WO2010134805A1

WO2010134805A1 - Light emitting concrete comprising photoluminescent pigment containing glass particles

Info

Publication number: WO2010134805A1
Application number: PCT/NL2010/050293
Authority: WO
Inventors: Gerard Willem De Bruijn
Original assignee: NEXT GENERATION BV
Current assignee: NEXT GENERATION BV
Priority date: 2009-05-18
Filing date: 2010-05-18
Publication date: 2010-11-25
Anticipated expiration: 2011-11-18
Also published as: NL1036967C2

Abstract

Method for making a product from concrete, which method comprises the introduction of small light-emitting glass pieces into the product made of concrete or their application to the surface of the product made of concrete, where the small glass pieces contain a light-emitting pigment, either by the introduction of a coating into which small luminescent glass pieces have been incorporated into the concrete or its application to the top layer of the concrete, with the aid of a resin, an adhesive, or a plastic of the type that adheres to the concrete, or by the insertion of the small light-emitting glass pieces into a mould by scattering them on the bottom of the mould and then pouring concrete over them, or by the application of the small glass pieces to the concrete in the form of a top layer, and by making the small glass pieces visible on the surface of the concrete, after which the concrete is further processed, smoothed down or otherwise treated, so that a product made of concrete is obtained that has a light-emitting surface, with small glass pieces comprising light-emitting pigments that can emit light in the dark.

Description

LIGHT EMITTING CONCRETE COMPRISING PHOTOLUMINESCENT PIGMENT CONTAINING GLASS PARTICLES

Technical field

The present invention relates to a method for making a product from concrete that contains light-emitting glass pieces comprising a light-emitting pigment. The present invention also relates to a product made of concrete that contains light-emitting glass pieces comprising a light-emitting pigment.

Summary of the invention

In one of its embodiments, the present invention provides a method for making a product from concrete according to Claim 1. This method comprises the introduction of small pieces of glass into a product made of concrete or their application to the surface of the product made of concrete, where the small glass pieces contain a light- emitting pigment, either by the introduction of a coating into which small luminescent glass pieces have been incorporated into the concrete or its application to the top layer of the concrete, with the aid of a resin, an adhesive, or a plastic of the type that adheres to the concrete, or by the insertion of the small light-emitting glass pieces into a mould by scattering them on the bottom of the mould and then pouring concrete over them, or by the application of the small glass pieces to the concrete in the form of a top layer, and by making the small glass pieces visible on the surface of the concrete, after which the concrete is further processed, smoothed down or otherwise treated, so that a product made of concrete is obtained that has a light-emitting surface, with small glass pieces comprising light-emitting pigments that can emit light in the dark.

In another embodiment of the method, the small pieces of glass are made visible by a procedure that includes a step in which the surface of the concrete is smoothed down.

In an alternative embodiment, the small pieces of glass are made visible by a procedure that includes a step in which the surface of the concrete is washed clean.

In an embodiment of the method, the product that is made of concrete and contains small light-emitting glass pieces is chosen from a group comprising brick-like blocks, paving stones, kerb-stones, internal walls, external walls, stairs, small posts, road direction markers, indicators, traffic items, safety items, warning items, plant boxes, containers, slabs, and obstacles ensuring road safety.

hi an embodiment of the method, the small light-emitting glass pieces are added to, dispersed in, applied to or on, or incorporated in or on the surface of the product made of concrete, with the aid of an adhesive, a layer of paint or another coating, or else by spraying, injecting, scattering on a surface of the concrete, scattering in a mould, or scattering on the surface of any concrete object.

In an embodiment of the method, the small light-emitting glass pieces are made from glass and a light-emitting pigment, where the light-emitting pigment has one of the following compositions: SrAl₂O₄ : Eu, Dy, Sr₄AIi₄O_2S : Eu²⁺, Dy³⁺, Sr₂MgSi₂O₇ : Eu²⁺, Dy³⁺, CaAl₂O₄ ! Eu^ Nd³⁺ or Y₂Al₂O₄ : Eu²⁺, Nd³⁺.

In an embodiment of the method, the light-emitting pigment comprises a sulphide composition, or it is made from an alkaline rare earth element or one or more metals chosen from calcium, strontium, barium and magnesium, or one or more oxides chosen from silicon dioxide, europium oxide, dysprosium, neodymium oxide, yttrium oxide and sulphur dioxide.

In an embodiment of the method, the light-emitting pigment can emanate visible light.

In an embodiment of the method, the amount of the light-emitting pigment used varies from 1 to 99%.

