Common Names: Waterglass, Soluble Glass 
Function: pH stabilizer, corrosion inhibitor, detergent builder 
EWG Rating: 2 (Low Concern) 

What It Is

Sodium silicate is an inorganic salt composed of sodium, silicon, and oxygen. It forms a clear, water-soluble solution that is alkaline in nature. It has wide industrial use and is commonly found in cleaning products, where it functions to stabilize pH and enhance cleaning performance.

What It Does in Laundry

In laundry detergents, sodium silicate performs several supporting functions:

1. pH buffering: Helps maintain an alkaline environment during the wash cycle to improve the effectiveness of surfactants and enzymes.
2. Corrosion inhibition: Protects washing machine components (especially metal parts) from scale and corrosion.
3. Soil suspension: Assists in preventing loosened dirt and soils from redepositing on fabrics.

It is not a primary cleaning agent but plays a critical behind-the-scenes role in maintaining system stability and cleaning performance.

Safety and Environmental Profile

• Biodegradability: Inorganic; does not biodegrade but breaks down into naturally occurring components.
• Human safety: Considered safe in diluted form. May be an irritant in concentrated solutions but is not classified as toxic.
• Environmental impact: Low. Does not bioaccumulate or persist in aquatic systems in detergent use concentrations.

Source and Production

Sodium silicate is produced by combining silica (sand) with sodium carbonate (soda ash) at high temperatures in a furnace. This process yields a glassy, water-soluble material that can be cooled into solid form or dissolved into liquid silicate, depending on the application.

The production relies on abundant, naturally occurring mineral inputs and does not involve petrochemicals or hazardous solvents. It generates minimal waste byproducts, and the resulting compound is chemically stable, shelf-safe, and environmentally durable. Due to its inorganic composition and inert nature, sodium silicate is widely accepted as a safe and efficient ingredient across personal care, and cleaning sectors.

This profile is part of Orchard’s Ingredient Glossary, written to provide information on every component we use.