Double-sided processing method of watch lens embedded mark

Abstract

The invention discloses a double-sided processing method for a watch lens embedded mark, and belongs to the technical field of clock processing. The method comprises the following steps: performing laser etching on a user surface of a watch lens to form scribed lines or numbers; printing an annular window area on the back of the lens to enable the projection of the laser etching pattern to be located in a window; silk-screening an annular ink layer on the user surface to fill the laser etching area; and finally, excessive ink on the surface is removed through polishing, the ink embedded in the laser etching structure is reserved, and the wear-resistant and high-contrast embedded identifier is formed. According to the method, high precision of laser etching and visual enhancement of ink filling are combined, identification ink is prevented from being directly exposed to the surface, the abrasion resistance, the adhesive force and the pattern definition of the identification are remarkably improved, and the method can be widely applied to manufacturing of high-end intelligent watches and mechanical watches.

Description

Technical Field

[0001] This invention relates to the field of watchmaking technology, and in particular to a double-sided processing method for embedding markings inside a watch lens. Background Technology

[0002] In the design and manufacturing process of watches, clock markers and / or numerical markings are typically placed on the front cover crystal to help users accurately read the time. Currently, the industry commonly uses screen printing or pad printing processes to prepare these markings on the surface of the watch crystal.

[0003] However, this type of traditional surface printing technology has many technical defects in practical applications, making it difficult to meet the requirements of high-end watches for durability, accuracy, and aesthetics in markings. Firstly, it has poor abrasion resistance: the ink layer formed by screen printing or pad printing is a thin layer attached to the substrate surface, typically only about 0.015mm thick. During daily wear, watch crystals are easily rubbed or accidentally scratched by clothing, tabletops, walls, and other objects, causing wear, scratches, or even partial peeling of the surface ink layer, resulting in blurred or completely disappeared characters, seriously affecting the readability and lifespan of the product. Secondly, it has insufficient adhesion: watch crystals often use smooth, non-porous materials such as sapphire glass, ceramics, or highly polished metals as substrates. These materials have low surface energy, making it difficult for the ink to form a strong physical or chemical bond. When the material expands and contracts due to temperature and humidity changes, or is subjected to mechanical stress, the ink layer is prone to peeling off from the edges, eventually leading to complete delamination and marking failure. Secondly, the fineness of the pattern is limited: screen printing and pad printing processes rely heavily on the operator's experience in machine setup, and printing defects such as character distortion, ink loss, and rough edges are prone to occur during the printing process. Especially for extremely fine lines or tiny characters, the edge clarity and outline sharpness are difficult to achieve the ideal level, and the overall visual effect is inferior to patterns formed by high-precision processing methods such as laser engraving.

[0004] In summary, existing surface printing-based marking processes have significant shortcomings in terms of durability, adhesion reliability, and graphic accuracy, and a new processing method is urgently needed to improve the overall performance of watch crystal markings. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a double-sided processing method for embedded markings on watch lenses, in order to improve the durability, adhesion reliability and graphic accuracy of the markings on the user side, in view of the above-mentioned defects of the prior art.

[0006] To achieve the above objectives, the present invention provides a double-sided processing method for embedding markings within a watch lens, the method comprising the following steps:

[0007] Step S1: Based on the design drawings, laser engrave the user face of the watch lens to form engraved lines or numerical markings;

[0008] Step S2: Print a ring-shaped window area on the back of the watch lens opposite to the user's side, wherein the laser-engraved lines or numbers are projected onto the back side and fall completely into the ring-shaped window area.

[0009] Step S3: A ring-shaped ink layer is formed on the user side using a screen printing process. The ring-shaped ink layer covers and fills the engraved lines or numbers. The thickness of the ring-shaped ink layer is greater than the depth of the engraved lines or numbers.

[0010] Step S4: Remove the annular ink layer outside the engraved lines or numbers by mechanical polishing, leaving the ink filling the engraved lines or numbers to form an embedded identification structure.

[0011] In the double-sided processing method for embedding markings in watch lenses according to the present invention, in step S1, the watch lens is an unstrengthened white glass sheet after edge grinding.

[0012] In the double-sided processing method for embedded markings on watch lenses described in this invention, between step S1 and step S2, the method further includes:

[0013] Chemical strengthening treatment is applied to watch lenses that have undergone laser engraving.

