3D PRINTING OF A REFLECTOR USING POLYMER FILLED WITH METAL COATED GLASS OR MICA PARTICLES AND REFLECTOR OBTAINABLE THEREBY

Abstract

The invention provides a method for 3D printing a 3D item (10), the method comprising providing a filament (320) of 3D printable material (201) and printing during a printing stage said 3D printable material (201), to provide said 3D item (10) comprising 3D printed material (202), wherein the 3D printable material (201) further comprises particles (410), wherein the particles (410) comprise one or more of glass and mica, wherein the particles (410) have a coating (412), wherein the coating comprises one or more of a metal coating and a metal oxide coating, and wherein the particles (410) have a longest dimension (A1) having an longest dimension length (L1) selected from the range of 10 m-2 mm, and wherein the particles have an aspect ratio of at least 10.

Claims

1. A method for manufacturing a reflector (10) by 3D printing, the method comprising providing a filament (320) of 3D printable material (201) and printing during a printing stage said 3D printable material (201), to provide said reflector (10) comprising 3D printed material (202), wherein the 3D printable material (201) further comprises particles (410), wherein the particles (410) comprise one or more of glass and mica, wherein the particles (410) have a coating (412), wherein the coating comprises one or more of a metal coating and a metal oxide coating, and wherein the particles (410) have a longest dimension (A1) having an longest dimension length (L1) selected from the range of 10 m-2 mm, and wherein the particles have an aspect ratio of at least 10, wherein the coating (412) comprises a light reflective material, and wherein the 3D printable material (201) comprises a polymeric material which is transparent to light.

2. The method according to claim 1, wherein the particles (410) are flake-like having an longest dimension length (L1) selected from the range of 20 m-1 mm and an aspect ratio of at least 20.

3. The method according to any one of the preceding claims, wherein the particles (410) comprise one or more of mica flakes and glass flakes.

4. The method according to any one of the preceding claims, wherein the 3D printable material (201) comprises up to 40 wt. %, relative to the total weight of the 3D printable material (201), of the particles (410).

5. The method according to any one of the preceding claims, wherein the 3D printable material (201) comprises in the range of 1-5 wt. %, relative to the total weight of the 3D printable material (201), of the particles (410).

6. The method according to any one of the preceding claims, wherein the 3D printable material (201) comprises one or more of polystyrene (PS), polycarbonate (PC), polyethylenetelepthalate (PET), polymethylmethacrylate (PMMA), and copolymers of two or more of these.

7. The method according to any one of the preceding claims, wherein the particles (410) comprise silver or aluminum coated mica or glass particles.

8. The method according to any one of the preceding claims, the method comprising printing during the printing stage said 3D printable material (201) on a substrate (1550), wherein the substrate (1550) has the shape of a reflector with one or more of a curved face (1021), a facetted face (1022), and faces (1023) configured relative to each under an angle.

9. A 3D printed reflector (10) obtainable by a method according to any one of claims 1 to 8, wherein the 3D printed reflector (10) comprises a 3D printed material (202), wherein the 3D printed material (202) comprises a thermoplastic material comprises particles (410), wherein the particles (410) comprise one or more of glass and mica, wherein the particles (410) having a coating (412), wherein the coating (410) comprises one or more of a metal coating and a metal oxide coating, and wherein the particles (410) have a longest dimension (A1) having an longest dimension length (L1) selected from the range of 10 m-2 mm, and wherein the particles have an aspect ratio of at least 10.

10. The 3D printed reflector (10) according to claim 9, wherein the particles (410) have an longest dimension length (L1) selected from the range of 20 m-1 mm and an aspect ratio of at least 20, and wherein the 3D printable material (201) comprises up to 40 wt. %, relative to the total weight of the 3D printable material (201), of the particles (410).

11. The 3D printed reflector (10) according to any one of the claims 9 and 10, wherein the 3D printable material (201) comprises in the range of 1-5 wt. % of the particles (410), relative to the total weight of the 3D printable material (201), and wherein the 3D printable material (201) comprises one or more of polystyrene (PS), polycarbonate (PC), polyethylenetelepthalate (PET), polymethylmethacrylate (PMMA), and copolymers of two or more of these.

