JPH02132487A - Label - Google Patents

Abstract

PURPOSE:To prevent the generation of the air pools between a hollow product and a label by roughening the surface of an adhesive layer by the roughness of the surface of a paper-like layer joining the adhesive agent of the label so that the easy dissipation of the air from the surface is allowed by the presence of the spacing formed between a parison and the adhesive layer at the time when the adhesive layer is melted by the heat of a parison at the time of blow molding. CONSTITUTION:The label is constituted of a multilayered composite film 2. The composite film 2 is formed by laminating the paper-like layer B consisting of a unaxially stretched film of a resin compsn. contg. fine inorg. powder at 35 to 65wt.% ratio and 65 to 35wt.% propylene resin on one surface of the base material layer A consisting of a biaxially stretched film contg. 5 to 30wt.% inorg. resin powder and 95 to 70wt.% propylene resin. The paper-like layer D consisting of a uniaxial film of a resin compsn. contg. 25 to 65wt.% fine inorg. powder having 2,000 to 12,000cm<2>/g specific surface area and 1.8 to 8mum average grain size and 85 to 35wt.% propylene resin is formed on the layer A on the side opposite to the layer B.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to hollow body products, especially shampoo containers, cooking oil, motor oil containers, toilet disinfectant containers, painted rice transplanter floats, toys, surfing boards, etc. It relates to labels (including blanks) that can be pasted.

[Conventional technology] Conventionally, in order to manufacture resin molded containers with labels,
The painted container is molded into one piece by inserting a blank or label into a mold in advance and then molding the container using various molding methods such as injection molding, blow molding, differential pressure molding, and foam molding. Ta.

Labels (including blanks) used in such molding methods are generally gravure printed resin films, offset multicolor printed synthetic papers (for example, Japanese Patent Publication No. 46-40794, Japanese Patent Publication No. 54-31030).
(Japanese Patent Publication No. 1,090,059, etc.), or an aluminum label in which polyethylene is laminated on the back side of aluminum foil and gravure printing is performed on the surface of the foil.

However, in the manufacturing method of resin molded containers decorated with labels as described above, high pressure f100 such as injection molding is required.
The method of fusing the label and the molten resin container at a pressure of ~1000 kg/cm2) yields a product with a good appearance; however,
Differential pressure molding (2-7 kg/cm2). Hollow molding fl~
lOkg/cm2). Vacuum forming (100~-65
In methods of molding at low pressures such as 0 mmHgl, there is insufficient air escape between the label and the melting container.
There is a problem in that blisters are generated here and there between the container and the label, which significantly impairs the appearance of the container.

In order to improve blistering during blow molding and differential pressure molding, and to enable multicolor printing of labels, a method has been proposed in which synthetic paper made of a multilayer structure of stretched films is used as labels (Japanese Patent Laid-Open Publication No. 5869015). has been done.

In this method, a uniaxially stretched polypropylene film containing 8 to 65% by weight of inorganic fine powder is provided as a paper-like layer on one side of a biaxially stretched polypropylene film base layer, and a paper-like layer is provided on the opposite side of the paper-like layer. The wall thickness is 1 to 10 μm on the surface.
A label made of a multilayer composite film with a wall thickness of 30 to 300 μm formed by providing a polyethylene film as an adhesive layer is fixed so that the paper layer side of the label is in contact with a mold, and then the adhesive layer side of the label is fixed so that the paper layer side of the label is in contact with a mold. Apply molten polyethylene under pressure or reduced pressure, then
Containers are manufactured by cooling this polyethylene and attaching labels.

In this method of attaching a label, a propylene resin having a melting point higher than that of the polyethylene container to be molded is used as the material resin for the label, so even though the base material layer of the label is a stretched film, When the polyethylene of the adhesive layer is thick, heat during molding is not transmitted to the base material layer, which has the advantage that wrinkles are less likely to occur due to shrinkage.

