Hormone Ring

Hormone rings made from LSR can be used by women for HIV prevention. The most stringent requirements with regard to hygiene and product quality must be met during production. The special advantage: before injection moulding, an agent is mixed into the liquid silicone, which provides protection against HIV.

A production cell built around an ALLROUNDER 520 A produces the LSR vaginal rings in large unit volumes. As the main contractor, ARBURG bears the complete responsibility. The clean-room application was developed in cooperation with ARBURG partners Rico and 2KM.


  • High-volume medical production: production cell precisely configured for clean room application
  • Electric injection moulding machine in stainless steel version meets highest hygiene standards
  • LSR implants for the timed release of a pharmaceutical agent to prevent HIV infection
  • Component tolerances of only 0.1 mm


Basic specifications

Hormone ring
Cavities: 16
Part weight: 8 g
Material: LSR
Agent: 25 mg dapivirine (HIV prevention)


A precisely operating electric ALLROUNDER 520 A in a stainless steel version is ideally suited for clean room production. Closed spindle drives as well as liquid-cooled motors and control cabinets contribute towards low-emission production.
to the electric machines

Robotic system
Part handling is performed by a six-axis robotic system adapted for clean room operation, implemented with the SELOGICA user interface. Because the robotic system and machine are directly connected via SELOGICA, their movements can be optimally synchronised.
to the robotic system


Liquid silicone injection moulding (LSR)
The agent is homogenously and finely dissolved in the platinum-vulcanising two-component LSR matrix. The PFM dosage system operates to an accuracy of 0.001 mm. The cross-linking time is 1 - 2 minutes. The primary quality-relevant factor is the correct combination of dosage volume and holding pressure.
to the process

Clean room technology
The electric ALLROUNDER and the entire automation solution are enclosed as a clean room cell with clean air modules, including ionisation. They meet the requirements of clean room class ISO 5. The machine is quick to clean. This results in short downtimes and a high degree of production efficiency.
to the process


Medical technology
Plastics are ideally suited for the medical technology sector. They are unrivalled in terms of cost effectiveness and predestined for injection moulding into virtually any shape and production quantity. The production of hormone rings, for example, requires high precision, high-quality parts and an extremely clean working environment.
to the industry


LSR dosage technology2KM