Hot melt vs acrylic adhesive tape: which is right for your operation?

Hot melt and acrylic are the two main pressure-sensitive adhesives used for box sealing on polypropylene. They behave differently from the moment they’re applied. Those differences matter when you’re sealing hundreds of boxes a day in varied conditions. Choose the wrong adhesive type and you’ll get failed bonds in cold stores, degraded tape in warm despatch areas and higher cost per box over time.

There are four adhesive categories in the RAJAPACK range overall. This guide covers the two pressure-sensitive choices most operations decide between (hot melt and acrylic) plus natural rubber as the third pressure-sensitive option, used predominantly on PVC vinyl and kraft paper. The fourth category, starch-based vegetable adhesive, is used exclusively on water-activated paper sealing and works by a different mechanism; see our water-activated paper guide.

In this article, we’ll cover:

• What hot melt adhesive is and how it works (including the artificial hot melt rubber sub-grade used on filament and reinforced kraft)
• What acrylic adhesive is and how it differs
• How the two compare on initial tack, long-term bond and temperature
• Where natural rubber fits as a third option in the RAJAPACK range
• Why starch-based vegetable is a separate fourth category and where it’s used
• Which adhesive type suits cold storage, high-heat environments and long-term storage
• A practical decision guide so you can pick the right specification

What is hot melt adhesive?

Hot melt is a pressure-sensitive adhesive based on a rubber compound, applied at high temperature during manufacture. It bonds quickly on contact, which makes it the go-to choice for fast, high-volume packing lines sealing standard cardboard boxes at ambient temperatures. Most standard polypropylene tape in the RAJAPACK range use hot melt as the default adhesive type. Press it down and it grips almost immediately. That high initial tack is one of its defining characteristics.

The trade-off is temperature. Hot melt products in the RAJAPACK range are rated for application from 15°C upward. Below that, the adhesive loses tack and may not bond reliably to a cold box surface. Maximum hold temperatures vary across the range, with most products rated to 60°C and some lower-grade options rated to 25°C. In despatch areas exposed to direct sun or in transit vehicles during summer, hot melt can soften and lose seal integrity.

A note on terminology: ‘hot melt’ in the range covers two sub-grades. Standard hot melt is the rubber-based version applied to most polypropylene options. Artificial hot melt rubber is the synthetic version used on filament constructions and on the heavier reinforced kraft options where higher cohesive strength is needed. The two share the same temperature profile and instant-tack behaviour; the difference matters mainly when you’re matching a specific data sheet to a load-rated spec.

What is acrylic adhesive?

Acrylic is a pressure-sensitive adhesive based on an acrylic polymer. Unlike hot melt, it builds full bond strength over 24 to 72 hours after application – a process generally referred to as bond maturation. Initial tack is lower than hot melt, but the long-term bond is significantly stronger and more stable once it’s fully cured.

Acrylic options in the RAJAPACK range hold reliably from -5°C upward in standard products, with specialist options rated as low as -30°C for deep-freeze applications. Maximum hold temperatures are 60°C in standard products and 80°C in specialist grades. That makes it the right choice for cold chain logistics, outdoor storage and any operation where boxes face significant temperature variation. It’s also UV-resistant, so it won’t yellow or degrade in natural light over time.

Acrylic also tends to be quieter when unrolled, which makes it a reliable low-noise option. If noise levels matter in your packing area (for example, in fulfilment operations near office or customer service teams), it’s worth factoring in.

Where does natural rubber fit?

Natural rubber is the third adhesive type in the RAJAPACK range and the single largest adhesive category by product count. It’s used predominantly on vinyl packing tape and on kraft paper sealing. Natural rubber sits between hot melt and acrylic on initial tack and has a temperature profile similar to hot melt; most products are rated for 15°C minimum application, with maximum hold up to 65°C. It isn’t the standard choice for box sealing on polypropylene; if your application is on a coloured PVC backing or a kraft paper backing, you’ll most likely be specifying natural rubber by default.