[Problem to be solved by the invention] However, in order to improve the surface gloss of the hollow container,
The inner surface of hollow molds is plated or mirror finished, and when such molds are used,
Even if the label described in JP-A-58-69015 is used, blistering occurs on the label of the blow-molded container at a rate of about 0.6% of the product.

[Means for Solving the Problems] The present inventors believe that the above-mentioned fact is due to the improvement in the smoothness of the inner surface of the mold, which causes air pockets that are delayed to escape between the parison and the label. As a result of intensive research in order to solve the above problem, we found that the roughness of the surface of the adhesive layer of the label was determined by Japanese Patent Laid-Open No. 5
The surface is rougher than that of the adhesive layer (back layer) of the label in Publication No. 8-69015, making it easier for air to dissipate from the surface of the adhesive layer and eliminating the formation of air pockets between the hollow product and the label, resulting in a smooth surface. It was possible to obtain a label that was free from blistering even when used with a mold that was highly sensitive.

That is, the present invention provides a label composed of a multilayer resin film, in which the multilayer resin film contains 5 to 30% by weight of inorganic fine powder and 95 to 70% by weight of propylene resin.
A resin composition containing 35 to 65% by weight of an inorganic fine powder and 65 to 35% by weight of a propylene resin on one side of a biaxially stretched film base layer fA) of a resin composition containing 35 to 65% by weight of a propylene resin. A paper-like layer made of a uniaxially stretched film (
B) is laminated, and on one side of the base material layer (A) opposite to this paper-like layer (B), a material having a specific surface area of 2.000 to 12.0
00cm27g and the average particle size is 1.8-8
A paper-like layer (D) consisting of a uniaxially stretched film of a resin composition containing 20 to 65% by weight of micron inorganic fine powder and 80 to 35% by weight of a propylene resin; D) has a wall thickness of 1 to 10 μm made of a uniaxially stretched film of an ethylene resin with a melting point of 80 to 130°C on the outer surface.
A laminate consisting of at least four layers, with an adhesive layer (E) of The label is characterized in that (Ra) is 0.5 to 5 μm.

[Specific Description of the Invention] Hereinafter, the label of the present invention will be specifically explained using the drawings.

FIG. 1 is a sectional view of a label 1 of the present invention. In the figure, A is a base material layer made of a biaxially stretched film, B, C, and D are paper-like layers made of a uniaxially stretched film, E is an adhesive layer, and the multilayer composite film 2 contains film layers A to E. . 3 is the printing done on the paper-like layer B.

Each of the layers A to D constituting the multilayer composite film 2 may be a single layer or a multilayer, and in FIG.
Paper-like layer B. where paper-like layer B has a different composition. An example consisting of two layers, B2 and B2, is illustrated.

The multilayer composite film 2 is prepared by heating the resin composition forming layer A in advance at a temperature lower than the melting point of the propylene resin, for example, 3.5 to 158 degrees Celsius, using the difference in circumferential speed between the roll groups.
A molten film of the resin composition forming layer B is laminated on one side of the film obtained by longitudinal stretching to ~7 times, and
After laminating a molten film of the resin composition forming the optional layer C on the other side of the layer as necessary, the resin compositions forming the D layer and the E layer are separately extruded. After kneading using a machine, it is fed into one die, laminated in a tie, and when coextruded, the E layer of the molten sheet is laminated on the C layer so that it is on the outside, and then the adhesive layer is E is melted, but each paper-like layer B. containing a propylene resin is melted. It is manufactured by horizontally stretching C and D and the base material layer A at a temperature at which they do not melt (a temperature below the melting point of the propylene resin).

By stretching, in the base layer A and the paper-like layers B-C, a large number of micropoids (vacancies) are generated with the inorganic powder contained in the layers as cores, making the layers opaque and decreasing the density. As a result, the weight of the multilayer composite film 2 is reduced. In addition, cracks are generated on the surface of the paper-like layer B with the inorganic fine powder as the nucleus, and the adhesion and drying properties of the printing ink are improved. However, when the paper-like layer B becomes a biaxially stretched oriented film, there are many chances for the inorganic fine powder to fall off, and deep cracks caused by axial stretching may disappear due to further stretching. This results in offset printability inferior to that of a uniaxially stretched oriented film. Therefore, the surface of the paper-like layer B is preferably a uniaxially stretched oriented film.

