Photochromic glass body

Abstract

One aspect relates to a photochromic glass body, in particular a spectacle lens, comprising a base body (2) with a first side and a second side, and a layer (4) on at least one side of the base body (2), the base body (2) being composed of plastic glass with a microhardness HL, the layer (4) having a microhardness of Hc 0.5 x HL and the layer (4) being formed by polymerization of a polymerizable composition which contains at least one photochromic dye and, as a surface additive, at least one compound from the group of polyether (block) copolymers.

Description

[0001] Photochromic glass body

[0002] The present invention relates to a photochromic glass body, in particular a spectacle lens, and a use of the photochromic glass body.

[0003] Glass bodies, especially plastic lenses, preferably plastic spectacle lenses, are generally manufactured from a polymerizable mixture or composition, often also referred to as casting resin. Such a composition typically consists of plastic monomers and is in the form of a pourable or moldable mass, which, for example, to produce a plastic lens, is poured into a volume formed between two mold components arranged at a predetermined distance from each other. The resulting structure is then cured by the application of energy, i.e., the polymerizable composition or casting resin is polymerized, with the energy required for this process generally being supplied by thermal energy.

[0004] In other areas, such as the application of functional coatings, particularly functional lacquers, to plastic lenses, these coatings or lacquers are generally applied to the plastic lens as a polymerizable composition before solidification or curing occurs during a polymerization step. Such functional coatings typically exhibit lower hardness or microhardness than the underlying glass or substrate and can therefore be considered soft coatings, especially in comparison to the underlying substrate, with regard to their microhardness.Such soft coatings have the disadvantage that they do not have high strength and therefore do not offer sufficient protection against everyday external influences, and consequently degrade quickly without an additional outer protective layer, which can manifest itself in particular in a diminishing effect of their respective functionality.

[0005] US 11 / 526 031 B2 describes an approach in which such a soft layer is protected by a hard protective layer, in particular one placed over it. This provides protection for the soft layer against degrading external elements.

[0006] Confirmation copies can be obtained by influencing factors, but this approach has the disadvantages that an additional (protective) layer must be applied. This makes the manufacturing process more complex, time-consuming, and material-intensive, and also results in a hard-soft-hard structure consisting of a (comparatively) hard base body, a soft functional coating, and subsequently a hard (protective) layer. Due to differing material properties, especially differing hardnesses, such structures are generally undesirable and should be avoided.

[0007] Against this background, one aspect of the present application aims to propose an improved glass body, in particular an improved spectacle lens, which does not have the aforementioned disadvantages.

[0008] The problem is solved in particular by a glass body having the features of claim 1. The dependent claims relate to advantageous embodiments.

[0009] One aspect of the present invention relates to a glass body, in particular a spectacle lens, comprising: a base body (2) with a first and a second side, a layer (4) which is arranged on at least one side of the base body (2), wherein the base body (2) is made of plastic glass with a microhardness HL, wherein the layer (4) has a microhardness of Hc > 0.5 x HL and wherein the layer (4) is formed by polymerization of a polymerizable composition which comprises at least one photochromic dye and, as a surface additive, at least one compound from the group of polyether (block) copolymers.

[0010] The basic body is not further restricted except that it has a first side and a second side opposite the first, with the first and second sides connected by a boundary surface. The basic body can have a planar shape, in which case the first and second sides are essentially plane-parallel or parallel to each other. The basic body can also have a different shape, in particular a shape in which at least one of the two sides has a non-parallel shape, especially a curved shape. A curved shape can be described in more detail based on the radius of curvature, and a distinction is generally made between a first case, in which there is a positive radius of curvature, such a shape being called a convex shape, and a second case, in which there is a negative radius of curvature, such a shape being called a concave shape.Due to its non-parallel shape, such a base body is particularly suitable as a base body for a vitreous body, especially for a lens or spectacle lens, since the presence of at least one curved side of the base body, preferably the presence of two curved sides of the base body, gives the vitreous body an optical effect, in particular a minification or magnification effect, which makes such a vitreous body preferably suitable for use as a lens or spectacle lens.

[0011] The base body can be an unprocessed base body with respect to its first and / or second side, also referred to as a substrate or blank. In particular, if one of the two sides has already been processed with respect to its current shape, it is also referred to as a semi-finished part or product, since a glass body comprising such a base body generally undergoes at least one further processing step, preferably two or more processing steps, before its use as a lens or spectacle lens, in particular a surface processing step in which the still unprocessed side undergoes (surface) processing.

[0012] To be suitable for its later use as a lens, the base body should possess sufficient optical quality with regard to its optical imaging properties. Those skilled in the art understand optical imaging properties to encompass a multitude of determinable, characteristic quantities that can characterize a given object, such as a base body, with respect to its optical imaging properties. These include properties such as spectral transmission, color rendering, and the Abbe number. This is particularly relevant in the use of plastics as materials for the manufacture of lenses, especially ophthalmic lenses.For spectacle lenses, materials such as acrylate, poly(thio)urethane, polyacrylate, polymethyl methacrylate, polycarbonate, polydiethylene glycol bisallyl carbonate, or combinations thereof have proven preferred in recent years, although other transparent plastic materials can also be used in principle. Accordingly, the base body in one embodiment is made of plastic, and can in particular be a plastic base body, preferably a plastic lens base.

