Marden Edwards Journal

Red Diamond Inc., from Birmingham, Alabama, USA has just placed an order for their second Marden Edwards S4B100FF fully automatic overwrapping machine.

Red Diamond, founded in 1906, is one of the three oldest family owned and run tea and coffee companies in the USA. It is dedicated to providing the highest quality teas and coffees to restaurants, hotels, offices, hospitals and homes across the Southeast USA.

The first Marden Edwards S4B100FF was purchased in November 2006 for over wrapping the 24, 48 and 100 count cartons of tea bags. The first reason for purchasing the new machine was to replace an existing overwrapper which was proving expensive and difficult to maintain. The second reason as to dramatically improve the appearance of the overwrap.

Red Diamond’s Joe George, Vice President Manufacturing, who was responsible for purchasing the Marden Edwards machines, said “I have been very pleased with the simplicity of operation of the Marden Edwards machine. It runs all our different sizes very efficiently and the quality of the wrap has been excellent. As our production volumes have increased it was an easy decision to buy another one”

The S4B100FF overwrapper is able to run all overwrap films, including traditional polypropylene and cellophane as well as the new biodegradable cornstarch based films. Marden Edwards has produced over 8,500 machines and all are still supported for spares and service.

Intraocular lenses used in eye surgery are the latest in a line of surgical items now benefiting from the protection and convenience afforded by overwrapping, following the installation of a Marden Edwards overwrapper by lens manufacturer Rayner.Traditionally these lenses have been packed into a carton and distributed to the surgeon for use in the operating theatre. However, the increasing demand for tamper evidence and proof of integrity led Rayner to take the decision to wrap the boxes in of lenses in plastic film at the point of production. For several reasons overwrap was selected as the preferred method of wrapping. For one thing there is little heat used in the wrapping process, reducing the risk of any heat damage to the acrylic lens inside the carton. In addition, the wrap retains a near hermetic seal until the moment of opening and it is possible to incorporate a tear strip with extended tab, enabling the cartons to be opened easily and quickly in the operating theatre.The machine chosen by Rayner has been newly introduced by Marden Edwards this year and is a cost effective entry level overwrapping machine that bridges the gap between basic shrinkwrapping systems and high speed overwrappers. It is simple to use and provides a high quality wrap over a wide range of carton sizes.Other surgical products overwrapped using Marden Edwards machinery include scalpels, syringes, hip replacement joints, colostomy bags and sutures all of which benefit from the integrity and ease of opening that overwrapping provides.

Tony O’Connor at Rayner says, “We researched the market for overwrapping machines and made contact with a number of suppliers. The price and performance of the Marden Edwards met our budgetary needs and meant that we could purchase a new machine with a full guarantee instead of having to settle for a second hand system.”

The short answer is an un-reserved “Yes”!. However, it is worth examining what constitutes an environmentally friendly wrapping film.

For many years the standard for over wrapping film has been BOPP, or Biaxially Orientated PolyPropylene. BOPP is manufactured from an oil based polymer and so is not biodegradable. Where waste is incinerated, BOPP film contained within the waste does act as a fuel and so improves combustion. BOPP does provide excellent clarity, barrier and strength properties at an economic price. The Exxon OPP website provides more information regarding the properties and applications for BOPP films.

However, as already explained in a previous Marden Edwards Journal article, “Overwrapping films come full circle”, cellophane used to be the material of choice for wrapping from 1912 (when cellophane was invented) onwards. Cellophane was made from cellulose, which is wood pulp, and this is inherently biodegradable. With the advent of a greater environmental consciousness, there is now a renewed interest in “green” and “environmentally friendly” wrapping materials and machines.

“Tuck and Fold” over wrapping has always been an environmentally friendly method of wrapping when compared to Polyolefin shrinkwrap. For shrinkwrap to produce a tight finish, the film requires a high shrink property when heat is applied. This results in high energy shrink tunnels being required for all over heating compared to overwrap’s requirement for localised concentrated heat to produce the lateral and end seals.

All Marden Edwards overwrappers are able to run with heat sealable paper with the paper being pre-trated with glue in the areas of the seals during the converting process. In addition, the KAP range of overwrappers can apply glue to uncoated paper during the wrapping process producing the equivalent of a paper casepack. However, wrapping with paper does not provide visibility of the product and for this only film will do.

Today, there are two main competing biodegradable types of film suitable for overwrapping – those that are manufactured from cellulose, such as Natureflex manufactured by Innovia and those made from PLA (polylactic acid) such as the Biophan film manufacture by Treofan. Whereas Natureflex is wood pulp based, Biophan is based on corn starch processed into a polymer by Natureworks.

Although predominantly designed as a replacement for Polyethylene (PE) Ecofilm from Cortec can run on Marden Edwards overwrappers producing a wrap suitable for transit and distribution multipacks.

The bio-degradable abilities of these products can be seen by this photograph of a biodegradable plastic cup. It is important to note that for composting to occur a high temperature needs to be maintained over a period of time.

In terms of true ec0-friendliness the debate has intensified further. The Friends of the Earth organisation has questioned whether producing fuel, and by implication bio polymer, from crops does in fact increase carbon released into the atmosphere by promoting the destruction of wetlands and forests. It argues that better management is required to monitor the complete lifecycle effect. The feedstock required for cellophane, on the other hand, comes from wood pulp which can be derived from existing, sustainable forestry.

With regards to Marden Edwards machinery, the positive gripper film draw mechanism has always been extremely tolerant to many different types of film and paper. It has the ability to handle very thin (17 micron or less), very thick (greater than 60 micron), very stiff (such as PVC) and very floppy (such as Polyethylene) films. In addition, the other strength has been the ability to run poorly wound and poorly stored films.

Because of Marden Edwards’ near 50 years of over wrapping expertise, BOPP, cellophane based and the new corn starch based films run equally well across the entire Marden Edwards range. It is noticeable that for some industries, such as Tea production, the shift to bio-degradable films is accelerating. Both new and old Marden Edwards machines are today running these films with no special adaptation.

Wedgewood Handmade Confectionery of South Africa has recently installed a new Marden Edwards S4B100FF automatic overwrapping machine. Wedgewood is a young family company which starting producing high quality nougat biscuit bars in the family kitchen eight years ago. Originally, the naked nougat bars were wrapped by hand but as the business became more successful and demand grew a fully automated system was required.

With the help of Marden Edwards’ South African agent, Pakmatic, a specification was drawn up for a machine to wrap at 35 cycles per minute and to be able to cope with the variations in product size that can be expected with a hand made product. Utilising their own expert knowledge of producing nougat, Wedgewood manufactured the product feeding system themselves which they integrated into the overwrapper.

Based on extensive experience of over wrapping chocolates and confectionery, as well as other “naked” food products such as cake, Marden Edwards provided a machine suited to the sticky and irregular shaped nature of nougat. Of particular concern was the nuts within the nougat bar, which often protruded from the bar itself.

John Walter, Project Engineer for Wedgewood, said “I liked the openness and simplicity of the Marden Edwards over wrapping system. It enabled me to easily link the machine into my production line. I found the technical support and assistance at Marden Edwards very helpful as we commissioned the system and went from factory trials to full scale production. The system is able to cope with any pack size variation but still produces a really high quality wrap.”

The flexibility of the machine has proved helpful in other ways. A cartonned, presentation five bar multipack is also being wrapped on the same machine when it is not required for the individual bars.