ABC of glass


The world of glass from A to Z


Property of absorbing a proportion of the radiation or energy radiation through the glass 

Acrylic glass

Cast or extruded acrylic-based "plastic glass". Mechanically workable (sawing, drilling, milling etc.), yellowed under UV radiation, has a low surface hardness (sensitive to scratches).

Adhesive bonding

Joining glass and metal using suitable adhesives

Alarm glass ESG (Toughened safety glass)

Toughened safety glass with burnt-in, electrically conductive alarm loop. In case of glass breakage, the current is interrupted and an alarm is triggered.

Alarm glass VSG (Laminated safety glass)

Laminated safety glass with alarm wires inserted, which trigger an alarm if damaged


Generic term for glass applications in ESG with metal fittings as doors, switches, air traps, etc.

Antique glass

Glass with irregular surface structure with streaks and bubbles

Antique mirror

Mirror with artificially generated aging phenomenon


Reduced reflection of the glass due to surface treatment

Anti-reflection coating

Reducing the reflection of the glass by etching or coating

Anti-reflective glass

Interference-optical anti-reflective glass with light reflection < 1 % (anti-reflective coating on both sides) e.g. Luxar "Classic".


Reduces the risk of slipping by treating the surface


Abbreviation from the sealant sector: ethylene propylene terpolymer rubber (old abbreviation for EPDM)

Armoured glass

A previously used general term for laminated safety glass made of more than two panes, which offers a high level of protection against shots and impacts in particular.

Automotive glass

Generic term for all glass used in vehicle construction

Ball proof

Tested ball throwing safety


Deformation (usually in a heating process)

Bevel grinding

Grinding of a bevelled edge, angle 45° or greater


Prevents the penetration of thrown or flung objects.

Borosilicate glass

Fire-resistant, high thermal shock resistant glass

Brass glazing

Kuster glazing made of small glasses which are joined together to form a glass pane by means of special brass profiles

Breakthrough resistant

The penetration of a glass is delayed (burglar-resistant)


The penetration of bullets is prevented (bulletproof)

Burglar resistant

The penetration of a glass is delayed


Sandblasting of the glass surface and subsequent smoothing with hydrofluoric acid

Cast antique glass

Continuously rolled cast glass with imitated antique surface structure

Cathedral glass

White or coloured ornamental glass with a hammered surface

Chemical resistant

Resistant to acids and alkalis


Applying the silver layer to mirrors / Application of precious metal layers on float glass

Concrete glass

Pressed solid glass for structures that can be walked on and driven over

Corners knock

Blunting of the corners


Phasing of drilled glass holes


Prevents people from falling (e.g. on balustrades)

Crown glass

The crown is a mouth-blown glass. A blank pane is made by gripping the sheet by means of lead rods. Cast glass is also manufactured with the same designation.

Crystal glass

Frequently and commonly used term for mostly lead-containing, ground hollow glass with increased refractive index

Curved glass

Glass formed by a heat process by means of a form


Scribing with diamond or carbide wheels and subsequent breaking to form the so-called cutting edge

CVG Chemically toughened glass

Glass with higher flexural strength and thermal shock resistance, but in the fracture pattern similar to float glass

Dead weight

1 m² glass with 1 mm thickness weighs 2.5 kg

Drawing glass

Machine drawn window glass

Drawing strip

Possible drawing shafts from the drawing process with machine-drawn glass (lively surface)


Making holes


Suitable for driving on with vehicles


Baking of ceramic colours or glass enamel colours at temperatures above 600°C


Production of ornaments, lettering and decorations by mechanical surface treatment

ESG toughened safety glass

Prestressed float or cast glass with greatly increased impact and bending strength and resistance to thermal shock, which disintegrates into blunt-edged crumbs in the event of breakage

Etched glass

Glass with chemically produced matt whole or partial surface

Explosive effect inhibiting

Resistant to defined development of pressure waves in explosions

Extra white glass

White float glass without the typical green tint

Facet grinding

Grinding of a bevelled edge, angle less than 45

Flashed glass

Glass that consists of two or more layers, whereby a usually clear glass is covered (flashed over) with a light-scattering layer.

Fire polishing

Refinement of the glass surface ("polishing") by special heat treatment.


