JPH0617132B2 - Shrink label - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a shrinkable label made of a heat shrinkable plastic film, and more particularly to a label that can be beautifully put on a cryogenic container.

(Prior Art) As a shrinkable label for covering a container such as a bottle or a can, a heat-shrinkable film made of polyvinyl chloride, polystyrene, polypropylene or the like formed in a tubular shape is used.

A method of blowing hot air is often used as a means for shrinking the label. (Problems to be solved by the invention) However, some containers are filled with low-temperature contents, in which case the label does not shrink evenly and wrinkles or avatar-shaped unshrinkage occurs. There is a problem that the department is overhanging.

As a countermeasure, the label may be shrunk by hot water or steam, but it is not practical because it has defects such as whitening of the film and rusting of the container.

Further, if the label is put on after warming the container, a good finish can be obtained, but it is inefficient and some contents dislike heating.

(Means for Solving Problems) The present invention provides a shrinkable label that solves the above-mentioned problems of the related art and can perform beautiful labeling with hot air even in a low temperature container.

That is, in the present invention, a surface of a heat-shrinkable plastic film having a smooth surface and a transparent surface is printed, and a surface roughness (10
A shrinkable label formed by providing a rough surface layer having a point average roughness of 1.5 to 6 μm, and forming the rough surface layer inwardly in a cylindrical shape, and the unevenness of the inner surface of the label improves sliding with the container. It eliminates wrinkles and avatars.

The present invention will be described in detail below.

FIG. 1 is a perspective view of an example of the label of the present invention.
Is a heat-shrinkable plastic film, 2 is a rough surface layer, and 3 is a printed layer formed on the surface of the film 1.

The heat-shrinkable plastic film 1 which is the main component of the label of the present invention has a thickness of usually about 40 to 80 μm, and a conventional transparent film such as polyvinyl chloride, polystyrene, polypropylene or the like can be used as it is.

This film mainly shrinks in the circumferential direction when formed into a tubular shape, and for example, a film that shrinks by 20 to 60% at 100 ° C. is used.

Further, it may have a slight shrinkage of about 10% or less in the axial direction when formed into a tubular shape.

It is necessary to print the label, and it is preferable to print the label on the back side as shown in FIG.

However, when the surface of the rough surface layer 2 or the film 1 itself is roughened and printing is performed on the rough surface layer 2, the printed appearance is poor and the rough surface is filled and smoothed to obtain desired performance. Absent.

Therefore, a transparent film having a smooth surface (normal film) is used as the film 1, and one surface (back surface) thereof is subjected to printing 3 and then the rough surface layer 2 is formed thereon.

The easiest way to form the rough surface layer 2 is to apply a coating agent in which fine particles are mixed with an appropriate binder to the printing surface of the film 1.

As another method, a film having a heat shrinkability similar to that of the film 1 and having a roughened surface by adding fine particles can be attached to the printing surface of the film 1.

The surface roughness of the rough surface layer is 10-point average roughness Rz (JIS
In B0601), the range is 1.5 to 6 μm.

If it is smaller than this, wrinkles or avatars are generated when the container is shrink-coated, and if it is larger than this, unevenness may appear on the label surface when it is covered on the container, depending on the thickness of the film 1. Not preferable.

In order to obtain such a surface roughness, the particle size and amount of the particles to be added may be properly adjusted.
Particles having a size of 10 μm may be added to the binder in an amount of about 2 to 10% by weight.

Here, the average particle size is mainly related to the height of the protrusions formed,
The added amount mainly contributes to the number of protrusions.

When the amount added is in the above range, the number of protrusions is about 5 to 20 per 1 mm in cross section, which is suitable.

Types of particles to be added include silica, magnesium oxide, calcium carbonate and the like.

The rough surface layer may have an extremely thin thickness such that particles do not fall off, and is, for example, about 2 to 10 μm.

The label of the present invention is obtained by forming the laminated film obtained as described above into a cylindrical shape so that the rough surface layer is inside.

The label of the present invention is particularly suitable for a container having a low temperature of room temperature or lower, particularly 5 ° C. or lower, such as canned mandarin orange or pineapple, and can be beautifully covered without causing wrinkle avatar.

Further, in addition to the cryogenic container, the effect is great even when used in a container having poor slipperiness, a container having a large-diameter portion and a small-diameter portion and usually easily wrinkled,

(Example) To 100 parts by weight of polyvinyl chloride resin having an average degree of polymerization of 800, 3 parts of an organotin stabilizer, 10 parts by weight of a plasticizer DOP and 15 parts by weight of an MBS resin were added, and a sheet having a thickness of 100 μm was formed by extrusion molding. This was stretched 2.5 times in the transverse direction to obtain a film having a smooth surface with a thickness of 40 μm, a heat shrinkage rate (100 ° C.) in the transverse direction of 55% and a haze of 2%.

Then, a pattern was printed on one side of the obtained film by gravure printing, and a transparent medium mainly composed of vinyl chloride-vinyl acetate copolymer resin was added with 3% by weight of amorphous silica fine particles (trade name: Cyloid) on the coated film. The agent was applied to a thickness of 4 μm to form a rough surface layer.

Table 1 shows the names of the particles used, their average particle diameters, and the surface roughness Rz of the obtained rough surface layer.

Rz was measured with a Talysurf IV type surface roughness meter manufactured by Taylor Hobson Co., Ltd., using a diamond needle having a tip curvature of 2.5 μm, and a needle pressure of 0.1 g.

The film thus obtained was formed into a tube with the rough surface layer on the inside to form a label, and the label was placed on a can at a temperature of 5 ° C. Then, this was shrink-coated with a shrink tunnel at the hot air temperature and heating time shown in Table 2, and the finished appearance was observed. The results are also shown in Table 2.

The finished appearance was evaluated as ◯ when there were no wrinkles and avatars, Δ when there were some wrinkles and avatars remained, and as × when wrinkles and avatars were extremely unusable.

From the above results, when the surface roughness is 1.5 μm or more, the shrink finish appearance is good, but the surface roughness is too large N
With o5, unevenness appeared on the label surface, which was not preferable.

(Effect of the invention) The label of the present invention has improved slipperiness with the container due to moderate irregularities on the inner surface, and when the label is partially covered with a low temperature container, the label partially contacts the container and remains as an uncontracted portion even when the temperature is lowered. And a good finished appearance can be obtained.

Further, since the rough surface layer is provided on the print, the rough surface layer does not affect the print appearance at all, and the same beautiful printing as the conventional label can be performed.

[Brief description of drawings]

 FIG. 1 is a perspective view of an example of the label of the present invention. 1 ... Heat-shrinkable plastic film 2 ... Rough surface layer, 3 ... Printing layer

Claims (1)

[Claims] 1. A surface of a heat-shrinkable plastic film having a smooth and transparent surface is printed, and a rough surface layer having a surface roughness (10-point average roughness) of 1.5 to 6 μm is provided on the surface. A shrinkable label that is formed into a cylindrical shape with the layers inside.