The appearance of ‘blisters’ and resultant ‘craters’ may be experienced during, or shortly after, the application of certain epoxy coatings inclusive of LUXAPOOL EPOXY FINISH.

WHEN ARE BLISTERS MOST OFTEN EXPERIENCED?

The development of blisters will normally be limited to the warmer months, and more frequently experienced in tropical and subtropical zones. They will also be more likely to occur from mid morning thru’ to late afternoon even in temperate zones. Blisters are also more likely to occur during application of a ‘first coat’ as opposed to following coats.

WHAT INFLUENCES THE DEVELOPMENT OF BLISTERS?

There are two primary causes of blister development, and both are more commonly experienced, but not limited to, epoxy coatings which contain some percentage of volatile hydrocarbon solvents. Blisters may occur when air pockets in a porous substrate are subject to warming by sunlight. They will thus expand, and finally break through the surface. Also blisters can occur when the epoxy surface undergoes ‘primary cure’ before all solvent is released from the coating. The escaping solvent, drawn to the surface by sunlight and heat, ‘ruptures the surface’ as a blister.
In both incidences, and dependant on the state of surface cure, the blister may rupture and form a crater, or ‘void or defect’ in the surface.

HOW MAY THE INCIDENCE OF BLISTERS AND CRATERS BE REDUCED?

Applicators should follow the general guidelines:

  • Ideally work below a shade-cloth which will moderate direct sunlight onto the surface.
  • If pool surfaces cannot be shaded, schedule application for late winter into early spring.
  • Commence application as early as practicable in the morning, but no later than mid-morning such that surfaces are as cool as possible when coated.
  • Commence application on the pool side that has been exposed longest to the sun (western edge), then work to the south edge, then to the east, to the north and finally onto the floor.
  • For porous cement render or marblesheen surfaces especially, apply LUXAPOOL EPOXY PRIMER-SEALER as the initial coat.
  • Avoid application of ‘thick coats’, rather use spread rates of 23 > 24 m2/pack as opposed to 20m2/pack in more temperate conditions. Also focus on filling any observed surface porosity using a ‘stronger rolling action’.

EARLY REPAIR OF BLISTERS OR CRATERS:

Lightly ‘roll down’ any observed blisters using an ‘almost dry small roller’ as each pool side is completed. Same as for the base as the applicator works back to towards the exit stairs.

When exited the pool, and before leaving site repeat the procedure using an appropriate extension handle if needed. Repeat blisters are unlikely to occur beyond this time.

POST CURE REPAIR OF BLISTER, CRATERS AND SURFACE VOIDS:

  • If not in the final coat, sand smooth and dust off within 24 hours, and before next coat application.
  • If in the final coat, and only if of concern with respect of the quality of the final finish, sand smooth with ~ 150 grit paper , dust off and ‘spot in’ with fresh LUXAPOOL EPOXY FINISH ( available as a 1 ltr pack from Brookvale stocks).

VER1406
The technical advice and/or application advice given in this publication represents the present state of our knowledge, and is believed to be reliable. Buyers and intended users of all Colormaker Industries products should read the TDS carefully and then conduct their own assessment to confirm the suitability of the product, including in conjunction with other products, and the types of surfaces to, and the manner in which, the product will be applied. Colormaker Industries offers no warranty of performance based on the above information, either expressed or implied.

Download LUXAPOOL Blisters & Craters in Epoxy Coating Tech Data Sheet 1406