Another method for producing the multilayer composite stretched film 2 is to form a paper-like layer B having the same composition on both sides of a longitudinally stretched film made of a resin for the base layer A. A molten film of resin for C is laminated, and a molten film for paper layer D is further laminated only on one paper layer C, or a paper layer is laminated on one side of a longitudinally stretched film of resin for base layer A. A molten film of resin for B is laminated, a molten film for paper-like layer D is laminated on the other side, and then,
A molten film for the adhesive layer E is laminated on this paper-like layer D, and this laminated film is laterally stretched at a temperature higher than the melting point of high-density polyethylene and lower than the melting point of the propylene resin. It's okay.

The propylene-based resin used in the paper-like layer is a propylene homopolymer, or a propylene-based resin containing propylene as a main component, and an α-based resin such as ethylene, butene-1, hexene-1, pentene-1, propylene, or 4-methylpene-1. There are random or block copolymers with one or more selected from polyolefins, and those with a crystallinity of 40% or more, preferably 70% or more, more preferably 94% or more are particularly suitable. It is.

Further, the inorganic fine powder for the A layer, B layer and C layer has a particle size of 15 μm or less, preferably 0.05 to 5 μm.
talc, diatom, heavy calcium carbonate, calcined clay,
Titanium oxide, barium sulfate, Myriki, etc. are used.

The inorganic fine powder for layer D has a specific surface area of 2,000
Heavy calcium carbonate or the like having a particle size of 0 to 12.0 Ocm2/g and an average particle size of 1.8 to 8 μm is used.

A portion (10% by weight or less) of the propylene resin can be mixed with high density polyethylene, low density polyethylene, linear polyethylene, ethylene/vinyl acetate copolymer, ethylene/acrylic acid copolymer, ethylene/acrylic acid alkyl ester, etc. Polymer (alkyl group has 1 to 8 carbon atoms), ethylene/methacrylic acid alkyl ester copolymer (alkyl group has 1 to 8 carbon atoms), metal salt of ethylene/methacrylic acid copolymer (Zn. Al. Li. K. Na)
It may be replaced with ethylene resin such as or polystyrene. Ethylene resins having a melting point lower than that of these propylene resins are used as a component of adhesive layer E or as an ethylene resin before modification, but are blended into base layer A and paper-like layers B-D. In addition to facilitating the stretching of the propylene resin that is the matrix resin of these layers,
The lamination strength between each layer can be made stronger.

The content of the inorganic fine powder is higher in the paper layer B-D than in the base layer A.
Increase the content of Since the base layer A is biaxially stretched and oriented, the size of the microvoids is also larger than that of the paper-like layer BD, which is uniaxially stretched and oriented. The base material layer A has the effect of balancing the vertical and horizontal strength of the label and preventing the label from tearing. Therefore, since the presence of excessive micropoid leads to a decrease in the strength of the base layer A, the content of the inorganic fine powder in the base layer A is preferably 30% by weight at most.

The content of the inorganic fine powder in the paper layer BD is 35 to 65% by weight, preferably 35 to 52% by weight, in order to improve printability and writability.

By blending inorganic fine powder, the printability of labels is improved.
Opacity is improved.

Although the paper-like layer C is not an essential constituent layer and can be provided as necessary, the presence of this paper-like layer C has the effect of further reducing curling of the label l.

