Product Introduction of Super Coating for High-grade waterproof Sandpaper

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Over the past decade, the development of high-grade waterproof sandpaper has seen remarkable progress, with grit sizes now extending up to 3000#,  In addition to the predominant sheet-shaped products, various other forms such as belts, perforated blocks, and circular discs have emerged. Moreover, the internal structure of the products has evolved to include super coatings, also known as anti-clogging coatings, applied as a third layer on the finished sandpaper surface. This transformation has elevated high-grade waterproof sandpaper from a single-function product to a versatile category encompassing diverse forms and structures.

Two Types of Super Coating Products

1. Heavy-Duty Abrasion for Sand Belts:

This type of super-coating is designed for high-pressure grinding applications using sand belts. The choice of high-quality abrasives, strong bonding, and a robust backing material allows for efficient and durable grinding. To meet the demands of high-pressure grinding, sand belts with super-coating structures are essential, ensuring highly effective grinding outcomes.

2. Anti-Clogging Super Coating for waterproof Sandpaper:

This category of super-coating is specifically designed to prevent surface clogging during sanding. The design and formulation of these coatings differ due to their distinct usage requirements. In this article, we will provide a concise overview of various aspects of super coating products for high-grade waterproof sandpaper.

The Role of Super Coating

In general, coated abrasive products inevitably experience issues such as abrasive grain shedding, abrasion blunting, and surface clogging during the grinding process. When these issues reach a critical point, the abrasive tool's performance deteriorates, ultimately leading to its disposal. While the first two scenarios are considered normal wear and tear, surface clogging represents abnormal wear and tear. This occurs when abrasive grains on the tool's surface become trapped by a swarf, obstructing the spaces between them and rendering them ineffective for grinding.

There are three primary causes of surface clogging:

1. Generation of Heat during Grinding:

The heat generated during grinding causes the bonding agent to soften and adhere swarf to the tool's surface, resulting in clogging.

2. Limited Space between Abrasive Grains:

When the spaces between abrasive grains are minimal, the swarf becomes embedded in these tight spaces, making it challenging to dislodge and leading to clogging.

3. Workpiece Material Properties:

Workpiece materials that are inherently soft or possess high adhesiveness can easily adhere to the tool's surface, causing clogging. Common examples include softwoods and soft metals like aluminum, copper, etc.

To address the issue of surface clogging, three approaches can be taken:

1. Use of High-Temperature Resistant Bonding Agents:

In the case of machine grinding with abrasive belts, which operate at high speeds and generate substantial heat, high-grade products like fully resin-bonded abrasive cloth and heavy-duty sand belts employ high-temperature-resistant phenolic resin binders. This significantly reduces clogging on the surface of the abrasive belt.

2. Sparse Coating for Abrasive Products:

This method, commonly used in the coated abrasive industry, involves increasing the distance between abrasive grains to enhance the inter-grain spacing. This minimizes the chances of the swarf becoming embedded and facilitates its dispersal. While effective, this method is primarily suitable for high-speed machine grinding conditions.

3. Application of Super Coating for waterproof Sandpaper:

Given that high-grade waterproof, sandpaper is primarily employed for manual grinding and polishing operations, where too few abrasive grains would hinder the process, the use of sparse coating is not feasible. Instead, super-coating proves to be the most effective solution. This specialized coating is applied to the semi-finished waterproof sandpaper surface. It fills the gaps between abrasive grains, effectively preventing swarf from embedding during grinding and polishing, thereby preventing clogging.

Supercoating maintains the original characteristics of high-grade waterproof sandpaper, including flexibility, high bond strength, and dense abrasive composition. It serves as a balanced solution, effectively preventing clogging while ensuring the sandpaper retains its sharpness throughout usage. This specialized coating exhibits minimal adhesion to the sandpaper surface, functioning solely to hinder swarf embedment during grinding and polishing. As a result, the super coating gradually wears off during use, ensuring that the sandpaper maintains its sharpness over time.