High-definition acrylic character goods

Abstract

We provide acrylic character goods that can achieve high-definition image expression and improved print quality even when ink adhesion, image quality, color degradation due to light transmission, and the effects of reflection and transmission when printing on the back side are a problem. [Solution] Acrylic character goods 360 are provided with a first PET film 110 on which a character image is formed by UV offset printing or on-demand printing, a second PET film 130 on which a white-plate image is formed by UV inkjet printing, and an image sheet in which the first PET film and the second PET film are bonded together via an adhesive or UV-curing adhesive, thereby achieving high-definition image expression and improved print quality.

Description

[Technical Field]

[0001] This invention relates to acrylic character goods made using high-definition printing and manufacturing techniques. [Background technology]

[0002] Previously, direct printing on acrylic plates had limitations in ink adhesion and image quality, making it difficult to achieve clear print quality. Furthermore, when attempting to use PET film as a printing material, it was difficult to handle small-lot production, and there were also issues with air bubbles, lifting, and misalignment due to shrinkage during lamination and processing.

[0003] To solve these problems, there was a need for higher-resolution printing, improved alignment accuracy, and the prevention of air bubbles and lifting during lamination. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-69577 Summary of the Invention [Problem to be solved by the invention]

[0005] With conventional direct printing on acrylic plates, it has been difficult to achieve high-resolution image expression and improve print quality due to issues such as ink adhesion, image quality, color degradation due to light transmission, and the effects of reflection and transmission when printing on the back side.

[0006] In addition, misalignment due to thermal shrinkage during lamination and raised lines, bubbles, and distortions caused by unevenness on the printed surface were prone to occur, and there were also issues such as increased production time and costs due to an increased proofreading process and the inability to produce small lots. [Means for solving the problem]

[0007] This device is configured to include a first PET film on which a character image is formed by UV offset printing or on-demand printing, a second PET film on which a white-printed image is formed by UV inkjet printing, and an image sheet in which the first PET film and the second PET film are bonded together using a pressure-sensitive adhesive or UV-curable adhesive. Furthermore, the thermal shrinkage characteristics of the first PET film and the second PET film are predicted, and the image sheet is aligned. This fundamentally solves the problems associated with conventional direct printing, such as image quality degradation, misalignment, and color shifts. Here, as described above, the customer may be able to choose between two types of printing, high-quality UV offset printing and on-demand printing, which is low cost, allows small lot production, and allows for time-saving production, based on the balance between quality and cost. In addition, adhesives are applied to the PET film before printing. Compared to UV-curing adhesives, adhesives require fewer steps, are easier to handle, and are less expensive, but they have disadvantages such as stickiness due to glue spilling out from the cut surface, and their adhesive strength and aesthetics are inferior to UV-curing adhesives. It may be acceptable to allow the customer to choose whether to use adhesive or glue for lamination.

[0008] By bonding the image sheet to a transparent acrylic plate using pressure sensitive adhesive or UV curing adhesive, and suppressing the occurrence of unevenness, air bubbles, and lifting on the printed surface, it is possible to create high-quality acrylic character goods that ensure aesthetics, transparency, and adhesive strength. [Effects of the Invention]

[0009] According to this invention, high-resolution printing using PET film and precise alignment taking into account thermal shrinkage characteristics can consistently achieve clear image expression and high print quality, which was difficult with conventional direct printing on acrylic plates.

[0010] Furthermore, the pressure-sensitive adhesive or UV-curing adhesive prevents the ink layer from lifting or creating bubbles due to unevenness between the image sheet and the transparent acrylic plate, and the bonding structure using the UV-curing adhesive prevents bubbles and lifting, making it possible to manufacture high-quality acrylic character goods with excellent aesthetics, transparency, and adhesive strength at low cost, with short delivery times, and in small batches. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a structural diagram of a second PET film (white version). [Figure 2] FIG. 1 is a structural diagram of the first PET film (character image). [Figure 3] FIG. 1 is a cross-sectional structural view of a PET sheet in which a first PET film sheet and a second PET film sheet are bonded to an acrylic plate to form an integrated PET sheet. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. Figures 1 and 2 are structural diagrams showing the components of an acrylic character goods product as viewed from the side.

[0013] As shown in Figure 2, the first PET film 110 is a base material for forming character images, and is a polyethylene terephthalate (PET) film with strictly controlled thickness and heat shrinkage characteristics. This film has high surface smoothness and excellent dimensional stability, making it possible to print fine details. On-demand printing is also possible.

