Release agent – A simple guide
Published date: 18 August 2021
In the following article you can read a bit more about release agents and why they are useful.
What is a release agent?
A release agent (also known as a release coating, or mould release coating) is a chemical that prevents other materials from attaching to surfaces. It can help with mould release, die-cast release, plastic release, adhesive release, and tyre and web release.
They act as a vital barrier between a moulding surface and the substrate, allowing the cured portion to be separated from the mould. Without such a barrier, the substrate would become fused to the mould surface, resulting in laborious clean-up and a significant decrease in manufacturing efficiency.
Even when a release agent is used, variables such as uneven application or incorrect selection can have a significant impact on the completed product’s quality and consistency.
Types of release agents
Cosolvent based
The advantages of a solvent-based system are combined with the safety of water-based release agents in cosolvent-based release agents.
The elimination of health and safety concerns associated with solvent-based release agents, as well as the decrease of volatile organic compound (VOC) levels, were significant motivators in the invention of cosolvent mould release.
Semi permanent
One of the most important characteristics of a releasing agent is its degree of permanence: how long will it last before requiring reapplication.
A semi-permanent release agent does not need to be reapply after each cycle of a moulding operation and performs even better when not over-applied to the mould surface.
Sacrificial
Sacrificial coatings must be placed before each cycle of a moulding operation, making them more labour intensive. Semi-permanent coatings are preferred by most moulders over sacrificial coatings, especially when moulding rubber and plastic parts.
Because they contain less solid elements, these coatings do not persist as long as semi-permanent coatings.
Water based
WBD (water-based die lubricant) has been utilised for almost 40 years. WBD was used in the design of all die casting machines.
Water-based release coatings dry slower than solvent-based ones, but they pose fewer health and safety risks. Because they are intrinsically non-flammable, water-based ones will be less expensive to freight and will meet the majority of plant-safety objectives.
Solvent based
Although solvent-based release coatings dry very immediately, they pose major health and safety problems.
Fumes from solvent-based release agents might be harmful if the work environment is not properly ventilated. The majority of the solvents used in release agents are combustible.
Release agent applications
Asphalt
Asphalt release agents are chemical solutions developed and manufactured as alternatives to diesel and solvents widely used for cleaning equipment related with the production and placement of hot mix asphaltic concrete (HMAC) on government and commercial properties.
Asphalt release agents are intended to eliminate dangerous stripping materials that come into contact with bituminous goods and strip the asphalt (binding agent) from the aggregates, resulting in potholes, ravelling, and other negative pavement failures.
Concrete
Form release agents are used in the concrete construction industry to prevent freshly deposited concrete from adhering to the forming surface, which is typically plywood, layered plywood, steel, or aluminium.
There are two sorts of release agents available in this application: barrier and reactive.
By generating a physical film or barrier between the forming surface and the concrete, barrier release agents prevent adhesion.
Reactive release agents are chemically active and work through a chemical interaction between the release agent and the free limes in fresh concrete. A soapy film is formed, preventing adherence.
Because it is a chemically reactive process, there is little to no residue or unreacted product left on the forming surface or concrete, resulting in a cleaner procedure.
Food processing
After baking or roasting, release agents are used to aid in the separation of food from a cooking container. Traditionally, lard or flour were employed, but additional chemicals may be used in industrial food processing.
The application is referred to as bakery release.
Metal casting
Mold release agent can also be utilised in the die casting or metal forging processes of metals such as aluminium, aluminium alloys, zinc, zinc alloys, magnesium, and so on.
Paper
Release agents are used in industrial papermaking to get the slip effect of the paper from the processing equipment. A releasing agent can be used on the process rolls (such as the yankee dryer) or in the paper coating.
Some types of paper have low surface energy release coatings:
- Liners for release of pressure-sensitive adhesive laminates and tapes
- Papers for casting
- Papers for general industrial release
- Papers for food release and packing
Pharmaceuticals
Release agents (e.g., magnesium stearate) are added to powdered and granulated medication formulations to act as a lubricant during tabletting.
Plastics
Some plastic sheets have release agents sprayed on them to prevent adhesives from attaching to the plastic surface.
Some release agents, also known as de-molding agents, form oils, parting agents, or form releasers, are substances used in moulding and casting to help separate a mould from the material being moulded and decrease flaws in the moulded surface.
ConRo Electronics is an exclusive distributor of Ambersil and all major types of release agents.
We’ll show you how to improve product reliability while increasing performance and lowering costs.
Our team of technical support specialists will provide your company with dependable global supply, unrivaled efficiency, and superior technical support.
For more information feel free to contact us on 0208 953 1211 or send us an email to info@conro.com
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