Two-shot solution speeds production

Problem: A new product to help premature infants feed required manual assembly, hampering ramp-up of production. 

Solution: Further developments in mold and product design allowed the part to be molded as a single unit. 

By Karen Hanna 

The nearest neonatal intensive care unit (NICU) to molder Silcotech is just minutes away. But the connection between care for the smallest newborn babies and the liquid-silicone-rubber (LSR) plant in Bolton, Ontario, is so much closer.    

Silcotech’s painstaking development of a sophisticated mold is at the heart of a new molding process for a kit that will help provide nutrition to some of the most vulnerable infants, including preemies.

Designed to overcome a variety of challenges, including some babies’ difficulty with feeding, pain experienced by nursing mothers and low milk quantity, the Neotech Bridge from Neotech Products includes a variety of sizes of tubes that allow new moms to control the volume and flow of supplemental milk. The device simulates breastfeeding and helps infants begin nursing at a time when they might be struggling with the process, or their mother's natural milk production is less than adequate.  

Silcotech worked on the project for four years, alongside Neotech, a Valencia, Calif.-based brand owner of a variety of medical devices for neonatal and pediatric intensive-care units, which bought rights to the product from its inventors. Together, they have turned the idea into a high-volume product that’s being marketed to hospitals, as well as retail customers.  

Silcotech has been developing and making products for feeding babies for years.  

“It's rewarding to solve these kinds of problems,” said Michael Maloney,. “If you read about the complexity of what breastfeeding means to a mother and how complicated it actually can be — in some cases, for some, far more complicated than for others. And the ability to supplementally feed during the evolution of the development of breast milk for the mom is pretty critical.”  

Ramping up production 

Integrating tubing into the cup that is positioned on users’ chests represented the biggest challenge to making the Bridge, said Dan Morris, business development manager at Silcotech. At first, the company manufactured the components separately and glued them together.  

Customer feedback supported the project, propelling Silcotech to advance production process so manual labor wouldn’t be required. 

To meet demand for the Bridge, the company had to go from 105-class molds to 103-class molds and, finally, to 101-class molds — as it and Neotech adjusted projections, from producing prototypes to hitting manufacturing levels of 500,000 parts to 1 million parts, respectively.  

“It started from handmaking prototypes to handmaking parts to a new tool built — there was an elaborate progression of technology and advanced manufacturing to get the product where it is today,” Morris said. “When it comes to the mold, the technology is in the delivery of the silicone.” 

According to Maloney, controlling how LSR spreads out over a second shot requires finesse. 

"When you're running a silicone over a silicone, the ability of the second shot to be restrained by the silicone that you're running it over is delicate. You need to manage cavity pressures to a very low level, so that you're not bleeding or leaking around the part,” he said.

“In the case of silicone, the pressures during injection can actually just drive the material out of the way, and all of a sudden, you no longer have the material constrained in the geometric shape that you're targeting.” 

But with decades of experience with LSR, Silcotech was up to the task. The plant, which employs 120-plus people, offers a range of services, including product development, mold making, prototyping, mass production and multi-shot silicone molding. 

Maloney said medical products make up about 80 percent of the work performed at the plant, which has 30 injection molding machines with clamping forces ranging from 25 tons to 300 tons. All are Arburgs.

“As a company, we have systems in place to help designers and inventors develop products. ... “ he said. “As we iterate through the product development, we can get to a point that we're comfortable that this system or device or development is functionally acceptable. We'll move then on to sort of bridge tooling, where we'll [have] hundreds of thousands of pieces to really do a wider study, market study, on performance of the device and validation of the device and validation of processes, before we move into high-volume production." 

The company worked to develop a two-cavity overmolding process in which the Bridge tubing was sealed during injection molding.  

“Silcotech leveraged its knowledge of creating hollow spaces in silicone parts as well as two-shot molding technologies to start the design of the ultimate molding systems,” Morris said.  

Key to the process — as well as Silcotech’s success with other LSR parts — is the company’s portfolio of proprietary equipment, developed over the years to handle the entire process, including mixing, metering and injection. The equipment can handle low speeds and very low pressures, and with the technologies, Silcotech is able to maintain control over the process, Maloney said.  

“We helped them make a silicone shield that had an integrated channel and tube for delivering formula into the nipple shield from an external syringe,” Morris said. “We developed a two-stage process at first, then a two-shot mold that molds the part with an open flap, then seals the flap with a second shot of silicone.” 

Bringing good ideas to life  

Offering a unique blend of anti-microbial, anti-inflammatory and immunoregulatory agents, breast milk is “more than nutrition — it is a vital component of medical care,” especially for premature and critically ill infants, according to a white paper written by Kathi Salley-Randall, a NICU nurse practitioner promoting the Bridge.  

“It decreases the risk for necrotizing enterocolitis, late-onset sepsis, lower respiratory tract infections, severe diarrhea and ear infections,” and babies who are able to get nutrition this way can leave the NICU sooner, she wrote. 

However, preemies often struggle at nursing, due to illness, separation from their mother in the hospital, developmental immaturity and other issues. Often, they’re fed by bottle, but this only further hampers the nursing process. 

The Bridge offer a transition to breastfeeding, especially for medically fragile babies.

Designed for ease of use, the Bridge can provide colostrum, expressed milk, fortified human milk or formula to babies. It has a silicone cover that offers babies an experience similar to drinking from a bottle. Unlike other breastfeeding assistance systems, it requires no tape for setup.  

“With the Bridge,” Salley-Randall wrote, “parents of infants in the hospital can be empowered to overcome many of the common hurdles to establishing a positive and long-lasting breastfeeding relationship with their baby.”  

While the need for the Bridge is clear to the product’s developers, Maloney acknowledged Silcotech’s efforts in the development weren’t the first.  

With nearly 50 years in plastics and LSR product manufacturing, he said he realizes products often wither on the vine. 

“The one thing you need to learn is to be able to fail, and fail as fast as possible. Because the reality is that out of 10 projects that you take on in terms of a new product development, maybe one or two of them will survive,” he said. “That’s probably a good survival rate. It's not about the two successes; it's about the learning with the eight failures that really make a company what it is, because becoming more efficient, more effective, in trying to get to the two out of 10 is pretty crucial.” 

Maloney said his company works with brand owners and customers closely to carry their ideas across the finish line. Molding their products is just one aspect of the process.  

“A lot of people have worked on programs like this, I'm sure, and they may have fallen into the 80 percent category, but we're fortunate that we've fallen into the 20 percent, but I can assure you that there were many attempts that didn't fall into the 20 percent to solve specifically this problem.” 

Seeing ideas like the Bridge come to fruition gives him special satisfaction — knowing the difference it will make for babies and their families.  

He believes the Bridge will have a positive impact.  

“I think in the medical device space, it's really kind of what drives us,” he said.