What is DriPHOS TLT ?
DriPHOS TLT is a one tank process for metal cleaning, priming and surface treatment. A development of the vapour degreasing process it uses solvent to replace water based multi tank systems.
What metals can be processed with DriPHOS TLT ?
Any metal or mixture of metals can be processed. DriPHOS TLT is most effective with mild steel and iron or other ferrous metals because the protective crystalline coating overcomes the problem of flash rusting but the etching primes the surface and exceptional cleaning of all metals ensures the highest quality final coatings. The process is optimised for your components when the tank is commissioned.
What does TLT mean?
TLT stands for thin layer technology. This is exclusive to Envirotech Surface Technologies and is a coating of a nano crystalline structure which is grown on the metal surface. It is part of the metal and flexes with the metal instead of shearing like some conventional pre-treatment coatings. The crystalline structure primes the metal surface increasing the surface area dramatically for improved adhesion of the subsequent finishes such as paint or powder.
Does DriPHOS TLT improve corrosion protection?
Yes the improvement in adhesion is similar to that given by multi tank water based processes but the crystal matrix is more regular and by improving adhesion prevents corrosion below the paint surface. As a solvent based process no water is involved so parts are completely dry after processing and will not rust for periods of up to a year in storage. This improves productivity and reduces costs as long runs of components can be produced, processed and stored awaiting final assembly and finishing.
Why is improved adhesion important?
Cost and weight savings particularly on domestic appliances, metal furniture, seating, cabinets manufactured in sheet metal and tubular steel demand reductions in the thickness of metal used in manufacture. Application of one coat paint finishes require exceptionally clean and primed metal which give maximum surface area for the paint to adhere to. DriPHOS TLT meets these needs producing a nano thickness crystalline layer not bonded to the metal surface but an integral part of it offering a massive increase of “keying” for the final coating. In use any impact damage can dent or scratch the metal which may lead to delamination with other types of surface pre-treatment allowing the paint or powder film to be shed exposing metal to rust or corrosion. The thin layer technology used in the DriPHOS TLT process overcomes this problem as it flexes with the metal.
Why should I use DriPHOS TLT ?
DriPHOS TLT is a one tank process which uses a very small area of factory space releasing production area to earn you money. We use height which you do not pay for in rent or rates. It is very quick, generally process time under ten minutes per basket. Parts are cool and dry when emerging from the process and can be handled immediately. Operating temperature is very low 38C so the process is energy efficient and uses very little product. Machines are simple and if you are using or have used vapour degreasing will be familiar but because of the improved machine design much safer in use. Superb adhesion and improved corrosion protection. Why would you not use it?
Is DriPHOS TLT considered to be safer than trichloroethylene (TCE)?
Yes dichloromethane the main constituent has an official WEL (Workplace Exposure Limit) of 100ppm (EH40/2005) ETE consider this to be safe for operators for long term exposure and is easily achieved by equipment designed for the DriPHOS TLT process.
Are all the substances used in formulating DriPHOS TLT pre-registered for REACH?
Yes, all the constituents used to produce DriPHOS TLT have been pre-registered for the REACH registration process. Full registration of these will take place as this legislation proceeds.
How does the Solvent Emissions Directive affect the use of DriPHOS?
DriPHOS TLT is a solvent based surface treatment. Equipment designed for the DriPHOS TLT process operates within the regulatory limits.
Is DriPHOS TLT flammable?
NO - DriPHOS TLT as supplied and used in properly maintained baths is non flammable. Refer to the Safety Data Sheet and Technical Data sheet for safe working practices
What’s wrong with water based surface treatment systems?
Nothing. Some customers will prefer to use water based systems and we respect these views and working with our equipment partners we have developed a one tank process, AQUUS TLT which is equally convenient and easy to use as a solvent system. However solvents do offer many advantages for processing which we discuss further to help you make informed decisions.
Comparing Solvents versus Water for surface treatment?
Water is more environmentally friendly!
Not necessarily, On its own it will not be able to clean metal and apply a protective coating without adding other chemicals. Ionic and anionic surfactants to release the soils and dissolve oils and grease, acids to etch and prepare metal surfaces for conversion, stabilisers and other chemicals are needed in these formulations. During processing an excess of crystals are produced forming a complex sludge which needs to be removed regularly with expenses involved in disposal. Rinse water also adds to the load on the environment as it must be treated before disposal to drains. Most often these sludges will contain phosphates which are food for algae which do cause problems in watercourses.
The environmental impact of heating for the bath and rinse water and most importantly the drying process must be considered as this can be at least 5 times as much as for a solvent system.
Flash rusting is often a problem. Because water is the process medium unless the crystalline coating is completely dry parts will rust or corrode very quickly. Painting or powder coating within a hour is essential.
Must be safer for operators as its only water?
Possibly but using DriPHOS TLT in the specially designed equipment exposure is extremely low and at levels where lifetime exposure will be perfectly safe. Remember the water based processes contain chemicals which can cause skin conditions due to removal of natural oils and need as much care in handling as solvents and as water based systems need more maintenance and bath changes exposure to these chemicals is likely to be more regular.
Are solvents in DriPHOS TLT environmentally friendly?
Yes dichloromethane the base material has no ozone depletion potential, no global warming potential and no soil and water persistence. It is safer for the environment when use in cleaning and pre-treatment systems as with an exceptionally high solvency it works at very low temperatures 38/40C and requires 5 times less heat for processing and drying reducing the environmental impact of CO2 in the production of electricity. DriPHOS TLT produces very little sludge compared to water based processes. These are captured in filter bags and are easily disposed of as dry waste. DriPHOS TLT equipment is designed to use minimal amounts of process liquids and emissions are strictly controlled.
Solvent or water it’s your choice.
If you need more information or would like to discuss the DriPHOS or Aquus TLT processes please Click here to contact us.
If there are unanswered questions or you have suggestions for further facts which should be a added, again please Click here to contact us. We look forward to hearing from you.
Last updated on 08/04/15