[0013] Depending on the plastic used, the base body can be formed, as described in the introduction, by polymerizing a polymerizable composition, for example by curing under controlled temperature conditions or by irradiation with electromagnetic waves, especially UV light. Alternatively, the base body can be formed by thermoplastic deformation, such as (injection) molding.

[0014] In order to be particularly suitable as a base body for a glass body or for a spectacle lens, the base body is preferably made of a transparent plastic glass, in particular of a plastic glass that is transparent in the visible spectral range or of a plastic glass that is (at least partially) transparent to visible light.

[0015] The microhardness of an object, particularly of the substrate and / or the layer, is generally determined by applying a known and well-defined test specimen to the object with a defined force, or, converted to the area of ​​the test specimen, with a defined pressure. The deformation observed upon penetration of the test specimen provides information about the hardness. Especially at penetration depths greater than or equal to approximately one-tenth of the layer thickness of the layer being tested, it is important to note, according to Bückle's rule, that this measures the composite hardness of the system and not the individual hardness of the layer.Such hardness measurements can be performed using commercially available hardness testers, such as the FISCHERSCOPE HM2000 from Helmut Fischer GmbH, Sindelfingen, for coatings thicker than 1-2 pm, or the PICODENTOR HM500 from the same company for coatings 1 pm thick or less. The measurement and calculation of material properties, such as microhardness (or Martens hardness), elastic indentation modulus, indentation creep, and the ratio of elastic to plastic deformation, are carried out according to DIN EN ISO 14577-1. Measurements can be performed with a maximum force of 300 mN, which is reached after a measurement time of 20 seconds at a temperature of 30°C. The microhardness can then be determined from the measurement once the maximum force is reached.

[0016] The base body preferably has a microhardness HL of greater than or equal to 85 N / mm². 2or 90 N / mm 2 on, preferably greater than or equal to 95 N / mm 2 , preferably greater than or equal to 100 N / mm 2 , particularly preferably of greater than or equal to 150 N / mm 2 , especially of greater than or equal to 175 N / mm 2 A base body exhibiting the aforementioned microhardness is suitable as a base body for a glass body, as it possesses a certain strength, toughness, and wear resistance, and thus good everyday usability.

[0017] The glass body comprises (at least) one layer arranged on at least one side of the base body. In a further development, the layer can also be arranged on both sides of the base body. The layer is preferably arranged directly on the base body or on one or both sides of the base body, which means that no further layer or layer is arranged between the layer and the base body. In a variation of this, the layer can also be arranged indirectly, which means that at least one, preferably two or more, additional layers or layers of a material different from the layer and the base body are arranged between the layer and the base body. Preferably, these additional layers or layers can be...These are layers that impart an additional property to the glass body, particularly the base body and / or the coating. For example, one, two, or more additional layers arranged between the base body and the coating can improve the adhesion between them or provide an additional property. This layer is not initially restricted in any way; in particular, it can be made of a material that is transparent in the visible spectral range, just like the base body, or of a material that is (at least partially) transparent to visible light. This makes the layer particularly suitable as a coating for a glass body, especially for a spectacle lens.

[0018] The layer preferably has a microhardness Hc of less than or equal to 1000 N / mm². 2 preferably less than or equal to 500 N / mm 2, especially preferably less than or equal to 250 N / mm 2 The layer therefore differs from known layers, in particular from known scratch-resistant layers or coatings, or hard lacquer layers or coatings, which are applied to or provided with a substrate to protect it, especially from mechanical damage such as scratching. Such high values ​​for the microhardness of the layer are not desirable, since a not-too-hard or rigid environment is required for the (optional) functionalization of the layer, for example, by dyes contained in the layer, especially photochromic dyes.

[0019] The layer can, in particular, be a functional layer and impart properties, preferably (additional) functional properties, to the base body it contains. In this way, a glass body has additional properties that the base body does not possess; that is, by means of the layer, a base body can be provided with additional properties or refined to obtain a (coated) glass body that exhibits the desired additional properties. Preferably, the layer can be colored. Alternatively or additionally, the layer can be more easily colored than the base body due to its material properties, since, for example, dyes penetrate the material of the layer more easily or quickly and / or adhere to the layer surface. The coloring can be carried out in an immersion bath.

[0020] The layer has a microhardness Hc that is greater than or equal to half the microhardness HL of the base body, i.e., Hc 0.5 x HL, preferably Hc 0.6 x HL, and particularly preferably Hc 0.70 x HL. Because the layer has a microhardness that is at least half the microhardness of the base body, it is characterized by increased hardness compared to conventional layers and, consequently, increased strength, toughness, and wear resistance. Advantageously, this allows a glass body to be obtained that comprises a base body and a layer arranged directly or indirectly thereto, which imparts at least one additional property to the glass body and is simultaneously not too soft. A soft layer within the meaning of the invention, in particular a layer that is too soft, has a microhardness of Hc < 0.4 x HL.In particular, because the layer has a hardness greater than or equal to 50% of the hardness of the base material, a functional layer or coating can be achieved without an additional protective layer, especially one that would protect the functional coating itself. Advantageously, this allows for the creation of a (functionally coated) glass body that requires no additional protective layer and is therefore both cost-effective to manufacture and, especially in the absence of an additional hard protective layer, lacks a hardness profile, consisting of a hard base material, a soft layer, and a subsequent hard protective layer.

