|Form||Low slump semi stiff mastic compound|
|Physical or Chemical Change||Dries by solvent release|
|Application Temperature||5-50deg C|
|Temperature Range In Service||-20-80deg C|
For sealing joints in retaining walls, roofing (sealinghorizontal chases, flashings, gutterings and sheet laps),sealing terminations of bitumen based waterproofingmembranesAdvantages
- Firm, flexible weather resistant seal
- Excellent slump resistance
- Suitable for permanent immersion in waterCompatible with asphalt or bituminous surfaces
- Resistant to alkalis and sulphates
- Easy to apply
A flexible, gun applied sealant based on a combination ofbitumen and synthetic rubber. Dries to form a rubbery sealwith excellent slump resistance. Nitoseal MB175 has goodresistance to biodegradation, and is suitable for sealing lapjoints in gutters and drainage channels where ponded watermay reside. Also suitable for general sealing or pointing workin roofing and flashing applications.Design Criteria
Joint configurationJoints should be of a size to permit adequate application ofNitoseal MB175. Very narrow joints are difficult to sealeffectively and for most applications 10 mm should beconsidered as minimum width. Maximum joint width shouldnot exceed 40 mm. A minimum seal depth of 15mm shouldbe maintained.
Movement accommodation factorJoints should be designed so that total cyclic movement in tension or compression does not exceed 10% of the joint width at time of sealing. Total movement in shear should not exceed 20% of joint width at time of sealing.Application InstructionsJoint preparation
Ensure joint surfaces are completely dry, clean and frost free. Joint backing must also be dry. Remove all dirt, dust, laitance and loose material by vigorous wire brushing.Remove all rust, scale and loose surface coatings from metal surfaces. Remove any oil or grease with Solvent 10.Where a neat joint finish is required, cover the joint face edges with masking tape before Nitoseal MB175 application and remove the masking tape immediately after the sealing work has been completed.Priming porous surfacesNon-moving joints normally do not require use of primer, however excessively porous surfaces or friable surfaces may need priming. Consult Parchem for advice. Priming non-porous surfacesNot normally required. Where necessary, metal surfaces should be cleaned using Solvent 10. Ferrous metals should be treated with an anti-corrosion primer.Application
Nitoseal MB175 may be applied by gun direct from the cartridge or by trowel. When loading sausage into gun ensure nozzle is cut to the required length and angle, and that the sausage membrane has been punctured.Hold gun firmly against joint at a constant angle of about 45°. Guide nozzle along the joint gradually, ensuring good contact with joint surface. Never pump the trigger hard. Wipe the nozzle occasionally to ensure a clean extrusion.After sealant has been applied, it should be tooled to a slightly concave surface with a wooden spatula, which may be moistened with White Spirits or similar solvent.
Clean upTo be removed from equipment immediately after use with a solvent such as Solvent 10 or White Spirits. Do not use solvents on hands, use suitable proprietary skin cleaner.Water immersionNitoseal MB175 is suitable for permanent immersion in water, however, it is essential to allow full solvent evaporation from sealant prior to water immersion. This will take about 14 days at 20°C, longer if temperatures are lower or the Nitoseal MB175 is deeper than 20 mm.MaintenanceMechanical damage may be repaired at any time - ensure that surface is clean, dry and free of foreign matter to allow good adhesion of new to old Nitoseal MB175.Storage
12 months, stored in cool dry conditions in original, unopened containers when kept in dry conditions between 5°C and 27°C.