Quartz countertops have become incredibly popular in kitchen and bathroom remodeling projects thanks to their durability, low maintenance, and wide variety of colors and patterns. But what exactly is quartz made of, and what resin binds it all together into those beautiful countertops we love? Let’s take a closer look at the makeup of quartz and the resin used in quartz countertops.
What is Quartz?
Quartz is a naturally occurring mineral composed of silicon and oxygen atoms. It is one of the hardest minerals found in nature and is valued for its durability and resistance to both chemicals and heat. Natural quartz crystals are transparent to translucent and come in a variety of colors.
For countertops, quartz is ground into a fine powder and then combined with materials like resins and pigments to create an engineered stone. The main quartz material used in countertops is derived from quartzite, a metamorphic rock made almost entirely of interlocking quartz grains.
The Role of Resin
Resin acts as the glue that binds together the crushed quartz crystals and other materials to create a durable, non-porous countertop. The most common resin used in quartz countertops is unsaturated polyester resin. This thermosetting resin starts as a liquid but then hardens permanently once exposed to heat and pressure.
Unsaturated polyester resin has numerous properties that make it well-suited for its role in quartz countertops:
- Binding ability – The liquid resin is able to coat and bind all the quartz particles together.
- Hardness – The cured resin is very hard and durable, allowing it to withstand daily wear and tear.
- Stain resistance – The resin does not absorb stains like a natural stone.
- Workability – The liquid resin allows the countertop material to be cast into customized shapes and sizes.
- Weather resistance – The cured resin resists damage from UV exposure and humidity.
- Affordability – Unsaturated polyester resins are relatively inexpensive compared to other resin options.
Quartz Countertop Manufacturing Process
During manufacturing, the unsaturated polyester resin plays a crucial role in transforming crushed quartz into a countertop slab. Here is a basic overview of the manufacturing process:
- Quartz crystals are mined, crushed, cleaned, and ground into a fine powder.
- The quartz powder is combined with unsaturated polyester resin and pigments for color.
- The mixture is compacted into a slab mold and cured in a high-pressure vacuum environment.
- The heat and pressure cause the resin to harden, binding the quartz particles into a solid slab.
- The finished slab is polished, cut to size, and prepared for installation.
Pros and Cons of Polyester Resin Countertops
Using unsaturated polyester resin offers several benefits for quartz countertops:
Pros:
- Excellent durability and scratch resistance
- Stain and water resistant
- Resists heat damage
- Non-porous surface inhibits bacteria growth
- Flexible formulation options
- Cost-effective compared to other resins
Cons:
- Not as heat, chemical, and scratch resistant as epoxy resins
- Surface can gradually lose gloss over time
- Seams may be more visible than with other resins
- Resin odors may linger after installation
While not perfect, unsaturated polyester resin provides an optimal balance of performance and affordability for quartz countertops. Advancements in resin technology continue to improve the qualities of quartz surfaces.
Popular Brands of Quartz Countertops
Many leading manufacturers of engineered stone use unsaturated polyester resin for their quartz countertops. Some of the most popular quartz countertop brands include:
- Caesarstone – One of the pioneers of quartz surfaces, known for quality and variety.
- Cambria – Features elegant designs and durable Breton quartz technology.
- Silestone – Offers a diverse collection of over 90 quartz colors and textures.
- LG Viatera – Combines delicate styling with resilient construction.
- Quartz Master – Focuses on affordable luxury quartz countertops.
- HanStone – Provides high-performance quartz for heavy use kitchens.
Caring for Quartz Resin Countertops
The durable resin binder allows quartz countertops to stand up well to regular use. However, proper care is still required to keep them looking like new:
- Clean with mild soap and water. Avoid abrasive cleaners.
- Disinfect surfaces periodically with diluted bleach.
- Rinse with water after using cleaning products. Acids can damage resin.
- Avoid exposing counters to very high temperatures. Use trivets for hot pans.
- Reseal countertops every 1-2 years to replenish gloss and protection.
- Handle spills quickly to prevent stains from setting.
With proper care, a quartz resin countertop can stay in great shape for many years of heavy kitchen use. The durability and stain resistance provided by polyester resin makes quartz an extremely popular choice.
Frequently Asked Questions
What percentage of quartz is in a quartz countertop?
Typical quartz countertops contain between 90-95% ground quartz combined with 5-10% polymer resins. Higher quartz content increases strength and hardness.
Is unsaturated polyester resin safe?
Yes, once fully cured and hardened, unsaturated polyester resin is considered non-toxic and food-safe. It does not release chemicals under normal use. Proper ventilation is needed when working with the liquid resin.
How thick should a quartz countertop be?
A thickness of 2 cm (3/4″) is the minimum recommended, while 3 cm (1 1/4″) provides optimal strength and durability for heavily used kitchen countertops. Thicker quartz is less prone to cracks or damage.
Can you repair chips in a quartz resin countertop?
Minor chips and scratches can be sanded and polished out of a quartz countertop. However, deep cracks or damage requires replacement of the affected area. The resin binder makes full repairs very difficult.
Are there sustainable options for quartz resin?
Some manufacturers are exploring bio-based resins made from plant oils. Recycled glass and non-mining quartz alternatives also provide greener options. However, polyester resin remains the most common binder today.
Conclusion
Unsaturated polyester resin plays a crucial role in quartz countertops. This thermosetting plastic binds together crushed quartz powder into durable, customizable slabs. The cured resin provides ideal hardness, weather and stain resistance, and workability. While not without some drawbacks, polyester resin allows quartz countertops to offer homeowners an attractive, low-maintenance, and long-lasting surface for kitchens and baths. Proper care helps maximize the longevity of quartz countertops fabricated using unsaturated polyester resins.