A closer look at Loctite 402

1 min read

Henkel’s Loctite instant component bonding range has been augmented with a new product for the assembly of small components in high-speed production applications.

Loctite 402, an instant, high strength adhesive whose features and benefits are designed to help address industry challenges such as: productivity, reliability and design diversification. 


Loctite 402 is said to offer even faster fixture speed, superior heat performance and a unique, patented formula with upgraded health and safety credentials (formulated without the addition of traditional stabilisers such as HQ and MMBP). 

Loctite 402 develops handling strength twice as fast on most substrates by comparison with selected other assembly solutions (3 – 10 seconds), it provides an elevated level of performance that meets the demands of modern manufacturing. This fast fixture speed, achieved at room temperature, helps increase throughput and reduces work-in-progress for both manual and automated assembly.  Productivity can be increased further with Loctite dispensing equipoment. 

Loctite 402 is a single-component instant adhesive that bonds most metals, plastics and elastomers as well as hard-to-bond materials with the use of a primer. It gives users a single solution for multiple materials and components which helps reduce assembly costs and process complexity. 

Loctite 402 delivers more reliable performance compared to many traditional instant adhesives. It demonstrates strength retention on most metals up to 135°C - both tested at temperature ("hot strength") and room temperature ("heat aging"). Improved impact resistance is another feature of this adhesive compared with traditional instant adhesives.  

Loctite 402 also sets an important new health and safety milestone for instant adhesives. Its patented formula contains alternative raw materials that support the enhancement of worker and workplace safety.  Several instant adhesive ingredients have come under greater regulatory scrutiny in select regions of the world. Two of these are hydroquinone (HQ) and 2.2’-methylenebis (4-methyl-6-tert-butylphenol) – also known as MMBP - whose primary role is to ensure the adhesive remains liquid in the bottle for the duration of its shelf life. In response to regulatory change requirements and industry demand for safer assembly solutions, Henkel developed a novel stabiliser package which has allowed HQ and MMBP to be removed from the formulas for the most widely used instant adhesive products.  

This health and safety breakthrough, in combination with the other technical advancements, make Loctite 402 a desirable alternative to other fastening methods in an even greater number of manufacturing environments.