[0021] The glass body is further characterized in that the layer is formed by polymerization of a polymerizable composition, wherein the polymerizable composition comprises at least one surface additive, a compound from the group of polyether (block) copolymers. Copolymers are polymers composed of two or more different monomer units. Block copolymers are built from blocks of each monomer. The properties of the copolymers can be influenced by the choice of blocks or block lengths. By adding at least one compound from the group of polyether (block) copolymers to the polymerizable composition, in addition to other components, in particular a photochromic dye, (photochromic) compounds can be formed.Dyes are embedded, which are then protected from degradation over time and can exhibit their photochromic properties in a stable manner. In particular, in combination with photochromic dyes in the polymerizable composition, the polyether (block) copolymer ensures improved performance and properties of the photochromic dyes. Preferably, the layer is formed by polymerization of a polymerizable composition. Advantageously, the layer can be formed or produced particularly cost-effectively by preparing or providing a polymerizable composition, because the polymerizable composition can first be easily applied to the substrate and then polymerized on the substrate, thus forming a strong bond with it.A person skilled in the art is familiar with a number of common methods for applying a polymerizable composition, including in particular spray coating, spin coating, dip coating, and casting. This is especially advantageous for forming the layer on a substrate that has at least one curved side. A person skilled in the art is also familiar with common methods for forming the layer by polymerizing the polymerizable composition, including in particular thermal polymerization, triggered by the application of heat to the composition, UV-induced polymerization, triggered by the presence of UV radiation to the polymerizable composition, or a combination thereof.

[0022] A preferred polymerizable composition comprises, as its main components, at least isocyanates or protected isocyanates and isocyanate-reactive components. This advantageously allows the formation of a polymerized poly(thio)urethane layer that combines very good optical properties with high everyday usability. Polymerizable compositions comprising, as their main components, two- and / or three-functional (meth)acrylates are also preferred, as they are particularly suitable for forming a polymethyl(meth)acrylate layer. Such layers are also known for their good optical properties coupled with high everyday usability. In addition to the aforementioned preferred main components, such polymerizable compositions may also contain further components, in particular various additives, which fulfill additional functions.The chemical and / or mechanical properties of such a polymerizable composition can be specifically modified. It can also be advantageous to add additives such as light and / or radical stabilizers to improve the resistance of such a layer, particularly to environmental influences and climatic conditions.

[0023] Preferably, the layer has a thickness of greater than or equal to 10 pm, more preferably greater than or equal to 30 pm, particularly preferably greater than or equal to 50 pm, but especially less than or equal to 350 pm or less than or equal to 750 pm. Advantageously, this allows the formation of a comparatively thin layer, in particular a very thin layer compared to the substrate. In this way, the amount of material required can advantageously be reduced.

[0024] Preferably, the base body has a microhardness HL of greater than or equal to 85 N / mm². 2and the layer has a microhardness Hc greater than or equal to 43 N / mm² 2 preferably greater than or equal to 50 N / mm 2 Furthermore, the base body preferably has a microhardness HL of greater than or equal to 100 N / mm². 2 and the layer has a microhardness Hc greater than or equal to 60 N / mm² 2 The base body preferably has a microhardness HL of greater than or equal to 160 N / mm². 2 and the layer has a microhardness Hc of greater than or equal to 120 N / mm² 2 Combinations of base material and layer that meet the aforementioned values ​​are characterized by particularly high suitability for everyday use as glass bodies or spectacle lenses and can be manufactured in particular with well-known plastic lens materials familiar to the expert.

[0025] Preferably, the layer is formed by gating, i.e., the layer is produced in particular by a gating process, wherein the base body is first arranged at a distance from a mold shell, forming a cavity, the cavity is appropriately sealed, and then the cavity is filled with the polymerizable composition to form the layer. Advantageously, base bodies can be reproducibly provided with a particularly thin layer in this way, especially a layer having a thickness of less than 750 pm. Preferably, the polymerizable composition for forming the layer comprises at least one crosslinking agent. Advantageously, this can promote the formation of crosslinks during polymerization, resulting in a higher microhardness in the formed layer.Preferably, by adding compounds from the group of multifunctional thiols or multifunctional alcohols, microhardness values ​​for the formed layer of Hc > 0.9 x HL, more preferably Hc > 1.0 x HL, and particularly preferably Hc > 1.1 x HL, can be achieved. Furthermore, inorganic or organic nanoparticles surface-modified with thiols or alcohols can be used. Multifunctional isocyanates or isocyanate-modified inorganic or organic nanoparticles can also be employed. In other words, this allows the formation of a layer that exhibits excellent strength and, in particular, a microhardness that is approximately equal to the hardness of the substrate and, in further developments, even exceeds it.

[0026] Preferably, the base body of the lens body is made of a plastic glass or preferably comprises (meth)acrylate, poly(thio)urethane, polyacrylate, polymethyl methacrylate, polycarbonate, polydiethylene glycol bisallyl carbonate, or combinations thereof. In this way, plastic materials familiar to those skilled in the art, and in particular commercially available ones, can be used for transparent lens bodies. The aforementioned materials, in particular, are characterized by very good optical properties combined with high suitability for everyday use as base materials for lens bodies.