And the fourth category: starch-based vegetable adhesive

Starch-based vegetable is the fourth adhesive category in the range, used exclusively on water activated tape (WAT). It’s not pressure-sensitive: the dry adhesive face activates when moistened with water, then bonds directly into the cardboard fibres rather than sitting on the surface. Because it works by a different mechanism, it isn’t directly comparable to the three pressure-sensitive options on tack and instant grip. The standard products are rated for application from -10°C to 40°C.

If your decision is between specifying water-activated paper or specifying a pressure-sensitive option, the choice is mostly about tamper evidence, recyclability and dispenser equipment rather than adhesive performance per se.

How the pressure-sensitive types compare

The comparison below covers the three pressure-sensitive adhesives, since they’re directly comparable on tack and temperature. Starch-based vegetable sits outside this comparison because it works by water activation rather than pressure-sensitive contact.

Temperature performance: which adhesive handles cold and heat better?

Acrylic is the right choice for any application involving cold storage, chilled transport or elevated heat. Hot melt isn’t rated for sustained use outside the 15°C to 60°C range covered by the RAJAPACK products.

Cold storage and freezer applications

In chilled warehouses, typically 2°C to 8°C, and in frozen storage below -18°C, hot melt loses tack and the seal can lift from the box surface. Acrylic stays flexible and grippy at these temperatures, maintaining a reliable bond on cardboard and corrugated board.

Minimum application temperature matters too. Hot melt products in the range are rated for 15°C minimum; below that, the adhesive won’t bond effectively to a cold surface. Standard acrylic products are rated to -5°C for application, with specialist options rated lower for deep-freeze use. Always check the product data sheet for the precise temperature range before specifying for cold-chain operations.

High-heat environments

Above 60°C, standard hot melt softens and the bond can fail. Despatch areas near loading bays in summer, vehicles that heat up in transit or areas near processing equipment all present this risk. Standard acrylic holds to 60°C and specialist grades hold to 80°C, making acrylic the reliable choice wherever heat is a factor.

Hot melt vs acrylic: initial tack and long-term bond

If your operation needs the seal to hold immediately on a fast packing line, hot melt is the better fit. Its high initial tack means you don’t need to apply pressure for long to get a working bond.

If your boxes sit in storage for more than a week, or go through multiple handling stages before delivery, acrylic gives better protection against seal failure. The 24- to 72-hour cure time means consistent application pressure matters, but the payoff is a bond that doesn’t creep or lift over time.

For mixed operations, where most goods are despatched within 48 hours but some go into longer storage, running a single acrylic specification across all lines is often the simpler approach. You pay a small cost premium, but you avoid juggling two adhesive types.

Which adhesive type is right for your application?

Choose the right adhesive by answering two questions: what temperatures will the seal face, and how long will boxes sit before despatch?

Use hot melt if:

• You’re packing in an ambient warehouse (15°C to 25°C) year-round
• Boxes are despatched within 24 to 48 hours of being packed
• You need high initial tack on a fast-moving packing line
• Cost per roll is a priority and temperature variation isn’t a factor

Most standard polypropylene options in the packing tape range use hot melt. If you’re sealing standard single wall or double wall boxes for next-day or two-day despatch at ambient temperatures, hot melt will do the job reliably and cost-effectively.

Use acrylic if:

• Your goods go into cold storage, chilled transport or freezer environments
• Boxes may be stored for more than a week before despatch
• Despatch area or transit conditions involve temperatures above 35°C or below 5°C
• You need UV stability for goods stored under natural light
• You’re packing goods with a long shelf life where seal integrity over months matters

Acrylic is common in food and pharmaceutical cold chain, outdoor and garden product distribution, and any operation where goods move through a temperature-variable supply chain. It’s also the standard choice for archival storage.

When the choice isn’t clear-cut

Some operations run both adhesive types: hot melt for standard ambient despatch and acrylic for cold chain or longer-term storage lines. This makes sense if your product mix genuinely spans both scenarios. Running a single acrylic specification across the whole operation also works. You trade a small cost premium for a simpler, more consistent packing process.

Which adhesive should you order?