[0014] The character image is the main design element formed on the first PET film 110. The character image is printed in high-resolution, multicolor using a UV offset printing device (not shown), allowing for fine gradation and color expression. During printing, the surface treatment and ink composition are optimized to ensure that the ink 121 shown in Figure 2 adheres evenly to the surface of the PET film.

[0015] The UV offset printing device (not shown) is responsible for transferring a character image in high resolution onto the first PET film 110. The offset printing method has a mechanism for transferring ink from a plate cylinder via a blanket cylinder, and the ultraviolet-curable component in the ink is instantly cured by a UV lamp that is irradiated while the ink is being transported, preventing bleeding and smearing of fine lines and fine patterns and forming sharp edges.

[0016] As shown in Figure 1, the second PET film 130 is a base material for forming a white image, and is also made of a PET material with high dimensional stability and printability. The second PET film 130 serves as a base for improving the color development and visibility of the character image.

[0017] The white image is an opaque white layer made of ink (white) 141 formed on the second PET film 130, and is responsible for supporting the color development of the character image and preventing the background from showing through. The ink is layered in dots with high precision and density using a UV inkjet printing device (not shown), reducing the effects of transmitted light and preventing color variations due to the base color.

[0018] The UV inkjet printing device (not shown) is a specialized device for creating white prints, equipped with a printhead that precisely controls and ejects minute ink droplets. During printing, the UV-curable component in the ink is instantly cured by ultraviolet light, preventing dots from spreading or bleeding, resulting in a uniform, highly opaque white print layer.

[0019] Although the first PET film 110 and the second PET film 130 undergo different printing processes, an important characteristic they share is their thermal shrinkage behavior. Both films undergo minute dimensional changes (thermal shrinkage) due to the thermal history generated during the printing process and subsequent processes, so this is corrected in advance through a thermal shrinkage characteristic correction process.

[0020] In the thermal shrinkage characteristic correction process, the amount of dimensional change during heating and cooling is measured according to the material and thickness of the first PET film 110 and the second PET film 130, the type and thickness of the printing ink layer, etc., and the image data is enlarged or reduced and the registration mark position is redesigned. This allows the character image and white plate image to be precisely overlapped when finally laminated together.

[0021] The printing process step is a process that includes various printing processes on the first PET film 110 and the second PET film 130 described above, and the conditions of each printing device (ink viscosity, UV irradiation amount, transport speed, etc.) are optimized. This maximizes ink adhesion and image resolution.

[0022] After the character image and white image are printed, the alignment process step begins. In this process, an alignment device (not shown) is used. The alignment device (not shown) uses an optical sensor or camera to read and calculate the positions of the reference marks and register marks on both films, achieving position correction on the order of microns.

[0023] The alignment device also has an automatic fine-tuning mechanism that corrects distortion and shrinkage of both films in real time to ensure that the character image and the white plate image are perfectly aligned, eliminating even minute misalignments that are difficult to see with the naked eye.

[0024] Once the alignment step is complete, the lamination step begins. Here, a UV-curable adhesive is applied between the two films, and then the films are laminated together using a pressure-bonding device. Note that in this invention, a pressure-sensitive adhesive may be used instead of a UV-curable adhesive.

[0025] The UV-curable adhesive is essential for ensuring the reliability of bonding and aesthetic appearance of this invention, and is primarily composed of a mixture of monomers and oligomers that can be adjusted to a low to medium viscosity. It has the optimal viscosity and fluidity to adequately fill in the minute irregularities and grooves caused by the ink layer while suppressing air bubbles and lifting.

[0026] The pressure bonding device is a mechanism for applying a predetermined uniform surface pressure during bonding, and uses rollers and press plates to spread an extremely thin and even adhesive layer between the two films. The pressure and speed are automatically controlled, and local lifting caused by convex parts of the ink layer is effectively suppressed.

[0027] The first PET film 110 and the second PET film 130 are integrated by the lamination process step, and this is formed as an image sheet. The image sheet has the character image and the white image superimposed with high precision, and is an intermediate body that will be laminated to the acrylic plate in a subsequent process.

[0028] The thickness of the ink layer and adhesive layer on the image sheet is precisely controlled, and the sheet may be smoothed to improve its appearance and transparency. This minimizes the risk of air bubbles forming and poor adhesion to the acrylic plate in subsequent processes.

