Food contact
Pacifiers, teats & feeding parts
Food-contact LSR grades with supplier documentation for FDA 21 CFR 177.2600 and LFGB. Finished parts are tested to your target standard, such as EN 1400 for pacifiers, at the accredited lab you choose.
Liquid silicone rubber · Dongguan, China
LSR injection molding for skin-safe electronics.
We mold liquid silicone around circuit boards, motors and heaters, sealing them into one seamless, waterproof, soft-touch body. We handle the tooling, molding, finishing and assembly in our ISO 13485-certified factory in Dongguan, for brands in the US and Europe.
- LSR injection presses
- 4
- Max clamping force
- 200 t
- Shore hardness range
- 0–50A
- Sealed encapsulation
- IP67
No seams. No glue. Nothing to leak.
Products that are held against skin, washed daily and used around babies need a body with no gaps. Here is how liquid silicone injection compares with the alternatives brands usually weigh up.
| Criterion | LSR injectionLeutoo core process | Compression-molded siliconeHCR / solid silicone | Plastic shell + sleeveABS / PC housing |
|---|---|---|---|
| Seams & glue lines | None. One continuous silicone skin | Parting line with secondary trimming | Visible joints; glued, clipped or welded |
| Waterproofing | IP67 through full encapsulation | Depends on how parts are assembled | Relies on gaskets or ultrasonic welds |
| Consistency at volume | Metered dosing, repeatable automated cycles | Hand-loaded preforms, more part-to-part variation | Shell is consistent; sleeve fit varies |
| Feel against skin | Soft-touch, seamless, Shore 0–50A | Soft, but with more visible flash | Hard edges where materials meet |
| Tooling investment | Higher | Lower | Medium (two or more tools) |
| Best for | Skin-contact electronics from 2,000 pcs | Simple parts, prototypes, low volume | Rigid devices that do not need softness |
From liquid to finished product, in-house.
No subcontracted molding and no outsourced assembly. Every stage below runs on our own floors in Building 17, so one team answers for your part from the first shot to the carton.
- 01
Mold design & DFM
Our engineers design the tool around LSR’s low viscosity: venting, gating, shut-offs and wall thickness, so the part fills fully without flash. You get a DFM report before any steel is cut.
- 02
Dosing & mixing
Two-part platinum-cure silicone (A + B) is metered 1:1 with pigment by an automated dosing unit, then mixed inline. That keeps hardness and color consistent from the first shot to the last.
- 03
Injection & cure
Silicone is injected into the heated mold on one of our 4 vertical LSR presses (up to 200 t clamping force). Vertical clamping lets us place PCBs, motors and heaters as inserts and seal them in one shot.
- 04
Deflash, grind & polish
Parts are trimmed, tumble-ground and hand-polished at dedicated stations. Parting lines and gate marks are finished to the approved golden sample.
- 05
Cleanse & oil-spray coat
Washed parts pass through automated oil-spray booths and a tunnel curing line. This gives the silky, dust-resistant finish buyers notice the moment they pick the product up.
- 06
Assembly & encapsulation
Electronics are soldered, tested and assembled on the cleanroom line, then fully or semi-encapsulated. Laser marking adds your logo and regulatory text.
- 07
Test & release
Every lot goes through IQC, in-process and final inspection, with IP67 waterproof, button-life, motor and drop tests in our reliability lab before it is released to packing.
The numbers buyers ask for first.
Send this table to your sourcing team, or ask us for the full equipment list and a live video tour of the molding floor.
