JP3184595B2 - Adhesive composition and laminate using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an adhesive composition and a laminate using the same. More specifically, the present invention relates to an adhesive composition exhibiting good moldability and adhesiveness when laminating a saponified product of ethylene and vinyl acetate copolymer on paper, and a laminate using the same.

[0002]

2. Description of the Related Art Conventionally, a composition containing a substantially linear low-density polyethylene and a modified ethylene-based polymer as an adhesive for laminating a saponified product of ethylene and vinyl acetate copolymer on paper. Is used.

[0003] However, such a composition does not particularly have sufficient adhesiveness to paper, and it is desired to increase the adhesiveness.

In laminating, the adhesive composition is generally co-extruded with, for example, a saponified product of ethylene and a vinyl acetate polymer, and combined with the paper so that the layer of the adhesive composition is in contact with the paper. The process is advantageously carried out industrially. However, the above-mentioned conventional composition is liable to cause necking and ear swelling during co-extrusion, and particularly when the extrusion speed is increased, this becomes more and more remarkable, and has a problem to be improved.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an adhesive composition. Another object of the present invention is to provide an adhesive composition having enhanced adhesion to paper.

It is a further object of the present invention to provide an improved extrudate wherein the degree of necking and ear wobbling is greatly improved when extruded, for example, with a saponified ethylene and vinyl acetate copolymer. An object of the present invention is to provide an adhesive composition exhibiting moldability. Still another object of the present invention is to provide a laminate using the adhesive composition of the present invention. Still other objects and advantages of the present invention will be apparent from the following description.

[0007]

According to the present invention, the above objects and advantages of the present invention include: (A) a substantially linear low density polyethylene; (B) a high pressure low density polyethylene; (C) an ethylene polymer modified with an unsaturated carboxylic acid or a derivative thereof, wherein the ethylene polymer is an ethylene homopolymer or based on the total number of moles of ethylene and other α-olefins; The α-olefin other than ethylene is a random copolymer of ethylene and other α-olefins occupying 10 mol% or less, and (D) a tackifier; ), Based on the total weight of component (B), component (C) and component (D),
80% by weight, component (B) is 1 to 50% by weight, and component (C) and component (D) are each independently 1 to 30% by weight.
It is achieved by an adhesive composition characterized in that it occupies by weight.

[0008] The adhesive composition of the present invention, as described above,
It comprises four components (A), (B), (C) and (D). The substantially linear low density polyethylene of component (A) preferably has a density of 0.94 g / cm ³ or less and a
It has a melt index value of ５０50 g / 10 min. This linear low-density polyethylene is a copolymer of ethylene and α-olefin, and the content of α-olefin is 10 mol% or less. As the α-olefin, one having 3 to 20 carbon atoms is usually used. Such olefins include, for example, propylene, 1-butene, 1-hexene,
4-methyl-1-pentene, 1-octene, 1-decene and the like.

The high-pressure low-density polyethylene of component (B) preferably has a density of 0.93 g / cm ³ or less and a density of 0.93 g / cm ³ or less.
It has a melt index value of 1 to 50 g / 10 minutes.

The component (C) is obtained by modifying an ethylene homopolymer with an unsaturated carboxylic acid or a derivative thereof, or based on the total mole number of ethylene and other α-olefin, other than ethylene. A random copolymer in which an α-olefin accounts for 10 mol% or less, preferably 5 mol% or less, is modified with an unsaturated carboxylic acid or a derivative thereof.

The unsaturated carboxylic acids or derivatives thereof include, for example, acrylic acid, maleic acid, fumaric acid,
Tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, nadic acid (endocis-
Unsaturated carboxylic acids such as bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylic acid); and derivatives thereof, such as acid halides, amides, imides, anhydrides and esters.

Specific examples of such derivatives include, for example,
Maleenyl chloride, maleimide, maleic anhydride, citraconic anhydride, monomethyl maleate, dimethyl maleate, glycidyl maleate and the like can be mentioned. Among these, unsaturated dicarboxylic acids or acid anhydrides thereof are preferable, and maleic acid, nadic acid or acid anhydrides thereof are particularly preferably used.

The α-olefin random copolymer before modification is composed of ethylene and α-olefin other than ethylene in which the α-olefin other than ethylene accounts for 10 mol% or less based on the total moles of ethylene and other α-olefin. And a random copolymer of

As α-olefins other than ethylene,
Α-olefins having 3 to 20 carbon atoms are preferably used. Examples of the α-olefin include propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-tetradecene,
1-octadecene and the like. These α-olefins may be used alone or in combination of two or more.

The α-olefin accounts for 10 mol% or less, preferably 5 mol% or less based on the total number of moles of ethylene constituting the random copolymer. If the amount of the α-olefin exceeds 10 mol%, blocking due to stickiness is likely to occur and handling becomes difficult, which is not preferable.

