JPH024507A - Laminate for offset printing - Google Patents

Abstract

PURPOSE:To exfoliate a substance to be printed from a reinforcing material without leaving an adhesive on the substance to be printed, by making an exfoliation strength between the material and an adhesive layer larger than one between the adhesive layer and the substance to be printed, when the substance to be printed is laminated on the reinforcing material through the intermediary of a hot melt type adhesive. CONSTITUTION:As for a first layer A of a laminate for offset printing, textile, knit or a film is used as a material for a substance to be printed. As adhesive of a second layer B is of a hot melt type and polyolefin, polyamide or polyurethane is used therefor. A third layer C is made up of a reinforcing material and paper, synthetic paper or the film is used therefor. While an exfoliation strength between the first and second layers is made to be 10 to 700g/inch, the strength between the second and third layers is made still larger, and the flexural stiffness of an entire laminate is made to be 0.40g.cm<2>/cm or above.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a laminate for offset printing, more specifically a laminate in which a printing material that is difficult to print on alone is lined with a reinforcing material, and can be printed with high precision,
The present invention relates to a laminate for offset printing that allows smooth peeling of a printing material from a reinforcing material after printing without any trouble.

BACKGROUND OF THE INVENTION Offset printing is frequently used to print multicolor precision printed materials such as maps that require highly accurate printing.

The printing materials used in such offset printing can be broadly classified into rolled materials and sheet materials depending on the form of supply to the printing press. In the case of a rolled body, it may not have sufficient strength or hardness because it is thin, or it may not have inherent strength or hardness, or it may be easily expanded or contracted and deformed, etc. If the material is not suitable for printing, it is first bonded with other Nli strong color materials using an adhesive to give it the strength, hardness (stiffness), and dimensional stability necessary for the printing process, then printed, and then reinforced. The process is to peel it off from the material and return it to a single printing medium. In addition, when the printing material is a sheet material, there are no restrictions on printing workability due to the thickness and elasticity of the roll, but if the size exceeds a certain level, depending on the material, printing workability is not restricted. worsens,
A similar process of lamination, printing, and peeling is employed.

When performing such steps, peeling is an important step, but conventionally, various troubles have occurred during peeling. In other words, peeling does not occur at the interface between the printing material layer and the adhesive layer, peeling occurs at the interface between the reinforcing material layer and the adhesive layer, or breakage occurs inside the adhesive layer and peeling occurs at that part. In some cases, the adhesive, reinforcing material, etc. may remain on the printed material side after peeling off, due to damage or destruction of the reinforcing material layer. Such troubles tend to occur when using conventionally used water-based or solvent-based adhesives, for example, when the adhesive penetrates into the printing material layer and the anchoring effect causes the printing material layer to This is due to the fact that the adhesive force between the adhesive layer and the adhesive layer is strengthened. If adhesive remains, it may stick between the surfaces of the printing material when it is rolled up or stacked, it may stick to other objects after it is made into individual products, or it may stick between the surfaces when it is folded. It becomes a problem. Furthermore, there were cases where the adhesive strength at the interface was too strong and it could not be peeled off smoothly, or because it could not be peeled off smoothly, a large amount of force was applied, resulting in the printing material itself tearing. .

Problems to be Solved by the Invention Accordingly, it is widely desired that a laminate for offset printing 11, which can be smoothly peeled off from a printing material after printing using a surface marking procedure, and which will not leave any adhesive on the printing material side, is widely desired. There is.

Rounding means to solve the problem n: In view of i article + / 1, as a result of intensive research, the aqueous emulsion type, which was conventionally classified as 11]
The present invention was completed by discovering that the problem of α-outer moe can be solved by using a specific type of adhesive instead of solvent-based paint-based adhesives or general adhesives such as starch paste. I ended up doing it.

That is, the present invention provides a first layer consisting of 1611 pieces of his seal,
A laminated structure consisting of a second layer made of a hot melt adhesive provided under the first layer, and a third layer made of a reinforcing material provided below the second layer is prepared; and the second layer, the peel strength between the second layer and the third layer is greater than the peel strength between the first layer and the second layer, and the peel strength between the second layer and the third layer is greater than the peel strength between the first layer and the second layer. The object of the present invention is to provide a laminate for offset printing, which is characterized in that the feel of the entire body is 0.401 i1·cm''/ax or more in terms of bending rigidity.

