in a laboratory brush wash simulator by adding quartz sand to the water and washing test panels coated with various 1K and 2K polyurethanes, then examining the results.

Scratching subjects the coating to considerable localised mechanical stress and any recovery starts shortly after stress removal, due to the viscoelastic deformation behaviour of polymer networks, known as ‘reflow’. Such in-depth analysis led to the formulation of Recover, a flexible, yet tough and durable 2K PUR coating, which possesses optimum chemical and scratch resistance characteristics, as well as inherent self-healing or ‘reflow’ properties.

This self-healing nature allows the paint film to recover and obscure any minor marks and scratches caused by mechanical washing, within a time period of anything from 5 minutes to an hour or so, depending on severity. To demonstrate this effect, HMG has even produced sample Recover-coated panels, which technical and sales personnel can abrade with Scotchbrite pads and allow customers to see the coating recover before their eyes.

HMG’s Recover can be sprayed with conventional or HVLP equipment, then force cured at up to 60ºC, with drying times comparable to conventional 2K PUR coatings. HMG Paints has also developed appropriate polishing techniques for this unique clear coat, in association with automotive specialists Autoglym, Farécla and 3M.

Further enquiries to:

HMG Paints
Riverside Works
Collyhurst Road
Manchester
M40 7RU
Telephone 0161 205 7631
email sales@hmgpaint.com

Press Contact David Gent Creative
Tel 01706 220388
Fax 01706 215849
email david@davidgent.com