In an embodiment of the method, the amount of the light-emitting pigment used is about 10% or 40%. In an embodiment of the method, the light-emitting pigment can emanate visible light after being excited by black light or another kind of invisible light that directly activates the light-emitting pigment.

Description of the embodiments

The light-emitting pigment has one of the following chemical compositions: SrAl₂O₄ : Eu, Dy, Sr₄AIi₄O₂₅ : Eu²⁺, Dy³⁺, Sr₂MgSi₂O₇ : Eu²⁺, Dy³⁺,

CaAl₂O₄ : Eu²⁺, Nd³⁺ or Y₂Al₂O₄ : Eu²⁺, Nd³⁺, but it can also contain a sulphide composition or it can be prepared from an alkaline rare earth or another metal such as calcium, strontium, barium, aluminium, or magnesium, or from silicon dioxide, europium oxide, dysprosium, neodymium oxide, yttrium oxide, sulphur dioxide, or any other light-emitting pigment capable of emanating light in the dark after the excitation of these light-emitting or luminescent pigments by daylight, artificial light or black light.

These light-emitting pigments are also called "glow in the dark" pigments. They can be admixed to or dispersed in glass or plastic, using the light-emitting pigments in an amount of 10% by weight, or in an amount of either more or less than 10%, for example in an amount of 1-99%, or they are introduced into or applied to the small pieces of glass (also called frit or "grit") or plastic particles (also called granulates or masterbatches) in the form of a coating, varnish, paint, or an adhesive layer, or introduced or applied by heating. The light-emitting pigments are introduced into, or applied to the surface of, the concrete as an adhesive layer, a paint or coating on the glass.

This can be done for example by admixing the light-emitting pigments to boron glass or low-fusion glass, or alternatively by working them into or onto the glass.

This glass is then, or can then be, broken up for example by subjecting a plate glass to accelerated cooling or by crushing or grinding the glass into small pieces, or by making small glass pieces in another way.

The resulting pieces of glass can be regular or irregular in shape, solid or hollow, or otherwise varying in shape and size. They can measure for example 3-5 mm, but other sizes, ranging from 10 microns to 25 centimetres, are also possible.

The small glass pieces can have different melting points and different coefficients of expansion; in other words, they can have a different expansion at higher temperatures.

In an embodiment, a suitable glass with a suitable melting point of 1030⁰C is obtained by adjusting the composition of the glass with silicon dioxide (e.g. quartz sand), used in an amount of 70-80%, as the main constituent, and admixing calcium oxide, magnesium oxide and aluminium oxide to it. Glass having a melting point of for example 1400, 1200, 1000 or 900⁰C can be obtained by varying the composition to some extent.

The mixture of silicon dioxide, calcium oxide, magnesium oxide and aluminium oxide is heated to a temperature of for example 1400⁰C and centrifuged at a low speed.

Fusing these components together gives the basic composition of the light-emitting glass. After fusing the components together, the glass is rapidly cooled for example in cold water, or in a different method it is poured on a concrete floor having a very different temperature. The glass shatters here, due to the temperature difference. This gives small glass fragments measuring a few millimetres or less (glass dust). The small glass particles are then heated a second time to, for example, 1400⁰C, after which the temperature of the glass is slowly reduced preferably to 900⁰C in a tempering process, but this temperature can also be 1000, 1200 or 1340⁰C, depending on the composition of the glass. This process gives a glass paste. The photoluminescent pigments are applied to this tempered glass which is being slowly centrifuged and slowly cooled to a temperature of preferably 900⁰C. The photoluminescent pigments will have been treated with waterglass, used in an amount of preferably 1%, for example between 0.5 and 2%. Thanks to the treatment with waterglass, the light-emitting pigment can withstand a brief high-temperature cycle, since it is protected by the waterglass.

According to the invention, a balance is found between the glass-heating cycle and the properties of the photoluminescent pigments, since these pigments have a limited thermal stability of up to about 600-800⁰C, depending on the specific composition of the pigments in question.

In this case, the photoluminescent pigment is slowly brought from the middle of the machines to the outside of the glass paste. The amount can be 5 or 10%, but other figures, ranging from 15, 20 or 25 to 40 or even up to 60% are also possible. By gradually cooling the pigment-containing glass and possibly rolling it, glass fragments or glass plates are obtained, varying in thickness from 5cm to 2 mm. The plates are then broken up into smaller irregular glass pieces measuring 1-3, 3-5 or 5-7 mm. Alternatively, the pigment-containing glass paste is poured into a mould to obtain pre- shaped glass pieces, where the mould contains for example small gravel particles as a form, measuring 3 x 1.5 x 2 cm.