[0014] In the double-sided processing method for embedded markings on watch lenses according to the present invention, in step S1, the depth of laser engraving is 0.04mm ± 0.01mm.

[0015] In the double-sided processing method for embedded markings on watch lenses described in this invention, in step S1, the laser engraving process parameters include scanning speed, laser frequency, and output power. The process parameters are set according to the target laser engraving depth, tilt angle, and graphic size.

[0016] In the double-sided processing method for embedded markings on a watch lens according to the present invention, step S2, after printing the annular window area, further includes the following sub-steps:

[0017] The back is printed with markings;

[0018] The lens with the aforementioned annular window area and markings is subjected to a heat-curing process.

[0019] In the double-sided processing method for embedded markings on watch lenses according to the present invention, step S3, after forming the annular ink layer, further includes:

[0020] The watch lens is placed in a vacuum defoaming machine for defoaming treatment to eliminate bubble defects in the ink layer.

[0021] In the double-sided processing method for embedded markings on watch lenses according to the present invention, in step S4, the polishing medium used for mechanical polishing includes pure water, and also includes at least one of a sponge polishing pad or a carpet polishing pad.

[0022] The present invention has the following beneficial effects:

[0023] This invention relates to a watch lens processing method that uses laser engraving to create a groove structure, followed by screen printing an ink layer onto the user side of the watch lens. The ink fills the grooves, and excess ink is removed from the user side surface through polishing, resulting in the ink-filled logo being completely embedded beneath the lens surface. This method avoids direct exposure of the ink layer to external friction, fundamentally solving the problems of easy wear, scratches, and peeling associated with traditional surface printing, and significantly extending the lifespan of the logo. Laser engraving offers sub-micron level processing precision, enabling high-fidelity molding of extremely fine lines and complex characters with sharp edges and no burrs. Compared to screen printing / pad printing, which relies on manual machine adjustments, this method offers better graphic consistency, eliminates defects such as ink gaps and burrs, and provides a superior visual effect. Laser engraving parameters can be precisely controlled, and the screen printing and polishing processes are mature and stable. The overall process is easily automated and suitable for mass production, making it ideal for large-scale manufacturing of high-end watches. Attached Figure Description

[0024] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0025] Figure 1 This is a schematic diagram illustrating the steps of a double-sided processing method for embedding markings in a watch lens, as provided in an embodiment of the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] The general idea of ​​this invention is as follows: laser engraving is performed on the user side of the watch lens to form engraved lines or numbers; then, a ring-shaped ink layer is screen-printed on the user side to fill the laser-engraved area; finally, the excess ink on the surface of the user side is removed by polishing, retaining the ink embedded in the laser-engraved structure to form a wear-resistant, high-contrast embedded logo. The user side mentioned in this article refers to the side facing the wearer.

[0028] The embodiments of the present invention will now be described in further detail with reference to the accompanying drawings. It should be understood that the embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0029] This invention is applicable to the processing of front cover plates for 2D and 3D watches.

[0030] like Figure 1 As shown, this embodiment of the invention provides a double-sided processing method for embedding markings within a watch lens, the method comprising the following steps:

[0031] Step S1: Based on the design drawings, laser engrave the user face of the watch lens to form engraved lines or numerical markings.

[0032] In this embodiment of the invention, before step S1, the method further includes: creating design drawings based on product requirements. The design drawings include information such as the shape of the watch lens, the position and size of the engraving lines or numerals. For example, some designs only require one engraving line at the 0, 3, 6, and 9 o'clock positions, or one engraving line at each hour position, or Arabic or Roman numerals to mark the clock positions. The watch lens may be 2D or 3D; for 2D structures, it may be round or square. A DXF file needs to be created based on the product structure and marking requirements. Then, the DXF file is imported into the laser engraving machine, the product is fixed to the machine base, the laser processing parameters are set, and then the laser engraving process is started.

[0033] In some embodiments of the present invention, in step S1, the laser engraving process parameters include scanning speed, laser frequency and output power, and the process parameters are set according to the target laser engraving depth, tilt angle and graphic size.

