Kraft paper tape with increased wet strength

Kraft paper tape with increased wet strength- This is a fairly popular product, especially in the field of packaging and fastening. But often there is a feeling that 'durable' and 'moisture resistant' are one and the same thing. And this is where the interesting rub lies. Often a material is chosen based on visual impressions and stated characteristics, but the actual behavior of the tape in the field can differ greatly from what is expected. We came across situations where the tape simply fell apart upon contact with moisture, while others, seemingly similar, held up quite well. And this is not just a marketing ploy - this is a real nuance that requires understanding.

What do we mean by 'increased wet strength'?

The concept of 'strength' itself is multifaceted. We are talking not only about maximum tensile strength, but also about resistance to tearing, as well as the ability to maintain structural integrity when exposed to moisture. Plain kraft paper, especially untreated paper, quickly loses its properties when wet. The fibers swell, lose their stiffness, and of course, their ability to withstand the load is significantly reduced. It's important to understand here that we're not talking about waterproofing. We are talking about reducing the negative impact of moisture and maintaining the performance of the tape in conditions of high humidity or short-term contact with water. Influence not only the mechanical properties, but also the adhesion to the surface to which the tape is glued.

Our company, Enping Sanli Adhesiv LLC, has been developing and producing adhesive tapes, including those that require increased moisture resistance, since 1997. We are constantly experimenting with different types of kraft paper and impregnation, analyzing the test results under a variety of conditions. And experience shows that it is important not only to use kraft paper, but also to process it correctly.

Effect of Kraft Paper Type

The type of kraft paper is the base. There are many varieties that differ in the origin of the fiber, production method and, of course, properties. For example, tape made from recycled materials often has poorer moisture resistance than tape made from virgin cellulose fiber. Strong kraft paper, obtained through special processing, can withstand higher loads and has better tear resistance, especially when wet. We often recommend our clients to choose this option if the durability of the tape is important.

It is also important to consider the degree of impregnation of the paper. Impregnation with various compounds - impartial resins, waxes, polymers - can significantly increase the moisture resistance and mechanical properties of the tape. But here it is important to choose a composition that will not affect the adhesion of the tape to the surface. This is a complex task that requires in-depth knowledge of the chemistry of adhesives and paper. Our laboratory constantly conducts tests to determine the optimal composition of the impregnation.

Processing and impregnation methods

The impregnation process of kraft paper is a separate area of expertise. There are several methods: surface impregnation, deep impregnation, coating. Each method has its own advantages and disadvantages. Surface impregnation is the simplest and most economical option, but it provides the least degree of protection from moisture. Deep impregnation is a more complex and expensive process, but it provides higher moisture resistance. Applying coatings (for example, polymer) is an effective way to protect the tape from moisture and mechanical damage, but it can affect its flexibility and elasticity. When choosing an impregnation method, it is necessary to take into account the requirements for the final product and its operating conditions.

For example, we have developed a special impregnation method using acrylic resins, which provides high moisture resistance and mechanical strength of the tape, without reducing its elasticity. This method is used in the production of tapes for packaging food and other products that are exposed to moisture. This is the result of long experiments, when we tested different additives and their concentrations in order to achieve the optimal balance between the properties of the tape and its cost.

Real experience: example with packaging of construction materials

We recently worked with a company that produces building materials. They needed a tape to wrap pallets of boards that would withstand long-term outdoor storage exposed to rain and snow. Initially, they used regular kraft paper, but it quickly lost its properties and tore. We offered them a tape made of high-strength kraft paper with additional impregnation with polyurethane. After testing, the tape showed excellent results: it passed all tests and did not lose its properties even after prolonged exposure to moisture. The client was very pleased with the result.

This example shows that choosing the right material and processing method is a key factor in ensuring belt longevity and reliability. You should not skimp on the quality of materials if this may lead to problems in the future. Moreover, it is worth considering the specific operating conditions of the belt and choosing the material that is best suited for these conditions. We have tapes designed specifically for a variety of applications, from lumber packaging to agricultural product protection. We are always ready to help clients choose the best option.

Difficulties and pitfalls

Despite all our developments and experience, sometimes difficulties arise. For example, when using aggressive chemicals (acids, alkalis), even impregnated kraft paper can be destroyed. Or, for example, at very low temperatures, some polymer coatings can become brittle and crack. Therefore, it is important to consider all factors that can affect the properties of the tape and choose a material that is resistant to these factors.

In one of our attempts to develop tape for use in heavy industrial applications (such as securing large metal structures), we used very thick kraft paper and a multi-layer coating. But during testing, the tape turned out to be too rigid and fragile. We revised the coating composition and the structure of the tape, and as a result we received a product that fully met the customer’s requirements.

Conclusion: a look from the inside

So,Kraft paper tape with increased wet strength– it’s not just a pretty name. This is a real product that can solve many problems. But for this it is important to understand the characteristics of materials, processing methods and operating conditions. Enping Sanli Adhesive LLC is always ready to provide professional advice and help you choose the best tape option for your business. We believe that a quality product is the key to success.