The ethylene polymer (C) modified with an unsaturated carboxylic acid or a derivative thereof is preferably from 0.05 to 15% by weight, more preferably from 0.1 to 15% by weight, based on the ethylene polymer before modification. It is graft-modified with 10 to 10% by weight of an unsaturated carboxylic acid or a derivative thereof.

Further, the modified ethylene polymer (C)
Preferably has a melt flow rate (MFR) of 0.1 to
50 g / 10 min, more preferably 0.3 to 30 g MFR
/ 10 minutes. Melt flow rate is ASTM D1
238 (190 ° C., load 2160 g).

The tackifier of component (D) is preferably a solid amorphous polymer, which is usually used as a tackifier resin in the fields of pressure-sensitive adhesive tapes, paints and hot melt adhesives.

The following resins can be exemplified depending on the source of the monomer to be polymerized. For example, petroleum, C ₄ fraction obtained by decomposition of naphtha, C ₅ fractions, mixtures thereof or fractions of these optional, for example, a C ₅ distillate isoprene and 1,3-pentadiene and the like main raw Aliphatic hydrocarbon resin; aromatic hydrocarbon resin mainly composed of styrene derivative and indene in C ₉ fraction obtained by cracking of petroleum, naphtha, etc .; C ₄ · C ₅
Fraction arbitrary fraction and C ₉ fraction obtained by copolymerizing aliphatic aromatic copolymer hydrocarbon resins; aromatic alicyclic hydrocarbon resins hydrocarbon resins obtained by hydrogenating; aliphatic, alicyclic Synthetic terpene-based hydrocarbon resin having a structure containing aromatic and aromatic compounds; terpene-based hydrocarbon resin derived from α, β-pinene in turpentine oil; Malon indene-based hydrocarbon resin; low molecular weight styrene-based resin and rosin-based hydrocarbon resin.

The adhesive composition of the present invention contains 30 to 80% by weight of the component (A) based on the total weight of the components (A), (B), (C) and (D). (B)
The component accounts for 1 to 50% by weight, and the components (C) and (D) both independently account for 1 to 30% by weight.

When the amount of the component (B) is less than 1% by weight, the effect of preventing necking and ear wobbling is not obtained. The preferable ratio of the component (B) is 1 to
30% by weight. If the amount of the component (C) is less than 1% by weight, no adhesiveness is exhibited, and if it exceeds 30% by weight, the adhesiveness does not increase, resulting in a decrease in economic efficiency. If the amount of the component (D) is less than 1% by weight, adhesiveness is not exhibited, and if it exceeds 30% by weight, blocking is liable to occur, which causes a problem in handling.

The adhesive composition of the present invention may further contain, in addition to the above components, a random copolymer (F) of ethylene and an α-olefin. The component (F) preferably accounts for 30% by weight or less based on the total weight of the components (A) to (D) and the component (F).

The random copolymer (F) of ethylene and α-olefin preferably has a crystallinity of 30% by weight or less, more preferably 25% by weight or less.

As the α-olefin, an α-olefin having 3 to 20 carbon atoms is preferably used. Examples of such α-olefins include propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene,
-Decene, 1-tetradecene, 1-octadecene and the like. These α-olefins may be used alone or
More than one species can be used together.

The α-olefin accounts for preferably 5 to 55 mol%, more preferably 10 to 55 mol%, based on the total number of moles of ethylene constituting the random copolymer.

As the random copolymer of ethylene and α-olefin, for example, a random copolymer of ethylene and propylene and a random copolymer of ethylene and 1-butene are particularly preferably used.

The adhesive composition of the present invention also adheres to, for example, high-pressure low-density polyethylene (HPLDP) and the like, and particularly exhibits excellent adhesiveness to saponified ethylene / vinyl acetate copolymer and paper. Thus, according to the present invention, there is advantageously provided a laminate wherein a layer of saponified ethylene / vinyl acetate copolymer, a layer of the adhesive composition of the present invention and paper are present in this order.

The laminate of the present invention is industrially advantageous, for example, by co-extrusion of a saponified ethylene / vinyl acetate copolymer and the adhesive composition of the present invention, and after co-extrusion, is combined with paper. Can be manufactured. The extrudability of the adhesive composition of the present invention is good, and therefore, the degree of necking and ear wobble is remarkably improved even in the case of co-extrusion as described above.

[0029]

The present invention will be described in more detail with reference to the following examples.
The present invention is not limited to these. Example 1 (1). A substantially linear low-density polyethylene (Ultzex ^(R) 20100J manufactured by Mitsui Petrochemical Industries, Ltd.) 7
5 parts by weight, 10 parts by weight of high-pressure low-density polyethylene (Mirason ^(R) 11P, manufactured by Mitsui Petrochemical Industries, Ltd.), tackifier (Alcon P125, petroleum resin manufactured by Arakawa Chemical Co., Ltd.)
0 parts by weight and high-density polyethylene graft-modified with maleic anhydride (density = 0.96 g / cm ³ , MFR =
5 g of 4 g / 10 min, graft ratio of 2 wt%) was melt-mixed at 200 ° C. using an extruder to obtain pellets.

