What is Acid Free Paper?

Introduction

Whether you're in the printing industry or just a curious reader, you may have heard of acid free paper. But what exactly does it mean? In this article, I’ll walk you through what acid free paper is, its advantages, and how it’s used. These insights might come in handy when you're choosing a paper supplier—read on to learn more!

Acid Free Paper Definition

As the name suggests, acid free paper has a pH level of 7 or above, meaning it contains no free acids after production. During the papermaking process, paper is often treated with sizing agents to improve its usability. Traditional sizing methods can introduce active acids into the paper, making it acidic. Additionally, traditional paper typically contains lignin, which breaks down over time and generates acidic compounds.

In contrast, acid free paper is made using a neutral sizing process. Manufacturers also add buffering agents like calcium carbonate during production, which neutralize any residual acidity in the paper.

The Advantages of Acid Free Paper

• High Strength

  Did you know that acid free paper is used in making U.S. currency? That’s because it needs to be extremely durable. A single banknote may be folded thousands of times, and acid free paper is designed to withstand that kind of repeated stress without tearing, making it highly resistant to folding and wear.

• Outstanding Durability

  Since acid free paper doesn’t contain acidic substances, it doesn’t suffer from the same degradation as traditional paper. Acidic compounds in regular paper can weaken its structure, cause discoloration, and lead to brittleness over time. Acid free paper, on the other hand, remains strong and stable, making it ideal for long-term storage.

• Mold and Pest Resistance

  With a pH of 7 or higher, acid free paper is less likely to absorb moisture, which helps prevent the growth of mold. Furthermore, the neutral sizing agents and calcium carbonate used during production enhance the paper’s structure and offer some resistance to insects.

• Environmentally Friendly

  Because it lacks harmful acidic substances, acid free paper has a lower environmental impact. Its longevity also means less frequent replacement, which reduces paper consumption and waste. This makes acid free paper a more sustainable choice.

The Applications of Acid Free Paper

• Archival Storage

  Acid free paper is also known as archival paper because it’s commonly used to make archival folders and envelopes. Despite the digital age, many governments and institutions still store critical documents on paper. Acid-free archival materials ensure these documents remain intact over long periods, protected from mold and insect damage.

• Photograph and Film Protection

  Acid free paper is used to protect photographs, negatives, and other delicate media from abrasion and degradation, preserving their quality and readability.

• Office and Educational Use

  In offices and educational institutions, acid free paper—especially woodfree offset paper—is favored for its neutral pH and physical stability. It's often used for premium printing and high-quality image reproduction, offering crisp and lasting visual output.

  
  

Conclusion

That wraps up our introduction to acid free paper. If you have any questions, feel free to contact us at Golden Paper. We’ve partnered with clients around the world to create custom paper solutions tailored to their needs. If you’re sourcing paper products, we’d love to help!