The paper-like layer D is a composition consisting of 80 to 35% by weight of propylene resin and 20 to 65% by weight of inorganic fine powder,
The inorganic fine powder blended into this paper-like layer D has a specific surface area of less than 2.000-12.0cm27g, preferably 4.000-11.000cm27g, and an average particle size l2 of 1.0cm27g. A thickness of 8 to 8 μm, preferably 2 to 5 μm is used. The concentration of the inorganic fine powder in the paper-like layer D is usually 20
It is blended in a proportion of ~65% by weight, preferably 25-55% by weight. The paper-like layer D usually has a thickness of 1
It is laminated into the multilayer composite film 2 with a thickness of 10 μm or more, preferably 2 to 15 μm.

The paper-like layer D has a particle size of the inorganic fine powder blended from 1.8 to
By using particles with a large particle size of less than 8 μm and by making the wall thickness of the adhesive layer E thin, the unevenness created by the large particle size inorganic fine powder creates a space between the adhesive layer E and the hollow product for air release. Create gaps to improve air escape and prevent pristers from forming due to air pockets.

In the range of the inorganic fine powder blended into the paper-like layer D, the specific surface area is 2. If it is less than 000cm27g, the surface roughness will be too large and the adhesive area of the E layer adhesive layer to the surface of the hollow container will decrease, and there is a risk that it will peel off when the mold shrinks.
．． 000cm27g or more, air entrainment occurs because the surface has few irregularities. In addition, the average particle size is 1.8μ
If it is less than m, blisters will occur, and if it is 8 μm or more, the adhesive strength will decrease. Furthermore, if the concentration of the inorganic fine powder in the paper-like layer D is less than 20% by weight, air entrainment will occur due to the lack of surface unevenness, and if it is more than 65% by weight, the stretchability will be poor.

When the film thickness of the paper-like layer D is less than lun1, air entrainment occurs because it makes little contribution to the unevenness of the surface of the adhesive layer, which causes the occurrence of prister.

The adhesive layer E is a uniaxially stretched film layer of an ethylene resin with a melting point of 80 to 130°C and a thickness of 1 to 10 μm, preferably 2 to 8 μm, and its surface has a surface smoothness (as measured by JISP-8119). BEKK index) is 1.000
seconds or less, preferably 1 to 450 seconds, and the center line average roughness (Ra) is 0.5 to 5 μm, preferably 0.7 to 3.
It is 0 μm.

Ethylene resins used in the adhesive layer E include high-density polyethylene, low-density polyethylene, linear polyethylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid alkyl ester copolymer ( Alkyl group has 1 to 8 carbon atoms), ethylene/methacrylic acid alkyl ester copolymer (alkyl group has 1 to 8 carbon atoms), metal salt of ethylene-methacrylic acid copolymer (Zn.AI.Li .K.Na) .
Examples include ethylene resins such as styrene-modified ethylene resins.

If the melting point of the ethylene resin is less than 80° C., blocking will occur and automatic label feeding will be impaired.

Furthermore, if the temperature exceeds 130°C, adhesion to the hollow container, especially the surface of high-density polyethylene, becomes poor.

The thickness of the adhesive layer E needs to be 1 μm or more so that the film of the adhesive layer is melted by the heat of the molten polyethylene that is the balisong during blow molding, and the molded product and the label I are firmly bonded. Moreover, if it exceeds 10 μm, the label l will curl, making offset printing difficult, and it will be difficult to fix the label l to a mold, which is not preferable. The thickness of the adhesive layer E is preferably up to about twice the average particle diameter of the inorganic fine powder blended in the paper-like layer D.

The surface smoothness of the adhesive layer E is expressed as BEKK index i. The average roughness of the surface (Ral is 0.5 to 5 μm)
If it is outside the range, air dissipation during blow molding is insufficient and blisters often occur.

The surface roughness of the adhesive layer E is obtained by the unevenness of the inorganic fine powder particles of the paper-like layer D below it, but it can be made even rougher by combining this with the properties of the resin film used for the adhesive layer.

