Soft PVC injection moulding: affordable and versatile, but when is it the right choice?

Soft PVC is one of the oldest and most widely used flexible plastics in the world. However, its applications are becoming increasingly limited as sustainability and health requirements become stricter.

What is soft PVC and how does it differ from hard PVC?

In its basic form, PVC (polyvinyl chloride) is a hard, rigid plastic. PVC is made flexible by adding plasticisers, typically phthalates or alternatives such as DINP, DPHP or citrate-based plasticisers. The degree of flexibility can be widely adjusted by varying the plasticiser concentration: from slightly flexible to completely soft and elastic. Soft PVC has been a standard material for cable insulation, hoses, handles and medical disposables for decades. The combination of low cost, flexibility and good chemical resistance makes it a highly versatile material.

Regulations and plasticiser compliance: an area of growing concern

The biggest challenge with soft PVC is not technical but regulatory. Phthalate plasticisers such as DEHP, DBP and BBP have been restricted for years under REACH and RoHS for certain applications. The European Chemicals Agency (ECHA) is steadily expanding these restrictions. Products that come into contact with food, children or skin are subject to particularly stringent standards. Anyone using soft PVC must demonstrate that the plasticiser system employed complies with current European and international regulations.

Applications where soft PVC is still the preferred choice

Despite increasing regulatory pressure and the emergence of alternative materials, soft PVC maintains a strong position in specific market segments. The combination of low raw material costs, excellent flame-retardant properties, a wide range of colour options and proven processability makes it difficult to replace in certain applications.

De Beer Plastics still uses a great deal of soft PVC for a wide variety of applications. One of its specific properties is that soft PVC is highly printable, unlike TPE, for example.

• Cable insulation and sheathing in electrical installations

• Disposable medical products: infusion tubes, blood lines, catheters

• Grips and handles for tools and consumer products

• Sealing profiles and edge finishes

• Toys and promotional items (provided they comply with plasticiser regulations)

When should you switch to TPE alternatives?

The question is not whether TPE alternatives to soft PVC are available — there are plenty of them — but when the switch is technically and economically justified. TPS, TPV and TPU offer comparable or better performance in many applications without the issues associated with plasticisers. The raw material costs of TPE are generally higher than those of soft PVC, but the total cost can be comparable when the additional compliance costs, documentation burden and potential restrictions are taken into account.

Where soft PVC often has the edge over TPE is in terms of wear resistance and printability. With certain types of TPE, particularly TPU, this is also possible, but at a considerably higher cost.

Let De Beer Plastics, a specialist in soft plastic injection moulding, take a look at your project. We know the materials and the possibilities, and can save you a lot of headaches when developing a high-quality product.