DE202024000846U1 - Photochromic vitreous body - Google Patents

Abstract

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 H _L ,
- the layer (4) has a microhardness of H _C = 0.5 × H _L and
- 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.

Description

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

Glass bodies, especially plastic lenses, preferably plastic spectacle lenses, are generally made from a polymerizable mixture or composition, which is often also referred to as a casting resin. Such a composition typically consists of plastic monomers and is in the form of a castable or moldable mass, which, for example, to produce a plastic lens, is poured into a volume formed between two molding parts arranged at a predetermined distance from one another. The structure is then cured by applying energy, i.e., the polymerizable composition or casting resin is polymerized, with the energy required for this process generally being provided by thermal energy.

In other areas as well, such as when providing plastic lenses with functional coatings, particularly with functional lacquers, these coatings or lacquers are usually applied as a polymerizable composition to the plastic lens to be coated, before solidification or curing takes place during a polymerization step. Such functional coatings generally have a lower hardness or microhardness than the underlying vitreous body or base body and can therefore be considered soft coatings in terms of their microhardness, particularly in comparison to the underlying base body. Such soft coatings have the disadvantage that they are not very strong and therefore do not offer sufficient protection against everyday external influences. Accordingly, they degrade quickly without an additional outer protective layer, which can be expressed in particular by a diminished effectiveness of their respective functionality.

The US 11/526 031 B2 describes an approach in which such a soft layer is protected by a hard protective layer, in particular one arranged over it. This can protect the soft layer from degrading external influences. However, this approach has the disadvantage that an additional (protective) layer must be applied, which on the one hand makes the manufacturing process more complex and more time- and material-intensive, and on the other hand leads to a hard-soft-hard structure consisting of a (relatively) hard base body, a soft functional coating, and then a hard (protective) layer. Due to different material properties, in particular differing hardnesses, such structures are generally undesirable and should be avoided.

Against this background, it is an object of one aspect of the present application to propose an improved glass body, in particular an improved spectacle lens, which does not have the above-mentioned disadvantages.

The object is achieved in particular by a glass body having the features of claim 1. The subclaims relate to advantageous developments.

• - einen Grundkörper (2) mit einer ersten und einer zweiten Seite,
• - eine Schicht (4), welche an zumindest einer Seite des Grundkörpers (2) angeordnet ist, wobei

der Grundkörper (2) aus Kunststoffglas mit einer Mikrohärte H_L ausgebildet ist, wobei die Schicht (4) eine Mikrohärte von Hc ≥ 0,5 × H_L aufweist und wobei die Schicht (4) durch Polymerisation einer polymerisierbaren Zusammensetzung (aus)gebildet ist, welche zumindest einen photochromen Farbstoff und als Oberflächenadditiv zumindest eine Verbindung aus der Gruppe der Polyether-(Block-)Copolymere aufweist.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 H _L , wherein the layer (4) has a microhardness of Hc ≥ 0.5 × H _L and wherein 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.

The base body is initially not further restricted, except that it has a first side and a second side arranged opposite the first side, wherein the first and second sides are connected to one another by an edge surface. The base body can have a flat shape, wherein the first and second sides are then substantially plane-parallel or parallel to one another. The base body can also have a shape deviating from this, in particular a shape in which at least one of the two sides has a non-parallel shape, in particular a curved shape. A curved shape can be described in more detail based on the existing radius of curvature, and a distinction is generally made between a first case in which a positive radius of curvature exists, wherein such a shape is also referred to as a convex shape, and a second case in which a negative radius of curvature exists, wherein such a shape is also referred to as a concave shape. Due to a non-parallel shape, such a base body is preferably suitable as Base body for a glass body, in particular for a lens glass body or a 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, imparts an optical effect to the glass body, in particular a reduction or magnification effect, whereby such a glass body can preferably be used as a lens or as a spectacle lens.

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 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.

In order to be suitable for later use as a lens, the base body should possess sufficient optical quality with regard to optical imaging properties. Those skilled in the art understand optical imaging properties to mean a multitude of determinable, characteristic quantities that can characterize a given object, in particular a base body, with regard to its optical imaging properties, including properties such as spectral transmission, color rendering, or the Abbe number. Particularly in the use of plastics as materials for producing lenses, in particular ophthalmic lenses or 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, in one embodiment, the base body comprises plastic; in particular, it can be a plastic base body, preferably a plastic base lens.

Depending on the plastic used, the base body can be formed, as described above, by polymerizing a polymerizable composition, for example, by curing under controlled temperature conditions or by irradiation with electromagnetic waves, particularly UV light. Furthermore, the base body can be formed by thermoplastic deformation, such as injection molding.