(2). The obtained pellets (hereinafter referred to as MPE) and a saponified product of ethylene and vinyl acetate copolymer (manufactured by Kuraray Co., Ltd., Eval EP-E105B, hereinafter referred to as EVOH) in the following apparatus: 2 layers Extrusion Laminator Extruder made by Sumitomo Heavy Industries: 65 mmφ for MPE, L / D = 32 For EVOH 65 mmφ, L / D = 32 Black box: Rectangular pipe merging method Merging angle 30 degrees MPE side straight, EVOH side side merging Dies: Straight Using a teardrop type manifold, the following molding conditions: Thickness configuration MPE / EVOH (EP-E105B)
= 10/30 μ, adherend Kraft paper, basis weight 50 g / m ² Co-extrusion and lamination were performed under the following conditions: molding temperature 230 ° C., take-off speed 80 m / min.

The following items were evaluated for the obtained laminate. Lamination suitability: Degree of neck-in Adhesion: Paper / MPE T-peel strength (30
0 mm / min) MPE / EVOH T-peel strength (300 mm / m
in) The results are shown in Table 1.

Example 2 An experiment was conducted in the same manner as in Example 1 except that the amount of the substantially linear low-density polyethylene was changed to 65 parts by weight and the amount of the tackifier was changed to 20 parts by weight. . The results are shown in Table 1.

Example 3 An experiment was conducted in the same manner as in Example 1 except that the amount of the substantially linear low-density polyethylene was changed to 55 parts by weight, and the amount of the high-pressure low-density polyethylene was changed to 30 parts by weight. Table 1 shows the results
It was shown to.

Comparative Example 1 An experiment was carried out in the same manner as in Example 1 except that the amount of the substantially linear low-density polyethylene was changed to 85 parts by weight and the high-pressure low-density polyethylene was not used. The results are shown in Table 1.

Comparative Example 2 An experiment was conducted in the same manner as in Example 1 except that the amount of the substantially linear low-density polyethylene was 85 parts by weight and no tackifier was used. The results are shown in Table 1.

[0036]

[Table 1]

Example 4 (1). A substantially linear low-density polyethylene (Ultzex ^(R) 25100J manufactured by Mitsui Petrochemical Industries, Ltd.) 6
5 parts by weight, 10 parts by weight of a random copolymer of ethylene and propylene (Tuffmer P0280 manufactured by Mitsui Petrochemical Industry Co., Ltd., 80 mol% of ethylene, 20 mol% of propylene),
Graft modified with 10 parts by weight of high-pressure low-density polyethylene (Mirason ^(R) 11P manufactured by Mitsui Petrochemical Industries, Ltd.), 10 parts by weight of tackifier (Alcon P125, petroleum resin manufactured by Arakawa Chemical Co., Ltd.) and maleic anhydride. High density polyethylene (density = 0.96 g / cm ³ , MFR = 4 g / 10
5 parts by weight of a graft ratio 2% by weight) were melt-mixed at 200 ° C. using an extruder to obtain pellets. (2). The same operation as in Example 1. (2) was performed on the obtained pellets. The results are shown in Table 2.

Examples 5 to 8 and Comparative Examples 3 to 5 In the same manner as in Example 1. (1), an adhesive composition having the composition shown in Table 1 was prepared. A laminate was prepared in the same manner. The results are shown in Table 2.

[0039]

[Table 2]

[0040]

Continuation of the front page (56) References JP-A-61-81447 (JP, A) JP-A-4-23844 (JP, A) JP-A-2-252745 (JP, A) JP-A-64-9255 (JP) , A) (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 23/04 B32B 27/10 C08J 5/12 C08L 23/26

Claims (4)

(57) [Claims] 1. An ethylene-based polymer modified with (A) a substantially linear low-density polyethylene, (B) a high-pressure low-density polyethylene, (C) an unsaturated carboxylic acid or a derivative thereof. The system polymer is ethylene homopolymer or ethylene and other α-olefins in which the α-olefin other than ethylene accounts for 10 mol% or less based on the total mole number of ethylene and other α-olefins. And (D) a random copolymer of
And (E) 30 to 80% by weight of the component (A) based on the total weight of the components (A), (B), (C) and (D). , (B)
1 to 50% by weight of the component, and (C) component and (D)
An adhesive composition, wherein each component independently accounts for 1 to 30% by weight. 2. The adhesive composition according to claim 1, wherein (F) ethylene and α
The composition of claim 1, further comprising a random copolymer of olefins, wherein said component (F) accounts for not more than 30% by weight, based on the total weight of said components (A) to (D) and (F). The adhesive composition according to any one of the preceding claims. 3. A laminate wherein a layer of saponified ethylene / vinyl acetate copolymer, a layer of the adhesive composition of claim 1 and paper are present in this order. 4. A laminate wherein a layer of saponified ethylene / vinyl acetate copolymer, a layer of the adhesive composition of claim 2 and paper are present in this order.