Climate change is one of the most critical factors affecting the structural integrity, printing quality, and overall performance of corrugated cardboard boxes and paper packaging. From high humidity in coastal areas to dry and cold inland areas, to continuous sunlight exposure during transportation, each climate condition poses unique challenges to packaging materials.
This guide is based on Crown Win Box manufacturer's over ten years of manufacturing experience and industry research, delving into how weather affects paper and cardboard, and sharing practical solutions to mitigate these impacts, suitable for manufacturers and businesses that rely on high-quality packaging.
How high humidity damages cardboard and paper packaging
Humidity is the main enemy of paper packaging, and its impact stems from the core component of cardboard: natural wood fibers. Even after chemical treatment and production, wood fibers still maintain their porosity, making cardboard inherently hygroscopic. This basic characteristic means that high humidity environments can cause a series of packaging quality problems.
The closer the region is to a warm climate, including China, Southeast Asia, and the eastern United States, paper packaging faces the most severe humidity challenge. Moisture in the environment can seep into the cardboard, damaging its structural integrity. One of the key indicators of packaging performance is stacking strength: when the relative humidity (RH) is 50%, the stacking strength of cardboard will decrease to 80% of its original strength. This is why summer, as the season with the highest humidity, becomes the most challenging period for packaging production, storage, and transportation.
In addition to structural failure, high humidity climate can also disrupt the entire packaging production process. Ink, laminating adhesive, and water-based varnish all contain moisture, and relatively high humidity environments can significantly prolong their drying time. Accelerating the drying process can cause partial solidification of ink and adhesive, resulting in fragile cardboard that absorbs water like a sponge. Additionally, due to increased ink viscosity, printed materials may appear blurry and of poor quality.
For enterprises that order customized packaging during high humidity seasons, extending the production cycle is a necessary condition to ensure that the packaging is fully dried.
Practical solutions for high humidity environments
1. During production and transportation, place desiccant bags in packaging to absorb excess moisture.
2. Use an industrial dehumidifier to maintain the relative humidity in the production workshop at 50-60% (in accordance with industry standards) to stabilize the drying time of ink and glue.
3. Store the finished product packaging in a cool and ventilated place;
4. Place the cardboard box flat outside the shipping box and use a fan/air conditioner to accelerate drying.
5. For the transportation of goods in high humidity areas, use PE film wrapping or waterproof coating to form a moisture-proof layer.
Dry/Cold Climate: Cardboard is Fragile and at Risk of Cracking
If high humidity climate can cause cardboard to become soft and weak, then excessively dry climate can bring the opposite problem: cardboard is fragile and cracked.
Cardboard stored in extremely dry environments for a long time will lose all residual moisture and become like a completely dry sponge - stiff, lacking flexibility, and easily torn under slight pressure.
This brittleness is particularly prominent in the folding and assembly process of corrugated cardboard boxes, where creases are the foundation of the box structure and therefore become the most prone to cracking, especially for offset printing boxes with substrate layers on the surface - cracks are very obvious here, not only affecting the function of the box, but also its appearance. Even slight handling may cause paper tearing, reducing the protective performance and brand image of the packaging.
Solutions for dry/cold climates
1. Prioritize film coating over water-based varnish: A thin layer of film coating (for environmental protection, it is recommended to choose biodegradable film) can protect the seal, prevent moisture loss, and reduce cracking.
2. Before folding, gently spray the cardboard with a spray bottle to supplement a small amount of water and improve its flexibility (avoid excessive wetting).
3. Use industrial humidifiers to maintain the relative humidity of the workshop and warehouse at 45-65%;
4. Store the raw paper and finished cardboard boxes away from cold and hot air vents.
5. Use elastic and environmentally friendly plastic connectors at the four corners of the cardboard box to increase flexibility and absorb shrinkage stress caused by temperature changes.
Avoid direct sunlight: it can cause photodegradation and structural degradation
Sunlight poses a threat to paper and cardboard packaging, as it damages the appearance and structure of the packaging through the process of photodegradation. Contrary to common belief, the damage is not caused by sunlight itself, but by ultraviolet (UV) radiation - especially for organic inks and dyes, which are sustainable choices for modern packaging.
Organic and natural inks quickly fade under ultraviolet radiation, making brand logos, patterns, and text dull and damaging the brand image. For printed packaging, this means a decrease in the visual appeal and market competitiveness of product packaging.
In addition to fading, ultraviolet radiation and solar heat can accelerate the drying of cardboard, intensify brittleness, and weaken the adhesion between corrugated cardboard layers. Even brief exposure to sunlight during transportation may lead to irreversible structural damage.
The Best Solution for Crown Win
1. All printing packaging uses soy ink: This is a sustainable alternative with a much lower photodegradation tendency than other biodegradable inks, and also has the advantages of reducing the risk of printer damage and easy reprinting.
2. Transport and store packaging in a cool and covered area;
3. Use UV resistant packaging materials during outdoor transportation.
4. Avoid placing packaging near windows or skylights in the warehouse;
5. Use opaque storage containers for high-value printing packaging boxes.
6. Apply an anti UV coating on the printing surface to provide an additional protective layer, especially suitable for retail or outdoor display packaging.
Crown Win packaging box experts suggest: 24/7 packaging performance guarantee
Crown Win packaging box manufacturers are committed to developing packaging products that can address global climate change. We always adhere to a comprehensive climate adaptive design from raw material storage to final delivery to ensure the stability of packaging performance. Here are our practical recommendations for businesses and peer manufacturers:
1. Standardized storage conditions: Keep all paper/cardboard materials at 20-28 ℃ and 45-65% relative humidity (industry gold standard) to maintain optimal moisture content (cardboard moisture content is 8-12%).
2. Customized surface treatment according to the region: film coating technology is used in dry/cold areas, waterproof coating is used in high humidity/coastal areas, and UV coating is used in sunny areas.
3. Optimize production cycle: For orders produced during high humidity seasons, add 2-3 days of drying time to ensure complete curing of ink/glue.
4. Preprocessing materials: For cross regional transportation, adjust the moisture content of the paper in advance to match the relative humidity of the target area (to avoid sudden expansion/contraction).
5. Investment in climate monitoring: Install real-time temperature/humidity sensors in workshops and warehouses, and automatically issue alerts when thresholds are exceeded.
Conclusion
Weather conditions are an inevitable factor for paper and cardboard packaging, but their negative effects are not inevitable. By delving into how humidity, dryness, and sunlight affect wood fiber materials, and combining appropriate material selection, production processes, and storage methods, companies can ensure that their packaging maintains structural strength, printing quality, and brand integrity under all weather conditions.
At Crown Win Box Manufacturer, we combine manufacturing technology with climate adaptation strategies to create customized paper and cardboard packaging that can reliably operate on a global scale. From eco-friendly film coatings to soy based UV resistant inks, our solutions aim to turn climate challenges into packaging advantages.
Contact us immediately to embark on your customized journey:
WhatsApp：0086 189 2583 8792
Email: maberry@crownwin.com.cn