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

The microhardness of an object, particularly the base body and/or the layer, is generally determined by applying a known and well-defined test specimen to the object to be measured with a defined force, or, converted to the surface of the test specimen, with a defined pressure. The deformation observed upon penetration of the test specimen allows a conclusion to be drawn about the hardness. Particularly for penetration depths greater than or equal to approximately one-tenth of the layer thickness of the layer to be determined for hardness, it is important to note, according to the Bückle rule, that the composite hardness of the system is being measured and not the individual hardness of the layer. Such a hardness measurement can be performed using commercially available hardness measuring devices, such as the FISCHERSCOPE HM2000 from Helmut Fischer GmbH, Sindelfingen, for layers with a thickness of more than 1-2 µm, or the PICODENTOR HM500 from the same company for layers with a thickness of 1 µm or less.

The measurement and calculation of material parameters, such as microhardness or Martens hardness, elastic indentation modulus, indentation creep, and the ratio of elastic to plastic deformation, are carried out in accordance with DIN EN ISO 14577-1. Measurements can be performed with a maximum force of 300 mN, with the maximum force being reached after 20 seconds of measurement time, and the measurement is performed at 30°C. The microhardness can then be determined from the measurement when the maximum force is reached.

The base body preferably has a microhardness H _L of greater than or equal to 85 N/mm ² or 90 N/mm ² , preferably of greater than or equal to 95 N/mm ² , more preferably of greater than or equal to 100 N/mm ² , particularly preferably of greater than or equal to 150 N/mm ² , in particular of greater than or equal to 175 N/mm ² . A base body which has the above-mentioned microhardness is suitable as a base body for a glass body since it has a certain strength or toughness or wear resistance and thus good suitability for everyday use.

The glass body comprises (at least) one layer, which is 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 ply is arranged between the layer and the base body or is located therebetween. In a modification of this, the layer can also be arranged indirectly, which means that at least one, preferably two or more additional layers or plies of a material different from the layer and the base body are arranged or located therebetween. These can preferably be additional layers or plies that impart an additional property to the glass body, in particular the base body and/or the layer. For example, one or two or more additional layers or plies arranged between the base body and the layer can improve the adhesion between the base body and the layer or provide an additional property.

This layer is initially not further restricted; in particular, like the base body, it can be formed from a material that is transparent in the visible spectral range or from a material that is (at least partially) transmissive to visible light. This makes the layer particularly suitable as a layer for a glass body, in particular for a spectacle lens.

The layer preferably has a microhardness Hc of less than or equal to 1000 N/mm ² , preferably less than or equal to 500 N/mm ² , particularly 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 a base body or with which a base body is provided in order to protect it, in particular, from mechanical damage, such as scratching. Such high values for the microhardness of the layer are not desirable, since an environment that is not too hard or solid is required for (optional) functionalization of the layer, for example by dyes contained in the layer, in particular photochromic dyes.

The layer can in particular be a functional layer and impart properties, preferably (additional) functional properties, to the base body provided therewith. In this way, a glass body has additional properties that the base body does not have, i.e., by means of the layer, a base body can be provided or refined with additional properties in order to obtain a (coated) glass body which has the desired additional properties. The layer can preferably be colored. Alternatively or additionally, the layer can be more easily colorable 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 take place in an immersion bath.

The layer has a microhardness Hc which is greater than or equal to half the microhardness of the base body H _L , i.e. Hc ≥ 0.5 × H _L , preferably Hc ≥ 0.6 × H _L , particularly preferably Hc ≥ 0.70 × H _L . Because the layer has a microhardness which corresponds to at least half the microhardness of the base body, it is characterized by increased hardness compared to common layers and, associated with this, increased strength or toughness or wear resistance. Advantageously, this makes it possible to obtain a glass body which comprises a base body and a layer arranged directly or indirectly thereon, which layer imparts at least one additional property to the glass body and at the same time is not too soft. A soft layer within the meaning of the invention, in particular a layer which is too soft, has a microhardness of Hc < 0.4 × H _L. In particular, because the layer has a hardness greater than or equal to 50% of the hardness of the base body, a functional layer or coating can be realized without an additional protective layer, in particular one that protects the functional coating. Advantageously, this allows the creation of a (functionally coated) glass body that does not require an additional protective layer and is thus, on the one hand, cost-effective to produce and, on the other hand, particularly in the absence of an additional hard protective layer, does not have a hardness profile, comprising a hard base body, a soft layer, and then a hard protective layer.

The glass body is further characterized in that the layer is formed by polymerizing a polymerizable composition, wherein the polymerizable composition comprises a compound from the group of polyether (block) copolymers as at least one surface additive. Copolymers are polymers composed of two or more different monomer units. Block copolymers are made up of 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 composition for forming the layer, in addition to other components, in particular a photochromic dye, (photochromic) compounds or dyes can be embedded, which are then protected from degradation over time and which can exhibit their photochromic properties in a stable manner. Particularly in combination with photochromic dyes in the polymerizable composition, the polyether (block) copolymer ensures improved performance and improved properties of the photochromic dyes.