High resistance to thermal shock

Fire resistant glass

Tested and/or fire-policy approved glass


Fire resistant glass of the Glas Trösch Group

Flat glass

Generic term for all flat glasses such as plates, sheets and panes

Float glass

Glass produced by the float process (floating on liquid tin). Has two absolutely plane-parallel surfaces.

Frosted flashed glass

Two-layer glass with a colourless base layer and a milky opaque uniform coating layer

Frosted glass

Glass roughened by etching or sandblasting


Subcooled inorganic melt product with amorphous (non-crystalline) internal structure

Glass blocks

Two shells produced by the pressing process, which are joined together to form a hollow glass body

Glass breakage resistant

Increased resistance to glass breakage

Glass fittings

All types of fittings suitable for glass, such as door handles, hinges, locks, sliders, etc.

Glass holding systems

Special holding systems for glass constructions such as facades, canopies, etc.

Glass sealants

Sealing materials that are particularly suitable for glass

Glass stairs

Stair constructions with steps made of laminated safety glass

Goethe glass

Machine-drawn colourless window glass named after the old window glazing of the Goethehaus in Frankfurt. Used for the restoration of historic glazing.

Grinding oblique corners

Diagonal grinding of the corners

Grinding round corners

Grinding of corners with a certain radius


Resistant to hail grain fogging

Heating glass

Glass provided with resistance heating elements such as electrically conductive wires (laminated safety glass), printed electrical conductors or electrically conductive surface coatings

Heat protection glass

Glass with increased thermal insulation properties

Heat resistant

Non-sizzable, non-combustible, non-flammable


Insulating glass of the Glas Trösch Group


Break unmachined cutting edges at an angle of 45° to prevent injury

Highly hygienic

Easy to clean, no breeding ground for microorganisms

Hollow glassware

Generic term for glass containers of all kinds, e.g. bottles

Injury inhibiting

Limited risk of injury in the event of glass breakage

Insulating glass

A glazing element consisting of two or more glass panes separated by one or more air- or gas-filled spaces which are connected at the edges to be air-, gas- and moisture-proof.

No entry

No entry


Grind matt

Lead glass

Leaded glass for protection against X-rays

Lead glazing

Small pieces of glass joined together to form a sheet of glass by means of lead rods

Light scattering/diffusivity

Light is refracted and deflected, for example by an ornamental surface structure


Limited reflection of the glass

Low-reflective glass

Frosted picture glass that is only suitable if the image in question is at a short distance from the glass.

Not to be confused with the qualitatively superior anti-reflective picture glass Luxar "Classic".


Anti-reflective glass of the Glas Trösch Group


A tinted, drawn machine glass with a smooth surface on one side and a ribbed surface on the back side


Etching or sandblasting of glass surfaces

Milk glass

Translucent white opaque glass


Separation and cutting of mainly thick, mostly laminated safety glass using milling tools


Clear or coloured float glass sprayed with a silver layer and provided with a copper layer and a top coat

Mirror glass

Mechanically processed plane-parallel and surface-polished glass

Moisture Resistant

Does not absorb or release any moisture, thus no change of shape such as swelling, warping, shrinkage, discarding, etc.

Mouth blown glass

Special glass, mostly coloured, produced by the old glassmaker's blowpipes method.

Neo-antique glass

The neo-antique glass is a mouth-blown glass, which is produced according to traditional production methods. Not to be confused with machine-drawn neo-antique glass.

Noise insulation glass

Glass with increased soundproofing properties

Notch grinding

Grinding a trough-like notch on the glass surface for horizontal sliding of the glass in furniture or switch systems


Does not absorb and does not release odours

Opaque glass

Non-transparent glass, white or coloured in mass

Opal glass

Also opal flashed glass, light-diffusing glass with colourless or coloured base layer and opalescent flashing

Ornamental glass

Cast glass produced by the machine rolling process, colourless or coloured, with surfaces shaped in relief on one or both sides

Ornamental glass with wire

Cast glass with wire mesh insert and surface structure on one or both sides.


