The present invention belongs to the technical field of light installations, and more particularly to a light installation comprising plastic materials with a major content of recycled plastic material. According to another aspect, the present invention related to a method for manufacturing such light installations.

Background

Light installations with continuously reduced energy consumption are of current interest. Changing the light source from light bulbs to light emitting diodes (LED) provides a significantly reduced energy consumption and along with that an improved carbon footprint of a light installation. Since further improvements of the carbon footprint by increasing the light emission efficiency of LED become smaller and smaller, other issues which take influence on the carbon footprint are under investigation. A promising initiative to improve the carbon footprint of light installation is the reduction of the carbon footprint of the involved materials. Pro-longed useful life-time of materials used in light installations as well as reuse of material components and recycling of material from used components are instrumental in order to reduce the carbon footprint of light installations.

CN 212841086 U discloses a downlight installation with a quickly detachable design, which significantly reduces the replacement of defective parts. Feasibility of reuse of substituted parts and recycling are greatly improved, thus protecting the environment by saving material. Metal screws are used for assembling different parts of the light installation. Use of recycled plastic in a downlights installation is not mentioned.

EP 0708800 B1 and US 6525158 B1 disclose stabilisation of recycled plastic materials containing styrene polymers and/or mixed polymers. The source materials for recycling occur in domestic and commercial industrial waste as well as in useful material collections. The stabilisation process comprises incorporation of heat and light stabilisers. The stabilised recycled material has good stability when exposed to heat and/or light. Use of the recycled plastic in light installations such as downlights is not mentioned.

US 5849804 discloses a process for recovering polyamide from composite articles by dissolving and precipitating the polyamide. The recycled material has good purity and stability. Use of such material in light installations such as downlights is not mentioned. US 6794419 discloses a method of recycling moulded resin consisting mainly of a thermoplastic resin to which a rubber-like material is added. Impact strength is recovered or improved. Use of such impact strength modified material in light installations such as downlights is not mentioned.

EP 0506614 B1 discloses a process for stabilising recycled mixtures of different types of thermoplastic polymers which are recovered from domestic and commercial waste, by adding at least one sterically hindered phenol and at least one phosphite or phosphonite to the recycled mixture. Use of such impact strength modified material in light installations such as downlights is not mentioned.

WO 18182437 discloses a system for marking, identification and segregation plastic waste by applying a coating comprising fluorescent markers. Sorting and recycling of plastic material is facilitated.

EP 3770482 A1 discloses a downlight installation in which the housing parts can all be made of plastic - only the electrical contact parts and a biasing spring are made of metal. No metal screws are needed during assembling or disassembling. Use of recycled plastic in the downlight installation is not mentioned.

WO 201374729 A mentions that the outer shell of the bulb in a device with light-emitting diodes (LED) can be made of recycled plastic, new plastic or other mouldable material. No teaching is given how much recycled plastic in said outer shell of the bulb may be used without significantly reducing the useful life-time of said outer shell of the bulb in reference to an outer shell of the bulb made of virgin plastic in a device with LED.

NO 321161 B1 discusses using recycled plastic in a lighting device. No teaching is given how much recycled plastic in said lighting device may be used without significantly reducing the useful life time of said lighting device in reference to a lighting device made of virgin plastic.

WO 2014040151 A discusses the use of recycled plastic in a device with LED. No teaching is given how much recycled plastic in said device with LED may be used without significantly reducing the useful life-time of said device with LED in reference to a device with LED made of virgin plastic.

US 2008264468 A discloses a solar concentrator unit, where an outer structure may be of recycled plastic. No teaching is given how much recycled plastic in said outer structure may be used without significantly reducing the useful life-time of said outer structure in reference to an outer structure made of virgin plastic. EP 0523497 A describes thermoplastic materials for high-temperature-resistant lamp housings for headlights, floodlights and signal lights, as the thermoplastic material can be recycled material. No teaching is given how much recycled plastic in said lamp housing may be used without significantly reducing the useful life-time of said lamp housing in reference to a lamp housing made of virgin plastic

There is a need for light installations with reduced carbon footprint by other means then making the light source more efficient.

