Tape come in various lengths, widths, and thicknesses, colors and adhesive systems. For the purposes of this discussion we will focus on Carton Sealing Tape and various specialty tapes.
CARTON SEALING TAPE
Carton Sealing Tape is a pressure-sensitive tape used for closing or sealing corrugated fiber board boxes. It consists of a pressure-sensitive adhesive coated onto a backing material which is usually a polypropylene or polyester film which is oriented to have strength in both the long (machine) direction and the cross direction.
Carton sealing tapes are a packing tape used in a variety of environments and require characteristics to suit the application. The film carrier may be polypropylene, PVC; or it may be paper. Carton sealing packing tapes may have an acrylic, hot melt rubber, or natural rubber adhesive system; and the typical film backing may be clear, tan, or any number of colors, in the case of PVC. Carton sealing tapes are typically 55 yards or 110 yard rolls. Machine length rolls can range from 1000-2000 yards in length. Also, the width may be 2, 3, 4 or 6 inches. All of these sizes are available in metric form that is roughly equivalent. These packing tapes are offered in many different thicknesses. Economy tapes may be less than 1.5 mils thick while heavy duty carton sealing tapes are over 3 mils thick.
Carton sealing tapes are generally used for packing and sealing boxes. Corrugated cardboard boxes sealed with the proper carton sealing tape maintain their integrity and hold their contents securely. Since carton sealing tapes are used for sealing boxes, the adhesive system, backing strength and other physical properties must perform to the required task. Consequently, there are many grades and varieties of carton sealing tape. Recycled corrugated cardboard may require an altogether different carton sealing tape than cardboard that is not recycled.
The tape is most often used as a closure for regular slotted containers (RSCs). A “single strip” or “center seam” closure is applied over the center seams of a box extending 50–75 mm (2–3 inches) onto the end panels.
The tape can be used as a “six-strip” closure or “H-seal” by applying cross strips on the ends of the box. This is used when a relatively weak tape is used or when extra box reinforcement is needed. This method also seals the box to help keep contaminants out.
Carton sealing tapes have three principal adhesive systems:
- natural rubber
- hot melt
- acrylic adhesive
The backing is typically clear (sometimes the customer prefers tan) biaxially oriented polypropylene (“BOPP”) film, but some paper tapes are used for carton sealing.
- Higher end Kraft flatback paper tapes have a silicone release coating on the back of the paper while the adhesive system is typically synthetic rubber based. Lower end water activated paper tapes are slowly being phased out as they are messy and difficult to apply. Paper tapes offer flexibility for sealing carton corners, edges and irregular surfaces, and they are environmentally safe since they may be biodegradable and recyclable.
- Hot melt adhesive systems have better quick stick bonding to corrugated paperboard.
- Acrylic adhesive systems require more time to set up and form a bond, but acrylic adhesives have better long lasting adhesive properties.
- Carton sealing tapes may be applied by hand with hand held dispensers, or they may be machine applied.
- In facilities that use significant amounts of carton sealing tape, it may be desirable to use a carton sealing tape with a quiet unwind so as to reduce noise.
- Both paper and BOPP carton sealing tapes may be printed and customized with a logo, corporate information or specific color. Also, certain carton sealing tapes are tamper evident and will signal when a package has been opened or tampered with.
- Carton sealing tapes are available in different widths and lengths, and heavy-duty carton sealing tapes, general purpose, or economy grade products may be held in stock because of the high volume and broad application for these products.
- In addition to different strengths and thicknesses, the shear properties of carton sealing tapes may also vary.
