Cold Bonding Slippers Manufacturing Standard Process

The production of cold-bonded slippers requires following a standardized process and paying close attention to detail to ensure the quality of the finished product. The specific steps are shown in the video, and are simple, efficient, and practical.

Step 1: Applying adhesive to the sole and machine-applying adhesive to the upper. The sole is placed on a worktable, and a special shoe adhesive is applied evenly by hand, ensuring no missed spots or excessive glue buildup. The upper is then automatically glued using a specialized machine, ensuring precise control of the amount applied, high efficiency, and even coverage, suitable for various slipper materials.

Step 2: Initial oven drying and secondary adhesive application. The glued sole and upper are placed in an oven at 45±5℃ for 3-5 minutes to activate the adhesive layer's tackiness.

After drying, a second layer of adhesive is applied, evenly covering the surface and enhancing bonding strength.

Step 3: Second oven drying. The sole and upper, after the second layer of adhesive, are placed back in the oven and dried using the same parameters to ensure the adhesive layer reaches optimal tackiness for subsequent bonding.

Step 4: Manual bonding of the upper. Within 40 seconds of removal, complete the bonding process, precisely aligning the upper with the sole.

Press and bond from toe to heel, ensuring a flat, tight fit without any crookedness or wrinkles, avoiding contact with the adhesive layer.

Fifth step: Machine pressing and fixing. Place the bonded slippers into the pressing machine and press for 8-10 seconds under 30-40kg pressure to ensure a strong bond and prevent separation. After removal, conduct a preliminary check for flatness.

Sixth step: Quality inspection. Inspect each slipper individually, cleaning excess glue and removing any excess adhesive. Test the bonding strength by gently pulling and pressing to prevent substandard products from proceeding to the next process.

Seventh step: Cleanliness check. Wipe the surface of the slippers with a soft cloth to remove dust and glue residue, ensuring cleanliness and compliance with relevant standards.

Eighth step: Packing and sealing. Place the qualified slippers into packaging bags, arrange them neatly, and seal them to prevent dust and moisture, protecting the product's appearance.

Ninth step: Packing and shipping. Pack the products into shipping cartons according to specifications, ensure proper protection, label with relevant information, and arrange for shipment to ensure safe delivery.

The entire production process requires strict adherence to standardized procedures and meticulous attention to detail to produce qualified cold-bonded slippers.

FAQ: Cold-Bonded Slippers Production Process

Q1: What are cold-bonded slippers?

A1: Cold-bonded slippers are footwear assembled using a room-temperature adhesive bonding process. Unlike injection molding or heat-pressing methods, cold bonding relies on specially formulated shoe adhesives and controlled drying to attach the upper to the sole, ensuring a strong yet flexible bond.

Q2: What are the key steps in the cold-bonding process?

A2: The process includes nine main steps:

Applying adhesive to the sole (manual) and upper (machine)

First oven drying (45±5℃ for 3–5 min) and second adhesive application

Second oven drying (same parameters)

Manual bonding of the upper (within 40 seconds after removal)

Machine pressing (30–40 kg pressure for 8–10 seconds)

Quality inspection (bonding strength, excess glue removal)

Cleanliness check

Packing and sealing into individual bags

Carton packing and shipping

Q3: Why is adhesive applied twice?

A3: The first adhesive layer is activated by oven drying, then a second layer is applied to enhance bonding strength. The second drying further optimizes the tackiness, ensuring a durable and long-lasting bond between the sole and the upper.

Q4: What are the critical parameters to control?

A4: Key parameters include:

Oven temperature: 45±5℃

Drying time: 3–5 minutes per cycle

Bonding time limit: within 40 seconds after removal from the oven

Pressing pressure: 30–40 kg

Pressing duration: 8–10 seconds

Q5: How is quality inspected in cold-bonded slipper production?

A5: Each pair undergoes individual inspection. Inspectors check for flatness, bonding strength (by gentle pulling and pressing), remove excess glue, and ensure no crooked or wrinkled attachment. Any substandard products are rejected before proceeding to packaging.

Q6: Why is the 40-second bonding window important?

A6: After the second oven drying, the adhesive layer maintains optimal tackiness for only a limited time. Completing the bonding within 40 seconds ensures maximum adhesion strength. Delaying may result in reduced bonding quality and potential sole separation.