Publication: Feb 01, 2024 Last updated: Aug 04, 2025

Shrinkage values in accordance with DIN EN ISO 294-4


Shrinkage can be measured for any Shore hardness.

During the industrial processing of plastics, details of their shrinkage values form part of the standard information that is essential as a specification for mold construction. To provide manufacturers with maximally precise data, KRAIBURG TPE has been using a contactless optical measuring device since August 2023, which enables distance measurements required to determine shrinkage values in accordance with DIN EN ISO 294-4.

Waldkraiburg, February 2, 2024 – The measurements “for determining the processing shrinkage and the post-shrinkage of thermoplastics” are based on test specimens 60 x 60 x 2 mm in size that are injection-molded in accordance with the DIN standard, for which the values are determined. During measurements, shrinkages are determined both along the direction of flow and transverse to it.

Combined with other parameters such as wall thicknesses and flow paths, these specifications enable mold makers and calculation engineers to carry out specific calculations for the most accurate dimensioning of their molds. This applies to the manufacture of new molds, but also to adjusting existing molds, e.g. for planned material changes. In all cases, the cavity must be designed in such a way that the material shrinkage, that persists for up to 48 hours after processing, is taken into account in relation to the finished plastic part.

“We previously determined the shrinkage values by using tactile measuring devices,” summarizes Grit Müller of Team Application Engineering at KRAIBURG TPE. “The use of contactless measuring devices has proved to be advantageous, particularly for measuring the shrinkage of soft and very soft materials.” The reason for this, she adds, is that “When using mechanical devices, measurement distortions may occur due to minimal compressive loading, which in turn leads to minimal deviations from the dimensions required for the finished plastic after processing.” According to Grit Müller, the conditions required for using the new optical measuring device – i.e. expanding the in-house test plate production by integrating another insert into the new master die (including internal pressure sensors) – were already established last year.

Since the introduction of the new contactless measuring device, KRAIBURG TPE has been able to determine shrinkage values for all established compounds in accordance with the DIN EN ISO 294-4 standard, irrespective of the Shore hardness of the tested materials. This enables both existing customers and also potential new customers to make decisions on the use of new or alternative materials based on even more precise information. This is of particular relevance for the production of single-component materials, since in these cases it is only the TPE source material that shrinks. But it also makes it possible to better assess the impact on shrinkage in two-component composites.

KRAIBURG TPE Quick Facts
 

  • Founded in 2001 as an independent business unit of the KRAIBURG Group 
  • HQ & Production Site: Waldkraiburg / Germany
  • Regional HQ & Production site: Kuala Lumpur / Malaysia, Atlanta / USA
  • Products: Thermoplastic Elastomer Compounds
  • Brands: THERMOLAST®, COPEC®, HIPEX®, and For Tec E®
  • Markets: EMEA, APAC, Americas
  • Employees: 660

Download press release

In our media package you will find comprehensive information, graphics and pictures on the subject.

01.02.2024 MEDIA PACKAGE FOR Shrinkage values in accordance with DIN EN ISO 294-4

Latest News

Unlocking Advanced Functionality for Smart Locks with Light Effect TPE
09.09.2025 Unlocking Advanced Functionality for Smart Locks with Light Effect TPE How can smart locks, automotive interiors, and consumer electronics combine performance with style? With KRAIBURG TPE’s Light Effect TPE—durable, flexible, soft-touch, and light-transmissible for intuitive illuminated features. read more
Smart TPE Solutions for Tough, Sustainable Toolbox Handles
02.09.2025 Smart TPE Solutions for Tough, Sustainable Toolbox Handles KRAIBURG TPE’s THERMOLAST® R - RC/AD/PA/AP series offers a high-performance TPE material ideal for toolbox handles and power tools. With strong adhesion to PA6/PA6.6, excellent grip, and over 50% recycled content, this sustainable TPE delivers both toughness and comfort. read more
Soft-Touch, Durable & Sustainable TPE for Electric Shavers
20.08.2025 Soft-Touch, Durable & Sustainable TPE for Electric Shavers THERMOLAST® R sustainable TPE delivers lasting durability, strong adhesion, and processing efficiency—ideal for grips, anti-slips, and soft-touch surfaces in electric shavers and consumer devices. read more
TPE Seal Technology Tailored for Security Devices
19.08.2025 TPE Seal Technology Tailored for Security Devices Discover how KRAIBURG TPE solutions enhance sealing in security devices like metal detectors with strong adhesion, reliable durability, soft-touch surfaces, and low emissions—ideal for safety and smart electronics applications. read more