A method for simulating white spots transferred by a roller heat press machine

Abstract

This invention provides a method for simulating white spot transfer using a roller heat press, comprising a flatbed heat press. By increasing the air permeability around the transfer paper in the flatbed heat press, the number of white spots after transfer is increased. Compared with the prior art, this invention, by changing the air permeability around the transfer paper, enables the transfer effect on the flatbed heat press to be close to that of a roller heat press. This allows white spots that can appear on a roller heat press but not on a flatbed heat press to be transferred using a flatbed heat press, allowing transfer paper manufacturers to adjust their processes and improve their transfer paper in a timely manner.

Description

Technical Field

[0001] This invention belongs to the field of thermal sublimation transfer printing, specifically relating to a method for transferring white dots using a simulated roller heat press machine. Background Technology

[0002] Sublimation transfer is a new process that uses an inkjet printer equipped with digital printing ink to print images such as portraits, landscapes, and text onto transfer paper in a mirror manner. The paper is then heated to about 200-220°C by a heat transfer device, causing the heat transfer ink on the paper to sublimate and penetrate into the substrate, thus realistically transferring the color image from the paper onto textiles.

[0003] With the rapid development of sublimation transfer printing technology, the white spot problem has become known as the industry's "cancer." White spots refer to the uneven coloring of the sublimated dye on the substrate during the sublimation transfer process. Some areas on the substrate lack dye, resulting in unprinted areas that appear as white spots. Defects caused by white spots during sublimation transfer are directly transferred to the substrate, affecting appearance and normal use. Printed fabric must be discarded, leading to increased overall costs and delays in delivery.

[0004] Currently, the sublimation transfer paper manufacturers and those performing sublimation transfer use different sublimation transfer equipment. Manufacturers, primarily paper companies, use heat transfer only to test the transfer quality of their own paper, thus typically using smaller flatbed heat exchangers. Manufacturers performing sublimation transfer, however, have larger production volumes and usually use large roller transfer machines. The transfer effects differ between these two types of equipment. For example, the same transfer paper might not produce white spots during testing on the manufacturer's equipment, but white spots might appear in actual production at the sublimation transfer factory. This prevents the paper manufacturer from making timely improvements and adjustments to their products. For paper manufacturers without sublimation-related business, introducing large roller transfer machines is not cost-effective. Summary of the Invention

[0005] To address the above problems, this invention provides a method for simulating white spots transferred by a roller heat press.

[0006] The object of this invention is achieved in the following manner:

[0007] A method for simulating white spots transferred by a roller heat press includes a flatbed heat press, which increases the number of white spots after transfer by increasing the air permeability around the transfer paper in the flatbed heat press.

[0008] The method for transferring white spots using a simulated roller heat press machine includes a base plate, a heating plate, and a transfer paper and a substrate placed between the heating plate and the base plate. The method for increasing the air permeability around the transfer paper is to place an air-permeable carrier on the side of the transfer paper that is not in contact with the substrate.

[0009] The method for transferring white spots using a simulated roller heat press machine, wherein the breathable carrier is a fiber pad.

[0010] The method for transferring white dots using a simulated roller heat press machine, wherein the order of placement during transfer from top to bottom is: heating plate, substrate, transfer paper, and fiber pad.

[0011] The method for transferring white dots using a simulated roller heat press machine, wherein the fiber pad has a thickness of 95-115μm and an air permeability of 2-6µm / Pa·s.

[0012] A fiber mat for increasing the air permeability around transfer paper, the fiber mat having the following formulation: 75% bleached softwood pulp with a beating degree of 60-80 and a pulping concentration of 2.5-3.0%; 6% oxidized starch, 10% light calcium carbonate, 1.5% aluminum sulfate, 2.5% binder, 2% fiber dispersant, and 3% acrylic latex.

[0013] Compared to existing technologies, this invention changes the air permeability around the transfer paper, enabling the transfer effect on a flatbed heat exchanger to approach that of a roller heat exchanger. This allows white spots that would appear on a roller heat exchanger but not on a flatbed heat exchanger to be transferred using a flatbed heat exchanger. Transfer paper manufacturers can then adjust their processes and improve the transfer paper accordingly. Attached Figure Description

[0014] Figure 1 This is a schematic diagram showing the arrangement order during the transfer process of this invention.

[0015] Figure 2 Comparison images of different transfer effects.

[0016] Figure 3 for Figure 2 Enlarged view of the white dot.

[0017] The components include: pressure handle 1, temperature controller 2, time controller 3, base plate 4, heating plate 5, rubber pad 6, fiber pad 7, transfer paper 8, and substrate 9. Detailed Implementation

[0018] 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, and 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.

[0019] In this invention, unless otherwise explicitly specified and limited, the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention.

[0020] A method for simulating white spots during sublimation transfer using a roller heat press includes a heating plate 1. By increasing the air permeability around the transfer paper in a flatbed heat press, the number of white spots after transfer is increased. Air permeability affects the transfer effect during sublimation transfer. Higher air permeability disturbs the sublimated dye, causing it to move and deviate from its original position, resulting in white spots. Large transfer manufacturers typically use roller heat presses for sublimation transfer, which have an open environment with good air permeability, making them prone to white spots. Flatbed heat presses, on the other hand, are semi-enclosed with poor air permeability, making it less likely to disturb the dye and thus less prone to white spots. Therefore, in flatbed sublimation transfer printing, increasing the permeability of the transfer paper to its surroundings can promote the movement of sublimated dyes, resulting in more white spots in the transfer and making the transfer effect of the flatbed heat exchanger closer to that of the roller heat exchanger. While the flatbed heat exchanger does indeed outperform the roller heat exchanger in terms of white spots, it is not conducive to simulating actual transfer conditions for transfer paper manufacturers. This invention essentially degrades the transfer effect of the flatbed heat exchanger, thereby meeting practical needs through this degraded effect.