|Acrylic/Acrylate||Acrylic films are plastic or thermoplastic resin films manufactured using polymethyl methacrylate (PMMA) or polymethyl-2-methylpropanoate. PMMA resins are the result of polymerization of acrylic acid derivatives or other acrylate compounds such as esters of acrylic acid, methacrylic acid, acrylonitrile and their copolymers. Acrylic films have good optical properties (clarity) and are UV stable. Plexiglas® (Altofina Chemicals, Inc.) is a common acrylic sheet and film material.|
|Cloth||Cloth materials like cotton can be used as the carrier material to improve tensile strength, heat resistance, and electrical resistance.|
|Glass/fiberglass||These are similar to cloth carriers, but are reinforced with glass or fiberglass particles to enhance heat resistance to over 300° F.|
|Fluoropolymer||A fluoropolymer backing will provide excellent chemical resistance, as well as water and stain resilience. The inert nature of these types of carriers prevents items from sticking to the carrier. Polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF) are common carriers for adhesive tapes.|
|Foam||Adhesive-coated polyolefin foams include an adhesive that is protected by a liner in the form of a tape, film or laminate.|
|Metal foil||Metal foil tapes offer high reflectivity and heat resistance. They commonly have aluminum, aluminum-reinforced, or lead backings.|
|PET/polyester||Polyethylene terephthalate/polyester carriers have high resistance to solvents and have good aging and clarity characteristics.|
|Paper||Paper backings are suitable for short-term packing solutions, as they are weak in construction|
|Plastic/polymer||Adhesive-coated polyolefin foams include an adhesive that is protected by a liner in the form of a tape, film or laminate.|
|Polyimide (e.g. Kapton®)||Polyimide film maintains excellent physical, mechanical, chemical and electrical properties over a wide range of physical environments. Kapton® tape is made of polyimide film and a heat-resistant, silicone adhesive. Kapton is a registered trademark of DuPont Teijin Films. Polyimide films are very useful substrates for the manufacture of flexible circuit materials.|
|PVC/vinyl||By using a vinyl carrier, the packaging tape has enhanced biological and chemical invulnerability, as well as more flexible workability. PVC is also relatively cheap.|
|Rubber||Many rubber-backed tapes are self-adhering and can create a water-tight bond. These tapes have high thermal stability and elastic deformation, but can be chemically susceptible|
|Silicone||These tapes will use a solid, silicone backing in the form of a tape, film, or laminate. They provide tight, void-free and moisture resistant electric insulation. This is optimal for splicing and stress cones.|
|Water Activated||Water-activated tapes are starch or glue adhesives on a reinforced paper carrier. The tape is moistened to initiate the bond and dries to a hardened seal.|
Common Types of Packaging Tape/Film
|Parcel tape, colloquially box tape or packing tape, is a simple, medium-strength tape designed for sealing corrugated fiberboard seams. It is widely used in package delivery and mail services, as well as general sealing and enclosing. Brown-colored and translucent tape is most common, but other designs with messages or patterns are manufactured. Adhesion is achieved by pressure sensitive or water-activated designs on a paper, polymer, or acrylic carrier.|
|Filament Tape: (a.k.a strapping tape) Is a high-strength, pressure adhesive type of packaging tape, and is most often used for bundling items, pallet stacking, and seam sealing. The carrier is frequently polyester or polypropylene and fiberglass, providing the capability to withhold several hundred pounds of pressure. Multiple pieces of tape in a cross-seam orientation can significantly increase box strength.|
|Light-Duty: Packaging tape is used for simple sealing and enclosing operations. It typically has a rubber resin, pressure sensitive, or acrylic adhesive. Easy to dispense and handle, some durability and strength have been sacrificed for a consumer-friendly design.|
|Security: Packaging tape is applied to containers to provide a tamper-evident seal. This is common for medicinal and nutritional products. It is usually a secondary form of packaging.|
|Corrosion Inhibiting: packaging films and wraps are coated with rust-inhibiting chemicals that migrate to packaged metal components. This helps prevent oxidation during long periods of transportation or disuse. These are easy solutions to rust prevention and are non-toxic.|
PACKAGING TAPE SPECIFICATIONS
For tapes, there are two important geometrical aspects to consider, width and thickness. Length is unimportant because this is determined by the user at the point of application.
- Width: Is the measurement across predetermined edges of the tape. Tapes can be cut by the customer to smaller widths.
- Thickness: Is the distance between the two, flattened surfaces of the tape (carrier and adhesive). It is usually expressed in mils or thousandths of an inch and is measured under pressure with a gauge.
- Wraps: Are produced in rolls or large cuts, which are then resized or shrunk by the consumer.
- Tensile Strength: is the maximum load the tape can withstand. Packaging tape strength ranges from a few ounces to hundreds of pounds and is important for keeping items sealed.
- Peel Strength: is the amount of force needed to separate two bonded surfaces.