The present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing the laminate for offset printing of the present invention. In the drawings, A represents the printing material layer, B represents the pot-melt adhesive layer, and C represents the h1111 strong material.

The present invention is useful for printing materials that are not suitable for printing work on their own.
It is applied to cases where the material is thin, tends to be easily damaged by printing pressure, or lacks hardness. Therefore, the first layer (
The printing material forming A) is a drastic material. Examples of the form of the material include woven fabrics, knitted fabrics, paper, films, sheets, non-woven fabrics, and porous coatings of these ropes, but are not particularly limited.

The type of material is not particularly limited, and any material that is normally used as a printing material suitable for offset printing may be used.

A hot melt adhesive is used as the adhesive forming the second layer ([3). Examples of hot-melt adhesives include polyolefin-based, polyamide-based, polyurethane-based, polyester-based, EVA-based, and PVc-based adhesives.

As the H17 strong material forming the third layer (C), paper, synthetic paper, film, woven fabric, non-woven fabric, metal foil, uniform base material with equal area (4) can be used, but paper is suitable from the cost point of view. be.

The materials and adhesives described above are used for each layer, but the peel strength of the laminate for offset printing of the present invention is within a specific range. That is, the interfacial peel strength between the first layer and the second layer is 10 to TO (N/inch, preferably 50 to 30
It is within the range of 0 g/inch, and the interfacial peel strength between the second layer and the third stone is greater than the interfacial peel strength between the first layer and the second layer. The peel strength in the range of lO to 7009/inch is required to be 10 g/inch or more to prevent peeling due to printing pressure etc. during printing, and 700 g/inch or less to peel off the printing material smoothly after printing. It is requested because it is desirable. In addition, if it is expected that the interfacial peel strength between the first and second layers will be high if the bonding is performed as is, the adhesion may be improved by placing a small amount of a release agent such as silicone on the bonding surface. It is effective to use a first layer that has been treated to reduce the force to the desired strength, which is a simple four.

The peel strength in the above size range and the relative relationship between the peel strength at the two interfaces are determined by selecting and combining the types of materials forming the first and third layers and the type of hot melt adhesive. This can be achieved as appropriate. Examples of such combinations include using the above-mentioned materials as the third layer, and using a porous nylon film/EVA hot-melt adhesive with release treatment applied to the adhesive side as the first/second layers; Nylon taffeta coated with porous nylon on one side/EVA hot melt adhesive, nylon taffeta coated with porous nylon on both sides/E
VA hot melt adhesive, nylon taffeta/polyurethane hot melt adhesive coated with porous nylon on one surface side, polyester taffeta/EVA hot melt adhesive coated with porous urethane on one surface side, Examples include combination U using a nonwoven fabric coated with porous nylon/EVA pot-melt adhesive. In addition, within A layer, B layer and C
It goes without saying that an adhesive should be selected whose intralayer peel strength (fracture strength) is greater than the interlayer interfacial peel strength.

Further, in the present invention, the texture of the laminate as a whole is within a specific range. In the present invention, this texture is expressed in terms of bending rigidity. Bending stiffness is the rotational moment required to give a unit change in curvature to a sample.
1ll11 can be determined with S-FB2. The laminate of the present invention has such bending rigidity that the sample was measured under the following conditions: temperature: 20°C, humidity = 65%, sample width: 20CJI,
Clamp spacing:! c2, curvature increase rate: Q, 5cr'
0 when measured in /second. = 109·am'/ctx or more. This invention is mainly applicable to large-sized printing materials, that is, in terms of lithographic size, A-row book size (625x880) and B-row book size (765x1
085), 46th edition (788x1091), chrysanthemum edition (636
The hardness described above is required based on the hardness required for printing on such large plates.

The offset printing laminate of the present invention described above can be obtained by selecting the combination of materials and adhesives as described above and laminating them by a conventional method.

Lamination methods include, for example, extrusion lamination in which a hot melt adhesive is melted and extruded, a force rendering method, and a coating method.

