Capstone™ ST-500
Repellent

Penetrating Sealer for Porous Surfaces
Technical Information
Description

Typical Properties

Capstone ST-500 is an anionic aqueous fluorochemicalsolution with no intentionally-added VOC that provides adurable, non-film forming, transparent protective barrier
against oil and water on porous mineral surfaces. Capstone™ ST-500 is a repellent used in water-based penetrating sealers for stone, unglazed tile, grout, terra cotta,
concrete, granite, and brick. Capstone™ ST-500 provides
oil and water repellency, stain resistance, and easy staincleanup.

Appearance™

Applications and Formulating Information
Capstone™ ST-500 is used in diluted solutions containing
1.5–2.5% active ingredient (6–10% commercial product)
working strength with deionized or soft water (<50 ppmhardness). Typical coverage rate is from 3–25 m²/L of
diluted solution, depending on the porosity of the mineralsubstrate. Thoroughly wet the surface being treatedwith the diluted product, and remove excess liquid
after 15–30 min. The optimum dilution rate should bedetermined for each application. If blended, maintainpH >7.
This product is anionic and is usually compatible withother materials in a blended system (except cationicadditives). It is recommended that the blended system
be checked for stability. For dense substrates, optimum
performance can be achieved with the addition of 2–5%
polar, protic solvents, such as isopropyl alcohol or glycol
ether. The product may be applied using a saturated
brush, roller, paint pad or mop in one or two layers (to ensure complete coverage). A biocide should be added toformulations made using Capstone™ ST-500 to protect
the formulation against microbial growth.

Clear, pale yellow liquid to Amber liquid

Stability

Stable at normal temperatures
Perishable if frozen

pH

9.0–11.0

Active Solids, %25Density, g/mL

1.1

Flash Point (Closed Cup), °C (°F)

Does not flash

Shelf Life

2 years

Performance
Capstone™ ST-500 (diluted to 8% of commercial productin deionized water) was compared to a competitive
aqueous-based silicone sealer. Each product was applied
to limestone and Saltillo (Mexican clay tile or terracotta) and allowed to dry for three days. Corn oil, Italiandressing, ketchup, mustard, grape juice, and coffee werethen placed on the treated substrates. After 24 hr, thetiles were washed with a 1% soap solution and allowed
to dry. The ratings were totaled for each tile sample. The
results below show that Capstone™ ST-500 outperformed
the competitive aqueous-based silicone sealer. Similar
results have been achieved on other porous mineralsubstrates.

Repellent

Capstone™ ST-500

Personal Safety, First Aid, Storage and Handling

Scoring System for Each Stain After Dry

See the Safety Data Sheet (SDS) for use and handlingrecommendations. Mix well before using. Protect fromfreezing.

No Visible Stain0

Very Slight Stain

1

Light Stain

2

Moderate Stain

3

Capstone™ Repellents and Surfactants

Heavy Stain/Complete Penetration of Stain into Substrate

4• Deliver maximum performance• Regulatory and stewardship information is available
upon request

Scoring System for Water/Oil Repellency• Are listed on TSCA inventory
Package Sizes

5—Excellent

4—Very Good

3—Good2—Fair

1—Poor0—Penetration

5 Contact angle 100–120°

4 Contact angle 75–90°

3 Contact angle 45–75°

2 Contact angle 25–45°

1 Contact angle 10–25°

0 Contact angle <10°Tote–2,205 lb (1000 kg), Drum–440 lb (200 kg),
Pail–44 lb (20 kg)
For questions regarding technical data, commercial
supply, and sampling:
Chemours Advanced Performance Materials
Technical Inquiries

Performance Comparison
24 hr Stain Scores of Six Stains
Treatment

Limestone

Saltillo

Capstone™ ST-500

23

Silicone (aqueous)

813

Untreated

1921

Oil Repellency

Water
Repellency

Stain
Resistance

Capstone™ ST-500

Excellent

Excellent

Excellent

Silicone (aqueous)

Poor

Excellent

Poor to Good

Untreated

None

None

Very Poor

Cumulative scale from 0 (best) to 24 (worst).
Lower score = Higher performance

Treatment

Asia PacificEurope
Latin America
North America+86.400.671.6789+41.22.719.1537+55.08.0011.0728+1.866.828.7009

Regional Technical Customer Service Center, Americas
The Chemours CompanyChemours Discovery Hub
201 Discovery Boulevard
Newark, DE 19713 USA+1.866.828.7009

For more information, visit www.chemours.com/capstone
CAUTION: Do not use or resell Chemours™ materials in medical applications involving implantation in the human body or contact with internal body fluids or tissues unless agreed to by Seller in a writtenagreement covering such use. For further information, please contact your Chemours representative. For medical emergencies, spills, or other critical situations, call (866) 595-1473 within theUnited States. For those outside of the United States, call (302) 773-2000.
The information set forth herein is furnished free of charge and based on technical data that Chemours believes to be reliable. It is intended for use by persons having technical skill, at their own discretion
and risk. The handling precaution information contained herein is given with the understanding that those using it will satisfy themselves that their particular conditions of use present no health or safety
hazards. Because conditions of product use are outside our control, Chemours makes no warranties, express or implied, and assumes no liability in connection with any use of this information. As with anymaterial, evaluation of any compound under end-use conditions prior to specification is essential. Nothing herein is to be taken as a license to operate under or a recommendation to infringe any patents.
NO PART OF THIS MATERIAL MAY BE REPRODUCED, STORED IN A RETRIEVAL SYSTEM OR TRANSMITTED IN ANY FORM OR BY ANY MEANS ELECTRONIC, MECHANICAL, PHOTOCOPYING, RECORDING OR OTHERWISEWITHOUT THE PRIOR WRITTEN PERMISSION OF CHEMOURS.

© 2022 The Chemours Company FC, LLC. Capstone™ is a trademark of The Chemours Company FC, LLC. Chemours™ and the Chemours Logo are trademarks of The Chemours Company.
Replaces: K-25186-4
C-11343 (7/22)