Printing Perfection: Methods and Steps for Customizing Your PP Woven Bags

As a leading manufacturer of BOPP laminated PP woven bags (also known as polypropylene woven bags), we understand that these large sacks are essential for packaging a wide range of goods—from rice and animal feed to cement and chemicals. Beyond their function, the surface of these bags is a crucial canvas for identification and branding. Clear text, striking logos, and informative images are indispensable for helping consumers and logistics professionals quickly classify and recognize the contents.

When it comes to marking your woven bags, there are primarily two effective printing methods we use. Below is a detailed look at each process, ensuring your product presentation is as robust as our bags themselves.

Method 1: High-Speed Woven Bags Printing Machine (For Unlaminated Bags)

The woven bag printing machine offers a remarkably fast printing solution, but it’s important to note the prerequisite: this method is generally used before the plastic woven bag has been laminated with a BOPP film. For unlaminated bags, this machine-driven, cyclical process significantly reduces manual labor and boosts production efficiency.

🛠️ The Printing Steps:

1. Plate Installation: The first step is to accurately mount the customized text and images—the ‘printing plate’—onto the woven bag printing machine. This plate holds the precise design intended for the bag’s surface.
2. Ink Coating: Next, the printing ink is added to the machine. The mechanism then ensures that the installed printing plate is evenly coated and saturated with the chosen ink.
3. Cyclical Transfer: The machine cycles the bags through the system, where the inked printing plate precisely transfers the text and images onto the surface of the plastic woven bag.

Manufacturer Insight: While this is a machine-automated process, it still requires initial manual setup and oversight. The resulting speed and volume, however, offer substantial labor-saving benefits for high-volume, unlaminated bag orders.

Method 2: Versatile and High-Precision Screen Printing

Screen printing (or silk-screen printing) is another widely utilized technique, especially for applications requiring high detail or for printing onto finished/laminated bags. This method works by using pressure to force ink through a fine mesh screen onto the surface of the plastic woven bag.

⚙️ The Screen Printing Steps:

1. Screen Plate Preparation: The process begins by taking a photo-polymerized screen (a layout that has been dried), cutting it to the required size, and then mounting it onto a sturdy frame—such as wood or aluminum—to create the rigid screen board.
2. Ink Application (Squeegee Printing): The next critical step involves preparing the appropriate ink. The selected ink is then uniformly spread across the screen using a tool called a squeegee. This step, known as squeegee printing, ensures the ink is ready for transfer.
3. Transfer and Printing: The ink-coated screen board is then firmly positioned atop the plastic woven bag. Pressure is applied, forcing the ink through the open areas of the screen mesh and onto the bag’s surface, completing the print.

Quick Tip for Large Areas: For significantly large print areas, it is common practice to skip the squeegee step and pour the ink directly onto the screen before the transfer.

📝 Important Ink Note: The consistency of the ink is key to success in screen printing. Be careful not to use ink that is too thin (which might bleed) or too dry (which might not transfer), as either extreme can lead to a failed print.

🎯 The Golden Rule: Template Accuracy

Regardless of whether we utilize a high-speed printing machine or the meticulous process of screen printing, one fundamental rule applies to all large-scale production runs: The initial template must be flawlessly constructed.

Any mistake in the template—be it a misspelling, an outdated logo, or an incorrect image placement—will be replicated across every single plastic woven bag in the order. Our commitment to quality begins with precise template creation to ensure the information displayed on your bags is always correct and professional.

Do you have a specific design in mind for your BOPP laminated PP woven bags?

• Would you like to discuss the best printing method for your next order, or do you need assistance with your design template?