Technomelt Moulding Materials
Frequently asked questions about Technomelt low pressure moulding materials
What is the typical viscosity of the material?
Technomelt moulding materials typically have a viscosity range of 2500-5000 cP at 210°C (410°F).
Do dyes and pigments added for color change the material properties?
Generally, there isn’t a dramatic change in properties (i.e. black versions of the products are similar to amber). The pigment is extruded into the amber Macromelt material. However, any colored material, which requires opacity (i.e. white), would need a significant quantity of inorganic filler, which will affect most of the properties.
What is the typical shrinkage of the materials?
Shrinkage varies during injection and can usually be controlled by packing the mould with pressure. The shrinkage rate 24 hours after injection is 1 to 1.5%, depending on the grade of material.
How are the materials packaged?
Should they be dried prior to use? Materials are shipped in double walled 20 kg (44 lbs.) bags. The materials are nylon-like and will absorb some moisture from the air. The materials are shipped at the recommended level of 0.2% moisture and should be kept in an air-tight container after the bag has been opened.
What is the delivery time for materials?
The Technomelt® OM product line is manufactured in Europe and warehoused in the UK. Henkel generally keeps about 2 tons of each material above forecasted volumes. Drop shipments from Henkel or Overmould customers usually take 5 business days form the point the order is made with Henkel customer service. Other Macromelt® materials (used for moulding) are also readily available.
Who will provide technical support for the materials?
Henkel will supply material support. Application engineering and support such as prototypes and the development of moulding parameters will be supplied by Overmould Ltd.
How do Technomelt® materials compare to engineered resins economically?
Technomelt® rarely replaces traditional plastic materials directly. If a component can be moulded successfully with PVC, there is no reason to consider Technomelt®. If PVC moulding results in high scrap levels as a result of high injection pressure, Low-Pressure Moulding may be more economical as a result of reduced scrap. Typically, the Low- Pressure Moulding operation is an alternative to potting as it replaces several manufacturing operations. Over-moulding with Technomelt® is typically a single step process. When a component is over-moulded with Technomelt® there is normally no need for a separate plastic housing. The over-moulding material becomes the housing.
Can material regrind be used?
For applications where adhesive properties are critical, regrind should not be used. The regrind material will contain a small amount of mould release agent, which could compromise adhesive properties. Furthermore, the mechanical properties of the material will degrade some from repeated re-melting. For non-critical applications the runners can simply be thrown back into the melt reservoir without any regrinding. It is strongly recommended to confirm that components moulded from “regrind” material meet specifications.
What is the minimum tolerance that the Technomelt®‚ materials can hold?
Tolerances of 0.1mm (+/- 0.004”) can be met on smaller components.
What is Technomelt®?
Technomelt® is group of high performance polyamide adhesives. They are essentially reformulated hot melts with strong adhesive properties designed specifically for insert moulding of electronics. Technomelt® is a thermoplastic material that cures simply by cooling. It does not cross-link nor does it release any toxic fumes.