[0034] Laser engraving offers high precision and simple operation, making it suitable for large-scale production applications. Theoretically, laser engraving can create characters of any shape and depth, with the actual shape and depth determined by product requirements. In some embodiments of this invention, the laser engraving depth in step S1 is 0.04mm ± 0.01mm.

[0035] In some embodiments of the present invention, in step S1, the watch lens is an unreinforced white glass sheet that has undergone edge grinding. Between step S1 and step S2, the following is also included:

[0036] Chemical strengthening treatment is applied to watch lenses that have undergone laser engraving.

[0037] In this embodiment of the invention, chemical strengthening is performed using a molten salt bath of KNO3, NaNO3, or a combination of KNO3 and NaNO3. Taking KNO3 as an example, the laser-engraved watch lens is immersed in a high-temperature molten KNO3 salt bath, where the small-sized Na atoms on the lens surface... + Ions are large-sized K ions in molten salt + Ion replacement; due to K + The ion is larger in size, and it "squeezes" into the Na+. + After the lattice positions are left, compressive stress will be formed on the glass surface, typically at a depth of 20–100 μm.

[0038] In this embodiment of the invention, after laser engraving, the watch crystal is first cleaned, and then chemically strengthened. The reason for performing laser engraving before chemical strengthening is as follows:

[0039] (1) Laser engraving on ordinary glass requires less energy and has high processing efficiency; if the glass is strengthened first and then laser engraved, there is high residual stress on the glass surface, and laser processing requires higher energy, which can easily produce microcracks or chipping.

[0040] (2) Laser engraving is performed on a stress-free substrate, which helps to maintain the integrity of the structure. After subsequent strengthening, the edge of the groove formed by laser engraving is wrapped by the compressive stress layer, which makes it more crack-resistant. If strengthening is done first and then laser engraving, the compressive stress layer will be cut off during the laser engraving process, forming stress concentration points, which may weaken the strengthening effect.

[0041] (3) The surface can be cleaned and then strengthened after laser engraving, resulting in high surface flatness and cleanliness; if it is strengthened first and then laser engraved, the strengthening layer may be locally degraded due to the heat effect of the laser, affecting the surface quality.

[0042] (4) Chemical strengthening is performed after laser engraving, which does not affect the precision of laser engraving, and at the same time improves the overall impact resistance of the lens. The chemical strengthening process is an ion-level replacement that occurs in the near-surface area of ​​the glass; it does not involve the addition or deposition of materials, so it does not change the macroscopic or microscopic surface geometry, that is, the depth, width and contour of the grooves produced by laser engraving remain basically unchanged.

[0043] After chemical strengthening, the watch crystal is cleaned and dried again.

[0044] Understandably, if the watch crystal is not made of glass, but of ceramic or other materials, the chemical strengthening process can be omitted.

[0045] Step S2: Print a ring-shaped window area on the back of the watch lens opposite to the user's side, wherein the laser-engraved lines or numbers are projected onto the back side and fall completely into the ring-shaped window area.

[0046] For 2D lenses, a ring-shaped window area is typically formed directly by screen printing on the back. For 3D lenses, the ring-shaped window area is usually formed by pad printing on the back. The purpose of the ring-shaped window area is to improve the contrast of the laser-engraved logo on the user's side, making the logo clearly visible and providing good contrast when viewed from the front. The ink color of the ring-shaped window area is determined according to product requirements. The width of the ring-shaped window area is usually slightly wider than the engraved lines or numbers, ensuring that the orthogonal projection of the laser-engraved lines or numbers on the back falls entirely within the ring-shaped window area.

[0047] In this embodiment of the invention, after printing the annular window area, step S2 further includes the following sub-steps:

[0048] The back is printed with markings;

[0049] The lens with the aforementioned annular window area and markings is subjected to a heat-curing process.

[0050] Labels refer to text or graphic markings, whose core function is to convey brand, function, and compliance information, and are a key aspect of product design and manufacturing. After printing the circular window area and the label, the watch crystal is placed in an oven to bake, allowing the ink to fully cure.

[0051] Step S3: A ring-shaped ink layer is formed on the user surface using a screen printing process. The ring-shaped ink layer covers and fills the engraved lines or numbers. The thickness of the ring-shaped ink layer is greater than the depth of the engraved lines or numbers.