[0027] Preferably, the base body is produced or formed by polymerization of a polymerizable composition, wherein the polymerizable composition of the base body comprises essentially the same substances or compounds as the polymerizable composition used to form the layer. Advantageously, by selecting a composition that is as similar as possible, preferably very similar, and particularly preferably essentially identical, to the respective polymerizable compositions of the base body and the layer, a particularly strong and durable bond between the base body and the layer can be achieved. Furthermore, this also allows for the attainment of very comparable optical properties, due to the essentially identical substances or compounds, resulting in a glass body characterized by low interference phenomena. Advantageously, the sprue layer can be substantially or even identical to the sprue.It should be colored exactly like the base body, so that no disturbing optical effects arise due to different colors.

[0028] Preferably, the difference An between the refractive index n L of the base body and the refractive index n c the layer at least at one wavelength, in particular determined at a wavelength of about 550 nm, An = |n L - n c \ < 0.2. The difference An = |n is preferred. L - n c | < 0.1. The difference An - \n is also preferred. L - n c | < 0.01, especially preferred An - |n L - n c | < 0.001, especially An = \n L - n c< 0.0001 and thus approximately identical. Advantageously, interference phenomena that arise at interfaces with different refractive indices can be prevented if the refractive index of the base body and the layer differs only slightly at at least one wavelength, preferably at two or more wavelengths, and particularly preferably at the majority of all wavelengths in the visible spectral range. The base body can have a refractive index of approximately 1.5, 1.6, 1.67, 1.72, or 1.74, where the term "approximately" can denote a deviation of less than 5%, preferably less than 1%.

[0029] Preferably, the layer is photochromic and the polymerizable composition of the layer comprises at least one photochromic dye. Advantageously, a photochromic glass body can be obtained by forming a photochromic layer on the base material; that is, the glass body acquires an additional property by providing the base material with a photochromic layer, in particular photochromic behavior, which is understood to mean, in particular, that the at least one photochromic dye contained in the composition reacts to UV light. Depending on the intensity of the incident UV light, the at least one photochromic dye causes a darkening or lightening through a reversible change in its molecular structure, also known as isomerization. A photochromic dye thus changes its absorption behavior in response to irradiation with UV light.When UV light exposure diminishes, the photochromic dye reverts to its original molecular structure and thus also to its original absorption behavior. A photochromic dye therefore enables reversible switching between dark and light tints. Naphthopyrans, spirooxazines, and / or spiropyrans are particularly suitable as photochromic dyes, exhibiting both rapid darkening and high longevity. In particular, the polymerizable composition can contain not only one photochromic dye from the aforementioned compound groups, but also two or more, and the selected photochromic dyes can also differ. Using such a composition supplemented with photochromic dyes, a photochromic layer can be formed on a substrate.a photochromic glass body is obtained, which can preferably be used as a self-tinting spectacle lens and offers a high level of wearing comfort, as the self-tinting effect makes switching between conventional corrective glasses, for example reading glasses, and sunglasses obsolete.

[0030] Preferably, the layer is colored, in particular permanently colored, and the polymerizable composition of the layer comprises at least one permanent dye. "Permanent," in particular in contrast to "photochromic," means that the dye exhibits constant absorption behavior and cannot reversibly switch between an excited (absorbing) and a non-excited (non-absorbing) state due to UV radiation. A permanent coloration therefore means a lasting, largely unchanging coloration. The dye can, for example, impart a characteristic coloration or special absorption properties, such as a filtering effect, to the composition. Such a modified composition then exhibits a new or additional property: a pre-coloration or a different transmission characteristic compared to a composition without dye.This process yields, in particular, a colored composition, advantageously forming a colored layer on the substrate or producing a colored glass body. Preferably, these are azo dyes, cyanine dyes, anthraquinone dyes, or the like, such as those commonly used in the conventional coloring of glass bodies, especially plastic spectacle lenses. In particular, the polymerizable composition can comprise not only one dye from the aforementioned compound groups, but also two or more, and the selected dyes can also differ. A person skilled in the art routinely selects a suitable dye or a mixture of suitable dyes.

[0031] In a further development of this, the layer is preferably photochromic and, in particular, permanently colored. By combining these two forms, a permanently pre-colored layer can be obtained, which exhibits a first absorption characteristic or a first transmission behavior and, upon irradiation with UV radiation, a second absorption characteristic or a second transmission behavior that differs from the first. Advantageously, by coating a base body with such a layer, a permanently colored and photochromic material can be obtained, which thereby exhibits special properties such as an initial darkening and, upon irradiation with UV radiation, a second, in a further development, even deeper darkening.Such a glass body is therefore particularly suitable for use as a sunglass lens, which exhibits an initial darkening and, upon exposure to UV radiation, especially present in the sunlight spectrum, a second, even deeper darkening.

[0032] Preferably, the glass body has at least one further layer or coating on at least the side, or in a further development, on both sides, on which the layer is applied. This coating is selected from: an anti-reflective coating; and / or a mirrored coating; and / or an easy-to-clean coating; and / or an anti-static coating; and / or an anti-fog coating; and / or a UV protection coating; and / or an IR protection coating; and / or a blue light protection coating. A person skilled in the art knows how to skillfully combine the aforementioned coatings to obtain glass bodies with different properties.

[0033] Preferably, the at least one further layer is an anti-reflective coating. Such a coating, comprising at least one single layer, generally preferably comprising alternating single layers with different refractive indices arranged one after the other, forming an interferometric multi-layer system, is based on the concept of interference, in particular destructive interference, in order to inhibit or suppress, or largely or completely suppress, the reflection of the incident light by means of destructive interference, at least for one wavelength, preferably for two or more, and particularly preferably for a plurality of wavelengths.Advantageously, this results in an anti-reflective glass body, which is therefore particularly suitable as a lens and / or spectacle lens, since it is (largely) free from disturbing reflections due to the anti-reflective coating and is characterized by high transmission.