12. The 3D printed reflector (10) according to any one of the claims 9 to 11, wherein the particles (410) comprise one or more of coated mica flakes or coated glass flakes.

13. A reflector (1) comprising a specular reflective surface (2), wherein the reflector (1) comprises the 3D printed reflector (10) according to any one of the preceding claims 9-12, and wherein at least part of the reflective surface (2) is provided by the 3D printed reflector (10).

14. A lighting system (1000) comprising (a) a light source (1010) configured to generate light source light (1011) and (b) a reflector (1) according to claim 13 configured to reflect at least part of said light source light (1011).

15. A 3D printable material (201) for use in the method according to any one of claims 1 to 8, wherein the 3D printable material (201) comprises a polymer with particles (410) embedded therein, wherein the particles (410) comprise one or more of glass and mica, wherein the particles (410) have a coating (412), wherein the coating comprises one or more of a metal coating and a metal oxide coating, and wherein the particles (410) have a longest dimension (A1) having an longest dimension length (L1) selected from the range of 10 m-2 mm, and wherein the particles have an aspect ratio of at least 10.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which:

[0059] FIGS. 1a-1b schematically depict some general aspects of the 3D printer;

[0060] FIGS. 2a-2d schematically depict some aspects of the particles, such as flakes, that can be used herein; and

[0061] FIGS. 3a-3d schematically depict some applications, including 3D printed items.

[0062] The schematic drawings are not necessarily on scale.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0063] FIG. 1a schematically depicts some aspects of the 3D printer. Reference 500 indicates a 3D printer. Reference 530 indicates the functional unit configured to 3D print, especially FDM 3D printing; this reference may also indicate the 3D printing stage unit. Here, only the printer head for providing 3D printed material, such as a FDM 3D printer head is schematically depicted. Reference 501 indicates the printer head. The 3D printer of the present invention may especially include a plurality of printer heads, though other embodiments are also possible. Reference 502 indicates a printer nozzle. The 3D printer of the present invention may especially include a plurality of printer nozzles, though other embodiments are also possible. Reference 320 indicates a filament of printable 3D printable material (such as indicated above). For the sake of clarity, not all features of the 3D printer have been depicted, only those that are of especial relevance for the present invention (see further also below).

[0064] The 3D printer 500 is configured to generate a 3D item 10 by depositing on a receiver item 550, which may in embodiments at least temporarily be cooled, a plurality of filaments 320 wherein each filament 20 comprises 3D printable material, such as having a melting point T.sub.m. The 3D printer 500 is configured to heat the filament material upstream of the printer nozzle 502. This may e.g. be done with a device comprising one or more of an extrusion and/or heating function. Such device is indicated with reference 573, and is arranged upstream from the printer nozzle 502 (i.e. in time before the filament material leaves the printer nozzle 502). The printer head 501 may (thus) include a liquefier or heater. Reference 201 indicates printable material. When deposited, this material is indicated as (3D) printed material, which is indicated with reference 202.

[0065] Reference 572 indicates a spool or roller with material, especially in the form of a wire. The 3D printer 500 transforms this in a filament or fiber 320 on the receiver item or on already deposited printed material. In general, the diameter of the filament downstream of the nozzle is reduced relative to the diameter of the filament upstream of the printer head. Hence, the printer nozzle is sometimes (also) indicated as extruder nozzle. Arranging filament by filament and filament on filament, a 3D item 10 may be formed. Reference 575 indicates the filament providing device, which here amongst others include the spool or roller and the driver wheels, indicated with reference 576.

[0066] Reference A indicates a longitudinal axis or filament axis.

[0067] Reference C schematically depicts a control system, such as especially a temperature control system configured to control the temperature of the receiver item 550. The control system C may include a heater which is able to heat the receiver item 550 to at least a temperature of 50 C., but especially up to a range of about 350 C., such as at least 200 C.

