Patent Application
20210396911
The present invention relates generally to optics constructed of optical grade silicone. More particularly, the present invention discloses an article and mold process for forming an optical grade silicone lens by multiple shot injection molding steps and which incorporates a glow in the dark phosphoric composition. The multi-shot injection molded lens can be incorporated into any light transferring application not limited to fog lamps, headlamps, or any other lighting application which, upon turning off the lamp or illuminating source, provides for the phosphorescent material incorporated into the silicone lens to continue to glow for an extended period of time. Applications of the present invention can include without limitation automotive lighting, such as in order to create desired branding and styling variations. Additional safety applications are also envisioned.
The prior art is documented with examples of head lamp or other types of lighting devices utilizing a lens component. The prior art also discloses the use of glow in the dark phosphor materials integrated into various materials not limited to plastics and the like.
Among the prior art are references which combine aspects of these individual teachings, a first of these being had with reference to US 2019/0331321 to Tepo et al, and which teaches a light fixture includes a flexible shroud, an outer housing, and a light source within a light engine. The light engine couples within the outer housing so as to define a gap between the light engine and an inner perimeter of the outer housing. The flexible shroud forms at least first and second edge portions so that the light engine couples with the first edge portion, and the inner perimeter of the outer housing couples with the second edge portion, so that the flexible shroud covers at least part of the gap. A shroud for a light fixture may include a flexible shroud that defines one or more edges. The shroud may include one or more coupling features along the one or more edges. The flexible shroud may form a thickness variation at the coupling feature, to engage a corresponding coupling feature of a light fixture.
U.S. Pat. No. 5,717,282, to Oomen et al., teaches a display device including a display screen provided with phosphors, and coated with a spectrally selective, light-absorbing coating comprising silicon oxide and at least two dyes. The spectral transmissions for blue, green and red phosphor light are chosen to be such that the electron currents towards the blue, green and red phosphors for obtaining white D (6,500K) are substantially equal.
U.S. Pat. No. 6,375,864 to Phillips et al. discloses a molded, extruded or formed phosphorescent plastic article phosphorescent phosphor pigments that emit light in the visible spectrum, in combination with polymer-soluble daylight fluorescent dyes, in transparent or translucent resins. The plastic articles exhibit fluorescent daylight color and a glow-in-the-dark luminescence having a color similar to that of the daylight color.
U.S. Pat. No. 6,911,771 to Conrady discloses a fluorescent film for use with a low-pressure discharge lamp formed as a silicone elastomer in which luminescent particles are embedded. The film is formed by the steps of (a) mixing a hydroxyl polydiorganosiloxane with an organohydrogen siloxane. (b) adding luminescent particles, and (c) generating a chemical reaction by means of a platinum catalyst at room temperature.
Finally. US 2009/0315447 to Appel et al., teaches a light source, especially a fluorescent lamp, including at least one bulb, a silicon rubber which is resistant to high temperatures being arranged on the bulb. The silicon rubber is provided with at least one pigment influencing the color appearance and light saturation in order to generate a saturated color appearance.
The present invention discloses an article and process for forming an optical grade injection molded lens, including the steps of providing a molding assembly defining at least one interior mold configuration corresponding to desired dimensions of the lens, injection molding a liquid silicone polymer material into the mold configuration to form a base component of the lens, and incorporating a phosphorescent composition into the liquid silicone polymer. Additional steps include the incorporating of the phosphorescent composition occurring in either a single or multiple injection molding steps of the liquid silicone polymer.
Additional injection molding steps can be provided for forming a decorative feature into the lens, as well as forming a colorized ring from a further injection molding of a liquid silicone polymer. A silicone optical lens is produced according to the process of the present invention.
Reference will now be made to the attached drawings, when read in combination with the following detailed description, wherein like reference numerals refer to like parts throughout the several parts, and in which:
With reference to the attached embodiments, the present invention discloses an article and mold process for forming an optical grade silicone lens by multiple shot injection molding steps and which incorporates a glow in the dark phosphoric composition. The multi-shot injection molded lens can be incorporated into any light transferring application not limited to fog lamps, headlamps, or any other lighting application which, upon turning off the lamp or illuminating source, provides for the phosphorescent material incorporated into the silicone lens to continue to glow for an extended period of time. Applications of the present invention can include without limitation automotive lighting, such as in order to create desired branding and style differentiations. Additional safety applications are also envisioned.
As is known, light can be defined as electromagnetic radiation which has different frequencies and wavelength. The spectrum that can be picked up by the retina of a human eye is called visible light. Materials through which light can refracted, reflected, transmitted, dispersed, polarized, detected and transformed are called optical materials.