Such an adhesive layer E includes: a) 5 parts by weight of styrene in the presence of 100 parts by weight of an ethylene resin;
Styrene-modified ethylene resin obtained by polymerizing 0 to 400 parts by weight 10 to 70% by weight b) Melting point is 80
Examples include non-oriented films made of uniaxially stretched resin compositions containing 90 to 30% by weight of ethylene/acrylic acid alkyl ester copolymers and/or ethylene/methacrylic acid alkyl ester copolymers at ~130°C. .

The styrene-modified ethylene resin of component a) is prepared by suspending 100 parts by weight of ethylene resin particles in water, adding 50 to 400 parts by weight of styrene dropwise to this suspension in the presence of a polymerization initiator. It can be produced by turbid polymerization (JP-A-56-55433, JP-A-49-5473).
No. 50-127965).

Examples of the ethylene-based resin include low-density polyethylene, high-density polyethylene, medium-density polyethylene, linear polyethylene, and ethylene/vinyl acetate (vinyl acetate content: 8% by weight or less) copolymer, particularly those having a melting point of 80 to 135.
℃ is preferably used.

Even if styrene is used alone, some (50% by weight or less)
Acrylic acid, methacrylic acid, itaconic acid, maleic anhydride, acrylic acid lower alkyl ester (alkyl group has 1 to 8 carbon atoms), methacrylic acid lower alkyl ester (alkyl group has 1 to 8 carbon atoms), etc. may be replaced with

The ethylene/lower alkyl acrylic ester copolymer (the alkyl group has 1 to 8 carbon atoms) and the ethylene/lower alkyl methacrylic ester copolymer (the alkyl group has 1 to 8 carbon atoms) of component b) above.
If the alkyl group has 1 to 8 carbon atoms, the melting point is 80 to 130.
℃ is used.

This is mainly composed of ethylene and lower alkyl acrylate or lower alkyl methacrylate, and whether it is a binary copolymer or a tertiary copolymer, other than this It may also be a ternary or higher copolymer containing other vinyl monomers in a proportion of 8% by weight or less.

Specifically, ethylene/methyl acrylate copolymer, ethylene/ethyl acrylate copolymer, ethylene/probyl acrylate copolymer, ethylene/t-butyl acrylate copolymer, ethylene/methyl acrylate/meth Acrylic acid copolymer, ethylene/methyl acrylate/itaconic acid copolymer, ethylene/methyl acrylate/maleic anhydride copolymer, ethylene/methyl acrylate/lobetyl acrylate copolymer, ethylene/acrylic acid n- Butyl/methyl methacrylate copolymer, ethylene/ethyl methacrylate copolymer, ethylene/probyl methacrylate copolymer, ethylene/butyl methacrylate copolymer, ethylene/methyl methacrylate/acrylic acid/
A methacrylic acid copolymer, an ethylene/methyl methacrylate/2-ethylhexyl acrylate copolymer, an ethylene/ethyl acrylate/acrylonitrile copolymer, etc. can be used.

Preferably, it is 15 to 50% by weight.

The amount of component a) in the adhesive layer E is 10 to 70% by weight, preferably 15 to 50% by weight, and the amount of component b) is 90 to 3% by weight.
0% by weight, preferably 85-50% by weight.

The ethylene resin of the adhesive layer E may contain inorganic fine powder. The amount of inorganic fine powder is desirably 3% by weight or less, since it has the effect of imparting surface roughness and also reduces adhesion.

The surface of the adhesive layer E side of the label can be further roughened by embossing.

The wall thickness of the entire label l of the present invention is 30 to 300 μm, preferably 45 to 150 μm, and the wall thickness of the entire label is 30 to 300 μm, preferably 45 to 150 μm.
If the thickness is less than 0 μm, paper feeding and offset printing will be difficult, and if the thickness exceeds 300 μm, it will be economically disadvantageous.