[0068] FIG. 1b schematically depicts in 3D in more detail the printing of the 3D item 10 under construction. Here, in this schematic drawing the ends of the filaments 320 in a single plane are not interconnected, though in reality this may in embodiments be the case.

[0069] Hence, FIGS. 1a-1b schematically depict some aspects of a fused deposition modeling 3D printer 500, comprising (a) a first printer head 501 comprising a printer nozzle 502, (b) a filament providing device 575 configured to provide a filament 320 comprising 3D printable material 201 to the first printer head 501, and optionally (c) a receiver item 550. In FIGS. 1a-1b, the first or second printable material or the first or second printed material are indicated with the general indications printable material 201 and printed material 202.

[0070] FIGS. 2a-2d schematically depict some aspects of the particles 410. Some particles 410 have a longest dimension A1 having a longest dimension length L1 and a minor axis A2 having a minor axis length L2. As can be seen from the drawings, the longest dimension length L1 and the minor axis length L2 have a first aspect ratio larger than 1. FIG. 2a schematically depicts a particle 410 in 3D, with the particle 410 having a length, height and width, with the particle (or flake) essentially having an elongated shape. Hence, the particle may have a further (minor or main) axis, herein indicated as further axis A3. Essentially, the particles 410 are elongated thin particles, i.e. L2<L1, especially L2<<L1, and L2<L3, especially L2<<L3. L1 may e.g. be selected from the range of 1-500 m; likewise L3 may be. L2 may e.g. be selected from the range of 0.1 m-10 m. Also L3 may e.g. be selected from the range of 0.1 m-10 m. However, L2 and/or L3 may also be longer, such as up to 5 mm, such as up to 1 mm, like up to 100 m.

[0071] FIG. 2b schematically depicts a particle that has a less regular shape such as pieces of broken glass, with a virtual smallest rectangular parallelepiped enclosing the particle.

[0072] Note that the notations L1, L2, and L3, and A1, A2 and A3 are only used to indicate the axes and their lengths, and that the numbers are only used to distinguish the axis. Further, note that the particles are not essentially oval or rectangular parallelepiped. The particles may have any shape with at least a longest dimension substantially longer than a minor axis or minor axes, and which may essentially be flat. Especially, particles are used that are relatively regularly formed, i.e. the remaining volume of the fictive smallest rectangular parallelepiped enclosing the particle is small, such as less than 50%, like less than 25%, of the total volume.

[0073] FIG. 2c schematically depicts in cross-sectional view a particle 410 including a coating 412. The coating comprises a light reflective material. For instance, the coating may comprise a (white) metal oxide. In other embodiments, the coating may essentially consist of a metal, such as an Ag coating. In other embodiments the coatings may only be on one or both of the large surfaces and not on the thin side surfaces of the particles. The light reflective material may preferably have a reflectivity of at least 80%. More preferably, light reflective material may have a reflectivity of at least 85%. Most preferably, light reflective material may have a reflectivity of at least 88% such as for example 90 or 95%. For instance, aluminium serves as a good reflector of visible light (approximately 92%).

[0074] FIG. 2d schematically depicts a relatively irregularly shaped particle. The particulate material that is used may comprise e.g. small broken glass pieces. Hence, the particulate material that is embedded in the 3D printable material or is embedded in the 3D printed material may include a broad distribution of particles sizes.

[0075] FIG. 3a schematically depicts a lighting system 1000 comprising a) a light source 1010 configured to generate light source light 1011 and b) a reflector 1, such as defined above, configured to reflect at least part of said light source light 1011.

[0076] In yet another embodiment, the reflector shaped substrate(s) can produce reflectors with 10, 25 and 40 degrees full width half maximum. In an embodiment, the reflector shaped support may thus have the shape and smoothness of a smooth reflector (see e.g. FIG. 3b). In another embodiment, the reflector shaped table might have the shape and smoothness of a faceted reflector. The facets may have areas of larger than 16 mm.sup.2, such as in the range of 16-1600 mm.sup.2. However, the facets may also be smaller, such as in the range of 1-16 mm.sup.2, or even smaller, such as in the range of 0.01-1 mm.sup.2. Such fine facets or structures provide smoother beams.