[0029] In the acrylic plate lamination process step, the image sheet is laminated to a transparent acrylic plate 190 using a UV-curable adhesive. The acrylic plate 190 is a transparent acrylic resin whose thickness and optical properties are strictly specified, and it has high visible light transmittance and high surface smoothness.

[0030] The surface of the transparent acrylic plate 190 has been anti-static treated and degreased and cleaned in advance, and the wettability of the adhesive has been optimized to improve adhesion and reduce the risk of air bubbles or spillage.

[0031] When the image sheet is attached to the acrylic plate 190, a pressure bonding device is used again to apply uniform pressure to the entire surface, eliminating unevenness in the adhesive layer and residual air bubbles. After bonding, a powerful UV lamp is used to irradiate the adhesive, which completely hardens in a short time.

[0032] The laminated body is a composite structure in which the transparent acrylic plate 190 and the image sheet are integrated, and is highly durable against external impacts and abrasion. The internal ink and adhesive layers are designed to minimize the occurrence of unevenness and air bubbles on the surface.

[0033] The bubble suppression structure is used to optimize the flow and degassing behavior of UV-curable adhesives, and by adjusting the coating thickness, flow path design, and compression conditions, it efficiently expels fine air from the adhesive interface, minimizing residual air bubbles.

[0034] The lift-up prevention structure is a design element to prevent local lift-up caused by ink protrusions on the image sheet or uneven adhesive application. For example, specific measures include adjusting the viscosity and surface tension of the adhesive, controlling the surface pressure of the pressure-bonding device, and optimizing the surface roughness of the acrylic plate 190.

[0035] After the above bonded body is formed, the bonded body is cut into a desired shape in a cutting process step. The cutting device is mainly composed of a laser processing machine or a router processing machine, and is designed to be able to cut the acrylic plate 190 and the image sheet with high precision and without burrs.

[0036] The cutting equipment is equipped with an automatic control function based on CAD data, and can handle complex curves and detailed shapes. During cutting, cooling air and optimal laser output control are used to minimize the thermal impact on the material and prevent the cut surface from becoming cloudy or discolored.

[0037] Once the cutting process is complete, the laminated body takes on the final product form as a finished acrylic character merchandise 360. The finished product achieves a high level of balance between the high definition of the character image, the transparency of the acrylic plate 190, and the aesthetic appearance of the adhesive interface.

[0038] The process flow of the manufacturing system is clearly shown to proceed in the following order: printing process, heat shrinkage characteristic correction process, alignment process, lamination process, acrylic sheet lamination process, and cutting process. The flow of information and materials between each process and the coordination between each device are also systematically managed.

[0039] In the printing process, a UV offset printing device and a UV inkjet printing device are operated in parallel or sequentially to form images on each PET film. The formed first and second PET films are managed based on the data corrected and designed in the thermal shrinkage characteristic correction process.

[0040] In the thermal shrinkage characteristic correction process, the print image data is corrected based on the thermal shrinkage data obtained from various test pieces and preliminary evaluations, and dimensional deviations at the actual processing site are prevented in advance. This fundamentally reduces image and white plate deviations in the final product.

[0041] In the alignment process step, an alignment device with an image processing algorithm and high-precision drive control is used to detect multiple reference marks and perform fine position adjustments in real time using servo motors and linear actuators.

[0042] The UV-curing adhesive in the lamination process is applied using a metered-volume dispenser or slit coater. The thickness of the applied adhesive is precisely set within the range of several microns to several tens of microns depending on the ink layer irregularities and the final transparency.

[0043] The bonding conditions used by the bonding device are optimized based on the bonding area, adhesive viscosity, and film thickness, and the press pressure and bonding time are automatically controlled. Vacuum bonding and heat bonding are also applied as necessary to prevent defects caused by residual air or uneven bonding.

[0044] After the image sheet is formed, in the acrylic plate lamination process step, the surface of the transparent acrylic plate 190 is degassed and anti-static treated in advance, making it less likely for dust to adhere and for adhesive defects to occur. When laminating the image sheet, a pressure bonding device applies uniform surface pressure to the entire surface.

[0045] The UV-curable adhesive of this invention has an optimized molecular structure design and additive blend to maximize adhesion to the acrylic resin, PET film, and ink layer. After UV irradiation, the photoinitiator causes a rapid polymerization reaction, resulting in complete curing in a short time and significantly reducing interface lifting and bubble formation.

[0046] The inside of the laminated body has a combined function of an air bubble suppression structure and a lift-up suppression structure. For example, if the adhesive has too high a fluidity, air tends to remain in uneven areas, so by optimally designing the viscosity and controlling the compression speed, a path is created that makes it easy for air bubbles to be expelled from the interface.