The number of optical materials has expanded recently. In the past, glass and other ceramic materials were the few materials available that offered the best refractive index values. In the instance of glass specifically, the chemical structure is formed by Silicon (Si) and Oxygen (O) with low-range arrangement. The atoms in glass are arranged randomly, and because of this structure, glass is transparent. Conversely, metals have an organized structure and therefore are not transparent.
In glass, photons (the elementary particles that form the light) are able to pass through glass without interacting with any atom. Because of this structure, it has low mechanical properties and high density (between 2.3 and 6.3 g/cm3), which can be considered a disadvantage.
Some polymers have innate properties similar to glass, but they have low physical properties. Examples of some of these polymers include the thermoplastic materials Polycarbonate (PC), and Polymethyl Methacrylate (PMMA) that are processed using injection molding, along with Epoxy resins (EPI) and thermoset materials that are compression molded. These thermoplastic and thermoset materials have advantages, including high quality surfaces reflecting the mold surface, are easily processed, and available in a variety of grades with a wide range of properties. There are disadvantages as well, including thermal stability properties which are low compared to glass.
Optically clear grades of liquid silicone rubber polymers (also LSR's) offer advantages over both glass and thermoplastic and thermoset optical polymers. The chemical structures of liquid silicone rubber and glass have elements in common. Like glass, liquid silicone rubber is also formed by Si and O, however the additional radicals in its structure are what make silicone rubbers opaque or translucent by nature. Although common in some regards, the mechanical and physical properties of liquid silicone rubber are superior to glass and carbon-based polymers. In relation to hardness, LSR's can be as flexible as 5 Shore A, or as hard as glass (approximately 90 Shore A). Its density is also a plus, it ranges between 1.1 and 2.3 g/cm3, significantly lower than glass.
Most applications specifying optical materials will be in high temperature environments. Because of LSR's good thermal stability, optically clear Liquid Silicone Rubber performs well and maintains its transparency without decreasing over time. Thermoset epoxy resins for example do not perform well, their clarity decreases and will turn black when subjected to 200° C. for 200 hours.
In contrast, LSRs offer advantages over polycarbonates as well, as the optical LSR material will maintain homogeneous light distribution over a range of wavelengths, whereas when polycarbonate is used at specific wavelengths, it will turn yellow. Most applications using optical grade silicone center on highly precise geometries that are almost impossible to fabricate with current materials and methods, and the low viscosity before cure makes molding optical grade silicone into complex shapes easier than with either glass or organic polymers.
Applying the teaches of optical grade silicone,
A first example of the multi-shot injection molded silicone lens is depicted at 10 in
Other formation processes can include utilizing urethane material in a Reaction injection molding (RIM) process to manufacture plastic molded parts. In such a process, the urethane or other thermosetting polymers are mixed in a mixing device in a fluid state and then injected as a liquid mass into a mold and allowed to expand and cure therein. Reaction injection moldings have many benefits, including low tooling costs, short lead-times, large lightweight parts, high tolerances, enhanced design finish, and desired chemical resistance properties.
Referencing again
Without limitation, common pigments used in phosphorescent materials include zinc sulfide and strontium aluminate and which can be provided in a number of colors, not limited to blue, yellow, red and green. Strontium Aluminate based luminous materials can also be doped with the rare earth mineral Europium and can re-charge limitless times by light and emit an afterglow for hours without the need of any UV lighting.
Proceeding to
A tapered and ring shaped shielding or reflector component 214 seats upon the template 212. A processor (also a PCBA) component 216, such as incorporating any number of LED or like illuminating components, is powered by one or more separate lines in the vehicle (not shown) and is integrated into a base of a lamp-style silicone lens 218 which, upon being seated upon the base housing projection 210, overlays the PCBA with LED elements.
Other components include a three dimensional retaining ring 220 with an outer annular profile which mates with an outer annular rim of the base housing 202 in a manner which biases an injection molded outer annular skit of the silicone lens 218 therebetween. An outer rigid protective lens covering 222 is provided which can be produced from any transparent material and which installs upon the outer retaining ring 220 in order to protect the interior supported silicone lens 218 and other components of the assembly.
As previously described, the pigmentation provides any desired long term after glow persistence, such as following deactivation of the LED or like illuminating components incorporated into the PCBA 216. Depending upon the phosphor composition incorporated into the second shot silicone materials, such long-persistent afterglow effect can last for an extended period of time, such as up to several hours following the deactivation of the primary LED illumination from the PCBA component 216.
