What Are Acrylic-Based PSAs?

Acrylic-based PSAs are adhesives made from acrylic polymers, which are typically derived from esters of acrylic acid. These adhesives exhibit pressure-sensitive properties, meaning they bond to surfaces when light pressure is applied, without the need for additional heat or solvents.

Key Characteristics of Acrylic-Based PSAs
1. Excellent Adhesion:
• They offer strong and lasting adhesion to a wide range of surfaces, including smooth, rough, and low-energy substrates like plastics.
2. High Durability:
• Acrylic PSAs are resistant to environmental factors such as UV light, heat, and moisture, making them suitable for outdoor applications and long-term use.
3. Wide Temperature Range:
• They maintain their performance across extreme temperatures, from freezing conditions to high heat, without losing adhesion or cohesion.
4. Chemical Resistance:
• Acrylic PSAs resist many chemicals, solvents, and cleaning agents, which is critical for industrial, medical, and packaging applications.
5. Aging Stability:
• They are less prone to yellowing or degrading over time compared to rubber-based adhesives, ensuring a clean and professional appearance over time.

Why Are Acrylic-Based PSAs Important in Custom Label Manufacturing?
1. Versatility:
• They work well with diverse label face materials, such as paper, polypropylene, polyester, and other films.
2. Performance in Challenging Environments:
• Their resistance to harsh conditions makes them ideal for automotive, aerospace, medical, and outdoor product labeling.
3. Customizable Properties:
• Acrylic PSAs can be formulated to achieve specific characteristics, such as ultra-high tack for difficult-to-bond surfaces or low tack for repositionable labels.
4. Sustainability Considerations:
• Acrylic PSAs can be water-based (emulsion) or solvent-based. Water-based options are more environmentally friendly, offering reduced VOC emissions compared to solvent-based counterparts.

Types of Acrylic PSAs
1. Water-Based Acrylics:
• Environmentally friendly with low VOCs.
• Ideal for food packaging labels and other eco-conscious applications.
2. Solvent-Based Acrylics:
• Offer higher resistance to extreme temperatures and chemicals.
• Commonly used for industrial and automotive labels.
3. UV-Curable Acrylics:
• Cure under UV light, providing rapid processing and excellent adhesion.
• Often used in high-speed label manufacturing.

Advantages Over Rubber-Based PSAs
• Environmental Resistance: Acrylic PSAs are better suited for outdoor use.
• Long-Term Stability: Acrylic PSAs maintain their properties over time, while rubber-based adhesives may degrade.
• Wider Application Range: They bond well to high-energy and low-energy surfaces, unlike rubber-based PSAs, which may struggle with certain plastics.

Applications
1. Product Labels:
• Acrylic PSAs are ideal for food, beverage, and cosmetic labels due to their clean and long-lasting adhesion.
2. Industrial Labels:
• Used for durable goods, electronics, and machinery requiring resistance to chemicals and abrasion.
3. Medical Labels:
• Frequently employed in labeling medical devices and pharmaceutical packaging due to their hypoallergenic properties (in water-based formulations).
4. Outdoor Labels:
• Used for applications that require weather resistance, such as garden product labeling and automotive decals.

Challenges:
Adhesion Speed:
• They may take longer to achieve full adhesion compared to rubber-based PSAs, which provide immediate tack.

Siliconised backing paper is a type of release liner used in pressure-sensitive label applications. Its primary function is to support the adhesive label until it is applied to the desired surface. The “siliconised” aspect refers to the application of a thin silicone coating on one side of the paper, which ensures the adhesive doesn’t stick permanently to the backing material. Instead, the label can be easily peeled off when needed.

Key Features of Siliconised Backing Paper:
1. Release Properties:
• The silicone coating provides a smooth surface with low surface energy, enabling the adhesive to release easily without leaving residue.
2. White Backing:
• The “white” descriptor indicates the color of the paper, which is often chosen for its clean, professional appearance and contrast, making it easy to identify labels or markings on the backing.
3. Support and Stability:
• Backing paper adds rigidity and support to the label, especially during printing, cutting, and application processes.
4. Eco-Friendly Considerations:
• Many siliconised papers are recyclable, but this depends on the specific type and the availability of appropriate recycling facilities.

Why is it Important in Label Manufacture?
1. Facilitates Printing and Handling:
• The backing material ensures that labels stay intact during printing (e.g., digital or flexographic) and die-cutting processes.
2. Precision in Application:
• It enables precision in label application, whether manually or through automated application systems.
3. Compatibility with Adhesives:
• The silicone coating is tailored to work with pressure-sensitive adhesives (PSAs), maintaining their functionality and ensuring proper adhesion to the end product.
4. Versatility:
• It supports labels made from various face materials like paper, polypropylene, or specialty films, enhancing their adaptability across industries (e.g., cosmetics, food packaging, industrial labeling).

Limitations or Challenges:
• Environmental Impact:
• While some siliconised papers are recyclable, the silicone coating can complicate the process. There is a growing focus on developing more sustainable alternatives.
• Cost:
• Siliconised backing paper may be more expensive than non-siliconised options, but its performance often justifies the price."