9 The high-density polyethylene used as the material for the parison when the label of the present invention is placed in a mold and blow-molded includes ethylene homopolymer, ethylene/propylene random copolymer, and ethylene/butene-l copolymer. Polymers such as linear or branched polyethylene such as ethylene-propylene-butene-1 copolymer can be used. Furthermore, as the linear polyethylene, ethylene/butene-1 copolymer and ethylene/4-methylpentene-1 copolymer can be used.

As a means for fixing the label 1 to the mold, the same method as the conventional electrostatic adhesion method or reduced pressure (vacuum) method can be adopted.

During blow molding, the label 1 comes into contact with the molten polyethylene parison, but the paper-like layer B side of the label 1, which is offset printed, comes into contact with the mold and is cooled.
The surface of paper-like layer B does not melt. That is, the multicolor printing does not lose its sharpness, and it is attached to the molten polyethylene molded body under pressure without all of the polypropylene of the paper-like layer B in the label being melted. , the label 1 is prevented from shrinking or curling.

The temperature of the molten polyethylene parison when attaching the label 1 was 170 to 230°C, and the air blowing pressure during molding was 0.5 to 7.
Generally, it is kg/cm2G.

Although the label of the present invention uses a stretched film, there are no problems such as heat shrinkage or unclear printing, and the label can be firmly attached to the molded article. Furthermore, since polyethylene and polypropylene, which are highly water and chemical resistant, are used as the label material, the molded product with the label of the present invention can be used as a container for liquids such as shampoo, frozen liquid, motor oil, etc. without the label remaining. It will not peel off from the container body.

[Example] The label of the present invention will be specifically described below with reference to Examples.

Production example 1 of multilayer wood 2 film (1) Polypropylene manufactured by Mitsubishi Yuka ■ [Mitsubishi Noblen M
A-6J (trade name, melting point: 164°C) 81 parts by weight,
Mitsubishi Yuka ■ high-density polyethylene "Yukalon Hard ET"
-40J (trade name, melting point: 130°C, density: 0.95
0g/crrr) 3 parts by weight and 1.5μm particle size ground calcium carbonate, specific surface area: 15.000m2/g)
After melt-kneading 16 parts by weight of Composition A using an extruder, it was extruded into a sheet at a temperature of 250°C using a gouer, and the sheet was cooled to a temperature of about 50°C.

Next, this sheet was heated to 153° C., and then stretched 4 times in the longitudinal direction using the difference in peripheral speed between the roll groups to obtain a uniaxially stretched film.

(2) Separately, 52 parts by weight of polypropylene manufactured by Mitsubishi Yuka ■ [Mitsubishi Noblen MA-3J (trade name, melting point: 163°C)], high-density polyethylene with a density of 0.960 g/crrI1 (= Yucalon manufactured by Mitsubishi Yuka ■ Hard EY-40 4
) 3 parts by weight and Composition B2 consisting of 45 parts by weight of the same heavy calcium carbonate as above 2+11, and polypropylene (Mitsubishi Noblen MA-3J manufactured by Mitsubishi Yuka ■) 47
Part by weight, maleic anhydride (0.5% by weight) manufactured by Mitsubishi Yuka ■
5 parts by weight of grafted polypropylene, high density polyethylene (manufactured by Mitsubishi Yuka ■ [Yukalon Hard EY-40 J)
3 parts by weight and the same heavy calcium carbonate as in (1) above 4
Composition B, consisting of 5 parts by weight, is separately melt-kneaded using two extruders, and then each is supplied to one die and laminated in a tie to perform the step (1) above. The film was extruded and laminated on one side of the longitudinally stretched film produced in the above at a temperature of 250° C. so that the 81st layer side was on the outside.

(3) On the other hand, 52 parts by weight of polypropylene (manufactured by Mitsubishi Yuka ■ [Mitsubishi Noprene MA-3J), high-density polyethylene (manufactured by Mitsubishi Yuka ■ [Yukalon Hard EY-40J)]
Composition D consisting of 3 parts by weight and 45 parts by weight of heavy calcium carbonate with a specific surface area of 2.700 m27g and an average particle size of 8 μm, and low density polyethylene (Mitsubishi Yuka ■
Manufactured by Yucalon LM-40J. Density: 0.910) E
are melt-kneaded in separate extruders, then supplied to one tie, and after being laminated in the tie, the other side of the longitudinally stretched film A is heated at a temperature of 250°C so that the E layer side is on the outside. A sheet with a five-layer structure was obtained by melt lamination.