The small pieces of glass or the small glass pebbles can then be used in the concrete. This glass frit or "grit" or the plastic masterbatch or the plastic granulate can melt at various melting points, such as +800 or +1050⁰C for glass, or at other temperatures from +10⁰C to +2000⁰C.

The small pieces of glass can be optionally pressed, polished, either matte or bright, or further processed with glass colours or other reflecting pigments.

The small light-emitting glass or plastic pieces described above can be dispersed in concrete, scattered in or on it, or placed in or on top of a mould to form a top or bottom layer there, or they can be introduced into, or applied to the surface of, the concrete as a top layer, using an adhesive, or they can be incorporated in another way.

In one of the embodiments, the invention provides a method for introducing into the concrete or applying to the concrete a coating that contains small light-emitting glass pieces.

The small light-emitting plastic pieces (masterbatches or granulates) can be prepared from plastics such as PP, PE, PS, PA, PC, PVC, PVB, PMMA or other plastics, or types of rubber. The support for the light-emitting pigments can also be aluminium, other metals or other materials, in which case the small plastic or glass pieces or other small pieces described above are introduced into or applied to the concrete on these supports.

The resulting objects made of concrete in the form of for example paving stones, pavement kerbs, concrete slabs or other concrete objects or surfaces have a light- emitting property, because the small pieces of glass, plastic or another material glow in the dark. More specifically, the concrete becomes light-emitting in the dark, or at least the small plastic or glass particles in it do so, owing to the introduction of light-emitting plastic or glass pieces into concrete or their application to it, or owing to the addition of small light-emitting glass or plastic pieces to the surface of the concrete.

In one method used to achieve this, the small light-emitting glass pieces are scattered at the bottom of a mould or else applied by spraying, adhesion, or in another way involved in the production process, after which the concrete is sprayed or poured into the mould and then treated by the usual processing method. The treated surface with the small glass or plastic pieces or light-emitting pigments is combined with other light-emitting materials and polished or smoothed down, or treated in such a way that the small light-emitting glass pieces or the small light-emitting plastic pieces end up on the surface. These pieces can then emit light after being excited by daylight or artificial light. However, other processing methods are also possible.

The small light-emitting glass or plastic pieces incorporated in the concrete also react to black light. Depending on the type of light-emitting pigment used, the small light- emitting glass or plastic pieces can glow in light of various colours, such as white, blue, dark blue, yellowish green, light blue, purple, red, orange and other colours.

A special decorative light can be produced in the dark. It is also possible to obtain a concrete whose glass pieces emit light in the dark if small light-emitting glass pieces glowing in different colours are incorporated in it.

According to the invention, a concrete is obtained that contains small glass or plastic pieces capable of emitting light in the dark. This concrete can be used to make various products, such as paving stones, pavement kerbs, quay cladding, slabs, tubs, floors, thresholds, stairs, internal walls, decorative objects, plant boxes, parasol holders, lamp- holders and other objects and products made of concrete, such as brick-type blocks, tiles, pebbles or gravel-like products.

In an embodiment, the invention relates to a method and application for incorporating the above small glass pieces into concrete or applying them to it, so the concrete - after the treatment - contains small glass pieces that emit light in the dark.

The techniques used for this treatment ensure that glass or plastic is present on the concrete or on the surface of the concrete. For example, the concrete is smoothed down, or a coating is applied to its top layer, so the glass, plastic or other material into or onto which the light-emitting pigments have been introduced glows in the dark. The way of introduction or application can vary greatly - thus, by means of a resin, an adhesive, or a plastic that adheres to the concrete, or by means of application of a coating into which small glass or plastic pieces have been incorporated that emit light in the dark.

In an alternative method, the small glass or plastic pieces are incorporated by inserting them into a mould, or by scattering them on the bottom of a mould, so they are introduced into the concrete, or they are for example applied to the concrete as a top coat, or introduced into or applied to it in another way, after which the concrete can be for example smoothed down, washed clean, or treated further, or the top layer with the small glass pieces in it is treated in such a way that the small glass or plastic pieces break through the concrete and end up on its surface, if they are not present there already.

hi an embodiment, the method is used for applying to or gluing in or on the concrete the small glass pieces or other materials that contain light-emitting pigments or which are provided with a light-emitting pigment as described above. The method includes rendering the small glass or plastic pieces visible on the surface of the concrete and subsequently treating the concrete, for example by smoothing it or treating in some other way. In this way, a concrete with a light-emitting property is obtained because the small glass pieces or the small pieces of another material comprising light-emitting pigments can emit light in the dark, but also by directly reacting to black light or another light such as UV radiation or radiation outside the visible frequency range, according to the luminescence response of light-emitting pigments.