[0034] Preferably, and in particular also as an alternative or additional to an anti-reflective coating, the at least one further layer is a reflective coating. Such a coating, comprising at least one single layer, generally preferably comprising alternating single layers with different refractive indices arranged one after the other, forming an interferometric multi-layer system, is based on the concept of interference, in particular constructive interference, to reflect the incident light by means of constructive interference for at least one wavelength, preferably for two or more, and particularly preferably for a plurality of wavelengths.Advantageously, this results in a mirrored glass body, which is therefore particularly suitable as a reflective lens and / or mirrored spectacle lens, especially for sunglasses, since it reflects incident light due to the mirror coating. Preferably, and especially as an alternative or additional to an anti-reflective and / or mirrored coating, the at least one further layer is an easy-to-clean coating characterized by low surface energy and, in particular, hydrophobic and / or oleophobic properties, which result in a glass body coated with this coating having a lower tendency to adhere to dirt, grease, and / or water. Often, such a coating also offers improved cleanability as an additional property.Advantageously, this results in a glass body that is highly suitable for everyday use, highly resistant to everyday grease- and / or water-based soiling, and easy to clean. Such an easy-to-clean coating can also be applied as the final, outermost layer as part of a multilayer (interferometric) coating system.

[0035] Preferably, and in particular also as an alternative or additional to an anti-reflective and / or mirrored coating and / or easy-to-clean coating, the at least one further layer is an antistatic coating which counteracts, in particular, a static charge on the glass body in order to prevent the adhesion of dust particles. Preferred materials for such antistatic coatings are generally metallic or at least conductive layers; materials such as ITO (indium tin oxide) and / or metal oxides are particularly preferred, especially substoichiometric metal oxides, which thereby exhibit conductivity. Such an antistatic coating can also be arranged as part of, or be present in, a multilayer (interferometric) coating system.

[0036] Preferably, and in particular also as an alternative or additional to an anti-reflective and / or mirrored coating and / or easy-to-clean coating and / or antistatic coating, the at least one further layer is an anti-fog coating, which is characterized by its ability to counteract fogging. This means, in particular, that it counteracts the formation of (water) droplets when water vapor in the air condenses (especially during temperature changes from a cold to a warm environment), thus ensuring that no individual droplets form, but rather a largely uniform film that allows for acceptable visibility and transmission. Advantageously, this results in a lens, especially a spectacle lens, that offers a high level of wearing comfort.Such an anti-fog coating can also be arranged as the final, outermost layer as part of a multi-layer (interferometric) coating system.

[0037] Preferably, and in particular also as an alternative or additional to an anti-reflective and / or mirrored coating and / or easy-to-clean coating and / or anti-static coating and / or anti-fog coating, the at least one further layer is a UV protection coating characterized by reduced transmission of UV radiation, preferably by inhibited to completely absorbing or reflective transmission of UV radiation. Advantageously, this results in a glass body that has a blocking effect with regard to the transmission of (harmful) UV radiation and is therefore particularly suitable as a lens or spectacle lens. In a lens, such UV protection can be advantageous to protect sensitive components, e.g., optical sensors, from irradiation or exposure to UV radiation.For spectacle lenses, protection against harmful UV radiation is advantageous to protect the wearer's eyes. Such a UV-protective coating can also be incorporated as part of a multi-layer (interferometric) coating system, or a corresponding coating system, optionally an anti-reflective and / or mirrored coating, can be designed to suppress light in the visible spectral range (anti-reflective coating) or deliberately reflect it (mirrored coating), while simultaneously exhibiting increased absorption or reflection of UV radiation.

[0038] Preferably, and in particular also as an alternative or additional to an anti-reflective and / or mirrored coating and / or easy-to-clean coating and / or anti-static coating and / or anti-fog coating and / or UV protection coating, the at least one further layer is an IR protection coating, which is characterized by reduced transmission behavior with respect to IR radiation, preferably by inhibited to completely absorbing transmission behavior or reflective behavior with respect to IR radiation. Advantageously, this results in a glass body that has a blocking effect with respect to the transmission of (harmful) IR radiation and is therefore particularly suitable as a lens or spectacle lens. In a lens, such IR protection can be advantageous to protect sensitive components, e.g.Optical sensors need protection from IR radiation, particularly to reduce, inhibit, or prevent the associated heat energy input. For spectacle lenses, protection from harmful IR radiation is advantageous to protect the wearer's eyes. Such an IR protective coating can also be incorporated as part of a multilayer (interferometric) coating system, or a suitable coating system, optionally an anti-reflective and / or mirrored coating, can be designed to suppress (anti-reflective) or deliberately reflect (mirrored) light in the visible spectral range while simultaneously exhibiting increased absorption or reflection of IR radiation.Further developing this, an IR protective coating can also be designed in combination with a UV protective coating, particularly as a multilayer (interferometric) coating system, thereby providing advantageous protection against radiation from both radiation ranges adjacent to the visible spectrum. This can preferably be achieved through the suitable design of a multilayer (interferometric) coating system.

