JPS6113359Y2 - - Google Patents

Description

[Detailed explanation of the idea] (Industrial application field) The present invention relates to a base material for a transfer sheet.

(Prior Art) The transfer method has been widely used as a method for printing characters, patterns, designs, etc. on the surface of various transfer objects. The printed pattern side of the transfer sheet on which it has been formed is superimposed on the object to be transferred and heated and pressurized, and then the transfer sheet is peeled off to transfer the printed pattern to the object to be transferred. .

(Problems to be solved by the invention) By the way, the base materials for transfer sheets used in conventional transfer sheets include paper coated with thermosetting resin, and single heat-resistant films such as polyester and polyamide. However, all of these have advantages and disadvantages in terms of heat resistance dimensional stability, printing ink wettability, mold releasability, etc. In addition, as an improved product, there is a product in which paper and synthetic resin film are laminated and then a releasable matte layer containing resin, extender pigment, and release agent is formed on the film side. As time passes, the mold release agent partially precipitates on the surface, making the mold release effect uneven or unstable, resulting in changes in the suitability of the printing ink, often resulting in uneven transfer, uneven gloss, etc. There was a serious drawback to this. Furthermore, as shown in FIG. 6, conventionally, the surface condition of the base material for transfer sheets is such that the resin layer 2 coated on one side of the paper 1 has a large number of minute concavo-convex shaped portions (concave portions) with acute angles. Since the ink is shaped like a V-shaped concave portion and is not flat, not all of the ink is transferred during transfer, and a portion of the ink tends to remain in the concave portion, which ultimately causes uneven transfer.

(Means for Solving the Problems) The present invention has been devised in view of the above-mentioned problems. An object of the present invention is to provide a base material for a transfer sheet, which has a transfer surface on which the transfer material can be completely transferred onto the surface of an object to be transferred, and therefore does not cause uneven transfer, uneven gloss, etc. during transfer. shall be.

The configuration of the present invention will be explained below.

In other words, the gist of the present invention is as follows:
An extruded coating layer of polypropylene, polypropylene copolymer, or polymethylpentene resin is provided uniformly on one side of a single-sided white paper, and the surface of the extruded coating layer is coated with a cooling roll whose entire circumferential surface is matte-finished. The height of the shape is approximately 1 to 6 μm.
Formed on the pine surface with minute irregularities,
The base material for a transfer sheet is characterized in that the bottom shape of the concave portion of the concavo-convex portion constituting the mat surface is substantially flat.

Here, the white paper is one with good surface smoothness and dimensional stability, such as high-quality paper or glassine paper, and the polypropylene resin as the resin layer is mixed with an appropriate slip agent. You can leave it there. As a substitute for this polypropylene resin, polypropylene copolymer or polymethylpentene may be used.

Furthermore, the surface of the resin layer has an undulation height of about 1 to 6 μm.
The fact that the shape of the bottom of the recess that forms the m mat surface is almost flat is an essential condition for making it easy for all the ink that has entered the recess to be completely transferred during transfer. This is because if the conditions are not satisfied, ink remains in the recessed portions, resulting in uneven transfer. In addition,
As for the smoothness of the mat surface, it is more desirable that the Beck smoothness is 1000 seconds or more.

In manufacturing the base material for the transfer sheet of the present invention constructed as described above, for example, a synthetic resin such as polypropylene is typically used as the resin layer, and white paper is used as the support. As shown in FIG. 3, when a white paper 1 is passed between a cooling roll 4 and a pressure roll 5 whose entire circumferential surface is matted to a predetermined shape, one side of the paper is melt-extruded from an extrusion T-shaped die 3. It is manufactured by laminating the resin (layer) 2. Here, to give an example of the manufacturing method of the cooling roll 4 whose entire circumferential surface is matte finished, the roll surface is chrome-plated, and then iron powder or minute iron balls are bombarded onto the same surface to form minute recesses. It is obtained by providing a large number of them and then polishing them. After polishing, the depth of the recesses is about 1 to 6 μm, and in particular, the roll surface treated with iron powder has a large number of V-shapes as shown in FIG. The resin-coated surface of the transfer sheet substrate produced by this roll reflects the V-shaped recess, and is formed into a shape with a flat bottom and many pointed protrusions, as shown in Figure 1. The base material for the transfer sheet has a matte surface. Similarly, a roll made by iron balls is provided with a large number of U-shaped recesses as shown in FIG. The resin-coated surface of the transfer sheet substrate produced by this roll reflects the U-shaped recess, and as shown in Figure 2, the bottom of the recess is flat and the many protrusions are rounded. The base material for the transfer sheet has a surface having a matte surface formed in the shape. In addition, in FIGS. 4 and 5, 6 is the iron core of the roll, and 7 is the iron core of the roll.
is hard chrome plating.

