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Common Defects in UV Gel Nail Polish (Part 2)

Release time:

2026-04-29 16:53

Common Defects in UV Gel Nail Polish (Part 2)

During the application of UV gel polish, shrinkage is another common defect. Shrinkage occurs when the gel polish contracts inward from the nail edge or nail surface after curing, exposing part of the natural nail and directly compromising the integrity and longevity of the manicure. Unlike wrinkling, shrinkage is more closely related to adhesion and the material’s inherent shrinkage properties. Understanding the causes of shrinkage can help technicians identify and prevent this issue during application.

I. Manifestations and Impacts of Shrinkage

Shrinkage refers to the phenomenon where, after a gel polish has cured, the coating shrinks inward from the nail edge or develops contracted patches in the center of the nail surface, exposing portions of the bare nail. The exposed areas typically appear as irregular arcs or circles with well-defined borders. Shrinkage not only detracts from the overall aesthetic appeal of the manicure but also leaves the bare nail directly exposed, stripping it of the protective barrier provided by the gel coat. In severe cases, shrinkage can cause the edges of the polish to lift or even result in complete flaking, thereby reducing the longevity of the manicure.

II. Main Causes of Shrinkage

1. Inadequate cleaning of the nail surface is the primary cause of shrinkage in gel applications. The natural nail surface is coated with an oily film; if this film is not completely removed before application, the base coat will fail to form a strong bond with the nail. During curing, as the coating shrinks, areas with insufficient adhesion will be pulled toward the center, causing the edges to become exposed. Residual moisture or dust can also interfere with base-coat adhesion, resulting in localized, spot-like or patchy shrinkage.

2. Uneven application of the primer can also lead to shrinkage of the color gel. In areas where the primer is missed, the color gel and top coat come into direct contact with the nail, resulting in weaker adhesion compared with primed areas. During curing and subsequent shrinkage, this difference in adhesion causes the coating to contract toward the primed regions, exposing the unprimed areas. Similarly, applying the primer too thinly or failing to fully cover the edges can also result in insufficient local adhesion, creating a starting point for shrinkage.

3. Over-curing is a frequently overlooked cause. Excessive curing leads to an overly dense cross-linking network in the coating, resulting in increased shrinkage stress. If the adhesion between the base coat and the nail is insufficient to withstand this shrinkage stress, the coating will retract from the edges toward the center. Some users, in an effort to ensure complete curing, excessively prolong the irradiation time, which in fact increases the risk of shrinkage.

4. The product’s inherent shrinkage rate is also a factor. Shrinkage rates vary among different brands and product lines; the higher the shrinkage rate, the greater the internal stress generated during curing, and the more stringent the requirements for primer adhesion. When using high-shrinkage products, the likelihood of shrinkage-induced defects increases.

III. Conclusion

Shrinkage is a common issue in UV gel nail polish application that can compromise the integrity of the manicure. Its primary causes fall into four key areas: nail surface cleanliness, base coat application, curing control, and product selection. Residual oils on the nail surface prevent the base coat from adhering properly; uneven base coat application leads to inconsistent adhesion; over-curing increases shrinkage stress; and high-shrinkage products place even higher demands on adhesion. When these factors interact, the risk of shrinkage rises significantly. Understanding the root causes of shrinkage enables practitioners to take targeted preventive measures during application, ensuring full coverage and long-lasting adhesion for a flawless manicure.

Disclaimer: The above content has been compiled from public sources for reference only; if any infringement occurs, please contact us and we will address it promptly.

Boxing Recommended Products – UV Gel Nail Polish
Base coat
Product Model/English Abbreviation	Product Name/Product Type	Product Features
B-02H	Phosphate ester acrylate monomer	Enhance adhesion to substrates such as metal, glass, and plastic.
B-2016	Polyester acrylate	High molecular weight, excellent flexibility, strong adhesion, and low heat release
B-2018	Aliphatic polyurethane acrylate	Good adhesion, good flexibility, and water resistance.
Colored tape
Product Model/English Abbreviation	Product Name/Product Type	Product Features
B-151DM	Modified epoxy acrylate	Low halogen, yellowing resistance, excellent plating performance, and strong adhesion.
B-162	Epoxy acrylate	Fast curing, low odor, high gloss, and high fullness
B-166A	Modified epoxy acrylate	Good flexibility and strong adhesion
B-166A-85	Modified epoxy acrylate	Good flexibility, excellent adhesion, contains 15% HEMA
B-166A-85P	Modified epoxy acrylate	Good flexibility, excellent adhesion, contains 15% HEMA
B-27	Active amine photosensitizing promoter	Low color number, benzene-free, low odor, antioxidant and anti-polymerization
B-296	Aliphatic polyurethane acrylate	Fast curing, chemical resistance, yellowing resistance, and impact resistance.
Extended glue
Product Model/English Abbreviation	Product Name/Product Type	Product Features
B-210D	Aliphatic polyurethane acrylate	Fast curing, low exotherm, and good toughness
T-2022D	Aliphatic polyurethane acrylate	Non-stick, low heat generation, strong adhesion, high hardness
Sealant glue
Product Model/English Abbreviation	Product Name/Product Type	Product Features
B-376	Aliphatic polyurethane acrylate	LED yellowing is minimal, and the nail polish formulation exhibits excellent stability.
B-412T-6	Aliphatic polyurethane acrylate	Good toughness, tin-free, and excellent stability of the nail polish formulation.
Matte Sealing Layer
Product Model/English Abbreviation	Product Name/Product Type	Product Features
B-328M	Aliphatic polyurethane acrylate	Low gloss, low viscosity, excellent wettability, and a pleasant hand feel.
B-328R	Aliphatic polyurethane acrylate	Low gloss, excellent matting, good wetting, and a fine, smooth, and silky hand feel.
B-329D	Aliphatic polyurethane acrylate	Low irritation, low viscosity, excellent wettability, and a pleasant feel.
One-step adhesive
Product Model/English Abbreviation	Product Name/Product Type	Product Features
B-315	Aliphatic polyurethane acrylate	Wear and chemical resistance, high hardness, toughness, and yellowing resistance.
A-grade film
Product Model/English Abbreviation	Product Name/Product Type	Product Features
B-113	Bisphenol A epoxy acrylate	High hardness, high gloss, high fullness, containing 20% TPGDA
B-216	Aliphatic polyurethane acrylate	Fast curing, high fullness, and excellent toughness
B-268M	Aliphatic polyurethane acrylate	Good flexibility, good adhesion, good plating performance, and excellent hiding power.
B-619W	Aliphatic polyurethane acrylate	Fast curing, high hardness, good toughness, wear resistance, and chemical resistance.
Individual Recommendation
Product Model/English Abbreviation	Product Name/Product Type	Product Features
BM1211 (HPMA)	Hydroxypropyl methacrylate	HEMA-free, high strength, low irritation, high adhesion

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Common Defects in UV Gel Nail Polish (Part 3)

Common Defects in UV Gel Nail Polish (Part 1)