The layer is preferably formed by polymerizing a polymerizable composition. Advantageously, the layer can be formed or produced particularly favorably by preparing or providing a polymerizable composition because the polymerizable composition can first be applied to the base body in a simple manner and then polymerized on the base body by polymerization, thus forming a firm bond with it. Those skilled in the art are familiar with a number of common methods for applying a polymerizable composition, including, in particular, spray coating, spin coating, dip coating, or even sprue coating. This allows the layer to be formed particularly favorably, particularly in the case of a base body that has at least one curved side. For forming the layer by polymerization of the polymerizable composition, the person skilled in the art is also familiar with common methods, in particular thermal polymerization, triggered or caused by supplying or exposing the composition to heat, as well as UV-induced polymerization, triggered or caused by the presence of or irradiation of the polymerizable composition with UV radiation, or a combination thereof.

A preferred polymerizable composition comprises, as 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 suitability for everyday use. Also preferred are polymerizable compositions comprising, as main components, di- and/or trifunctional (meth)acrylates, which are particularly suitable for forming a polymethyl (meth)acrylate layer. Such layers are also known for their good optical properties combined with high suitability for everyday use. In addition to the preferred main components mentioned above, such polymerizable compositions may also comprise further components, in particular various additives, which fulfill additional functions or can specifically modify the chemical and/or mechanical properties of such a polymerizable composition. It may also be advantageous to add additives such as light and/or radical stabilizers in order to improve the resistance of such a layer, in particular to environmental influences and climatic conditions.

The layer preferably has a thickness of greater than or equal to 10 µm, preferably greater than or equal to 30 µm, particularly preferably greater than or equal to 50 µm, but in particular less than or equal to 350 µm or less than or equal to 750 µm. This advantageously allows for the formation of a comparatively thin layer, in particular a very thin layer compared to the base body. In this way, the amount of material required can be advantageously reduced.

Preferably, the base body has a microhardness H _L of greater than or equal to 85 N/mm ² and the layer has a microhardness Hc of greater than or equal to 43 N/mm ² , preferably greater than or equal to 50 N/mm ² . Further preferably, the base body has a microhardness H _L of greater than or equal to 100 N/mm ² and the layer has a microhardness Hc of greater than or equal to 60 N/mm ² , particularly preferably the base body has a microhardness H _L of greater than or equal to 160 N/mm ² and the layer has a microhardness H _C of greater than or equal to 120 N/mm ² . Combinations of base body and layer which meet the above-mentioned values are characterized by particularly high suitability for everyday use as glass bodies or spectacle lenses and can be produced in particular using known plastic glass materials familiar to those skilled in the art.

Preferably, the layer is formed by casting, i.e., the layer is produced in particular by a casting process, wherein the base body is first arranged at a distance from a mold shell to form a cavity, the resulting cavity is sealed accordingly, and the cavity is subsequently filled with the polymerizable composition to form the layer. Advantageously, base bodies can be reproducibly provided with a particularly thin layer in this way, in particular a layer having a layer thickness of less than 750 µm.

Preferably, the polymerizable composition for forming the layer at least one crosslinker. This can advantageously promote the formation of crosslinks during polymerization, as a result of which the formed layer has a greater microhardness. Preferably, by adding compounds from the group of multifunctional thiols or multifunctional alcohols, microhardness values for the formed layer of Hc ≥ 0.9 × H _L , more preferably Hc ≥ 1.0 × H _L , particularly preferably Hc ≥ 1.1 × H _L can be achieved. In addition, inorganic or organic nanoparticles which have been surface-modified with thiols or alcohols can be used. Furthermore, multifunctional isocyanates or inorganic or organic nanoparticles modified with isocyanates can be used. In other words, this makes it possible to form a layer which has excellent strength and, in particular, has a microhardness which approximately corresponds to the hardness of the base body and, in further developments thereof, is even higher.

The base body of the glass body is preferably 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 the person skilled in the art, particularly commercially available plastic materials for transparent lens bodies, can be used. 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.

Preferably, the base body has been produced or formed by polymerizing a polymerizable composition, wherein the polymerizable composition of the base body comprises essentially the same substances or compounds as the polymerizable composition for forming the layer. Advantageously, by selecting a composition that is as similar as possible, preferably very similar, particularly preferably essentially identical, of the respective polymerizable compositions of the base body and layer, on the one hand, a particularly strong and long-lasting adhesion between the base body and layer can be achieved. On the other hand, this also makes it possible to achieve very comparable optical properties, due to essentially the same substances or compounds, resulting in a glass body characterized by low interference phenomena. Further advantageously, the sprue layer can be colored essentially or exactly like the base body, so that no disturbing optical effects arise due to different colors.