[0052] In this embodiment of the invention, a circular ink layer is screen-printed on the user side. The ink layer has a regular circular shape, which reduces the reliance on screen printing machine experience. The circular ink layer, in conjunction with the viewing window area, improves the contrast and aesthetics of the clock digits after the engraving. The color and width of the circular ink layer are determined according to the actual needs of the product.

[0053] In this embodiment of the invention, after forming the annular ink layer, the method further includes:

[0054] The watch lens is placed in a vacuum defoaming machine for defoaming treatment to eliminate bubble defects in the ink layer.

[0055] Debubbling treatment can eliminate bubble defects, improve the density of filling, and ensure that the ink completely and densely fills the laser-engraved structure, avoiding defects such as "hollow", "broken lines" or "uneven filling". It also ensures that the embedded marking lines are complete, the edges are clear, and the color is uniform after polishing, thus improving product consistency. In addition, debubbling treatment can also improve the interface bonding strength between the ink and the laser-engraved sidewalls and pits, thereby improving product yield.

[0056] Step S4: Remove the annular ink layer outside the engraved lines or numbers by mechanical polishing, leaving the ink filling the engraved lines or numbers to form an embedded identification structure.

[0057] In this embodiment of the invention, after preparing a ring-shaped ink layer on the user side, excess ink on the user side surface is removed by mechanical polishing, retaining the ink embedded in the laser engraving structure to form a wear-resistant, high-contrast embedded logo. The polishing medium used for mechanical polishing includes pure water, and also includes at least one of a sponge polishing pad or a carpet polishing pad.

[0058] Pure water itself is not abrasive, but it can be used as a lubricant and flotation agent. During low-speed polishing, when used with soft polishing pads such as sponges or carpets, pure water can reduce the coefficient of friction, prevent dry polishing from scratching the glass, suspend and wash away the peeled ink debris, preventing secondary scratches on the surface and avoiding the introduction of foreign impurities that could contaminate the lens or clog the grooves. Under low-speed rotation, the micropores and fiber structure of the soft polishing pads (sponges and carpets) gently rub the surface ink layer, gradually peeling it off. Because the ink in the grooves is protected by the sidewalls and is in a recessed position, the fibers of the sponge pad cannot penetrate deeply, thus its removal effect on embedded ink is extremely weak, achieving selective removal. The elasticity of the soft polishing pads can adapt to the slight curvature of the lens, ensuring uniform contact. Polishing restores the user's surface to its original smooth state, with only the laser-engraved area showing clear markings, creating an embedded visual effect.

[0059] After the above processing, the markings on the watch crystal are completely embedded beneath the watch face, resulting in a smooth, flat surface without any protrusions. During daily use, even if subjected to friction or scratches, the marking ink remains protected by the crystal structure, making it resistant to wear. Viewed from the front, the markings and the circular window create a high contrast, ensuring clear readability; the lettering on the back is also clearly visible, contributing to the overall refined and aesthetically pleasing appearance.

[0060] Example 1

[0061] In this embodiment, the watch front cover is made of 3D glass, requiring the fabrication of engraved markings. The back of the watch front cover has steps and is not a smooth surface; therefore, this solution is used to fabricate engraved markings on the user side. The specific process flow is as follows:

[0062] (1) The contour jig is fixed to the machine base by adhesive or screws. The polished watch lens blank is placed on top of the contour jig and fixed by vacuum adsorption. The customer's design drawings are converted into DXF files and imported into the laser engraving machine. The lens height and focal length are adjusted, and parameters such as scanning speed, laser frequency, and output power are set. Laser engraving is started to engrave lines on the user's face. In this embodiment, the scanning speed is 800-1500mm / s, the laser frequency is 600-1200Hz, and the output power is 5W-12W.

[0063] (2) Clean the laser-engraved product and then perform chemical strengthening.

[0064] (3) The window area and the label are pad-printed on the back, and then heat-cured. In this embodiment, the window area uses black ink, and the label is the date printed on the surface of the window ink.

[0065] (4) A circular ink layer is screen-printed on the user side. Specifically, the width of the printing area of ​​the screen is 0.05 mm larger than the viewing area, the screen mesh count is 250-300 mesh, the squeegee speed is 300-600 mm / s, and the return blade speed is 300-600 mm / s. In this embodiment, white ink is used for the circular ink layer.