(4) This five-layer sheet was once cooled to 60°C, then reheated to a temperature of approximately 163°C, stretched 7 times in the transverse direction using a tenter, and then set at 165°C. After passing through the oven and setting the heat, the temperature is approximately 60℃.
After cooling and corona discharge treatment on layer B, the ears were slit so that the thickness of each layer [B1/B2/A/D/E] was 5 μm/15 gm/70 μm/5 μm/2.
A synthetic paper made of a multilayer resin film with a five-layer structure of μm (total thickness 97 μm) was obtained.

The liver KK index of the E layer is 10 seconds, and the average roughness (Ral is 1.9
It was μm.

Table 1 shows the physical properties of this five-layer multilayer resin film.

Examples 2 to 3 A multilayer resin film with a five-layer structure having the physical properties shown in Table 1 was obtained in the same manner as in Example 1 except that the thickness of the D layer was changed to 1.5 μm or 0.5 μm. .

Examples 4-6 As heavy calcium carbonate in layer D, specific surface area is 6.30
The procedure was carried out in the same manner as in Example 1, except that particles of 0 m27g and an average particle size of 3.6 μm were used, and the amounts used were changed to 45 parts by weight, 25 parts by weight, and 15 parts by weight.
A multilayer resin film having a five-layer structure having the physical properties shown in 1 was obtained.

Examples 7 to 9 The low density polyethylene of the E layer is made of ethylene/methyl acrylate copolymer (methyl acrylate content: 18% by weight), ethylene/vinyl acetate copolymer (vinyl acetate content: 2.8% by weight), or a straight chain line. A multilayer resin film having a five-layer structure having the physical properties shown in Table 1 was obtained in the same manner as in Example 4, except that the polyethylene film was changed to low-density polyethylene.

Example 1O~12 As heavy calcium carbonate in layer D, the specific surface area is 9.80
0 m 27 g and an average particle size of 2.2 μm, and the film thickness of the low density polyethylene of the E layer was 2 μm.
A multilayer resin film with a five-layer structure having the physical properties shown in Table 1 was obtained in the same manner as in Example 1 except that the thicknesses were changed to m, 8 μm, and LLLLm.

Examples 13 and 14 As heavy calcium carbonate in layer D, each has a specific surface area of 12
, 000 m2/g, and the average particle size is 1.8 g m
or has a specific surface area of 15. A multilayer resin film having a five-layer structure having the physical properties shown in Table 1 was obtained in the same manner as in Example 1 except that a film having a particle size of 000 m2/g and an average particle size of 1.5 μm was used.

Example 15 The low density polyethylene of the E layer is made of low density polyethylene 95
A multilayer resin with a five-layer structure having the physical properties shown in Table 1 was prepared in the same manner as in Example 1 except that the composition was changed to 5 parts by weight and 5 parts by weight of heavy calcium carbonate having a particle size of 1.5 μm. Got the film.

Nobel 5
1300 was applied, dried, and then multicolor offset printing was performed on the surface of this layer B. The label was then cut to 50 mm in length and 50 mm in width.

Labeling Production of hollow volume ゜Vertical 5 manufactured in Examples 1 to 1O and Comparative Examples 1 to 5
After fixing a label of 0 mm and width 50 mm with the paper-like layer side in contact with a mold at 41°C by vacuum depressurization, the high-density polyethylene "Yukalon Hard EY-4D" manufactured by Mitsubishi Yuka ■ was used.
J was extruded into a parison shape at 180°C, and then the parison was sandwiched between molds cooled with cooling water at 20°C at a flow rate of 15j/min, and compressed air at a pressure of 5kg/cm2 was supplied into the parison. While blow molding, the molded body was cooled using a mold and opened to obtain a labeled hollow container (1st edition wall thickness) with a body diameter of 60 mm and a height of 200 mm.