[0077] In yet another embodiment, we suggest a reflector shaped table which has a shape and smoothness of a spiral faceted reflector. The fine facets in a tight spiral are desired to achieve a smooth beam. In yet another embodiment, we suggest a reflector shaped table which has a shape and smoothness of a hybrid reflector. It comprises facets near the light source in order to obtain a beam without a black hole (see FIG. 3c). More remote from the light source, the reflector may not be facetted. In yet another embodiment, we suggest a reflector shaped table which has a shape and smoothness of an engineered structure including but not limited to including a textured, orange peel and stochastic design. Hence, essentially any reflector 1 may include one or more 3D parts comprising the herein described 3D item 10 having reflective properties. Hence, parts of the reflectors 1 in FIGS. 3b-3c are 3D printed, and include the 3D item 10.

[0078] For printing lamps and luminaires, we suggest the use of a smooth reflector shape which is placed on the print platform. The particles can be applied by e.g. spray coating onto the smoot reflector shape. Subsequently, the printer can print on top of such a surface taking over aligned particles (FIG. 3d).

[0079] Here we suggest using glass flakes with a metal or a metal oxide coating. Such glass flakes show specular reflection and act as small mirrors. Here we suggest using glass flakes with a metal, metal oxide coating. For obtaining glitter effect the flakes have an aspect ratio (size/thickness) of 20 or larger. The average size of the flakes is in the range 20 m-1 mm. The flakes can be brought into a polymer such as PC, PMMA, and PET at a concentration up to 40 wt %. The Host polymer is preferentially a transparent polymer. It is also possible to combine with dyes to maintain glittering effect without inducing scattering. In may also comprise a luminescent or absorbing dye.

[0080] Several examples were printed with PC as printable material with glass flakes embedded therein. The glass flakes had a silver coating, with a thickness of about 0.1 m. The concentration of the particles was about 4 wt. % in the examples. The particles had particles sizes of 20, 60 and 100 m, respectively, and thicknesses of about 1 m. The products thus obtained had, though a silver coating was used, a golden appearance.

[0081] The term substantially herein, such as substantially consists, will be understood by the person skilled in the art. The term substantially may also include embodiments with entirely, completely, all, etc. Hence, in embodiments the adjective substantially may also be removed. Where applicable, the term substantially may also relate to 90% or higher, such as 95% or higher, especially 99% or higher, even more especially 99.5% or higher, including 100%. The term comprise includes also embodiments wherein the term comprises means consists of. The term and/or especially relates to one or more of the items mentioned before and after and/or. For instance, a phrase item 1 and/or item 2 and similar phrases may relate to one or more of item 1 and item 2. The term comprising may in an embodiment refer to consisting of but may in another embodiment also refer to containing at least the defined species and optionally one or more other species.

[0082] Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein.

[0083] The devices herein are amongst others described during operation. As will be clear to the person skilled in the art, the invention is not limited to methods of operation or devices in operation.

[0084] It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb to comprise and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. The article a or an preceding an element does not exclude the presence of a plurality of such elements. The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the device claim enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

[0085] The invention further applies to a device comprising one or more of the characterizing features described in the description and/or shown in the attached drawings. The invention further pertains to a method or process comprising one or more of the characterizing features described in the description and/or shown in the attached drawings.

[0086] The various aspects discussed in this patent can be combined in order to provide additional advantages. Further, the person skilled in the art will understand that embodiments can be combined, and that also more than two embodiments can be combined. Furthermore, some of the features can form the basis for one or more divisional applications.

[0087] It goes without saying that one or more of the first (printable or printed) material and second (printable or printed) material may contain fillers such as glass and fibers which do not have (to have) influence on the on T.sub.g or T.sub.m of the material(s).