Preferably, the difference Δn between the refractive index n _L of the base body and the refractive index n _C of the layer is, at least at one wavelength, in particular determined at a wavelength of approximately 550 nm, Δn = |n _L - n _C | ≤ 0.2. Preferably, the difference Δn = |n _L - n _C | ≤ 0.1. Further preferably, the difference Δn = |n _L - n _C | ≤ 0.01, particularly preferably Δn = |n _L - n _C | ≤ 0.001, in particular Δn = |n _L - n _C | ≤ 0.0001 and thus approximately identical. Interference phenomena that arise at interfaces with different refractive indices can advantageously 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, 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 or approximately 1.6 or approximately 1.67 or approximately 1.72 or approximately 1.74, where the term "approximately" can refer to a deviation of less than 5%, preferably less than 1%.

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 body, i.e., the glass body has acquired an additional property by providing the base body with a photochromic layer, in particular photochromic behavior, which is understood in particular to mean 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 the irradiation with UV light decreases, the photochromic dye returns to its original molecular structure and thus also its original absorption behavior. A photochromic dye thus enables reversible switching back and forth between a dark and a light tint. Naphthopyrans, spirooxazines and/or spiropyrans are particularly suitable as photochromic dyes, which, on the one hand, have a rapid darkening behavior and, on the other hand, a high durability. In particular, the polymerizable composition can not only contain a photochromic dye from the above-mentioned compound groups on They can have not only one, but also two or more, whereby the selected photochromic dyes can also be different. Using such a composition supplemented with photochromic dyes, a photochromic layer can be formed on a base body or a photochromic glass body can be obtained, which can preferably be used as a self-tinting spectacle lens and is very comfortable to wear, since the self-tinting effect makes switching between conventional prescription glasses, for example, reading glasses, and sunglasses obsolete.

The layer is preferably colored, in particular permanently colored, and the polymerizable composition of the layer comprises at least one permanent dye. Permanent means, particularly in contrast to photochromic, that the dye has a constant absorption behavior and cannot reversibly switch between an excited (absorbing) and a non-excited (non-absorbing) state due to UV radiation. 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. A composition modified in this way then has a pre-coloration as a new or additional property or, with respect to a composition without dye, a different transmission characteristic. This results in, in particular, in a colored composition, whereby a colored layer is advantageously formed on the base body or a colored glass body is obtained. These are preferably azo dyes, cyanine dyes, anthraquinone dyes, or the like, as are frequently used in the conventional coloring of glass bodies, especially plastic spectacle lenses. In particular, the polymerizable composition can comprise not just one dye from the aforementioned groups of compounds, but also two or more, whereby the selected dyes can, in particular, also be different. The skilled person routinely selects a suitable dye or a mixture of suitable dyes.

In a further development thereof, the layer is preferably photochromic and, in particular, permanently colored. By combining these two forms, a permanently pre-colored layer can be obtained which has a first absorption characteristic or a first transmission behavior and, upon irradiation with UV radiation, a different second absorption characteristic or a different second transmission behavior. Advantageously, by providing a base body with such a layer, a body with a permanent coloration and photochromic behavior can be obtained, which thereby has special properties, such as a first darkening and, in a further development, a second, even deeper darkening upon irradiation with UV radiation. Such a glass body is therefore particularly suitable for use as a sunglass lens, which has a first darkening and, upon exposure to UV radiation, in particular that present in the sunlight spectrum, a second, even deeper darkening.

• - eine Entspiegelungsbeschichtung; und/oder
• - eine Verspiegelungsbeschichtung; und/oder
• - eine Easy-to-Clean-Beschichtung; und/oder
• - eine Antistatik-Beschichtung; und/oder
• - eine Anti-Beschlag-Beschichtung; und/oder
• - eine UV-Schutz-Beschichtung; und/oder
• - eine IR-Schutz-Beschichtung; und/oder
• - eine Blauschutz-Beschichtung.

Preferably, the glass body has at least one further layer or coating on at least the side, or in a further development thereof on both sides, on which the layer is arranged, which is selected from:

• - an anti-reflective coating; and/or
• - a mirror coating; and/or
• - an easy-to-clean coating; and/or
• - an antistatic coating; and/or
• - an anti-fog coating; and/or
• - a UV protection coating; and/or
• - an IR protection coating; and/or
• - a blue protection coating.

The expert knows how to skillfully combine the above-mentioned coatings in order to obtain glass bodies with different properties.

