What can hot melt adhesive stick? One time explanation of the scope of application and unsuitable scenarios of hot melt adhesive

Hot melt adhesive is not a “jack of all trades”, it excels in one type of material but also has obvious shortcomings. Before selecting, it is important to clarify what it can and is not good at sticking, which can help avoid many detours. Below are the actual applications covered by Sunlife, explaining the scope and boundaries of the application of hot melt adhesive in one go.

1、 What is the best adhesive for hot melt glue (EVA type)

Sunlife’s hot melt adhesive is mainly EVA, which belongs to thermoplastic adhesive – heated and melted, cooled and solidified, with a physical state that changes with temperature and a chemical state that remains unchanged. The most suitable material for it isPorous, with certain surface energy, able to be infiltrated or adhered by colloidsof

• Paper/Paper ProductsBooks, brochures, notebooks, cardboard boxes, paper boxes, business cards – these are the biggest uses of hot melt adhesive, and Sunlife book adhesive and graphic store adhesive are all in this category;
• Pearl cotton (EPE)Foamed polyethylene cushioning material, widely used in the packaging industry, Sunlife has specialized pearl cotton glue (glue tank 140-160 ℃, drum 110-130 ℃);
• Fabric/non-woven fabricPartial clothing lining, filter element, non-woven fabric composite;
• Wood/Edge bandingEdge banding of boards and partial bonding of wooden products;
• Partial plasticPE, PP, etc. that have undergone surface treatment, or plastic parts that do not require extreme adhesive strength.

2、 Hot melt adhesive is not very good at (or can hardly stick to) materials

Choosing the wrong material, even the best glue is useless:

• Metal, glass, ceramicLow surface energy and non permeability make it difficult for hot melt adhesive to form effective bonding;
• Untreated PP/PE low surface energy plasticWeak direct adhesion, surface treatment is required first;
• Elastomers (TPE, rubber)After curing, hot melt adhesive tends to be hard and does not match the hardness of the elastomer, making it easy to detach;
• Oil stains, dust, and damp surfacesAny glue is afraid of this, it must be cleaned and dried before sticking;
• Continuous high temperature or long-term water immersion environmentHot melt adhesive has a softening point, it will soften at high temperatures and become ineffective after prolonged immersion in water.

3、 How to choose the right model based on materials

There is still a difference between “being able to stick” and “sticking firmly and using for a long time”, and there is still one “choosing the right model”:

• Books and magazines/picture books → special adhesive for book and magazine binding (back adhesive and edge adhesive are used separately);
• Graphic and Text Quick Printing → Graphic and Text Store Adhesive (S-393 Mid End/S-395 High End Low Temperature Resistant);
• Packaging/cardboard boxes → packaging hot melt adhesive;
• Pearl cotton buffer → Pearl cotton special adhesive (EVA or polyolefin, selected according to odor/drawing requirements).

turnMaterial type+usage environment (temperature/contact with water)+equipment speedTell Sunlife that the technology will provide models and process cards based on real-life scenarios, rather than just reporting a universal ‘hot melt adhesive’.

Frequently Asked Questions

Can hot melt adhesive stick to metal?

Conventional EVA hot melt adhesive has weak adhesion to low surface energy hard materials such as metal and glass, and is generally not recommended. This type of working condition requires the use of structural adhesive or specialized metal bonding solutions.

Can all plastics be glued with hot melt adhesive?

It cannot be generalized. Processed PE/PP can be used, but elastomers (TPE/rubber) and untreated low surface energy plastics are difficult to adhere firmly; Ask Sunlife Technology for more accurate material samples.

The value of hot melt adhesive lies in its ability to stick quickly and firmly to the right material, rather than being universal. First, clarify the three things of “what to stick, where to use it, and what equipment to use”. Sunlife uses material matching models and process cards, which saves much more time than blindly testing glue.

Related Reading:Where should we look for pearl cotton bonding? Conduct on-site acceptance using “appearance, positioning, and strength after cooling”