Furthermore, the matte finish on the surface of the cooling roll is desirably one that requires about 1000 to 1300 seconds according to the Beck smoothness test, similar to the surface condition of the resin layer of the base material for the transfer sheet of the present invention.

(Example) Next, an example of manufacturing the base material for a transfer sheet of the present invention will be shown.

(Example) Using high-quality paper (52.3 g/m ² ) and polypropylene resin, the resin was extruded and coated onto the paper surface from an extrusion T-type die at a resin extrusion temperature of 300°C, and then the surface condition was such that the depth of the recess was 3 μm. A base material for a transfer sheet was obtained by pressing and integrating the mixture with a mat-shaped cooling roll and a pressure roll. When the Beck smoothness test was conducted on the obtained transfer sheet base material,
It had a good surface roughness of 1100 seconds.

Next, an example of optimal use of the above-mentioned base material for a transfer sheet will be shown.

Example of Use A printing ink for transfer was printed in a desired pattern using a gravure method on the matte-finished resin side of the base material for a transfer sheet produced according to the example, and the resultant was wound into a roll as a transfer sheet. Note that the printing ink is one in which a chemical that suppresses foaming is added only to a certain specific color.

Next, the transfer sheet is superimposed on a vinyl chloride sheet to which a foaming agent has been added as a transfer object, and the printed pattern on the transfer sheet is transferred by heating and pressing at a temperature below the resin foaming temperature, and then the printed pattern is transferred at a temperature above the resin foaming temperature. The surface was heated to obtain a transfer surface with a three-dimensional pattern.

(Effects) The present invention configured as described above has the following effects.

(1) Since the surface of the resin layer is semi-matte and matte, not only does the printing ink for transfer applied on it have good wettability, but also the ink remains in the minute depressions on the matte surface during transfer. Since the image is completely transferred without any scratches, the transfer surface of the transfer sheet appears as it is on the surface of the object to be transferred, and uneven gloss and uneven printing do not occur.

(2) Since the resin layer of the base material for the transfer sheet uses a heat-resistant polypropylene resin, the transfer sheet manufactured using this base material will not shrink due to heat when transferring to an object. Since no release agent is added, the transfer surface can be accurately transferred to the object to be transferred, and since no release agent is added, there is no change in the release effect over time.

(3) Since the base material for the transfer sheet of the present invention uses white high-quality paper as the base sheet, even when an ink composition for a printed pattern is applied to the resin surface of the transfer sheet, the color of the ink can be very accurately obtained. It is easy and accurate to determine the color toning.

(4) As shown in Figure 6, the base material for transfer sheets obtained by the conventional pine roll has an acute-angled concave shape, resulting in ink residue; compared to this, the base material for transfer sheets of the present invention As the resin surface is matte finished, the ink composition applied to the resin surface is completely transferred to the object during transfer without any part of it remaining in the minute recesses caused by the matte finish. There is an advantage that the used transfer sheet base material can be reused for packaging materials, etc.

[Brief explanation of the drawing]

Figures 1 and 2 are partially enlarged sectional views of the base material for transfer sheets of the present invention, and Figures 4 and 5 are cooling used for manufacturing the base material for transfer sheets of the present invention shown in Figures 1 and 2. Partially enlarged sectional view of roll, 3rd
The figure is a schematic diagram of the process for manufacturing the base material for a transfer sheet of the present invention, and FIG. 6 is a partially enlarged sectional view of a conventional base material for a transfer sheet. 1... White paper, 2... Resin (layer), 3... Extrusion T-type die, 4... Cooling roll, 5... Pressure roll, 6... Iron core, 7... Hard chrome plating.

Claims (1)

[Scope of utility model registration request] An extruded coating layer of polypropylene, polypropylene copolymer, or polymethylpentene resin is provided on the entire surface of one side of white paper, and the surface of the extruded coating layer is heated to a raised height of about 1 by a cooling roll whose entire circumference is matte finished. A base material for a transfer sheet, which is formed on a mat surface having minute irregularities of ~6 μm, and is characterized in that the bottom shape of the concave portion of the concavo-convex portion constituting the mat surface is substantially flat.