As further shown in
A corresponding process for forming an optical grade injection molded lens, includes the steps of providing a molding assembly defining at least one interior mold configuration corresponding to dimensions of the lens, injection molding a liquid silicone polymer material into the mold configuration to form a base component of the lens, and incorporating a phosphorescent composition into the liquid silicone polymer.
Other process steps include incorporating the phosphorescent composition occurring in either a single or multiple injection molding steps of the liquid silicone polymer. An additional injection molding step can be provided for forming a decorative feature into the lens. The step of forming a colorized (usually outer) ring can include a further injection molding of a liquid silicone polymer.
Having described my invention, other and additional preferred embodiments will become apparent to those skilled in the art to which it pertains, and without deviating from the scope of the appended claims. This can include, without limitation, the phosphorescent entrained material being admixed into the liquid silicone (LSR) material and applied in other injection molding steps or techniques which can include reconfiguring the mold delivery channels and interior defining surfaces to incorporate the phosphorescent compounds according to varying designs.
In this manner, the multiple shot molded article and molding assembly/techniques described herein can be modified to accommodate other shapes or profiles. It is further envisioned and understood that the phosphorescent material can be provided according to any variety of colors or compositions, this including co-injecting individual phosphorescent compositions via individual injection molding channels in a given shot application or the successive injection molding of different phosphorescent compositions in succeeding molding steps.
The detailed description and drawings are further understood to be supportive of the disclosure, the scope of which being defined by the claims. While some of the best modes and other embodiments for carrying out the claimed teachings have been described in detail, various alternative designs and embodiments exist for practicing the disclosure defined in the appended claims.
The foregoing disclosure is further understood as not intended to limit the present disclosure to the precise forms or particular fields of use disclosed. As such, it is contemplated that various alternate embodiments and/or modifications to the present disclosure, whether explicitly described or implied herein, are possible in light of the disclosure. Having thus described embodiments of the present disclosure, a person of ordinary skill in the art will recognize that changes may be made in form and detail without departing from the scope of the present disclosure. Thus, the present disclosure is limited only by the claims.
In the foregoing specification, the disclosure has been described with reference to specific embodiments. However, as one skilled in the art will appreciate, various embodiments disclosed herein can be modified or otherwise implemented in various other ways without departing from the spirit and scope of the disclosure. Accordingly, this description is to be considered as illustrative and is for the purpose of teaching those skilled in the art the manner of making and using various embodiments of the disclosure. It is to be understood that the forms of disclosure herein shown and described are to be taken as representative embodiments. Equivalent elements, materials, processes or steps may be substituted for those representatively illustrated and described herein. Moreover, certain features of the disclosure may be utilized independently of the use of other features, all as would be apparent to one skilled in the art after having the benefit of this description of the disclosure. Expressions such as “including”, “comprising”, “incorporating”, “consisting of”, “have”, “is” used to describe and claim the present disclosure are intended to be construed in a non-exclusive manner, namely allowing for items, components or elements not explicitly described also to be present. Reference to the singular is also to be construed to relate to the plural.
Further, various embodiments disclosed herein are to be taken in the illustrative and explanatory sense, and should in no way be construed as limiting of the present disclosure. All joinder references (e.g., attached, affixed, coupled, connected, and the like) are only used to aid the reader's understanding of the present disclosure, and may not create limitations, particularly as to the position, orientation, or use of the systems and/or methods disclosed herein. Therefore, joinder references, if any, are to be construed broadly. Moreover, such joinder references do not necessarily infer that two elements are directly connected to each other.
Additionally, all numerical terms, such as, but not limited to, “first”, “second”, “third”, “primary”, “secondary”, “main” or any other ordinary and/or numerical terms, should also be taken only as identifiers, to assist the reader's understanding of the various elements, embodiments, variations and/or modifications of the present disclosure, and may not create any limitations, particularly as to the order, or preference, of any element, embodiment, variation and/or modification relative to, or over, another element, embodiment, variation and/or modification.
It will also be appreciated that one or more of the elements depicted in the drawings/figures can also be implemented in a more separated or integrated manner, or even removed or rendered as inoperable in certain cases, as is useful in accordance with a particular application. Additionally, any signal hatches in the drawings/figures should be considered only as exemplary, and not limiting, unless otherwise specifically specified.
The present application claims the priority of U.S. Ser. No. 63/040,799 filed Jun. 18, 2020.
| Number | Date | Country | |
|---|---|---|---|
| 63040799 | Jun 2020 | US |