- Temperature Resistance: is the amount of heat the tape can be subjected to without compromising the tape’s performance. Packaging tape typically does not have enhanced temperature properties, and packaging film has a molecular structure that aligns and tightens when heated.
- Abrasion Resistance: is the level of scratch resistance and ruggedness of the tape.
- Transparent: products allow the transmission of light. A tape is rated as transparent if 10-point type can be read easily when the tape is applied directly over it.
- Once applied, products become permanently bonded to the substrate.
- Weather resistant: products are suitable for outdoor use and resistant to ultraviolet (UV) light, cold, heat, water or other weather conditions.
- Safety: film and tape products are used for flagging or as barricade tape. Reflective tapes are often used in safety applications. Multi-colored tapes can be used to differentiate seams.
Federal mail organizations and private delivery services often dictate suitable types of packaging tape. Pressure sensitive, water adhesive, and rubber resin tapes that are brown or clear may be the only acceptable taping options. Confer with each shipping carrier.
ATSM has several standards related to the manufacture of quality box sealing tapes and films. The U.S. Federal Government has internal regulations for the use of quality packing tapes and vinyl’s. The Pressure Sensitive Tape Council is a trade association that works with ATSM to establish North American quality guidelines for adhesive tapes, including packaging tape. ISO compiles quality standards through its series on adhesives.
PACKING TAPE PRODUCTION
Packing Tape Applications
As stated, the most extensive use of packaging tape is mailing and shipping, as well as product sealing. These tapes are removable and are recommended to be applied to box seams in an ‘H’ pattern. Packaging tape is also designed to provide visual indication when package has been tampered with, including attempts to tape over the original seal. Strapping tape is particularly useful for bundling pipes and tools. Individually wrapped foods, cigarettes, and even homes are commonly placed in shrink wrap to isolate the items from decay and/or water.
HOT MELT PACKAGING TAPE VS ACRYLIC PACKAGING TAPE: WHAT’S THE ACTUAL DIFFERENCE?
Choosing the correct packaging tape for your application is essential to the presentation, protection, and security of your product. The diagram below will help you to understand which tape application is best for your packaging needs:
HOT MELT PACKING TAPE
Hot melt packaging tape has a higher adhesive character, making it ideal boxes with high amounts of recycled content.
Hot melt tapes exhibit significantly better adhesive properties when compared to an acrylic packaging tape. They possess superior holding power and tensile strength with a quick tack. A hot melt tape is ideal for applications involving machine applied tapes, overstuffed boxes, or those with a high degree of recycled content. They perform well in temperatures ranging from 45*F to 120*F.
- Can be purchased in both hand-grade rolls and machine-grade rolls
- Provides easy unwind, as well as consistent and reliable seals
- Higher level of flexibility allows for better performance under constant strain or stress
- Available in clear, tan, and colored rolls; sold in “by the case” quantities
- Ideal examples of usage: shipping, short-term storage, box/carton sealing, boxes/cartons with high recycled content
ACRYLIC PACKAGING TAPE
Acrylic packaging tape is ideal for long-term storage because it resists yellowing because of oxidation. Acrylic packaging tapes, on the other hand, offer a wider temperature range than that of the hot melt tapes, ranging from 32*F to 140*F. An acrylic tape is ideal for applications that involve low and/or high humidity conditions, as well as long term storage. Acrylic tapes also have a stronger resistance to oxidation, allowing it to be uninfluenced by exposure to sunlight, meaning it won’t yellow like hot melt packaging tape does.
- Can only be purchased in hand-grade rolls
- Often considered more of an “economy grade” packaging tape
- Available in clear, tan, and colored rolls; sold in “by the case” quantities
Examples of usage: Long-term storage in varying temperatures, lightweight carton sealing/carton closing.
- Hot melt tapes offer exceptional adhesion strength, flexibility, and performs well in varying applications.
- Acrylic tapes are ideal for packaging applications involving extreme temperatures, such as refrigeration, and for sealing boxes that will be warehoused over a long period of time.
- Hot melt tapes can yellow with age, whereas an acrylic tape is less likely to yellow over time.
- Machine grade hot melt tapes generally perform more reliably than machine grade acrylic tapes.
- Both acrylic packaging tape and hot melt carton sealing tapes are comparable in price, offering both premium and economical grades.