Why do labels tend to bulge and wrinkle after labeling?

Why do labels tend to bulge and wrinkle after labeling?

For products, the quality of labeling directly affects the product's appearance and brand image. However, various issues are inevitable during the labeling process, the most common being bulging, bubbling, and wrinkles after labeling. These issues not only affect the product's aesthetics but may also reduce consumers' desire to purchase, impacting the brand image to some extent.

This article will provide a detailed introduction to various factors that can cause labels to bulge, bubble, and wrinkle, and share some practical solutions. We hope this can provide valuable reference and inspiration for you in solving labeling issues.

Labeling and drumming

Bulging issues with labeling often occur in batches and are only discovered after labeling, sometimes only during pre-shipment inspections by end users, causing significant inconvenience and loss for end users. The main causes of labeling bulge are as follows:

01

Labels absorb water and expand

During processing, labels lose a certain amount of moisture. If the moisture in the environment suddenly increases during use, it will cause the label to absorb water and expand after labeling, especially for self-adhesive labels made of paper-based materials, where this issue is even more pronounced. Since the label is already attached to the object being attached, the expanded area will form bubbles or bulge.

In such cases, it is generally recommended to apply varnish or laminate the surface of self-adhesive labels made of paper surfaces to help block air moisture. If for special reasons it is impossible to polish or laminate, it is best to open the label and leave it for 24 hours to allow the label to fully balance with moisture in the air before applying. At the same time, if the item being labeled is easily affected by humidity, such as corrugated cardboard boxes, the same treatment should be applied.

02

The glue reacts chemically with the surface of the object being applied

Many of the items being labeled are typically plastic products, and various additives are added during processing. Some plastic products made from recycled plastics are even more complex in composition. The glue in self-adhesive materials is a chemical product that sometimes reacts with certain components in plastic products, producing gases. Because the label is attached to the surface of the object, the gas cannot be released, causing bubbles or swelling. In such cases, if the label is removed, noticeable changes will be found in the glue layer, such as a melting phenomenon.

When encountering such issues, it is recommended to switch to another adhesive material for labeling, and be sure to conduct labeling tests before processing to ensure no chemical reactions occur between the two before proceeding with production.

In addition, dirt such as dust and particles on the surface of the item to be labeled can prevent the label from adhering fully to the item, leading to bubbles. Therefore, before labeling, it is essential to ensure that the surface of the item being labeled is free of oil stains, dust, and impurities.

Label wrinkles

Label creases are one of the common issues during the labeling process. Sometimes label creases are found at the labeling site, and sometimes only after being left for a while after labeling. There are many causes for labeling wrinkles, mainly as follows:

01

The shape of the attached item

We know that self-adhesive labels are flat, so it's best for the object to be labeled to be flat for good labeling results. However, in practical applications, many bottles of the labeled object have a certain curvature. If the curvature is too large to form a spherical surface, the label will inevitably wrinkle after labeling because it cannot fully unfold.

If you encounter such issues, first observe whether the wrinkled areas are mainly concentrated at the edges of the label (sometimes the wrinkles are quite regular, because during automatic labeling, the labeling roller often squeezes the parts of the label that cannot fully unfold into the same position, forming creases). Then check the bottle body to determine if the curvature is too large, which can basically determine whether the wrinkles are caused by unreasonable design of the attached object's shape. If so, consider redesigning the shape of the item being attached.

02

Uneven pressure to appease the bid

All automatic labeling devices have labeling devices, and the pressure can usually be adjusted. Some surfaces of the objects being labeled are relatively soft, and if the pressure is too high, it can easily cause deformation and wrinkles on the label.

Therefore, when adjusting the pressure of the labeling device, it must be set within a suitable range; in principle, it should be adjusted to the point where the label is just being firmly applied.

03

Label absorbent

During the rainy season, air humidity can suddenly increase. If the moisture content in the label is lower than in the air, it can easily cause the label to absorb water and expand, especially for self-adhesive labels made of paper-based surfaces, where this phenomenon is particularly noticeable. In such cases, labeling causes the label to swell after being applied by absorbing water, which can easily cause wrinkles.

Therefore, before labeling during the rainy season, it is best to open the label and leave it for 24 hours to ensure the label is balanced with moisture in the air before labeling.

04

Transportation or storage issues

During storage or transportation, if labels are improperly stacked or squeezed, friction and compression between label layers may occur, leading to wrinkles.

Therefore, appropriate packaging materials and methods should be used during transportation, such as bubble wrap and cardboard, to isolate labels layer by layer to reduce friction and compression during transport. At the same time, avoid severe vibrations and impacts during transport to prevent damage to the labels.