Not necessarily. The rubber content (the proportion of natural rubber) is indeed a key indicator, but it's not always the higher the better. It depends on the application and the manufacturing process.
Let me explain it to you in the most practical way that can be used in both exports and product selection:
Ⅰ. First, understand: What is the "rubber" inside the hot water bag?
The commonly referred to "gel content" means:
The proportion of natural rubber (NR) in the rubber compound
The remaining components are: fillers, vulcanizing agents, antioxidants, plasticizers, etc.
Ⅱ. High gum content: The advantages are obvious
The higher the content of the adhesive (for example, from 50% to 60% to 70%+):
- Better elasticity, soft texture, and less prone to hardening
- Stronger resilience, better resistance to aging and cracking
- Better air tightness, less prone to slow air leakage or water leakage
- High-grade texture, suitable for making high-end export products
Suitable:
- Export to Europe and America (requiring high standards and long-lasting durability)
- Thickened model, medical-grade, reusable long-term hot water bag
III. Excessive glue content: This actually has drawbacks.
Excessive natural rubber may lead to:
1. The cost has significantly increased (natural rubber is much more expensive than fillers)
2. It is too soft and lacks sufficient strength, prone to deformation and bulging
3. The heat resistance has deteriorated, and it becomes more prone to softening at high temperatures
4. The processing is difficult, and the shaping and vulcanization cannot be controlled well
So it's not the case that the higher the better; it needs to be balanced and proportioned.
IV. Practical Conclusion: How much gel content is considered "good"?
According to the industry standard, here is a direct and usable range for you:
1) Ordinary household / economical type
- Viscosity content: 35% - 45%
- Features: Sufficient, affordable, works fine for short-term use
- Suitable for: Domestic sales, low-price mass production
2) Mid-range export / regular quality
- Viscosity content: 50% - 60%
- Features: Balance of elasticity, strength and lifespan is the best
- This is the most reliable and cost-effective range
3) High-end / Thickened / Medical / Long-lasting
- Viscosity: 65% - 75%
- Features: Soft, durable, highly resistant to aging
- Suitable for: EU, Japan, high-end supermarkets
Industry consensus: 50% - 60% is the ideal range, offering the best balance between performance and cost.
V. When selecting products or conducting inspection, do not only focus on the glue content.
Also, consider these three points, which are more crucial than just the gel content alone:
1. Is the vulcanization complete (determining resistance to aging and non-stickiness)?
2. Is the thickness uniform (thin areas are prone to breaking)?
3. Are there anti-aging agents and reinforcing agents (the formulation is more important than simply mixing the rubber)?