[0021] The method described above simulates the transfer of white spots using a roller heat exchanger. The flatbed heat exchanger includes a base plate 4, a heating plate 5, and transfer paper and a substrate placed between the heating plate 5 and the base plate 4. The method to increase the air permeability around the transfer paper involves placing a breathable carrier on the side of the transfer paper that is not in contact with the substrate. In the original flatbed heat exchanger, the top layer is the heating plate, below the heating plate is the transfer paper, below the transfer paper is the substrate, and below the substrate is a rubber pad. The heating plate is a metal plate with poor air permeability, which prevents the dye on the transfer paper from being disturbed after sublimation, thus preventing white spots from appearing.

[0022] The method for transferring white dots using a simulated roller heat press machine, wherein the breathable carrier is a fiber pad. The raw material of the fiber pad is similar to that of paper, and existing wood pulp paper can be used as a substitute, since ordinary wood pulp paper also has a certain thickness and breathability. However, the fiber pad of this application, which can achieve a thickness of 95-115μm and a breathability of 2-6µm / Pa·s, is the most preferred.

[0023] The method for transferring white dots using a simulated roller heat press machine, as described above, involves placing the following components from top to bottom during the transfer process: heating plate, substrate, transfer paper, and fiber pad. Existing flatbed sublimation transfer machines use the same component order: heating plate, transfer paper, substrate. The advantage of this is that the heating plate directly contacts the transfer paper, resulting in good heating of the dye. However, a fiber pad needs to be added to the back of the transfer paper to increase its permeability. If added directly between the transfer paper and the heating plate, the fiber pad's good insulation would affect the sublimation of the dye. Therefore, the positions of the transfer paper and substrate were swapped. The substrate's insulation is much less than that of the fiber pad, thus having less impact on the dye. Therefore, in this invention, the component order during transfer is: heating plate, substrate, transfer paper, fiber pad, adhesive pad, and base plate. The adhesive pad is a type already found in existing flatbed heat press machines, placed on the base plate to provide support. As shown in Table 1, white dots cannot be transferred without the fiber pad. Although the heat insulation capacity of the substrate is less than that of the fiber pad, it will still affect the dye and cause a decrease in the transfer rate. This problem can be solved by increasing the transfer time. For example, in Table 1, item 15 has a temperature of 220℃ and a transfer time of 30s. The transfer is uniform and the white spots are obvious.

[0024]

[0025] To achieve the above method, a test structure for a flatbed heat exchanger that simulates white spots on roller heat exchangers is provided. The flatbed heat exchanger includes a base plate 4 and a heating plate 5. Transfer paper and a substrate are placed between the heating plate 5 and the base plate 4. An air-permeable carrier is placed on the side of the transfer paper that does not contact the substrate, thereby increasing the number of white spots after the flatbed heat exchanger transfers the material.

[0026] The experimental structure for simulating white spots on a flatbed ironing machine, as described above, uses a fiber pad as the breathable carrier.

[0027] The experimental structure of the flatbed heat exchanger that simulates the white spots of a roller heat exchanger has the following arrangement from top to bottom during the transfer process: heating plate, substrate, transfer paper, and fiber pad.

[0028] The method for transferring white dots using a simulated roller heat press machine describes a fiber pad with a thickness of 95-115 μm and an air permeability of 2-6 µm / Pa·s. Regarding the selection of thickness and air permeability, if the thickness is too thin, the air permeability is poor; if the thickness is too thick, the substrate and transfer paper experience excessive pressure, which may cause deformation or damage to the substrate or transfer paper, affecting the transfer effect. An air permeability of 2-6 µm / Pa·s provides the transfer effect closest to that of a roller heat press machine.

[0029] Regarding the fiber mats used in the aforementioned method for transferring white spots using a simulated roller heat press, which require a thickness of 95-115 μm and an air permeability of 2-6 µm / Pa·s, this invention provides a fiber mat formulation as follows: 75% bleached softwood pulp (beating degree 60-80, beating concentration: 2.5-3.0%), 6% oxidized starch, 10% light calcium carbonate, 1.5% aluminum sulfate, 2.5% binder, 2% fiber dispersant, and 3% acrylic latex. A beating enzyme of 120 g / T pulp is added during pulping. The fiber mats produced using this formulation meet the above requirements.

[0030] Figure 2 The images show a comparison of different transfer effects. The leftmost image has no white spots, while the middle and right images have white spots. Figure 3 for Figure 2 The white dot is enlarged in the image, with the white dot inside the black circle.

[0031] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several changes and improvements without departing from the overall concept of the present invention, and these should also be considered within the scope of protection of the present invention.

Claims

1. A method for simulating white dot transfer using a roller heat press, comprising a flatbed heat press, characterized in that: By increasing the air permeability around the transfer paper in a flatbed heat press, the number of white spots after the transfer is increased. The flat iron includes a base plate (4), a heating plate (5) is provided above the base plate (4), and a transfer paper and a substrate are provided between the heating plate (5) and the base plate (4). The method to increase the air permeability around the transfer paper is to provide an air permeable carrier on the side of the transfer paper that does not contact the substrate. The breathable carrier is a fiber pad; The order of placement during transfer printing from top to bottom is: heating plate (5), substrate, transfer paper, and fiber pad; The fiber pad has a thickness of 95-115 μm and an air permeability of 2-6 µm / Pa·s; The fiber mat formulation is as follows: 75% bleached softwood pulp with a beating degree of 60-80 and a pulping concentration of 2.5-3.0%; 6% oxidized starch, 10% light calcium carbonate, 1.5% aluminum sulfate, 2.5% binder, 2% fiber dispersant, and 3% acrylic latex.

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