Objectives

It is therefore an objective of the present invention to provide light installations which have a reduced carbon footprint.

It is a further objective to provide a method for providing light installations which have a reduced carbon footprint.

The present invention

The above mentioned objects are achieved by a light installation as defined in claim 1.

According to another aspect, the present invention concerns a method as defined by claim 13.

Preferred embodiments of the different aspects of the invention are disclosed by the dependent claims.

The present invention relates to a light installation with a reduced carbon footprint due to reuse of disassembled parts and/or material. Easiness of assembling and disassembling of the light installation is instrumental to make reuse of disassembled parts or material feasible and provide economic soundness.

A light installation according to the present invention comprises a light source and additional installation parts. These additional installation parts comprise recycled or reused plastic material, which is exposed to light and/or heat from the light source during operation of the light installation. The total of additional installation parts comprise no longitudinal metallic fastening devices, at least 60 weight % of recycled or reused plastic material in relation to the total weight of additional installation parts and at least one reversible fastening. The reversible fastening may be selected from the group consisting of quick release fastener, quarter turn joint, button push fastener, ball clamping, tongue and groove, feather and tongue, latch groove, latch lever, latch pin, snap lock, catch lock, hook-and-loop fastener, hook-and-pile fastener, touch fastener and magnetic fastener. Reversible fastenings may not comprise metal parts in order to contribute to a low carbon foot print.

Avoiding metallic parts such as longitudinal metallic fastening devices reduces the total weight of the additional installation parts. Additionally the carbon foot print of metals is usually higher than the carbon foot print of plastic materials. These two issues emphasize the weighting of recycled or reused plastic material in the light installation along with the reduction of its carbon footprint.

The total extent to which the additional installation parts comprise recycled or reused plastic material is determined by two counter acting driving forces. On the one hand a total of about 100 weight % would provide a maximum of carbon foot print reduction compared with state-of-the- art additional installation parts. On the other hand exposure of recycled or reused plastic material to light and/or heat from the light source during operation of the light installation involve degradation of the material, which limits the useful life time of the additional installation parts and thus increases their carbon foot print. Mitigation of degradation is feasible by stabilisation of the recycled or reused plastic material by addition of more or less known stabilisers or by coating of the recycled or reused plastic material.

Surprisingly it has been found that a comprisal of 60 weight % of recycled or reused plastic material in the additional installation parts provides a significant carbon foot print reduction compared with state-of-the-art additional installation parts. 60 weight % of recycled or reused plastic material can be achieved even if the heat dissipation device or heat sink in a downlight installation is made of a different material than plastic, for example from aluminium or recycled aluminium. As a matter of fact, the shape of the heat sink is more important for the cooling performance than the material it is made of. Selecting an appropriate geometry of the heat sink and selecting an appropriate recycled or reused plastic material in which the moulding of such a geometry is feasible can therefore increase the comprisal of recycled or reused plastic material in the additional installation parts to at least 75 weight % and preferably to about of 100 weight % and provide a maximum of carbon foot print reduction compared with state-of-the-art additional installation parts. Waiving longitudinal metallic fastening devices such as screws, bolts and the like contributes to a reduced carbon foot print. However the reliable connection of the different additional installation parts has to be ensured along with the easiness of assembling and disassembling the different parts. Fastenings selected from the group consisting of tongue and groove, feather and tongue, latch groove, latch lever, latch pin, snap lock and catch lock provide the desired reliability and easiness.

However these fastenings require a certain flexibility. Selection of recycled or reused plastic material within the present invention requires therefore that sufficient flexibility is ensured. Measuring indicative properties for flexibility of materials in question is therefore important. Destructive test methods such as elongation at break on small appropriate material samples in question may be used. Alternative non-destructive test methods such as carbonyl index may be used.

In a first embodiment, different selections of geometry and material of the heat sink may therefor lead to a comprisal of about 85 weight %, preferably about 90 weight %, more preferred about 95 weight % and in particular about 100 weight % of recycled or reused plastic material in the total of additional installation parts.