Preferably, the at least one further layer is an anti-reflective coating. Such a coating, comprising at least one individual layer, generally preferably comprising alternating individual 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 for at least one wavelength of incident light, preferably for two or more, particularly preferably for a plurality of wavelengths of incident light, by means of destructive interference. Advantageously, this results in an anti-reflective glass body, which is particularly suitable as a lens and/or spectacle lens, since the anti-reflective coating renders it (largely) free from disruptive reflection phenomena and is characterized by high transmission.

Preferably, and in particular alternatively or in addition to an anti-reflective coating, the at least one further layer is a mirror coating. Such a coating, comprising at least one individual layer, generally preferably comprising alternating individual 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, in order to reflect the incident light by means of constructive interference for at least one wavelength of incident light, preferably for two or more, particularly preferably for a plurality of wavelengths of incident light. Advantageously, this results in a mirrored glass body which is particularly suitable as a mirrored lens and/or mirrored spectacle lens, in particular a sunglasses lens, since it reflects the light emitted by the mirror coating.

Preferably, and in particular alternatively or in addition to an anti-reflective and/or mirror coating, the at least one further layer is an easy-to-clean coating, which is characterized by having a low surface energy and, in particular, hydrophobic and/or oleophobic properties, which result in a glass body provided therewith having a lower tendency towards the adhesion of dirt, grease and/or water. Such a coating often also has an additional property of improved cleanability. Advantageously, this makes it possible to obtain a glass body that is highly suitable for everyday use, has a high resistance to everyday, grease- and/or water-based soiling, and is easy to clean. Such an easy-to-clean coating can also be arranged as the final, outermost layer as part of a multilayer (interferometric) coating system.

Preferably, and in particular alternatively or in addition to an anti-reflective and/or mirror coating and/or easy-to-clean coating, the at least one further layer is an antistatic coating which, in particular, counteracts static charging of the glass body in order to thus 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 preferably used, in particular substoichiometric metal oxides, which thereby exhibit conductivity. Such an antistatic coating can also be arranged as part of a multilayer (interferometric) layer system or be present therein.

Preferably, and in particular alternatively or in addition to an anti-reflective and/or mirror 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 the fact that it counteracts the formation of fog. This is understood in particular to mean that it counteracts the formation of (water) droplets upon condensation of the water vapor contained in the air (particularly during temperature changes from a cold environment to a warm environment), in order to ensure that no individual droplets form, but rather a largely uniform film that enables acceptable transparency or transmission. This advantageously makes it possible to obtain a glass body, in particular a spectacle lens, that is highly comfortable to wear. Such an anti-fog coating can also be arranged as a final, outermost layer as part of a multilayer (interferometric) coating system.

Preferably, and in particular alternatively or in addition to an anti-reflective and/or mirror coating and/or easy-to-clean coating and/or antistatic coating and/or anti-fog coating, the at least one further layer is a UV protection coating, which is characterized by reduced transmission behavior with respect to UV radiation, preferably by inhibited to completely absorbing transmission behavior or reflective behavior with respect to UV radiation. This advantageously results in a glass body which has a blocking effect with respect to the transmission of (harmful) UV radiation and is thus particularly suitable as a lens or spectacle lens. In a lens, such UV protection can be advantageous in order to protect sensitive components, e.g., optical sensors, from irradiation or exposure to UV radiation. In a spectacle lens, protection against harmful UV radiation is advantageous in order to protect the eyes of the wearer. Such a UV protection coating can also be arranged as part of a multi-layer (interferometric) coating system or a corresponding coating system, optionally an anti-reflective and/or mirror coating, can be designed so that it suppresses light in the visible spectral range (anti-reflective coating) or deliberately reflects it (mirroring). tion) and at the same time has increased absorption or reflection of UV radiation.

Preferably, and in particular alternatively or in addition to an anti-reflective and/or mirror coating and/or easy-to-clean coating and/or antistatic 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. This advantageously results in a glass body which has a blocking effect with respect to the transmission of (harmful) IR radiation and is thus particularly suitable as a lens or spectacle lens. In a lens, such IR protection can be advantageous for protecting sensitive components, e.g., optical sensors, from exposure to IR radiation, and in particular for reducing, inhibiting, or preventing the associated thermal energy input. In the case of spectacle lenses, protection against harmful IR radiation is advantageous in order to protect the eyes of the wearer. Such an IR protection coating can also be arranged as part of a multi-layer (interferometric) coating system, or a corresponding coating system, optionally an anti-reflective and/or mirror coating, can be designed such that it suppresses light in the visible spectral range (anti-reflective coating) or deliberately reflects it (mirroring) and at the same time has increased absorption or reflection of IR radiation. In a further development of this, an IR protection coating can also be designed in combination with a UV protection coating, in particular as a multi-layer (interferometric) coating system, and thus has advantageous protection against radiation from both radiation ranges adjacent to the visible spectrum. This can preferably be achieved by suitable design of a multi-layer (interferometric) coating system.