Air entrainment was evaluated and label adhesive strength was measured for the obtained 20 labeled hollow containers. The results are shown in Table-1.

Note that air entrainment was evaluated and label adhesive strength was measured by the following method.

(1) For each air-entrained container, the attached label indicates that all air-entrained
5 points for those with air entrainment of 10% or less of the label area, 3 points for those with air entrainment in an area of 10% or more but less than 20%, 3 points for those with air entrainment of 10% or more, 50%
A total score of 20 containers is evaluated, with 2 points for containers with air entrapment in an area of less than 50%, and 1 point for containers with air entrainment in an area of 50% or more, resulting in a total score of 90 points. Those above were given an O, and those below 90 points were given a ×.

(2) Label adhesion strength: Cut out 10 test pieces of 15 mm width from each of the obtained 5 labeled containers, peel off a portion of the attached label, and use a Tensilon tensile tester at a speed of 300 mm/min for peel strength. I was looking for something. The peel strength is the average value of 10 test pieces.
Those with a weight of 715 mm or less were marked as ×, and those with a weight of 100 g and 715 mm or more were marked as ○.

Note that an adhesive strength of 100 g or less means an adhesive strength that causes peeling when the label-attached portion of the obtained container is pressed by hand, and is an adhesive strength level that causes problems in practical use.

[Effects of the Invention] The label of the present invention roughens the surface of the adhesive layer due to the roughness of the surface of the paper-like layer that joins the adhesive layer of the label, and creates a rough surface between the parison and the adhesive layer during ζ blow molding. forming a gap,
The presence of this gap facilitates the dissipation of air from the surface when the adhesive layer is melted by the heat of the parison, preventing air pockets from forming between the hollow product and the label, and preventing the occurrence of blister. be able to.

Therefore, even when using a hollow mold whose inner surface is plated or mirror-finished, it is possible to effectively prevent the occurrence of blisters and wrinkles, and to produce hollow containers with labels that have a glossy surface and an excellent appearance. It can be molded with good yield.

Further, although the label of the present invention uses a stretched film, there are no problems such as heat shrinkage or unclear printing, and the label can be firmly attached to the molded article. Furthermore, since polyethylene and polypropylene, which are highly water and chemical resistant, are used as the label material, the molded product with the label of the present invention can be used as a container for liquids such as shampoo, frozen liquid, motor oil, etc., without the label. will not peel off from the container body.

[Brief explanation of drawings]

FIG. 1 shows a cross-sectional view of a label according to an embodiment of the invention. 1: Label 2: Multilayer composite film 3: Printing
A: Base material layer B. C. D: Paper-like layer E: Adhesive layer Applicant: Oji Yuka Synthetic Paper Co., Ltd.

Claims (1)

[Claims] (1) In a label composed of a multilayer resin film, the multilayer resin film is made of a resin composition containing 5 to 30% by weight of inorganic fine powder and 95 to 70% by weight of a propylene resin. On one side of the axially stretched film base layer (A), a paper-like layer ( B) is laminated on one side of the base layer (A) opposite to the paper-like layer (B), and has a specific surface area of 2,000 to 12,000 cm^2/g and an average particle size of 1.8 to 8 μm inorganic fine powder 2
0-65% by weight and propylene resin 80-35% by weight
A paper-like layer (D) made of a uniaxially stretched film of a resin composition containing a proportion of
A laminate consisting of at least four layers, including an adhesive layer (E) with a wall thickness of 1 to 10 μm made of a uniaxially stretched film of an ethylene resin with a melting point of 80 to 130°C. Measured surface smoothness is 1.0
00 seconds or less, center line average roughness (Ra) is 0.5-5μ
A label characterized by m.