Epoxy colored sand flooring, as a seamless and integrated composite decorative flooring, balances functionality and decorativeness. Its core challenge lies in the “balance between wetting and curing under high filler content”. By dissecting the component selection logic, this article discusses one of the key preparation points for high-performance solvent-free epoxy colored sand flooring coatings.

01 Analysis of difficulties in epoxy colored sand flooring

Epoxy Quartz/Epoxy Terrazzo differs from self-leveling (which does not contain millimeter-sized particles) in terms of technical positioning, and it is also not a mortar coating (which relies on filler accumulation for leveling). Its core feature is a high-solid content slurry consisting of approximately 70% millimeter-sized colored aggregates (sand particles) and micron-sized calcium powder and barium sulfate fillers. The resin fills the gaps between the aggregate fillers and bonds to substrates such as cement, balancing functionality and decorative performance, while requiring high aesthetic and practical performance.

 

The characteristics and performance advantages of solvent-free epoxy color sand flooring determine its formulation logic, which is significantly different from that of epoxy self-leveling. One of the key technical challenges is:

Solve the problem of fully wetting the aggregate at a high filling rate of 70%

The various excellent properties of epoxy colored sand flooring, such as strength, wear resistance, water resistance, and chemical resistance, are highly dependent on whether the surface of the sand particles can be fully wetted, the air between sand particles can be eliminated, and a continuous bonding phase can be formed after curing. Insufficient wetting will lead to a significant decrease in three properties of the paint film:

▶  There are micro-pores at the sand-resin interface → Water/chemicals penetrate along the interface → Water resistance/chemical resistance decreases;

▶  The sand grains are not fully encapsulated → “exposed sand” on the surface → obvious shedding of sand grains during abrasion rather than uniform wear.

▶  Stress cannot be effectively transmitted → compressive/flexural strength significantly decreases

Wetting schematic diagram of epoxy colored sand floor

 

At high filling rates, micron-sized fillers such as calcium powder and barium sulfate will preferentially adsorb the curing agent and reactive diluent in the resin. The resin with further increased viscosity can no longer easily “flow freely” to the surface of each sand particle, but instead penetrates between the sand particles through capillary effect. Moreover, there are many risk factors affecting the wetting of sand particle surfaces, such as clay on the surface of natural sand, bubbles during preparation, and stable bubbles brought by surface activity. The increase in porosity between sand particles can lead to stress concentration and the formation of weak interfacial zones, both of which weaken the compressive strength.

High-end epoxy colored sand floor coatings should fully address the aforementioned technical challenges and exhibit a range of excellent quality and performance characteristics (some examples):

 

02  Epoxy flooring auxiliary agent

The incorrect selection of surfactant may enhance foam stability and reduce bonding strength, making the correct choice crucial. With over 20 years of experience in the research, development, and production of additives, we are pleased to offer you a cost-effective industrial-grade epoxy colored sand flooring solution.

In practical testing, this solvent-free epoxy colored sand floor coating exhibits no visible air bubbles after thick application, and demonstrates good workability and fluidity. Even in thinner corners (where application is uneven), it ensures wet adhesion of sand particles, effectively reducing the void ratio. During subsequent storage, no hard lumps or agglomeration occurred.

In the formula, 0.5% Tech-598 can quickly wet about 70% of the aggregate filler surface, reduce the coarsening and flocculation of calcium powder and barium sulfate, and significantly reduce viscosity; 0.3% Tech-214N has a moderate ability to reduce surface tension, can improve the flatness of the slurry, promote resin penetration, and has good low-temperature foam stability, making it suitable as a defoamer in some systems; 0.20% Tech-31055 defoamer contains a foam-breaking factor, which can quickly break bubbles, eliminate tiny bubbles in sand grain gaps, and significantly reduce the void ratio.

 

03 Summary

The epoxy colored sand flooring auxiliary agent supporting scheme provided this time is zero VOC and more environmentally friendly. The colored sand coating prepared by the scheme is seamless and dense overall, fully wetting and wrapping the colored sand. It has sufficient conditions for high resistance, compression resistance, and impact resistance. The dry film is smooth and bubble-free, effectively reducing the impact of high porosity on the acid and alkali resistance, oil resistance, and waterproofing of the dry film.