[0039] Preferably, and in particular also as an alternative or additional to an anti-reflective and / or mirrored coating and / or easy-to-clean coating and / or anti-static coating and / or anti-fog coating and / or UV protection coating and / or IR protection coating, the at least one further layer is a blue-light protection coating, which is understood to be a coating that exhibits increased absorption and / or reflection of radiation from the blue spectral range. Advantageously, this results in a glass body as a lens or spectacle lens that is characterized by protection against radiation from the blue spectral range, which is particularly suspected of disrupting the human circadian rhythm. Such a blue-light protection coating can also be arranged as part of a multilayer (interferometric) coating system.A suitable layer system, optionally an anti-reflective and / or mirrored coating, can be designed to suppress light in the visible spectral range (anti-reflective coating) or to deliberately reflect it (mirrored coating), while simultaneously exhibiting increased absorption or reflection of IR radiation. In a further development of this, a blue-light protection coating can also be designed in combination with a UV-protective and / or IR-protective coating, particularly as a multilayer (interferometric) layer system, thereby providing advantageous protection against radiation from the aforementioned spectral ranges.

[0040] It goes without saying that the person skilled in the art can select any combinations, in particular synergistic combinations, from the aforementioned coatings in order to obtain a glass body which has a base body and the coating, as well as any number of further layers to obtain further advantageous properties.

[0041] Preferably, at least one of the following coatings is arranged between the layer and at least one further layer or coating, in particular selected from the above list: a buffer coating; and / or a hard coating.

[0042] By applying a buffer coating between the lens layer and at least one other layer, the impact resistance of the coated glass body can be improved or increased. It is known that such buffer coatings are generally formed as incompletely polymerized layers, thereby improving the impact resistance of the glass body. Such buffer coatings are particularly advantageous when base bodies made of relatively hard plastic glass materials, such as polyurethane and / or polymethyl methacrylate, are used as glass bodies or spectacle lenses and must meet specific impact resistance requirements, such as those stipulated by the US Food and Drug Administration (FDA) for the drop ball test.By applying a hard lacquer coating between the layer and at least one further layer, the mechanical strength, and in particular the scratch resistance, of the glass body can be improved. Especially compared to mineral glass, plastic glass base bodies exhibit lower scratch resistance and are prone to increased scratching in everyday use, particularly as glass bodies or spectacle lenses. To obtain a more resistant glass body, such a hard lacquer coating is applied as an additional layer. This coating preferably consists of siloxanes, which thus exhibits increased scratch resistance. In a further development of this, a particularly resistant glass body can be obtained by combining a buffer lacquer and a hard lacquer coating. This glass body exhibits both increased impact resistance and increased scratch resistance, making it particularly suitable as a lens.It's a spectacle lens.

[0043] One aspect concerns the use of a glass body according to the invention in lenses and glasses for spectacles of all kinds, such as corrective glasses, driving glasses, ski goggles, sunglasses, motorcycle goggles, for visors of protective helmets and the like, or for sun protection purposes in vehicles or in the construction sector, in the form of windows, protective screens, covers, roofs and the like.

[0044] The invention is described in more detail below with reference to the figures. It is understood that the present invention is not limited to the embodiments shown in the figures, and that individual features of different embodiments can be combined to form further embodiments within the scope of the accompanying claims. Identical reference numerals indicate identical or recurring elements. The figures show:

[0045] - Fig. 1 shows a first embodiment of the glass body; and

[0046] - Fig. 2 showing a second embodiment of the glass body with optional features; and

[0047] - Fig. 3 shows a third embodiment of the glass body.

[0048] Fig. 4 a schematic diagram microhardness measurements Figure 1 shows a first embodiment of a glass body 1 comprising a base body 2 and a layer 4 arranged on at least one side of the base body 2. In this embodiment, the layer 4 is arranged directly on the base body 2.

[0049] Base body 2 is formed from polythiourethane, the preferred plastic lens material. The base body is formed from a polymerizable composition, also known as a casting resin mixture, wherein the polymerizable composition comprises isocyanates and isocyanate-reactive components as its main constituents. Isocyanate-reactive components are understood to be, in particular, thiols or alcohols with two or more functional groups, i.e., SH or OH groups. Plastic lenses made from polythiourethane exhibit high suitability for everyday use, combined with very good optical imaging properties and an increased refractive index of approximately 1.60, determined at a wavelength of approximately 550 nm.They are therefore particularly suitable as lens bodies for spectacle lenses, which can very effectively correct even (somewhat) higher refractive errors, expressed in spherical equivalents of more than + / - 3.0 diopters, with an acceptable lens (center) thickness, offering particular aesthetic advantages. The lens body 2 can be produced as a polythiourethane casting using a correspondingly curved mold, so that the resulting lens body 2 already has a curved shape on one side, expressed in a base curve (BC) of BC = 3.0. The lens body 2 can have a microhardness of approximately 180 N / mm². 2 exhibit.

[0050] The resulting base body 2 and a further mold shell can then be spaced apart from each other, so that a cavity forms between the curved first side of the base body 2 and the spaced-apart mold shell, which can be sealed by means of a suitable tape or adhesive tape. The cavity can then be filled with a casting resin using a filling device, wherein the casting resin is a preferred embodiment of a polymerizable composition which may comprise isocyanates and isocyanate-reactive components as further preferred main components. In addition to these main components, the composition may also include photochromic dyes, in particular naphthopyran dyes as preferred photochromic dyes.In this way, using the above-described method, which is also called the casting method, a layer 4, in particular a photochromic layer, can be formed directly on the base body, which can have a layer thickness of about 30 pm to about 400 pm, in particular about 300-350 pm.