[0066] (5) The product is placed in a vacuum defoamer for defoaming treatment. The defoaming temperature is 60±30℃, the defoaming pressure is 6±3kg, and the defoaming time is 7±4min.

[0067] (6) Place the product in the polishing machine, using pure water and a sponge polishing pad as the polishing medium to remove excess ink from the user surface, leaving only the ink in the engraved grooves. Ultimately, the white engraved lines and the black viewing area form a strong contrast. The polishing pressure is 100±50kg, the polishing time is 60±30min, the upper plate speed is 70±30r / min, and the lower plate speed is 7±3r / min.

[0068] The present invention has the following beneficial effects:

[0069] This invention relates to a watch lens processing method that uses laser engraving to create a groove structure, followed by screen printing an ink layer onto the user side of the watch lens. The ink fills the grooves, and excess ink is removed from the user side surface through polishing, resulting in the ink-filled logo being completely embedded beneath the lens surface. This method avoids direct exposure of the ink layer to external friction, fundamentally solving the problems of easy wear, scratches, and peeling associated with traditional surface printing, and significantly extending the lifespan of the logo. Laser engraving offers sub-micron level processing precision, enabling high-fidelity molding of extremely fine lines and complex characters with sharp edges and no burrs. Compared to screen printing / pad printing, which relies on manual machine adjustments, this method offers better graphic consistency, eliminates defects such as ink gaps and burrs, and provides a superior visual effect. Laser engraving parameters can be precisely controlled, and the screen printing and polishing processes are mature and stable. The overall process is easily automated and suitable for mass production, making it ideal for large-scale manufacturing of high-end watches.

[0070] The above are merely specific embodiments of the present invention and should not be construed as limiting the scope of the present invention. Equivalent variations made by those skilled in the art based on this invention, as well as changes well-known to those skilled in the art, should still fall within the scope of the present invention.

Claims

1. A double-sided processing method for embedding markings within a watch lens, characterized in that, The processing method includes the following steps: Step S1: Based on the design drawings, laser engrave the user face of the watch lens to form engraved lines or numerical markings; Step S2: Print a ring-shaped window area on the back of the watch lens opposite to the user's side, wherein the laser-engraved lines or numbers are projected onto the back side and fall completely into the ring-shaped window area. Step S3: A ring-shaped ink layer is formed on the user side using a screen printing process. The ring-shaped ink layer covers and fills the engraved lines or numbers. The thickness of the ring-shaped ink layer is greater than the depth of the engraved lines or numbers. Step S4: Remove the annular ink layer outside the engraved lines or numbers by mechanical polishing, leaving the ink filling the engraved lines or numbers to form an embedded identification structure.

2. The double-sided processing method for embedding markings within a watch lens according to claim 1, characterized in that, In step S1, the watch lens is an unstrengthened white glass sheet that has undergone edge grinding.

3. The double-sided processing method for embedding markings within a watch lens according to claim 2, characterized in that, Between step S1 and step S2, the following is also included: Chemical strengthening treatment is applied to watch lenses that have undergone laser engraving.

4. The double-sided processing method for embedding markings within a watch lens according to claim 1, characterized in that, In step S1, the depth of laser engraving is 0.04mm ± 0.01mm.

5. The double-sided processing method for embedding markings within a watch lens according to claim 1, characterized in that, In step S1, the laser engraving process parameters include scanning speed, laser frequency, and output power. These process parameters are set according to the target laser engraving depth, tilt angle, and graphic size.

6. The double-sided processing method for embedding markings within a watch lens according to claim 1, characterized in that, In step S2, after printing the annular viewing window area, the following sub-steps are also included: The back is printed with markings; The lens with the aforementioned annular window area and markings is subjected to a heat-curing process.

7. The double-sided processing method for embedding markings in a watch lens according to claim 1, characterized in that, In step S3, after forming the annular ink layer, the method further includes: The watch lens is placed in a vacuum defoaming machine for defoaming treatment to eliminate bubble defects in the ink layer.

8. The double-sided processing method for embedding markings within a watch lens according to claim 1, characterized in that, In step S4, the polishing medium used for mechanical polishing includes pure water, and also includes at least one of a sponge polishing pad or a carpet polishing pad.

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