Preferably, and in particular alternatively or in addition to an anti-reflective and/or mirror coating and/or easy-to-clean coating and/or antistatic 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-protection coating, which is understood to be a coating that exhibits increased absorption and/or reflection of radiation from the blue spectral range. This advantageously 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-shielding coating can also be arranged as part of a multilayer (interferometric) coating system, or a corresponding coating system, optionally an anti-reflective and/or mirror coating, can be designed so that it suppresses light in the visible spectral range (anti-reflective coating) or deliberately reflects it (mirroring coating), while simultaneously exhibiting increased absorption or reflection of IR radiation. In a further development of this, a blue-shielding coating can also be combined with a UV-shielding and/or IR-shielding coating, in particular as a multilayer (interferometric) coating system, thereby providing advantageous protection against radiation from the aforementioned spectral ranges.

It goes without saying that the person skilled in the art selects any combination, in particular synergistic combinations, from the above-mentioned coatings in order to obtain a glass body which has a base body and the layer, as well as any number of further layers for obtaining further advantageous properties.

• - eine Pufferlackbeschichtung; und/oder
• - eine Hartlackbeschichtung.

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 list mentioned above:

• - a buffer lacquer coating; and/or
• - a hard lacquer coating.

By placing a buffer lacquer coating between the layer and at least one other layer, the fracture strength of the glass body coated in this way can be improved or increased. It is known that such buffer lacquer layers are generally formed as incompletely polymerized layers and thus help the glass body achieve improved fracture strength. Such buffer lacquer coatings are particularly advantageous when base bodies made of comparatively hard plastic glass materials, such as poly(thio)urethane and/or polymethyl methacrylate, as glass bodies or spectacle lenses, are required to meet special fracture strength requirements, such as those required by the US Food and Drug Administration (FDA) for the drop ball test.

By arranging a hard lacquer coating between the layer and at least one further layer, the mechanical strength, in particular the scratch resistance, of the glass body can be improved. In particular, compared to mineral glass, base bodies made of plastic glass have lower scratch resistance and are prone to increased scratching in everyday use, particularly as glass bodies or spectacle lenses. In order to obtain a more resistant glass body, such a hard lacquer coating is arranged or formed as an additional coating, which preferably consists of siloxanes and thus has increased scratch resistance. In a further development of this, by combining a buffer lacquer and a hard lacquer coating, a particularly resistant glass body can be obtained which has both increased fracture strength and increased scratch resistance and is therefore particularly suitable as a lens or spectacle lens.

One aspect relates to the use of a glass body according to the invention in lenses and glasses for spectacles of all kinds, such as, for example, corrective spectacles, driving spectacles, 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 visors, covers, roofs and the like.

• - 1 eine erste Ausführungsform des Glaskörpers; und
• - 2 eine zweite Ausführungsform des Glaskörpers aufweisend optionale Merkmale; und
• - 3 eine dritte Ausführungsform des Glaskörpers.
• - 4 ein schematisches Diagramm Mikrohärtemessungen

The invention is described in more detail below with reference to 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 appended claims. Like reference numerals indicate like or recurring elements. They show:

• - 1 a first embodiment of the glass body; and
• - 2 a second embodiment of the glass body having optional features; and
• - 3 a third embodiment of the glass body.
• - 4 a schematic diagram of microhardness measurements

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.

The base body 2 is a base body formed from polythiourethane as the preferred plastic lens material. The base body was formed from a polymerizable composition, also referred to as a casting resin mixture, wherein the polymerizable composition has isocyanates and isocyanate-reactive components as its main components, wherein isocyanate-reactive components are understood to mean, in particular, thiols or alcohols with two or more functional groups, i.e., SH or OH groups. Plastic lenses made of polythiourethane are highly suitable for everyday use, coupled 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 also preferably suitable as a base body for spectacle lenses, which can also very effectively correct (slightly) higher refractive errors, expressed in spherical equivalents of more than +/- 3.0 dpt, with an acceptable lens (center) thickness, which offers particular aesthetic advantages. The base body 2 can be manufactured as a polythiourethane cast, using a correspondingly curved mold, so that the resulting base body 2 already has a curved shape on one side, expressed as a base curve (BK), of BK = 3.0. The base body 2 can have a microhardness of approximately 180 N/ ^mm² .