- LSR presses
- 4 vertical liquid silicone injection molding machines
- Clamping force
- Up to 200 tons
- Other processes
- Compression molding for low-volume and simple parts
- Material
- Two-part platinum-cure LSR; food-contact and skin-contact grades
- Hardness
- Shore 0–50A
- Encapsulation
- Full or semi-encapsulation of PCB, motor, heater and battery
- Ingress
- IP67 waterproof, verified with in-line waterproof testing
- Acoustics
- Motor noise ≤ 45 dB
- Finish
- Matte, silky oil-spray coating, polished or textured
- Marking
- Laser marking of logos and regulatory text
- Color
- Pantone-matched, color-fastness tested
- Tooling lead time
- 25–30 business days to T1 samples
- MOQ
- 2,000 pcs
- Factory capacity
- 5M units per year
The right silicone grade for the market you sell into.
We choose the LSR grade with you before tooling starts, based on what the product touches and where it will be sold, and we keep batch records so every lot can be traced back to its material.
Skin contact
Massagers, wearables & trainers
Skin-contact grades with biocompatibility data (ISO 10993 series) for products worn or held against the body. Complete products are tested for REACH, RoHS and California Prop 65.
Medical devices
Built inside ISO 13485
Our ISO 13485:2016 certificate (SGS UK, CN25/00005740) covers the manufacture of medical breast massagers, with documented validation, risk control and traceability for medical-device buyers.
Download certificateYour mold. Your design. Your terms.
NNN
Signed before drawings
A non-disclosure, non-use and non-circumvention agreement protects your design from the first email.
100%
Tooling ownership
On custom projects the molds can be yours outright, confirmed in writing and used only for your orders.
25–30
Business days to T1
From design freeze to first-shot samples in your color and texture.
2,000
Pieces MOQ
For custom LSR products and private-label orders on our platforms.
What we mold in LSR every day.
Our four mother & baby product lines all start on the LSR floor. Custom skin-contact parts can be molded to your drawings too.
07 / Buyer questions
LSR questions, answered.
Can't find what you need? Email elvis@leutoo.com and an engineer will reply within one working day.
Q01 What is LSR injection molding?
Liquid silicone rubber (LSR) injection molding meters a two-part, platinum-cure silicone, mixes it, and injects it into a heated mold where it cures in a short, repeatable cycle. It produces consistent, low-flash parts, and it is the best way to seal electronics inside a seamless, skin-safe silicone body.
Q02 What is the difference between LSR and compression-molded silicone?
LSR is automated, more consistent and better for encapsulating electronics or making complex shapes at volume. Compression molding with solid (HCR) silicone has lower tooling costs and suits simple parts or low volumes. We run both processes and recommend the one that fits your part and budget.
Q03 How many LSR machines do you have, and what clamping force?
We run 4 vertical LSR injection molding machines with clamping force of up to 200 tons. We support them with compression molding, tunnel curing, oil-spray coating and a full assembly line.
Q04 Can you encapsulate electronics in silicone?
Yes. Most of our products seal a PCB, motor, heating element and battery inside liquid silicone, either fully encapsulated or as a semi-encapsulated shell. Sealed designs reach IP67 and are tested for waterproofing, buttons, motors and drops before release.
Q05 How long does LSR tooling take, and who owns the mold?
New LSR tooling takes 25–30 business days to T1 samples. On custom projects you can own the tooling outright, and we sign an NNN agreement before receiving your drawings.
Q06 What is your MOQ for LSR molded products?
Our minimum order quantity is 2,000 pcs, for private-label products on our existing platforms and for custom LSR projects alike.
Q07 What hardness and colors can you mold?
We mold from Shore 0A (very soft, skin-like) to 50A (firm, structural), with Pantone-matched colors checked for color-fastness. Finishes include matte, silky oil-spray coating, polished and textured surfaces.
08 / Request for quotation
Tell us what you're building.
An engineer, not a sales script, replies within one working day with questions, a feasibility view and next steps. Tick the NNN box and we'll send our signed NNN agreement before you share drawings.
- Emailelvis@leutoo.com
- Phone+86 158 1584 0058
- WhatsAppMessage us
RFQ received
Thank you. Your brief is with our engineering team.
We've emailed you a copy. Expect a reply from a Leutoo engineer within one working day (China time, GMT+8).