Industry News

Lamination and varnishing both fall under the category of surface finishing processes for products such as water bottle labels, vitamin medical bottle labels, and trademark labels after flexographic printing. Surface finishing not only improves the light resistance, water resistance, heat resistance, folding resistance, abrasion resistance, and chemical resistance of flexographic printed products such as shipping stickers, thermal labels, brown paper stickers, and gold foil shampoo stickers, but also increases gloss and artistic appeal, thereby enhancing their value. Lamination and varnishing are very similar, but there are also differences. This article will analyze them one by one from three perspectives: meaning, function, and process.

Flexo Printing Machine for Custom Label Printing

What Are Lamination and Varnish

Lamination is a paper-plastic composite process within composite processes, and it is a dry lamination method. Varnishing, on the other hand, is the process of applying coatings (commonly known as varnishes, which include film-forming resins, solvents, and additives) to the surface of printed materials, allowing them to level and dry.

Lamination

Lamination is a post-printing process in which a plastic film coated with adhesive is applied to the surface of flexographic printed products such as water bottle label, wine packaging label sticker, and plastic bottle label sticker. After heating and pressurizing, the printed material and the plastic film are tightly bonded together, resulting in a paper-plastic composite product.

Varnish

Varnishing is a process in which a layer of colorless and transparent coating is applied (or sprayed or printed) to the surface of printed materials such as transparent logo stickers, QR code barcodes, and perfume cosmetics bottle labels. After leveling and drying (calendering), a thin and uniform transparent glossy layer is formed on the surface of the printed material.

Flexographic Printing Machine for PE PP Film Sticker Label

What Are the Functions of Lamination and Varnish

Applying a plastic film (coating) or a varnish to the surface of printed materials such as hot stamping clear gold foil stickers, thank you sticker labels, and drinking water bottle labels gives them properties such as abrasion resistance, moisture resistance, water resistance, and stain resistance. This not only protects the printed materials and extends their lifespan but also increases the gloss of the surface, enhancing their appearance and visual appeal, thereby elevating the product's perceived quality and increasing its added value.

Label Printing Machine for Shipping Label Sticker

The Differences Between Lamination and Varnish Processes

Lamination and varnishing can enhance the surface properties of flexographic printed products such as high grade matt finish label stickers, jar packaging labels, and waybill barcode stickers, increasing gloss and artistic appeal, and improving economic value, but they differ significantly in terms of the process.

Lamination Processes

The lamination process can be divided into immediate lamination process and pre-coated lamination process.

Immediate Lamination Process

In other words, the immediate lamination process involves using a roller coating device to evenly coat the surface of a plastic film with an adhesive. After passing through a drying device, the solvent in the adhesive is evaporated. Then, the printed material is drawn onto a thermoforming laminating device, where the plastic film and the printed material are pressed together to complete the lamination process. Simultaneously, rewinding is completed, followed by storage, shaping, and slitting. From the perspective of adhesive materials, coating can be further divided into solvent-based adhesive lamination and water-based adhesive lamination.

Pre-Coated Lamination Process

The pre-coated lamination process involves a professional manufacturer pre-applying a quantitative and uniform amount of adhesive onto a plastic film, followed by drying, winding, and packaging to produce a finished product for sale. Then, a processing company uses a lamination machine without an adhesive coating device to perform hot pressing, thus completing the lamination process for printed materials such as adhesive bopp mineral water bottles labels and luxury waterproof logo cosmetics vinyl labels.

Flexo Printing Machinery for Beer Bottle Label

Varnish Processes

Depending on the type of varnish, varnishing processes can be mainly divided into solvent-based varnishing, water-based varnishing, and UV varnishing.

Solvent-Based Varnishing

Solvent-based varnishing refers to a varnishing process that uses benzene, esters, and alcohols as solvents and thermoplastic resins as film-forming resins. During the varnishing process, the solvent evaporates while the resin undergoes polymerization or cross-linking reactions to form a film.

Water-Based Varnishing

Water-based varnishing is a varnishing method that uses water-soluble resins or different types of water-dispersible resins as film-forming substances. Water-based varnishes use water as a solvent, and no organic solvents are released during the coating and drying process. The varnishing process is odorless, environmentally friendly, and harmless to humans, and is widely used in the packaging of tobacco, pharmaceuticals, food, cosmetics, and other commodities.

UV Varnishing

UV varnishing, also known as ultraviolet radiation drying varnishing, utilizes ultraviolet light to instantly trigger a photochemical reaction in the varnish, forming a glossy coating with a network chemical structure on the surface of printed materials such as thermal printer labels, advertising stickers, and QR code labels. Its curing process is the same as that of UV inks, and it is characterized by high gloss, strong heat and abrasion resistance, fast drying, safety, and environmental friendliness. It has broad market prospects and, like water-based varnishing, is widely used in the packaging of pharmaceuticals, food, and other products.

Flexo Press for Beverage Label

In conclusion, while lamination and varnishing are both crucial post-printing surface finishing processes, they differ in meaning, function, and technique. By accurately grasping these differences and tailoring strategies to the specific materials used, every label produced by a flexographic printing press can achieve a perfect balance between practical performance (wear resistance, water resistance, and fold resistance) and visual appeal (gloss and artistic appeal), ultimately radiating a lasting and dazzling brilliance on market shelves.