In another embodiment, the selected recycled or reused plastic material has an elongation at break of at least 5 %, preferably at least 10 %, more preferred at least 20 % and in particular at least 50 %.

In another embodiment, the selected recycled or reused plastic material is subjected for stabilisation in order to obtain a comprisal of 0.1-10 weight % of at least one material selected from the group consisting of heat stabiliser, light stabiliser, impact strength modifier and protective coating in the total of additional installation parts.

In another embodiment, the additional installation parts are selected from the group consisting of spring, spring cover, housing, anti-glare component, top glass, reflective cup, heat dissipation device, connector box and controlling device.

In another embodiment, the heat dissipation device comprises about 85 weight %, preferably about 90 weight %, more preferred about 95 weight % and in particular about 100 weight % of recycled or reused plastic material of its total content of plastic material. In yet another embodiment, the light installation comprises more than one, preferably more than two, more preferred more than three and in particular more than four additional installation parts comprising about 100 weight % recycled plastic material.

In another embodiment, the at least one of the additional installation parts is a reused part from a different light installation.

In another embodiment, the light source in the light installation is a light emitting diode (LED).

In yet another embodiment, the light installation is a downlights installation.

Below a more detailed explanation of the present invention is provided in the form of exemplary embodiments with reference to enclosed drawings.

Fig. 1 shows a draft of a light installation

Fig. 2 shows the elongation at break of different recycled plastic materials Fig. 3 shows a reversible fastening

Fig. 4 shows a useful recycled or reused piece of plastic irradiated by LED

Fig. 5 shows a coated recycled or reused piece of plastic irradiated by LED

Fig. 6 shows a stabilised recycled or reused piece of plastic irradiated by LED

Fig. 7 shows a cracked and no longer useful recycled or reused piece of plastic irradiated by LED

Fig. 1 shows a draft of a light installation in two parts. Fig 1A shows a side view of the light installation (1) with a central position of the light source (not shown) and with essential additional installation parts comprising lamp body (11), reflector (13), gasket (14), transparent plate (15), reversible fastening (16) and connecting ring (17). A number of 4 to 8 reversible fastenings will be arranged around periphery of connecting ring (not shown). Instead of reversible fastenings (16), the connecting ring (17) and the lamp body (11) may be provided with threads for mutual attachment. Fig IB shows a top view of the light installation (1) with a light source (not shown), lamp body (11) and cooling ribs (12) belonging to the heat dissipation device.

Fig. 2 shows elongation at break (E) in [%] versus strain (S) in [MPa] as typically obtained by tensile testing of three different recycled or reused plastic materials A, B, C. Material A has an elongation at break of less than 5% and will very likely fail when used in light installations according to the present invention. Material B could be used in light installations according to the present invention, but should be preferable be up-graded by using at least one material selected from the group consisting of heat stabiliser, light stabiliser, impact strength modifier and protective coating. Material C can be used as such, however a protective coating might be applied due to esthetical reasons.

Fig. 3 shows a reversible fastening (16a, 16b). The fastening can be easily closed or opened, which facilitates assembly and disassembly of light installations according to the present invention.

Fig. 4 shows a piece of recycled or reused plastic (21) having good resistance to degradation when exposed to light and/or heat from the light source (31).

Fig. 5 shows a piece of recycled or reused plastic (21) covered by a protective coating (22). The piece of recycled or reused plastic (21) has good resistance to degradation when exposed to light and/or heat from the light source (31).

Fig. 6 shows a piece of recycled or reused plastic (21) comprising using at least one material selected from the group consisting of heat stabiliser (23a), light stabiliser (23b), impact strength modifier (23c). The piece of recycled or reused plastic (21) has good resistance to degradation when exposed to light and/or heat from the light source (31).

Fig. 7 shows a piece of recycled or reused plastic (21) having bad resistance to degradation when exposed to light and/or heat from the light source (31). The piece of recycled or reused plastic (21) shows several cracks (24). Recycled or reused plastic (21) with such a bad resistance to degradation will very likely fail when used in light installations according to the present invention.