Hot melt is the cost-effective, high-tack choice for standard ambient packing where goods move quickly. Acrylic is the durable, temperature-stable choice for cold storage, long-term bond requirements and operations with significant temperature variation. Natural rubber is the default on PVC vinyl and kraft paper backings rather than a standalone choice. Starch-based vegetable adhesive sits outside this list because it’s water-activated rather than pressure-sensitive; specify it via the water-activated paper category if tamper evidence or recyclability is the priority.

Before you order, check two things: the temperature range your seal will face, and how long your boxes typically sit before despatch. Those two answers will tell you which adhesive is right.

For an even deeper look at tapes, read our complete guide to adhesive tapes.

Key takeaways

• Hot melt has high initial tack and bonds on contact, making it suited to fast packing lines in ambient conditions where boxes are despatched within 48 hours. Hot melt products in the RAJAPACK range are rated for 15°C minimum application.
• Acrylic builds full bond strength over 24 to 72 hours but maintains reliable adhesion from -5°C to 60°C in standard products, with specialist options rated to -30°C and 80°C respectively. It’s the right choice for cold storage, chilled transport and high-heat environments.
• Hot melt isn’t suitable for cold chain or freezer applications. It loses tack below 15°C and can degrade above 60°C.
• Acrylic is UV-resistant and doesn’t yellow or lose adhesion over time, making it the better option for goods in long-term storage or exposed to natural light.
• Natural rubber is the third pressure-sensitive adhesive type in the range, used predominantly on PVC vinyl and kraft paper backings rather than as a standalone box-sealing choice.
• Starch-based vegetable is the fourth adhesive category, used exclusively on water-activated paper sealing. It bonds by water activation rather than pressure-sensitive contact and is the right choice when tamper evidence and recyclability are the priorities.
• For mixed operations, running acrylic across all packing lines covers every scenario at a small cost premium over hot melt.

FAQ: hot melt and acrylic adhesives

What does ‘hot melt’ mean?

Hot melt refers to the manufacturing process: a rubber compound is heated to a liquid state and applied to the backing. The result is a pressure-sensitive adhesive with high initial tack that bonds on contact at room temperature.

Can I use hot melt in a cold store?

No. Hot melt loses tack and seal integrity in cold storage and freezer environments. The hot melt products in the RAJAPACK range are rated for 15°C minimum application; below that, the adhesive won’t bond reliably. Choose acrylic for any operation below 15°C.

Is acrylic stronger than hot melt?

Acrylic has a stronger long-term bond once fully cured (24 to 72 hours after application). Hot melt has higher initial tack and grips faster on contact. Which is ‘stronger’ depends on whether you need immediate hold or lasting bond over time.

Why is my seal lifting off the box after a few days?

Lifting is usually caused by one of three things: temperature, surface condition or adhesive type. The seal may have been applied too cold, the box surface may have been dusty or damp, or the adhesive isn’t suited to the storage conditions. Switching to acrylic often resolves the issue.

What temperature range does each adhesive cover?

Hot melt products in the range are rated for 15°C to 60°C application and hold. Acrylic products are rated from -5°C to 60°C in standard grades, with specialist options extending to -30°C minimum and 80°C maximum. Always check the specific product data sheet for exact ratings.

Does UV light affect adhesive performance?

Yes. Hot melt yellows and the adhesive can dry out when exposed to UV light over time, reducing bond life. Acrylic is UV-resistant and maintains its properties and appearance in storage environments with natural light.

Which is quieter, hot melt or acrylic?

Acrylic is generally quieter on the roll. The rubber-based adhesive in hot melt produces more noise when unspooled. If noise levels in your packing environment matter, acrylic is the lower-noise option.

How do I know which adhesive type my current product uses?

Check the product data sheet or specification on the supplier’s website. The adhesive type will be listed alongside the temperature range and other specifications. RAJAPACK lists adhesive type on all product pages.

About the author

Sam Crosby-Browne: Sam Crosby-Browne is Senior Category Manager at RAJAPACK UK, responsible for packaging tapes, protective packaging and pallet wrap. He holds the CIPS Level 4 Diploma in Procurement & Supply and has spent 12 years in B2B category management, working with operations managers and packing teams across e-commerce, food and drink, manufacturing and third-party logistics.

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