2025 Diaper Material Selection Guide: Which Core Materials Enhance Absorbency And Breathability?

In the competitive diaper market, **absorbency and breathability** are core metrics for consumer decisions and key drivers of brand differentiation. Driven by demographic shifts and consumer upgrades in 2025, the demand for "ultra-thin dryness + natural breathability" in baby diapers continues to rise, while requirements for "efficient absorption + comfortable fit" in adult incontinence products become stricter. As a material supplier, the precise selection of a core material combination directly determines a product's market acceptance. This article deconstructs key materials from a structural perspective, combined with 2025 technology trends, to provide a systematic selection reference.

I. The Absorbent Core: The Engine of Dryness

The absorbent core is the "heart" of the diaper. Its material composition directly impacts absorption speed, water-locking capacity, and rewet rate. The 2025 technology upgrades are focused on material composites and performance optimization.

(A) Super Absorbent Polymer (SAP): The Core Carrier for Absorption

As the core component, Super Absorbent Polymer (SAP) can absorb hundreds to thousands of times its weight in water. Its performance upgrade is a primary technological direction for 2025. SAPs are categorized by chemical structure, with medical-grade SAPs being the mainstream choice due to their excellent water retention.

Key SAP innovation directions to watch in 2025 include:

• Nano-Crosslinked SAP: Utilizes nanotechnology to optimize the molecular structure, increasing absorption speed by over 40% compared to traditional products. It also enhances mechanical strength, reducing rewet issues caused by gel crushing.

• Bio-based SAP: Produced from renewable resources, it achieves partial degradation while maintaining high absorbency, aligning with environmental policies. Its penetration in adult incontinence products has already reached 28%.

• Multifunctional Composite SAP: Incorporates antibacterial ingredients or odor-absorbing factors to achieve antibacterial and deodorizing functions on top of water-locking, suitable for high-end infant and adult care.

When selecting, focus on three key metrics: Saline Absorption Capacity (simulating urine, should be ≥30g/g), Absorption Speed (≤30 seconds is ideal), and Absorbency Under Pressure (AUP) (reflects water-locking stability, needs to be ≥20g/g).

(B) Fluff Pulp: SAP's Performance-Enhancing Partner

Fluff pulp, processed from wood pulp, has good moisture absorption and breathability. Its main role is to disperse SAP particles, rapidly conduct liquid, and provide a fluffy texture. In 2025, optimizing the ratio of fluff pulp to SAP is key to enhancing performance.

For high-end ultra-thin products, a "low fluff pulp + high SAP" combination (with >70% SAP) achieves efficient water-locking. For high-volume needs like adult night-use, select long-fiber fluff pulp (≥3mm) to create a "rapid absorption - strong locking" synergy. Ensure the pulp is free of fluorescent agents.

(C) Absorbent Core Composite Technology: Key to Maximizing Performance

The mainstream "sandwich composite structure" is standard for 2025: an acquisition distribution layer (ADL) non-woven on top, a mixed layer of SAP and fluff pulp in the middle, and a water-locking non-woven at the bottom. Some high-end products introduce "gradient absorption design," with layered SAP particles of different sizes to achieve "fast initial absorption, then deep water-locking," reducing the rewet rate to below 5%.

II. The Breathable Layer: Balancing Leak-Proof and Dryness

The core mission of the breathable layer (backsheet) is to allow air circulation while blocking liquid leakage. Material innovation here is crucial for skin health and comfort, showing dual trends of "functional upgrading + environmental transformation" in 2025.

(A) Breathable Backsheet: The Fulcrum of Balance

Traditional polyethylene (PE) backsheets are leak-proof but lack breathability. 2025 breakthroughs focus on microporous structure optimization. Microporous breathable films, with pore sizes controlled between 0.1-1μm, block liquids (via surface tension) but allow water vapor to pass freely, achieving breathability of 5000g/m²・24h or more.

Innovative backsheet materials to focus on:

• Bio-based Degradable Backsheet: Based on PLA and PBAT, it can degrade in 6-12 months. Its penetration in adult incontinence products reached 28% in 2024.

• Composite Functional Backsheet: Combines a microporous film with a non-woven fabric, adding a skin-friendly coating to enhance both breathability and softness for sensitive infant skin.

• Silent Breathable Film: Reduces friction noise through material modification, addressing privacy concerns in adult use. Its penetration in retail channels has hit 63%.

Selection: Prioritize "high breathability + soft" composite backsheets for infants (≥3000g/m²・24h). For adults, focus on "high barrier + silent" materials.

(B) Breathable Non-woven Fabric: Channel for Internal Circulation

Located between the core and the backsheet, this non-woven fabric handles moisture wicking and air circulation. The 2025 mainstream choice is **hot-air non-woven fabric**, which forms air channels with its 3D structure and is treated to be hydrophilic to speed up liquid transfer.

It's recommended to choose a weight of 25-35g/m². For high-end products, bamboo or cotton fiber composite non-wovens can be used to enhance natural feel and moisture-wicking.

III. The Skin-Friendly Topsheet: The First Line of Defense

While the topsheet doesn't determine total absorbency, it impacts liquid acquisition speed and skin contact experience, significantly enhancing the overall feeling of dryness.

The 2025 mainstream topsheet is a **spunbond-hot-rolled composite non-woven**. It uses an "embossed diversion design" to reduce skin contact area and accelerate liquid penetration to the core. Focus on three characteristics:

• Hydrophilicity: Treated with a hydrophilic finishing agent, the contact angle should be ≤30°.

• Softness: Hand feel hardness should be ≤80mN to reduce skin friction.

• Breathability: Air permeability ≥1500mm/s to promote air circulation.

For sensitive skin, functional topsheets with chamomile extract or prebiotic ingredients can be used. For adult products, an anti-pilling topsheet is recommended for long-term comfort.

IV. 2025 Diaper Material Selection Practical Strategy

(A) Precise Selection Matrix by Scenario

(B) Environmental Compliance and Adaptation

With "Dual Carbon" goals and stricter regulations, material selection must consider sustainability. Gradually introduce bio-based SAP (20%-30% substitution) for infant products. Prioritize degradable backsheets (PLA/PBAT composite) for adult products. Ensure all materials pass OEKO-TEX® 100 certification. For export, materials must also comply with EU REACH regulations.

(C) Balancing Cost and Performance

To improve performance while controlling costs, adopt an "upgrade core materials + optimize auxiliary materials" strategy. Prioritize high-performance SAP (like nano-crosslinked) while using cost-effective domestic fluff pulp. For mid-market backsheets, use a "microporous PE film + standard non-woven" composite; reserve bio-based composites for the high-end market. This can increase breathability by over 30% with a cost increase of no more than 10%.

V. Conclusion

Diaper material selection in 2025 has entered a new era of "precise matching + technological innovation." Enhancing absorbency and breathability no longer relies on a single material upgrade but requires synergistic optimization of the absorbent core, breathable layer, and topsheet.

Material suppliers must track the trends of **high-performance SAP, eco-friendly backsheets, and functional topsheets**. By addressing the differentiated needs of infant and adult markets, they can provide material solutions that are "performance-driven, cost-controlled, and compliant." As nanotechnology and bio-based materials see further application, material innovation will be the core driver of the diaper industry's development.