Hello! I am a staff member of Hongxiangda.
Often, customers ask us: "How hard should the silicone be for this product?"
This question may seem simple, but it actually directly relates to the product's feel, durability, and performance. Choosing the wrong hardness can result in either an incorrect feel, or worse, product deformation, cracking, or even functional failure.
Today, we will clarify this matter about silicone hardness.
What is silicone hardness?
Silicone hardness, simply put, is the material's ability to resist external force pressing into its surface, which is what we feel when we touch it with our hands - whether it is soft or hard.
In the industry, there are strict standards for measuring hardness - the Shore Hardness (Shore Hardness). Silicone is an elastic material and is usually measured using the Shore A (Shore A) scale. The numerical range is from 0 to 100, with higher numbers indicating greater hardness and lower numbers indicating softer materials.
The hardness range of regular silicone products is generally between Shore A 10 degrees and 80 degrees. Silicone with a hardness lower than 10 degrees has low tear strength and is prone to deformation; silicone with a hardness higher than 70 degrees becomes brittle and is prone to cracking.
What products are suitable for different hardness levels?
Having understood the feel, let's now take a look at which common products correspond to different hardness levels:
Super Soft (10-20A) - As soft as skin
Suitable for products that require extreme softness and skin-friendly properties:
Baby pacifier, soothing nipple
Bionic skin, soft tissue model
High-end cake mold
This type of material feels like human skin or QQ candy when touched, and has excellent elasticity. However, its drawback is that it has poor support and is prone to deformation.
Zhongruan (20-40A) - Soft yet resilient
Balanced in softness and support, it is the most versatile:
Most sealing rings and sealing gaskets
Medical face mask, drainage tube
General-purpose mold adhesive
Rubber bands, silicone spoons
This range is regarded as the "optimal state" of silicone performance - with good tear strength and elongation rates.
Medium (40-60A) - Balancing comfort and durability
This is the most commonly used hardness range, which takes into account both the comfortable feel and the structural strength:
Silicone buttons (40-60 degrees)
Smartwatch strap (40-60 degrees)
Mobile phone case (50-70 degrees)
Silicone cookware, spatulas, scrapers (50-70 degrees)
If you're not sure about the hardness you want, a temperature range of 50-55 degrees is usually the safest "all-purpose" option.
Harder (60-80A) - High support, high wear resistance
Scenarios requiring structural support and wear resistance:
Industrial rollers, gears
Industrial parts requiring high supporting force
High-hardness sealing components
This type of hard silicone has good wear resistance and strong tear resistance, but its elasticity decreases and the feel becomes a bit hard.
What can Hongxiangda do for you?
At Hongxiangda, we have accumulated rich experience in hardness adjustment over the past 15 years. From ultra-soft silicone at 10 degrees to hard silicone at 80 degrees, we can handle all of them.
When you are unsure about the desired hardness, we will:
Based on the intended use and application scenarios of your product, we recommend an appropriate hardness range.
Provide samples of different hardness for you to compare and experience.
During the proofing stage, repeatedly verify to ensure that the hardness meets your expectations.
There is no "standard answer" for silicone hardness. It depends on your product and the usage scenario. Choosing the right one is crucial for the product to perform at its best.
If you are developing silicone products and unsure about the hardness, please come to Hongxianda to have a chat. We will help you find the "just-right" solution.