Which release agent types have what benefits and drawbacks?

Each type of agent has distinct strengths (S) and limitations (L). Here is a quick breakdown by release agent type:

Solvent-based release agents:

S: Simpler to use. The solvent carrier aids in the development of the film. Depending on the mixture of the solvents, the evaporation rate can be changed. The active components in the release agent may dissolve or disperse more easily depending on the solvent used.

L: Not particularly eco-friendly. Bring more safety and health risks (fire dangers) compared with non-solvent based solutions.

Water-based release agents:

S: Non-flammable and beneficial to the environment. Can sometimes be shipped in concentrates and may be possible to dilute. If necessary, they can be employed to chill the die. Might also be created with technology that guarantees mould release agents operate on par with solvent-based release agents.

L: Require more sophisticated manufacturing technology. The correct formation of films can be more difficult. This group of release agents might be more vulnerable to deterioration and biological attack. Water-based release agents may not be suitable for all room temperature moulding processes or operations with short cycle periods since they evaporate more slowly than their solvent-based counterparts. Entrapped steam or even chemical reactions with the material being moulded could be caused by residual water on the mould. The latter is especially problematic when moulding polyurethane components.

Carrier-free Release Agents:

S: Due to the lack of a carrier, it can be used “as is”. No vapours are released. Application noise is reduced. Doesn’t need tank storage or dilution. Zero waste stream.

L: If improperly applied, can pose a dust danger. Necessitate the use of specialised application equipment, frequently electrostatic spray guns, which could be expensive to purchase. To guarantee that the mould is thermally balanced while using carrier-free release agents, extra adjustments to the moulding apparatus may be necessary. These factors frequently restrict the use of this group of release agents.

Sacrificial Release Agents:

S: Simple to use. Lessen the requirement for application technique and increase work tolerance (reducing reliance on qualified workers).

L: If applied excessively, tends to build up on the mould. The release coating generally transfers in part to the moulded part, which could have adverse effects on subsequent post-moulding processes (painting, adhesion, etc.) if applied excessively or if the chemistry of the release agent is incompatible with the process. If water-based, they have a tendency to cool the mould, taking heat and energy out of the system (this could be a drawback if the process is bot set up accordingly).

Semi-Permanent Release Agents:

S: Because the release agent film lasts for several moulding cycles, they require substantially less frequent application than sacrificial release agents (the frequency is dependent on the process parameters). Enables release agent application to be done in a more continuous, constant manner. It is possible to do ehanced post-moulding operations (coating, adhesion) since there is very little transfer to the moulded object. On the coated mould, the release agent can be reapplied frequently to renew the release agent film. In order to prevent build-up and give the desired release performance, this category of release agents offers a very good combination of chemical and physical barriers.

L: Operators must receive further training to guarantee that the proper touch-up frequency is followed. For the initial application of the release agent to work well and effectively with the mould surface, the moulds must be clean.

Internal Mould Release Agents:

S: Reduce the use of outside mould release agents.

L: Over time, it may continue to move out to the surface, endangering the part’s surface aesthetics or post-moulding operations (coating and adhesion). As internal mould release agents may not always migrate to the mould interface or may not guarantee a 100% release efficiency, they frequently do not completely eliminate the necessity for external mould release agents. They are constrained in their capacity to carry out high performance release agent functions, such as changing the part surface properties.