The resulting base body 2 and a further mold shell can then be arranged at a distance from one another, so that a cavity is formed between the curved first side of the base body 2 and the spaced-apart mold shell, which cavity can be sealed using 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 can have isocyanates and isocyanate-reactive components as further preferred main components. In addition to these main components, the composition can also contain photochromic dyes, in particular naphthopyran dyes as preferred photochromic dyes. In this way, using the method described above, which is also referred to as the gating method, a layer 4, in particular a photochromic layer, can be formed, in particular directly, on the base body, which layer can have a layer thickness of approximately 30 µm to approximately 400 µm, in particular approximately 300-350 µm.

The (photochromic) layer 4 formed directly on the base body can have a microhardness of approximately 130 N/mm ^2. As a result, By providing the base body 2 with a photochromic layer 4, a glass body 1 was obtained which has photochromic properties. The glass body 1 thus obtained accordingly has a base body 2, which has acquired an additional property through the functional layer 4 formed directly thereon in this embodiment. With a microhardness (Martens hardness) of approximately 130 N/mm ² , the layer 4 has a microhardness which corresponds to approximately 70% of the microhardness of the base body 2 and thus has a microhardness which is significantly more than half the microhardness of the base body 2 and thus has above-average strength. The resulting glass body 1 can be processed as a semi-finished part in further, downstream production steps, for example, by one- or two-sided surface processing to achieve a desired optical effect, optionally by a hard lacquer coating for even greater scratch resistance, or optionally by an anti-reflective coating for higher transmission, and thus be further processed into a coated lens or a coated spectacle lens. Preferably, only one-sided (machining) surface processing is carried out on the side of the base body 2 facing away from layer 4.

It goes without saying that the layer 4 can also be formed on the base body 2 using any other method. Likewise, the layer 4 can be formed from a different material; for example, instead of polythiourethane, it can also be formed from a polymerizable composition comprising, for example, functional (meth)acrylates, in particular non-cyclic bi- and/or trifunctional methacrylates or acrylates, which are preferably suitable for forming a (thermosetting) layer 4 made of polymethyl methacrylate or polyacrylate having a refractive index of approximately 1.54 determined at a wavelength of approximately 550 nm.

It is also understood that the photochromic dyes added to the polymerizable composition for forming layer 4 in the above-described embodiment represent only one 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 thereby obtain a layer 4 with corresponding functions, whereby a glass body 1 comprising a base body 2 provided with such a layer 4 receives the corresponding functions.

2 shows a second embodiment of a glass body 1, wherein the starting product is a glass body 1 as a semi-finished part, as in 1 described, can serve.

The glass body 1 thus obtained can be provided with further layers as a semi-finished part in subsequent production steps.

The glass body 1' was first coated with a hard lacquer as a preferred buffer and/or hard lacquer coating 6 during a dip coating process. This increased the scratch resistance of the glass body 1', and it now has greater everyday usability because it is better protected against (light) scratches.

Subsequently, a multi-layer anti-reflective coating was formed on the glass body 1' as a preferred further coating 8. This anti-reflective coating was formed by vapor deposition in a dedicated high-vacuum coating system, wherein, in such a system, low-refractive and high-refractive coating materials are alternately evaporated by means of an electron beam, and the vapor deposition is deposited as alternating, thin layers on the glass body 1', in particular on the surface of the formed hard lacquer coating 6.

In this way, an anti-reflective, hard lacquer coated glass body 1' was obtained, which has an increased scratch resistance due to the formed hard lacquer coating and a high suitability for everyday use due to the anti-reflective coating, due to a high transmittance and the absence of disturbing reflections or residual reflections.

3 shows a third embodiment of a glass body 1, which in particular differs from the glass body 1 1 differs because the glass body 1" has a layer 4 on the first and second side of its base body 2, i.e., on both sides. This allows an improved or increased functionalization of the glass body 1" to be achieved. In particular, in a further development thereof, a first and a second functionalization can be achieved by different layers 4 on the first and second side of the base body 2. In the case of identical layers 4 on the first and second side of the base body 2, this layer 4 can preferably be formed by dip coating, wherein the base body 2 is immersed, in particular multiple times or repeatedly, in an immersion bath containing the polymerizable composition to form the layer 4, wherein upon immersion, a thin film of the polymerizable composition adheres to both sides of the base body 2. By repeating this process several times until the desired layer thickness of the layer 4 is reached and subsequent polymerization, optionally by heat (thermal) or by UV radiation (UV-induced), results in a solidified formation of the layer 4. In particular for a layer 4 to be formed on both sides of the base body 2, dip coating is a particularly advantageous manufacturing process.

4 shows a schematic diagram of microhardness measurements (plotted on the abscissa) at a corresponding penetration depth (plotted as the ordinate) for microhardness measurements on glass bodies. The glass bodies to be measured were placed in a FISCHERSCOPE HM2000 microhardness measuring device from Helmut Fischer GmbH. For the microhardness measurement, a test specimen with a defined geometry was pressed into the glass body to be measured with a force of approximately 300 mN (milli-Newtons). The measuring device determines the resulting microhardness from the deformation of the glass body resulting from the pressing of the test specimen, depending on the penetration depth of the test specimen.