When bonding with a hot melt adhesive during such lamination, the adhesive is bonded in a molten state at a temperature above the melting point, but the temperature decreases at the interface with the printing material layer, resulting in an increase in melt viscosity and a water-based adhesive. or there is no penetration into the substrate layer as in the case of solvent-based adhesives, thereby also creating an anchoring effect, thus reducing the adhesive's appearance during peeling.
No residue remains on the body layer side, and a good peeling effect can be obtained. TalΔ conditions, such as melting temperature and material supply rate, can be appropriately selected depending on the selected material and adhesive.

The laminate for offset printing of the present invention is a printing element (e) that can be peeled off from the 11 HLI strong materials without trouble, and can be obtained by offset printing according to a conventional method. Print, peel off and leave the mark till
Can it be used as an object? For example, a porous nylon sort with a thickness of 30 to 500 J1 and a medium size of 40 to 120 cm, which has a conical shape but has excellent printability, can be made into the laminate of the present invention. By applying precision multicolor printing and peeling, it is possible to create a map with wet strength that can be safely used outdoors. In addition, the laminate of the present invention can be used for fabrics that normally have a large elongation, or for nylon fabrics that expand and contract in the air as the moisture content changes, so that register marks, so-called register marks, may not match due to changes in the environment (humidity) during printing. By doing so, various types of printing can be applied and then peeled off to create calendars, hanging curtains, etc.
It can be used as a tapestry, map, p, o, p, etc.

Effects of the Invention The laminate for offset printing of the present invention has an excellent ability to perform the peeling operation smoothly without leaving any adhesive on the side of the printing material when the printing material is peeled off from the reinforcing material after printing. It is a printing material.

The present invention will be explained in more detail with reference to Examples below.

Example 1 A nylon fabric coated with porous nylon on one side of the surface, 99 μm thick and 105 cx as the printing material, a high-quality paper with a thickness of 150 μm and 100 cm inside as the reinforcing material, and an EVA type as the pot-melt adhesive. using
According to a conventional method, extrusion lamination was performed at an extrusion temperature of 130° C., and the product was wound up to obtain a laminate for offset printing of the present invention.

Multicolor precision printing was performed on this printing material by offset printing according to a conventional method. The printing operation was carried out smoothly, and the printed hindlimb print layer was peeled off. At this time, as shown in FIG. 2, peeling occurred only at the interface between the stamp Bl+ body layer and the adhesive layer, and no adhesive was observed on the printing material side. Note that the peel strength was 150 g/inch.

Example 2 The adhesive side of a nylon fabric with a thickness of 200μ and a medium size of 1000Rx was treated with 0.29/x” as a printing material, and then a reinforcing material with a thickness of 100μ and a width of 900za was applied.
Using high-quality paper and a polyurethane type hot-melt adhesive, extrusion lamination was performed at an extrusion temperature of 150° C. according to a conventional method to obtain a laminate for offset printing of the present invention.

Offset printing was performed on this printing material according to a conventional method. The printing work was carried out smoothly, and the film was peeled off after printing. The peel strength was +0.09/inch, and the process was smooth and no adhesive was observed on the side of the printing material.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view schematically showing the laminate for offset printing of the present invention, and FIG. 2 is a view schematically showing the laminate for offset printing of the present invention during peeling. The symbols in the drawings have the following meanings. A: Printed material layer, B: Hot melt adhesive layer, C: Reinforcement material layer

Claims (3)

[Claims] (1) A first layer made of a printing material, a second layer made of a hot melt adhesive provided under the first layer, and a third layer made of a reinforcing material provided below the second layer. The peel strength between the first layer and the second layer is 10 to 7.
00 g/inch, the peel strength between the second layer and the third layer is greater than the peel strength between the first layer and the second layer, and the texture of the laminate as a whole is expressed by the bending rigidity. Te 0.
A laminate for offset printing characterized by having a weight of 40 g/cm^2/cm or more. (2) The laminate for offset printing according to claim (1), wherein the first layer is made of porous plastic. (3) The laminate for offset printing according to claim (2), wherein the first layer is made of porous nylon.