Silicone

Silicone belongs to the silicone elastomer contact material group, supplied as silicone bristle or body, drawn in round, tapered, rectangular, star and sheet sections and set in straight rows, staggered, zoned, wavy and random fill patterns.

Silicone is used in custom cleaning brushes for molded soft-contact fins, bottle heads and wiping tools that benefit from easy cleaning and elastic recovery.

The realistic alternatives are Polypropylene PP, TPEE Elastomer Filament and Nylon PA. What separates them here is moisture uptake and working temperature, not headline strength.

Compare Silicone with PP, TPE, Nylon. Change material when wet stiffness, temperature, chemical resistance, conductivity, particle shedding, or surface marking becomes the limiting factor.

Silicone is soft to medium elastomer; Shore A commonly about 30-80 depending grade, which is why Silicone changes brush stiffness through filament diameter, free trim, density, crimp, and contact. Use finer filament and longer trim for conformable contact; use coarser filament, shorter trim, or higher density for stronger displacement or cutting.

Published ranges for the filament itself. Read them as a shortlist tool, not as brush performance.

The part people get wrong: stiffness is not a property of the material on its own. A 0.50 mm filament on a 15 mm trim is stiffer than a 0.30 mm filament on a 25 mm trim in the same grade. Fix diameter and trim first, then confirm the material.

Silicone takes up 0.1–1.0% (Grade/Formulation Dependent, ISO 62/ASTM D570).

Non-absorbent elastic contact for wet cleaning, wiping and squeegee action.

What this means for your application: it barely absorbs water, so dry and wet contact pressure are effectively the same and the brush behaves alike on both duties.

A practical check: soak a sample for an hour and re-measure the trim. If it has moved enough to change the contact band, the grade is wrong for the duty.

-50 to 200°C.

Design to that answer rather than to a raw-material datasheet figure: a brush rating already accounts for filament working under load rather than raw polymer sitting in an oven.

Where it stops working: validate with a sample if the process sits near the top of that band. A permanent bend under load means the answer is a higher-temperature filament family, not a heavier trim.

The usable limit also moves with diameter, trim and contact pressure. A fine filament under light load tolerates more than a thick one under heavy scrubbing.

It stands up to water and common detergents.

The same cleaner can be harmless or destructive depending on how strong it is, how hot it runs and how long it sits. Quote the concentration and the dwell time, not just the product name.

Before you commit to a quantity: Specify the exact Silicone grade or alloy, filament or profile size, color, straight or crimped form, working temperature, wet or dry use, chemical exposure, surface finish, and any required material documentation.

About 0.30 mm. Below that the filament turns fragile and breaks under ordinary contact pressure, so 0.30–5.00 mm is the working range.

Free trim runs 2–100 mm, and the two interact: a finer filament needs a shorter trim to keep useful stiffness, while a thicker one carries a longer trim and still lands pressure on the tip.

Split the range by duty: roughly 0.30–1.48 mm for light wiping, dusting and surfaces that mark easily, and 1.48–5.00 mm where residue is packed on and point pressure matters more than surface risk.

Tip treatments available on this filament: plasma treatment, silicone-oil coating, anti-static coating and antibacterial formulation.

In practical brush terms: reaching deep into a bore or crevice is a diameter problem before it is a length problem. A thicker filament on a moderate trim pushes further in before the tips fold over.

Molded soft-contact fins, bottle heads and wiping tools that benefit from easy cleaning and elastic recovery.

The applications that keep coming back to this grade:

• Bottle & Container Cleaning
• Cup & Mug Cleaning
• Hydration Bag Cleaning
• Laboratory Tube Cleaning
• Beverage Equipment Cleaning
• Hose Cleaning

The constructions that usually carry it:

• Custom Handheld Detail Brushes
• Custom Tube & Pipe Bore Brushes
• Custom Bottle & Container Brushes
• Custom Disc Brushes

If the sample comes back rejected: Not for aggressive scraping, rust removal or metal deburring.

A usable specification carries the construction, the filament diameter and free trim, the density and contact setting, and the service conditions: wet or dry, temperature, and what the cleaner actually is.

The mistakes that most often send a sample back:

• Selecting Silicone from the material name alone without setting filament diameter, trim length, and density
• Using dry stiffness to predict wet behavior without checking moisture absorption or liquid exposure
• Ignoring trapped abrasive particles, chemical concentration, temperature, or contact motion when assessing surface risk

Reference standards behind the figures on this page: ISO 37; ASTM D412; ISO 48-4; ASTM D2240-15(2021); ISO 4892-3:2024; ASTM G154-23; UL 94.

Source: Dow — Silicone elastomers — LSR product technology. Silicone is chosen for temperature range, cleanliness and low taint rather than for wear life. Confirm the grade where the part meets food, since not every silicone compound is qualified for it.