The solid line 101 shows the microhardness-penetration depth curve of a glass body 1 made of 1 which has a polythiourethane base body 2 and a photochromic layer 4 formed thereon, also comprising polythiourethane.

A comparative example is shown as the dotted line 102. This is also a polythiourethane base body, but it has a conventional photochromic layer made from a known photochromic photoresist containing the photochromic dyes and formed by spin coating on the glass body.

It can be seen from the curve progressions that the measurement curve 101 of the glass body according to one aspect of the present application has a significantly higher microhardness and even at greater penetration depths reaches a saturation value which is almost 100 N/mm ² higher than that of the comparative example 102. It can also be seen that, particularly in the first range of the penetration depth, in the range of a penetration depth of 0 µm to approximately 1 µm, the drop in microhardness in the measurement curve 101 is smaller or weaker or not as pronounced as in the comparative example 102. It can therefore be seen that the glass body 1 according to one aspect of the present application 101 not only has a higher microhardness than the comparative example 102 at greater penetration depths of several micrometers, but also has a higher microhardness even at shallow penetration depths. The glass body thus has a higher overall microhardness, verified across all measurement ranges, and thus exhibits greater strength. It is therefore ideally suited as a gas body for lenses and spectacle lenses of all types, as this higher microhardness improves everyday usability. In particular, by combining it with photochromic dyes in layer 4 formed on the base body, a photochromic glass body 1 with improved microhardness and thus high everyday usability can be produced.

In the present disclosure, "has an X" generally does not imply an exhaustive list, but is a shortened form of "has at least one X" and also includes "has two or more Xs" and "has Y in addition to X."

The numerical values indicated with "approximately" may preferably deviate by +/- 10% from the stated value, particularly preferably by +/- 5% from the stated value, particularly 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.

In the present disclosure, "essentially" with regard to the similarity of composition implies that two compositions are essentially identical if their main constituents, which are understood to mean those compounds contained in the composition which, when added together, constitute a percentage by weight of at least 60% of the composition. This means that in the present disclosure, two compositions are essentially identical if they have the same main constituents and their percentage by weight in the composition differ by less than 20%, preferably less than 10%, particularly preferably less than 5%. Irrespective of this, two compositions are essentially identical if the differences represent minor deviations, in particular due to measurement technology or purity.

List of reference symbols

1.1',1"

vitreous body

2

Basic body

4

layer

6

Buffer and/or hard lacquer coating

8

Additional, further coating

QUOTES CONTAINED IN THE DESCRIPTION

This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 11/526 031 B2 [0004]

Claims (12)

Glass body (1, 1', 1"), 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 H _L , - the layer (4) has a microhardness of H _C = 0.5 × H _L and - the layer (4) is formed by polymerizing 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. Glass body according to claim 1, wherein the layer (4) is arranged directly on the base body (2). Glass body according to one of the preceding claims, wherein the layer (4) has a layer thickness of greater than or equal to 10 µm. Glass body according to one of the preceding claims, wherein the base body (2) has a microhardness H _L of greater than or equal to 100 N/mm ² and the layer (4) has a microhardness Hc of greater than or equal to 60 N/mm ² , particularly preferably the base body (2) has a microhardness H _L of greater than or equal to 160 N/mm ² and the layer (4) has a microhardness Hc of greater than or equal to 120 N/mm ² . Glass body according to one of the preceding claims, wherein the layer (4) is formed by casting. Glass body according to one of the preceding claims, wherein the base body (2) and/or the layer (4) is formed from poly(thio)urethane, acrylate, polyacrylate, methacrylate, polymethyl methacrylate, polycarbonate, polydiethylene glycol bisallyl carbonate or combinations thereof. 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). Glass body according to one of the preceding claims, wherein the difference Δn between the refractive index n _L of the base body (2) and the refractive index n _C of the layer (4) at least at one wavelength, in particular determined at a wavelength of approximately 550 nm, is Δn = | n _L - n _C | ≤ 0.2. 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. Glass body according to one of the preceding claims, wherein the 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 antistatic coating; and/or - an anti-fog coating; and/or - a UV protection coating; and/or - an IR protection coating; and/or - a blue protection coating. Vitreous body after Claim 10 , wherein one of the following coatings (6) is arranged between layer (4) and at least one further coating (8): - a buffer lacquer coating; and/or - a hard lacquer coating. Use of a glass body according to one of the preceding claims in lenses and glasses for spectacles of all kinds, such as, for example, corrective spectacles, driving spectacles, 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.