In another embodiment, the invention relates to a product made of concrete and containing small glass pieces that can emit light, which products include brick-like blocks, paving stones, kerb-stones, external walls, internal walls, stairs, small posts (e.g. for road directions), indicators, traffic items, safety items, warning items, plant boxes, containers, slabs, and obstacles ensuring road safety.

In an embodiment, the invention relates to a method for introducing the small luminescent glass or plastic pieces described above into concrete, or applying them to concrete, with the aid of an adhesive or a layer of paint or another coating, for example by spraying, injecting, scattering over concrete or scattering in a mould into which concrete is then poured, or scattering them on the surface of any object made of concrete.

In this way, part of the concrete provided with small light-emitting glass or plastic pieces can be made to glow in the dark. These small luminescent plastic or glass pieces are made of light-emitting pigments and glass or plastic as described above, where the amount of the light-emitting pigments used can vary from 1 to 99% and is preferably 10%, but it can also be 40% or have another value.

In an embodiment of the invention, products made of concrete are obtained that emit light in the dark and at twilight by exciting them with black light, so they glow. If black light is used for the excitation, various light-emitting pigments can be employed that would have an unsatisfactory performance without black light. This excitation can be effected near the concrete and can involve an LED black light, a TL black light or another kind of invisible light that directly activates the light-emitting pigments.

Claims

1. Method for making a product from concrete, which method comprises the introduction of small light-emitting glass pieces into the product made of concrete or their application to the surface of the product made of concrete, where the small glass pieces contain a light-emitting pigment, either by the introduction of a coating into which small luminescent glass pieces have been incorporated into the concrete or its application to the top layer of the concrete, with the aid of a resin, an adhesive, or a plastic of the type that adheres to the concrete, or by the insertion of the small light-emitting glass pieces into a mould by scattering them on the bottom of the mould and then pouring concrete over them, or by the application of the small glass pieces to the concrete in the form of a top layer, and by making the small glass pieces visible on the surface of the concrete, after which the concrete is further processed, smoothed down or otherwise treated, so that a product made of concrete is obtained that has a light-emitting surface, with small glass pieces comprising light-emitting pigments that can emit light in the dark.

2. Method according to Claim 1, wherein the small glass pieces are made visible in a way that includes the smoothing-down of the surface of the concrete.

3. Method according to Claim 1, wherein the small glass pieces are made visible in a way that includes washing of the surface of the concrete clean.

4. Method according to any one of the preceding claims, wherein the concrete product containing the small light-emitting glass pieces is chosen from bricks, paving stones, kerb-stones, external walls, internal walls, stairs, small posts, road direction markers, indicators, traffic items, safety items, warning items, plant boxes, containers, slabs, and obstacles ensuring road safety.

5. Method according to any one of the preceding claims, wherein the small light- emitting glass pieces are added to the product made of concrete, dispersed in it or introduced into it or applied to it, with the aid of an adhesive or paint layer or another coating or by means of spraying injecting, scattering them on the surface of the concrete or scattering them in a mould or on the surface of any object made of concrete.

6. Method according to Claim 1, wherein the small light-emitting glass pieces are made from glass and light-emitting pigments, where the light-emitting pigment has one of the following chemical compositions: SrAl₂C^ : Eu, Dy, Sr+AluC^s : Eu²⁺, Dy³⁺, Sr₂MgSi₂O₇ : Eu²⁺, Dy³⁺, CaAl₂O₄ : Eu²⁺, Nd³⁺ or Y₂Al₂O₄ : Eu²⁺, Nd³⁺.

7. Method according to Claim 1 or Claim 6, wherein the light-emitting pigment comprises a sulphide composition, or it is made from an alkaline earth element or one or more metals chosen from calcium, strontium, barium and magnesium, or one or more oxides chosen from amongst silicon dioxide, europium oxide, dysprosium, neodymium oxide, yttrium oxide and sulphur dioxide.

8. Method according to Claim 1, wherein the light-emitting pigment can emanate visible light.

9. Method according to any one of the preceding claims, wherein the amount of the light-emitting pigment varies from 1 to 99%.

10. Method according to any one of the preceding claims, wherein the amount of the light-emitting pigment is about 10% or 40%.

11. Method according to any one of the preceding claims, wherein the light-emitting pigments can emanate visible light after being excited by black light or another kind of invisible light that directly activates the light-emitting pigment.