HELLO, PUMA!

MARCH 11, 2024 UPDATE:

We’re very happy to continue tuning our materials to fit your needs. The samples in the box sent to you on March 7th, 2024 have demonstrated improved bonding characteristics and flexibility. Below is a description of each sample, along with our internal bonding tests. We hope these bonding results will be similar to the results found in your factory, and we will work with you to continually improve our specifications to ensure that this is accomplished. 

You will notice that these shoe uppers have a backing mesh. This was done in an effort to improve the efficiency of our process and to potentially help the shoe assembly process; however, this backing mesh is not required. The flat samples that were sent alongside the uppers contain no mesh. 

BOX 1: Samples Sent to the Factory 

This box contains four ‘Bonding 1’ shoe uppers (2 pairs), two ‘Bonding 2’ shoe uppers (1 pair), and two ‘Bonding 3’ shoe uppers [8 total samples].  


BOX 2: Samples Sent to Germany 

This box contains a ‘Bonding 1’ shoe upper & flat sheet, a ‘Bonding 2’ shoe uppers & flat sheet, and a ‘Bonding 3’ shoe upper & flat sheet [6 total samples]. 

SAMPLE DESCRIPTION 

Bonding 1 / Lightspeed: These samples were made with one of Simplifyber signature formulations, which is suitable for soft, lightweight, and flexible materials. They were treated with a waterborne synthetic polyurethane-based coating that delivers hydrolysis resistance, high elongation, good adhesion to a plastic matrix, and flexibility. 

Bonding 2 / Cloudhug: These samples were made with another signature formulation, which is suitable for lightweight flexible materials. They were treated with biobased & free from organic solvents polyurethane coating that delivers high flexibility & light fastness, as well as good abrasion resistance, mechanical stability, and film color, clarity, & gloss. 

Bonding 3 / Duralyte: This formulation is under development and has shown very good mechanical performance for light and flexible materials. They were also treated with our biobased polyurethane coating that delivers high flexibility & light fastness, as well as good abrasion resistance, mechanical stability, and film color, clarity, & gloss. 

Internal Bonding Test 

The images in Figure 1, show our uppers bonded, using Barge shoe cement, to both a rubber & EVA sole. 

Figure 1: Uppers bonded to Rubber and EVA soles. 

Figure 2 shows the setup and results of our internal bonding tests on these ‘new’ samples. We collected the bonding values of 6 areas along the uppers-sole interface. One test was done on a rubber sole and two tests were performed on an EVA sole. Additionally, we performed one test using the previous ‘old’ samples sent to the factory earlier this year, achieving similar results to the factory. One can see a >3x improvement in the average bonding strength (N/cm) of our new samples compared to the old samples.  

Figure 2: Results of Internal Bonding Tests


FEBRUARY 12, 2024 UPDATE:

We absolutely LOVE working with you, and we’re so excited to continue our engagement throughout 2024 and beyond. This latest sample kit, sent to you the week of February 12, 2024, is detailed below.

Sample 1 – Original 

  • Same formulation and finish sent to the factory on the 2nd batch of samples 

  • Properties: great mechanical performance, abrasion resistant, water resistant, low bonding properties, low flexibility. Available in other colors. 


Sample 2 – Flex1 

  • Same finish as sample 1, but different formulation 

  • Properties: good mechanical performance, abrasion resistant, water resistant, low bonding properties, improved flexibility. Available in other colors. 


Sample 3 - Bond1 

  • Different formulation & finish 

  • Properties: good mechanical performance, abrasion resistant, good bonding properties, improved gloss & flexibility. Available in other colors. 


Sample 4 - Bio1 

  • 100% bio-based 

  • Properties: good mechanical performance, abrasion resistant, low bonding properties, low flexibility. Available in other colors.