[0051] The (photochromic) layer 4, which forms directly on the substrate, can have a microhardness of approximately 130 N / mm². 2 The base body 2 is provided with a photochromic layer 4, resulting in a glass body 1 that exhibits photochromic properties. The glass body 1 thus obtained therefore comprises a base body 2 which, in this embodiment, acquires an additional property through the functional layer 4 formed directly onto it. The layer 4 has a microhardness (Martens hardness) of approximately 130 N / mm². 2The resulting glass body 1 exhibits a microhardness approximately 70% of that of the base body 2, thus possessing a microhardness significantly greater than half that of the base body 2 and consequently displaying above-average strength. The glass body 1 obtained in this way can be further processed as a semi-finished product in subsequent production steps, for example, by one- or two-sided surface treatment to achieve a desired optical effect, optionally by a hard lacquer coating for even higher scratch resistance, or optionally by an anti-reflective coating for higher transmission. In this way, it can be further processed into a coated lens or a coated spectacle lens. Preferably, only one-sided (machining) surface treatment is performed on the side of the base body 2 facing away from layer 4.

[0052] It goes without saying that layer 4 can also be formed on the substrate 2 using any other method. Likewise, layer 4 can be made of a different material; for example, instead of polythiourethane, it can also be made of a polymerizable composition comprising, for example, functional (meth)acrylates, in particular non-cyclic two- and / or three-functional methacrylates or acrylates, which are preferably suitable for forming a (thermoset) layer 4 of polymethyl methacrylate or polyacrylate having a refractive index of about 1.54, determined at a wavelength of about 550 nm.It is also understood that the photochromic dyes added to the polymerizable composition in the embodiment described above for the formation of layer 4 represent only an exemplary form of the achievable functionalization and that the person skilled in the art can add any further substances to such a composition in order to obtain a layer 4 with corresponding functions, whereby a glass body 1 having a base body 2 provided with such a layer 4 acquires the corresponding functions.

[0053] Figure 2 shows a second embodiment of a glass body 1, wherein a glass body 1 can serve as a semi-finished product, as described in Figure 1.

[0054] The resulting glass body 1 can be used as a semi-finished product and further coated with additional layers in subsequent production steps.

[0055] The glass body T was initially coated with a hard lacquer as a preferred buffer and / or hard lacquer coating 6 by means of an immersion coating process. In this way, the scratch resistance of the glass body 1' was increased, and it now has greater suitability for everyday use, as it is better protected against (minor) scratches.

[0056] Subsequently, a multilayer anti-reflective coating was applied to the glass body T as a preferred, further coating 8. This anti-reflective coating was formed in a dedicated high-vacuum coating system by vapor deposition, in which, in such a system, alternating low-refractive-index and high-refractive-index coating material is vaporized by means of an electron beam, and the vapor deposits as alternating, thin layers on the glass body 1', in particular on the surface of the hard lacquer coating 6. In this way, an anti-reflective, hard lacquer-coated glass body 1' was obtained, which, due to the hard lacquer coating, exhibits increased scratch resistance, and, due to the anti-reflective coating, offers high suitability for everyday use, resulting from high transmittance and the absence of disturbing reflections or residual reflections.

[0057] Figure 3 shows a third embodiment of a glass body 1, which differs in particular from the glass body 1 of Figure 1, since the glass body 1" has a layer 4 on the first and second sides of its base body 2, i.e., on both sides. This allows for improved or enhanced functionalization of the glass body 1". In particular, as a further development, a first and a second functionalization can be achieved by having different layers 4 on the first and second sides of the base body 2. In the case of identical layers 4 on the first and second sides of the base body 2, this layer 4 can preferably be formed by dip coating, wherein the base body 2 is immersed in a bath containing the polymerizable composition for forming the layer 4, in particular multiple times.The substrate is repeatedly immersed, and upon re-emergence, a thin film of the polymerizable composition adheres to both sides of the substrate 2. This process is repeated several times until the desired layer thickness of layer 4 is reached, followed by polymerization, optionally by heat (thermal) or UV radiation (UV-induced), resulting in the solidification of layer 4. Dip coating is a particularly advantageous manufacturing method, especially for layer 4 that is to be formed on both sides of the substrate 2.

[0058] Figure 4 shows a schematic diagram of microhardness measurements (plotted on the abscissa) at a corresponding penetration depth (plotted on the ordinate) for microhardness measurements on glass objects. The glass objects to be measured were arranged in a FISCHERSCOPE HM2000 microhardness tester from Helmut Fischer GmbH. For the microhardness measurement, a test specimen with a defined geometry was pressed into the glass object with a force of approximately 300 mN (millinewtons). The measuring device determines the resulting microhardness from the deformation of the glass object caused by the pressure of the test specimen, as a function of the penetration depth of the test specimen.

[0059] The solid line 101 shows the microhardness penetration depth curve of a glass body 1 from Figure 1, which has a polythiourethane base body 2 and a photochromic layer 4 formed on it, also having polythiourethane.

[0060] A comparative example is shown as dotted line 102. This is also a polythiourethane substrate, but it has a conventional photochromic layer made from a known photochromic photoresist containing the photochromic dyes, which was formed on the glass substrate by spin coating.

