Resitech HD Screed
Description
Resitech HD Screed is a three component solvent free epoxy resin screed system designed to impart a highly abrasion and chemical resistant surface to treated substrates including steel and concrete.
It is resistant to a wide range of chemicals, and has been used as a protective floor covering in such situations as:
- workshops
- manufacturing areas
- water treatments plants
- deck plates
- food processing areas
Surface Preparation
Concrete substrates must be at least 28 days old and be clean, dry, sound and free of laitance, oil, grease and many other surface contamination which could impair adhesion.
Existing areas will require mechanical abrasion to reveal clean concrete. Enclosed vacuum blasting equipment should be used on steel. Vonarx type scabblers can be used on concrete. Any areas which have been contaminated with oil or grease should be treated with hot compressed air blasting equipment. This will drive out any deep seated contamination.
Any areas of damaged concrete should be broken out and reinstated. For small areas of thin section repairs - less than 10mm in depth - an epoxy resin mortar should be used. For larger areas thicker section repairs a polymer reinforced cementitious repair mortar should be used, and these repairs will have to be allowed to cure for some 5-7 days prior to overcoating with Resitech HD Screed.
Any existing floor coatings must be removed prior to the application of Resitech HD Screed.
For newly laid concrete which has been allowed to cure for the minimum 28 days, a light pass with enclosed vacuum blasting equipment is required. This will lightly texture the substrate and ensure that all laitance and the remnants of any curing membranes are removed. Areas not accessible to the blasting equipment should be prepared by a combination of vonarx scabblers, hand held diamond grinders and needle guns.
All dust and deleterious matter must be removed by vacuum prior to the application of the primer.
Any flexible joints within the concrete substrates should be protected with masking tape and brought up through the surfacing.
The perimeters of the areas being treated, along with any grids, drains etc. should be protected with masking tape.
Priming
Immediately prior to the application of Resitech HD Screed the substrate must be coated with an application of Resitech Primer PS, a two component solvent free epoxy resin priming system.
Resitech Primer PS is supplied in pre-weighed packages, and it is essential that all of the curing agent, pack A, is added to all of the resin component, pack B, and mixed thoroughly for 60 seconds with a mechanical paint stirrer.
When fully mixed the primer should be applied immediately to the prepared substrate by brush or roller. The Resitech HD Screed must be applied onto the primer “wet-on-wet” and must not - under any circumstances - be applied to the primer if it is allowed to cure tack-free. This will take approximately six hours at 20oC, and if allowed to happen the area will require re-priming. As a consequence, the size of area to be primed should be limited to that which can be screeded within six hours.
The coverage rate of Resitech Primer PS is dependant upon the texture and porosity of the substrate, but should fall in the range of 4-6m2/litre.
Mixing and Application
Resitech HD Screed is a three component system which is supplied in pre-weighed packages. It isessential that all of the curing agent, pack A, is added to all of the resin component, pack B, and mixed thoroughly in a forced action mixing vessel (examples include pennine, daines, mixal etc.) for sixty seconds. The grade filler component, pack C, is then gradually added whilst mixing continues for an additional three minutes.
The fully blended system is applied in one application at the specified thickness onto the wet primer by a steel trowel inorder to obtain a tight, uniform surface appearance.
At an ambient temperature of 20oC, Resitech HD Screed may be lightly trafficked after 24 hours, with 48 hours being required prior to heavier trafficking.
Coverage Rate
A 28.0kg unit of Resitech HD Screed will cover approximately 2.4m2 at a thickness of 5mm.
Technical Properties
- Tensile Strength: (BS 2782 pt 10) - 11.5N/mm2
- Compressive Strength: (BS 6319 pt 2) - 38.0N/mm2
- Flexural Strength: 27.5N/mm2
Chemical Resistance
Resitech HD Screed exhibits excellent resistance to a wide range of chemicals, and is fully resistant to the following:
- 10% Sulphuric Acid
- 10% Hydrochloric Acid
- Xylene
- Methyl Ethyl Ketane
- Petrol
- 20% Sodium Hydroxide
- Ethylene Glycol
- Trichlorethylene
- Pot Life (20oC) - 1 hour
- Primary Cure (20oC) - 12 hours
- Full cure (chemical resistance)(20oC) - 7 days
- Application Temperatures - 5 - 30oC
Please note that cure times and open to traffic times increase considerably at lower temperatures.
Cleaning
Tools should be cleaned with a hydrocarbon solvent before the initial cure has occurred.
Health and safety
It is recommended that barrier cream, gloves and overalls should be worn when using Resitech HD Screed. For full details please refer to the appropriate health and safety data sheet.
