Our Manufactured Product Range

Diverse modern raw materials (polymers and additives) together with 35 years of manufacturing techniques and product development mean that Derek Lambert Polythene can extrude a very broad range of high quality film with properties to match most applications. We do sell our extruded film directly, but most is internally converted into bags, sheets and covers, often with added treatments and printing.

Polythene film is usually extruded from a mix of Low Density polymer (LDPE) and a Linear Low Density Polymer (LLDPE), but film characteristics can vary considerably with the raw polymer specification & quality, mix percentages, additives, extruder size and production techniques.

The mass-cost of raw material relates directly to the selling price and so using advanced polymers to produce thinner, better film capable of higher performance can reduce costs substantially. Equally, the correct use of additives and utilisation of our manufacturing techniques can also significantly impact the film quality and the gauge thickness required.

Standard Gusseted Range
Units mm in mm in μm g
FILM All 2900 114 4800 189 25-375 100-1500
SHEET Single 2900 114 4800 189 25-375 100-1500
Centrefold 5800 228 9600 378 25-375 100-1500
BAGS Bottom Weld 2900 114 4800 189 25-375 100-1500
Side Weld No width Limit. Max Depth = 2900mm. 25-376 100-1501
COVERS Bottom Weld 5800 228 9600 378 25-375 100-1500
Side Weld No width Limit. Max Depth = 2900mm. 25-376 100-1501

Polythene Films

Standard layflat tube or Gusseted – continuous rolls of polythene film (Lay Flat Tube/LFT)

Our film extrusions are the basic high quality building blocks for all our products and can be simple combinations or sophisticated mixes of raw polymer and additives to cover a wide range of functional, visual and practical requirements.

We supply our extruded film directly for conversion or to cut-off random lengths, but most is internally converted into bags, sheets and covers, often with added treatments and printing.

General Film Features and Types

Prime Material Food Grade
High Strength Applications
Heat-Shrink Applications
Re-granulated General Purpose

Polythene Sheet

Standard Layflat Tube or Gusseted – edge trimmed or slit. Rolls perforated to length for tear-off or single sheets in boxes.

Often used  as liners, barriers and membranes, sheets are used to protect products or prevent migration of unwanted liquids and gases. Corrosion preventing additives, colours and strong polymer mixes can be common. Not usually manufactured shrink film.

General Sheet Types

Single wound (single width sheet)
Centrefold (double width sheet)
Multi-fold (Gusseted single or double width sheet)

Polythene Bags

Standard Layflat Tube or Gusseted –  rolls perforated and welded to length for tear-off or boxed as single bags.

Bags generate the broadest range of applications and combination of materials to match them. Our long experience means that we have seen and produced bags for most applications and can confidently adjust mixes or methods if requirements change.

General applications can request:

  • Food Grade
  • High Clarity
  • Easy To Open
  • Easy To Apply
  • High Strength/Joint
  • Breathable
  • Sun Resistant
  • High Friction

Using the correct product mix and manufacturing techniques are crucial experience leading to reliable, functional products.

General Bag Features/Types/Variations

Standard or Gusseted Layflat Tube
Bottom Weld
Side Weld (Side Slit)
Double Weld (Very Heavy Duty)

Polythene Covers

Standard layflat tube or Gusseted,  usually rolls perforated and welded to length for tear-off or can be boxed single covers.

Covers are a usually a thicker type of bag, usually made to go over and protect a pallet of products and are frequently called Pallet-Covers.

The film can be shrink or non-shrink type depending on the application with the majority being heat-gun shrunk down to provide a solid pack. Various additives can be added to protect against the sun and rain or to help grip the product being covered  (Antislip).

From light covers to heavy duty stone covers, there are many variations to match each application.

General Features/Types/Variations

Standard Or Gusseted Layflat Tube
Bottom Weld
Side Weld


Colours (Opaque's and tints) Standard and special colours available
Slip Allows bags/covers to open and slide over packed goods more easily
AntiSlip Grips products being covered - good for shrink covers in particular.
UVI (Ultraviolet protection) Prolongs the life of polythene
Biodegradable Breaks down the polythene after a period (% used)
Non-Fusion Stops the plastic sticking together, but can also make bag welding difficult
AntiStatic Reduces static, often required when used in textile processes.
VCI Anti-Rust/Corrosion inhibitor


Common Product Conversion Options (Please ask if not listed)

Perforated Film (all over perforations)
Slitting And Cut Outs
Edge Trimming

Logos and Printing

Film Surface Treatment (better print and life)
Large Or Small Logos
Warning Labels


On Rolls – Tear Off Bags, Sheets Or Covers
In Boxes – Separate Bags, Sheets Or Covers (large or small)


Layflat Tube Basic extruded polythene 'bubble' is flattened and rolled up
Gusseted Layflat tube with sides tucked in to allow larger width films to be rolled
Multifold Same as Gusseted
Single wound Layflat Tube cut or slit at both edges for separating and winding up onto two rolls
Centrefold Layflat tube with one-side edge trimmed or slit gives a double width sheet
Side-Weld Tube edge-trim/slit down one side and welded/perforated at the top and bottom.