[0061] The curves show that the measurement curve 101 of the glass body exhibits a significantly higher microhardness according to one aspect of the present application and reaches a saturation value that is almost 100 N / mm² even at greater penetration depths. 2The value is higher than that of comparative example 102. It is also evident that, particularly in the initial penetration depth range, from 0 pm to approximately 1 m, the decrease in microhardness in measurement curve 101 is less pronounced than in comparative example 102. This demonstrates that, according to one aspect of the present application 101, the glass body 1 exhibits a higher microhardness than comparative example 102 not only at greater penetration depths of several micrometers, but also at shallower penetration depths. The glass body thus has an overall higher microhardness, verified across all measurement ranges, and therefore exhibits greater strength. Consequently, it is particularly suitable as a gas body for lenses and spectacle lenses of all kinds, as its higher microhardness results in improved everyday usability.In particular, by combining it with photochromic dyes in layer 4 formed on the substrate, a photochromic glass body 1 with improved microhardness and thus high suitability for everyday use can be produced. In the present disclosure, "has an X" does not generally imply an exhaustive list, but is a short form of "has at least one X" and also includes "has two or more X" as well as "has Y in addition to X".

[0062] The numerical values ​​indicated with "approximately" may preferably deviate by + / - 10% from the stated value, more preferably by + / - 5% from the stated value, more preferably by + / - 2% from the stated value, and in particular may be exactly the stated value. This applies to all numerical values ​​so designated in this application.

[0063] In the present disclosure, "essentially" with regard to the similarity of composition implies that two compositions are essentially identical if their principal components, which are understood to be those compounds contained in the composition, constitute a cumulative weight percentage of at least 60% of the composition. That is to say, two compositions are to be considered essentially identical in the present disclosure if they have the same principal components and their weight percentages in the composition differ by less than 20%, preferably by less than 10%, and particularly preferably by less than 5%. Irrespective of the foregoing, two compositions are considered essentially identical if the differences represent minor deviations, in particular those due to metrological or purity factors.

[0064] List of reference signs

[0065] 1, 1', 1" glass body

[0066] 2 basic shapes

[0067] 4-layer

[0068] 6 Buffer and / or hard lacquer coating

[0069] 8 Additional, further coating

Claims

Patent claims 1. Glass body (1 , 1', 1"), in particular spectacle lens, comprising: a base body (2) with a first and a second side, a layer (4) which is arranged on at least one side of the base body (2), wherein: the base body (2) is made of plastic glass with a microhardness HL, the layer (4) has a microhardness of Hc > 0.5 x HL and the layer (4) is formed by polymerization of a polymerizable composition which has at least one photochromic dye and as a surface additive at least one compound from the group of polyether (block) copolymers.

2. Glass body according to claim 1, wherein the layer (4) is arranged directly on the base body (2).

3. Glass body according to any of the preceding claims, wherein the layer (4) has a layer thickness of greater than or equal to 10 pm.

4. Glass body according to one of the preceding claims, wherein the base body (2) has a microhardness HL of greater than or equal to 100 N / mm². 2 and the layer (4) has a microhardness Hc greater than or equal to 60 N / mm² 2 The base body (2) particularly preferably has a microhardness HL of greater than or equal to 160 N / mm². 2 and the layer (4) has a microhardness Hc of greater than or equal to 120 N / mm² 2 on.

5. Glass body according to one of the preceding claims, wherein the layer (4) is formed by sprue.

6. Glass body according to any of the preceding claims, wherein the base body (2) and / or the layer (4) is made of poly(thio)urethane, acrylate, Polyacrylate, methacrylate, polymethyl methacrylate, polycarbonate, polydiethylene glycol bisallyl carbonate or combinations thereof are formed.

7. Glass body according to one of the preceding claims, wherein the base body (2) was formed by polymerization of a polymerizable composition and the polymerizable composition for forming the base body (2) comprises substantially the same substances or compounds as the polymerizable composition for forming the layer (4).

8. Glass body according to any of the preceding claims, wherein the difference An between the refractive index n L of the base body (2) and the refractive index n c of layer (4) at least at one wavelength, in particular determined at a wavelength of about 550 nm, An = \n L — n c | < 0.2 is.

9. Glass body according to one of the preceding claims, wherein the layer (4) is a, in particular permanently, colored layer (4) and the polymerizable composition of the layer (4) comprises at least one permanent dye.

10. Glass body according to one of the preceding claims, wherein at least one side of the base body (2) on which the layer (4) is arranged has at least one further layer or coating (8) arranged on the layer (4), wherein this is selected from: an anti-reflective coating; and / or a mirror coating; and / or an easy-to-clean coating; and / or an anti-static coating; and / or an anti-fog coating; and / or a UV protection coating; and / or an IR protection coating; and / or a blue light protection coating.

11. Glass body according to claim 10, wherein one of the following coatings (6) is arranged between layer (4) and at least one further coating (8): a buffer coating; and / or a hard coating.

12. Use of a glass body according to one of the preceding claims in lenses and glasses for spectacles of all kinds, such as corrective spectacles, driving glasses, ski goggles, sunglasses, motorcycle goggles, for visors of protective helmets and the like, or for sun protection purposes in vehicles or in the construction sector, in the form of windows, protective screens, covers, roofs and the like.

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