Superior Stone and Tile Sealing with Capstone®

One of the best ways to maintain the value of residential and commercial real estate is by enhancing the appeal and longevity of the materials used to build these structures. Due to their beauty and durability, stone and tile are popular materials used to create walkways, walls, and surfaces.

Penetrating sealers are highly recommended treatments to adequately protect stone and tile from stains, corrosion, and mildew growth while preserving their natural look and beauty. To maximize the protection of stone and tile surfaces, Chemours has developed Capstone® repellents to offer market-leading penetrating sealer performance in water and oil repellency.

Capstone® Repellents for Penetrating Sealers

Capstone® repellents are fluoropolymers with linear fluorinated tail and polar head groups that are preferred active ingredients in penetrating stone and tile sealant formulations. Penetrating sealer formulations use carriers like water or solvents to penetrate and deliver the active ingredient in the upper layers of the surface. Capstone® repellents have extremely hydrophobic and oleophobic fluorinated tails that provide masonry superior repellence and resistance to staining from water and oil. The polar head groups on the polymer serve to anchor it to porous surfaces, orienting the polymer accordingly:

Capstone® polymers are based on short-chain C6 chemistry that meets the goals of the EPA 2010/15 PFOA Stewardship Program. Thus, Capstone® products are not made with PFOA and PFOS or used in manufacturing.

Penetrating sealers formulated with Capstone® have excellent performance when coating porous substrates. Thus, they are ideal for the following types of stone and tile:
 

•   Granite
•   Marble
•   Terra-cotta
•   Tile grouting
•   Porous tiles
•   Concrete
•   Sandstone
•   Saltillo

Capstone® Performance for Oil and Water Repellency

Capstone® provides better oil and water repellency and higher stain resistance than other repellants. As mentioned, it also does not alter the natural look of stone and tile and, since it is breathable and not film forming, allows moisture within stone and tile to escape. Thus, it is more effective at preventing staining from most household sources, accurately preserves the beauty of stone and tile, and helps prevent mold and mildew formation due to water that may enter the material from the sides.

The performance of penetrating sealers based on Capstone® versus competitive silicone was compared. In each test, the sealers were applied to limestone and Saltillo and allowed to dry for 3 days. Then, corn oil, Italian dressing, ketchup, mustard, grape juice, and coffee were placed on the sealed substrates. After 24 hours, the tiles were washed with detergent and scored from 0 to 4 based on the severity of stains remaining, where 0 corresponds with no stain, and 4 corresponds to a heavy stain. The results were then totaled for each tile and sample, and the classification of resistance was characterized.
 

Treatment	Limestone (Total)	Saltillo (Total)	Oil Repellency	Water Repellency	Stain Resistance
Capstone® ST-100HS (8 wt% in water)	6	6	Excellent	Excellent	Excellent
Capstone® ST-110 (10 wt% in water)	3	4
Capstone® ST-200 (4 wt% in solvent)	2	2
Capstone® ST-300 (13 wt% in water)	1	7
Capstone® ST-500 (8 wt% in water)	2	3
Silicone Test #1 (water based)	19	17	Poor	Excellent	Poor to Good
Silicone Test #2 (water based)	8	12
Silicone Test #3 (solvent based)	12	11
Silicone Test #4 (water based)	13	8
Silicone Test #5 (water based)	19	21
Untreated Test #1	16	14	None	None	Very Poor
Untreated Test #2	14	16
Untreated Test #3	13	14
Untreated Test #4	16	14
Untreated Test #5	19	21

From the above data, it’s clear that the penetrating sealers formulated with Capstone® vastly outperformed the silicone-based sealers, with Capstone® exhibiting significantly better repellency for oil-based products. Similar results have been observed using other types of stone, like granite and marble.

Below are two images and the staining pattern used in 24-hour stain tests conducted on Saltillo treated with a sealer using Capstone® ST-110 and untreated Saltillo. This test demonstrates the general stain resistance and excellent repellency Capstone® provides, especially to oil-based products, which show high penetration to untreated surfaces.

Note: Capstone repellents are approved for penetrating sealers used only in indoor applications.