Halftone
Gradations
of tones achieved by varying sizes of printed dots in the printing of a
photographic reproduction.
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Hamper
A
container, usually round but may be elliptical or polygonal, larger at top
than at bottom, and of greater depth than width; having slatted sides or
staves, and solid or fabricated bottom, or having sides and bottom formed of
one continuous piece of material. Commonly used for shipping fruits and
vegetables.
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Handle
An
accessory attached to a container or part thereof for the purpose of holding
or carrying. A bail handle is made of sheet metal or wire and folds against
the container when not in use.
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Hazard analysis and critical
control points (HACCP)
System of
monitoring food safety and sanitary standards throughout a production,
packaging and distribution chain.
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Hazardous material (goods)
packaging
Certain
products which have been designated as potentially hazardous to people and
environment require special packaging, labelling, storage and handling as
prescribed by national and international regulations.
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Haze
A cloudy
or foggy appearance in a normally transparent plastic material.
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Head
The top
or bottom of a drum or barrel.
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Header label
A folded
printed label which fits over the mouth of a bag or sachet and is visible
from both sides. The label may be fixed to the bag by heat sealable coating
or by stapling. A hole is often punched in the header to permit rack hanging.
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Head space
The empty
space inside a container between the top surface of the product and the
inside upper surfaces of the container.
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Heat sealing
A method
of joining two or more compatible heat sealable surfaces or materials under
controlled conditions of temperature, pressure and dwell time.
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Heat-Seal Label
A label
made of paper or other material coated on one side with a heat-seal coating,
usually a thermoplastic resin, and characteristically difficult to remove
after application.
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Heat transfer labelling
Widely
known by the proprietary name Therimage, the label is transferred from a
plastic web to the pack by heating which activates an adhesive on its
surface. Used for high-value products in glass and plastic containers, but
superseded in many cases by transparent PS labels.
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Heavy-duty bag
Valve bag or open mouth bag generally of 25
kg weight, exceptionally above, made of thick polyethylene
film or og woven polypropylene fibers web
or of multiply Kraft paper, used for industrial packaging of diverse food and
non foof products in granular or powder form.
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Heavy Metals
Metallic elements of relatively high atomic
weight that, upon exposure, tend to collect in specific body organs and at
high levels are known to be toxic. Historically, lead solders were used to
seal metal can seams and most printing ink pigments were derived from
compounds containing heavy metals such as lead, arsenic, cadmium, mercury,
selenium, barium, chromium and antimony.
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Heel
The lower
portion of a glass or plastic container, starting with the bearing surface
of the bottom and including a small portion of the lower side-wall.
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Hermetic seal
An
airtight seal.
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Hessian
Term
applied to any coarse fabric used for
sacking; called burlap in North
America.
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Hilo
Also
called hi-lo. Double-wall corrugated board combining both A-flutes and
B-flutes.
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Hinged lid
A
container closure which is attached to the container by a flexible or bending
joint. The hinge can be a separate unit or can be an integral part of the
container.
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High density polyethylene
(HDPE)
Polyethylene
resin whose density exceeds 0.940 g/cm3.
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High-frequency (HF) welding
See: Electronic sealing.
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Hogshead
A large
wooden barrel, usually of more than 250 l (60 gallon) capacity.
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Hologram
Three-dimensional
printing that presents differing images depending on the angle from which it
is viewed. Used as a tamper evident feature on packaging as it is difficult
to reproduce or repair.
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Honeycomb board
A board
with its core structure consisting of a mesh or web with multiple cavities
laminated perpendicular — at right angles — to the facing. Exists in
different thicknesses. Used as a cushioning material and filler.
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Hot dip
Traditional
process for coating both sides of a steel sheet with commercially pure tin to
produce tinplate. The amount of tin coating on each side of the sheet can be varied to meet performance
requirements. Largely superseded by electrolytic coating that applies a thiner layer of tin.
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Hot melt
An adhesive or coating based on thermoplastic polymer generally
modified with resins or waxes, which is solid at room temperature. It is
heated to fluidity at the time of application, and is normally quick setting
as it cools.
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Hot-stamping
A
decorating operation by which a design is transferred from a roll of thin
aluminium foil to a surface by means of impressing it with heated metal dies.
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Humidity cabinet
A box or
room constructed with a conditioning device used to maintain a specified
relative humidity at a specified temperature. Used in testing packages for
their moisture resistance and barrier properties.
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Hydrophilic
Having a
strong affinity for water.
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Hydrophobic
Lacking
affinity for water, but usually attracting oily materials.
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Hygrometer
A device
for measuring relative humidity.
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Hygroscopic
Material
that absorbs water.
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