A solid-coloured float glass with heat-absorbing properties

Picture glass

Thin glass, reflective or anti-reflective, for the protection of image surfaces. The leading picture glass is Luxar "Classic"


Generic term for cast plastic glass


Cutting edge bright polished as straight edge with 45° phase or round or semicircular edge etc.

Polished wired glass

Flat, transparent, clear soda-lime glass with parallel and polished surfaces, produced by grinding and polishing the surfaces of wire ornamental glass. (see also product description for ornamental glass)

Polycarbonate glass

Extruded polycarbonate-based plastic glass, increased impact resistance

Pressed glass

Glass formed by a pressing process, such as the glass block


Refining process in which the glass is thermally or chemically brought into a system of constant stress distribution (compressive stress on the surface, tensile stress in the glass core).


Application of ink with different printing processes

Profiled building glass

A cast glass manufactured as U-profile by machine rolling with ornamentation on the outside.


Psi value is the linear heat transfer coefficient of the transition between frame-glass edge-glass. This value is included in the U-value calculation of the insulating glass and formulates the additional heat dissipation in the area of the edge seal. The Psi value depends on the insulating glass spacer material and the window frame material as well as the number of insulating glazings used (2 or 3-fold).

No entry

Raw glass

Cast glass, similar to cathedral glass, which can be produced in greater thicknesses

Raw mirror glass

A cast glass formed with smooth rollers with only slightly patterned surfaces, which was formerly used to produce mirror glass.


Natural reflections of the glass


Mechanical roughening of the glass surface with sand


Separation and cutting of mainly thick, mostly laminated safety glass using sawing tools


Hobby decorating of glass surfaces using appropriate scribing tools


Grouting of glass with special sealants

Security mirror

Covered toughened safety glass and laminated safety glass or acrylic and polycarbonate glass


In case of breakage the splinters are held together

Signal glass

Glass for light signals in road, rail and shipping traffic in the colours red, green, yellow and blue

Silk matted

Finely etched glass with diffuse and non-reflective reflection


Insulating glass of the Glas Trösch Group with at least one thermal insulation coating

Solar control glass

Glass that can perform sun protection functions (low g-value)

Spy mirror

Semi-transparent coated glass, which allows viewing from the dark to the bright side, but not vice versa

Stained glass

Cast, solid-colored, translucent, thick glass plate with lava structure


Solar control glass of the Glas Trösch Group

Surface refinement

Subsequent processing of the surface of flat glass by grinding, polishing, etching, sandblasting, etc.


Toughened safety glass with alarm function from the Glas Trösch Group


Screen-printed glass of the Glas Trösch Group


Toughened safety glass from the Glas Trösch Group


Curved glass of the Glas Trösch Group


Laminated safety glass of the Glas Trösch Group


Glass steps with support system and anti-slip strips from the Glas Trösch Group


Glass point holding system for single and multi-pane glass of the Glas Trösch Group


Light-diffusing, non-transparent glass element with glass-fibre fleece or glass-fibre spun between two glass panes

Thin glass

Categorie of glass usually thinner than 2 mm (not for building purposes)

Traffic mirrors

Curved mirrors used in road traffic


Light-transmissive, but not clear transparent


No restriction on viewing

Transparent inhibiting

Light-transmissive, but strongly reduced transparent

TVG Partly toughened glass

Glass with higher flexural strength and thermal shock resistance, but in the fracture pattern similar to float glass


In European standardization, all sizes are abbreviated on the basis of their English word names. This designates the heat transfer coefficients (U-value) as follows:

Ug - Glazing

Uf - Frame

Uw - Window

Ucw - Curtain Walling

VSG laminated safety glass

Consisting of at least two glass panes connected with at least one viscoplastic, highly tear-resistant PVB film (polyvinyl butyral)

Water jet cutting

Cutting of free forms, corner cut-outs, cut-outs and bores with water jet without post-processing of the matt edges

Window glass

Flat glass produced by mechanical drawing process

Wired glass

Cast glass with wire mesh insert with lower flexural strength than normal glass of comparable thickness.

Wire-mirror glass

Mechanically processed plane-parallel and surface-polished glass with wire mesh insert with lower flexural strength than normal glass of comparable thickness.

X-ray protection glass

Glass containing a high amount of lead with high absorbency for X-rays

No entry

No entry