Solution For Sink Mark, Warping In TPE Overmoulding

Most styrene series TPE have a high molded shrinkage that causes the laminated composite to contract more than the substrate (typically PP,ABS,PC,PA, etc.), resulting in bending or warping of the substrate parts. This is especially true for long, thin parts, or parts with a substrate thickness thinner than the coating, or for substrate materials with a lower modulus of elasticity.

This situation can be handled in the following ways:

Selection of TPE materials:

  1. Adopt matrix materials with higher elastic modulus.
  1. Add reinforcing rib to matrix parts.
  1. Minimize the thickness of soft TPE layer.
  1. Use TPE materials with lower hardness.
  1. Change the gate position to minimize the proportion of flow length to thickness
  1. Change the mold. In some cases, due to mold problems, resulting in: product deformation, difficult to demoulding.

Of the above five solutions, the second and fifth solutions are practical and operable, but need to adjust the mold structure; For the remaining solutions 1, 3 and 4, due to limited material and product requirements, there is not much space for actual adjustment.

Adjustment from TPE mixture formula can reduce the cooling shrinkage force of TPE to a certain extent, thereby reducing the shrinkage warpage of TPE overmoulding. This is also from the point of view of adjusting the physical properties of the raw materials to improve the shrinkage warp defect of overmoulding, relatively speaking, this is one of the most easy to implement TPE overmoulding solution.

About JasonMould Industrial Company Limited

Jasonmould is a China mold maker of plastic molds- injection mold, die casting moulds, plastic blow molding, rotational molding, medical plastic injection molding, two shot plastic injection molding, insert molding, overmolding, metal injection molding, micro injection molding, powder injection molding, ceramic injection molding, liquid injection molding, husky injection molding, household mold, casting mold, die mold tool, custom molds, china moulds, rapid prototyping tooling, plastic prototyping tooling, punch press tooling, die and tooling for mobile/ cell phone parts, automotive parts, vacuum cleaners, rechargeable tools, telephones, copiers, computers, multimedia speakers, and many other electronic products and household appliances. And also a plastic product manufacturer, mold manufacturer China– plastic parts, plastic water tank, plastic balls, plastic containers, plastic buckle, plastic anchor, plastic hanger, plastic spoon, plastic pipe fitting, plastic tumble, plastic tableware, plastic cups, plastic bottles, plastic tray, plastic cosmetic container, plastic case, plastic food container, plastic chairs, plastic caps, plastic cap closure, plastic tubes, plastic water pipes, plastic knobs, plastic tubing, plastic utility boxes, plastic racks and so on.

Person: James Yuan
Company: JasonMould Industrial Company Limited
Add:  LongGang Village,LongXi Town,BoLuo County,HuiZhou City,GuangDong Province, China
Tel: 86-752-6682869
Email: [email protected]