[0047] The anti-floating structure allows the ink layer and areas around the registration marks that have locally increased thickness to adhere to the acrylic plate 190, maintaining the transparency and smoothness of the final acrylic character goods 360.

[0048] In the cutting process, the CNC control of the cutting equipment allows for high-precision processing of complex shapes and narrow-edged shapes. In the case of laser cutting, parameters may be set to minimize the heat-affected zone, and a post-cutting edge chamfering process may be added.

[0049] The cutting device's processing head has been designed with an appropriate depth of focus and output profile to cut the image sheet in one go, including the ink and adhesive layers, ensuring smooth cut surfaces with a high-quality appearance.

[0050] The completed acrylic character goods product 360 has a high-definition reproduction of the character image, and the sense of depth and color development are remarkable, taking advantage of the transparency of the acrylic plate 190. In addition, the white image effectively prevents the background from showing through and color deterioration.

[0051] In one example of the present invention, the thickness of the first PET film 110 and the second PET film 130 is 5 μm, and the thickness of the acrylic plate 190 is 3 mm, resulting in a lightweight, sturdy structure that is resistant to image distortion and deformation. Note that the above thicknesses may vary depending on the product use and customer requests.

[0052] The amount and viscosity of the UV-curing adhesive applied are optimized according to the maximum thickness of the ink layer on the image sheet and the surface roughness of the acrylic plate 190, and are precisely controlled to prevent the adhesive from spilling out or swelling.

[0053] When forming the laminate, controlling the working environment (temperature and humidity) is also important. In particular, the curing reaction of UV-curable adhesives is sensitive to ambient temperature and UV irradiation intensity, so the environment is monitored and automatically adjusted throughout the entire production line.

[0054] In the manufacturing process of image sheets and laminates, intermediate inspections such as appearance inspection, dimensional inspection, and bonding strength test are carried out at any time. This allows defects to be detected early in the process, improving yield.

[0055] In the present invention, image correction using a thermal shrinkage characteristic correction process is essential at the design stage of the print image data, and the correction value that takes into account the difference in thermal shrinkage between the two films is reflected in the CAD data, thereby eliminating image misalignment in the final acrylic character goods product 360.

[0056] The automated control of the entire manufacturing system is achieved by exchanging process progress and status signals between each device, and feedback control of the crimping and cutting devices in particular contributes to stabilizing production quality.

[0057] The laminate of the present invention is not simply a multilayer laminate, but a functional composite material in which interface design, material properties, and process control are comprehensively optimized. In particular, the introduction of a bubble-suppressing structure and a lift-up suppressing structure has resulted in higher appearance quality and reliability than conventional products.

[0058] Finished acrylic character goods 360 are individually wrapped and have a surface protection film applied in the final process, and additional processing may also be used to prevent scratches and dirt during shipping and to maintain their appearance.

[0059] The present invention, with the above-mentioned configuration, enables small-lot, high-mix production and short delivery times, and realizes an integrated automated manufacturing process from design to finished product. Furthermore, the parameters of each process are designed to be flexibly changeable according to product specifications.

[0060] As described above, the acrylic character goods manufacturing system of the present invention realizes the production of high-definition, high-transparency, and high-reliability character goods, which was previously difficult to achieve, through the coordinated operation of each component and optimized material and process management. [Explanation of symbols]

[0061] 110 First PET film 130 Second PET film 190 Acrylic Plate 360 Acrylic character goods completed product

Claims

1. a first PET film on which a character image is formed by UV offset printing or on-demand printing; a second PET film on which a white image is formed by UV inkjet printing; an image sheet in which the first PET film and the second PET film are bonded together via a pressure-sensitive adhesive or a UV-curable adhesive; Acrylic character goods with

2. The first PET film and the second PET film are The thermal shrinkage characteristics are predicted and the image sheet is aligned. The acrylic character goods according to claim 1.

3. The image sheet is a laminated body that is bonded to a transparent acrylic plate via a pressure-sensitive adhesive or a UV-curable adhesive, The bonded body is cut into an arbitrary shape. The acrylic character goods according to claim 1 or 2.

4. The pressure-sensitive adhesive or UV-curable adhesive is The ink layer is prevented from floating or generating bubbles between the image sheet and the transparent acrylic plate due to unevenness. The acrylic character goods according to claim 3.

Images