JPS5840491B2 - Method of manufacturing laminates - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a laminate with good adhesion between a polyolefin layer and a metal foil.

Laminated boards with metal foil laminated on both sides of a polyolefin layer are widely used for civil engineering, architecture, furniture, and decoration.

As a method of improving the adhesion between the polyolefin layer and metal foil of these laminates, there are methods of modifying the polyolefin, such as blending unsaturated carboxylic acids or derivatives thereof into the polyolefin, or using these monomers. Graft polymerization is being carried out.

It is also known to treat the surface of metal foil with acid or the like.

By applying these methods to a laminate, high interlayer adhesion can be obtained.

However, laminates may be cold worked or exposed to harsh conditions, and in such cases, some of the laminates may lose their adhesive strength over time.

Furthermore, in the above-mentioned methods, the adhesion is often greatly influenced by the temperature conditions during molding, and there is a drawback that the molding temperature range is small.

The present inventors have arrived at the present invention as a result of studying a method for efficiently manufacturing a laminate that has even better adhesive strength and excellent durable adhesiveness even under severe usage conditions.

That is, the present invention provides a method for manufacturing a laminate by laminating metal foils on both sides of a polyolefin layer.
Modified polyolefins 99 to 70 in which part or all of the polyolefin is grafted with at least one or more monomers selected from unsaturated carboxylic acids or derivatives thereof on both sides of a polyolefin sheet melted at 0°C or lower.
The present invention relates to a method for producing a laminate with good adhesiveness, which comprises bonding metal foil under pressure with an adhesive layer comprising 1 to 30 parts by weight of a hydrocarbon elastomer.

The polyolefins used as raw materials for the core material polyolefin sheet and the adhesive layer modified polyolefin include ethylene,
Propylene, 1-butene, 1-pentene, 3-methyl-
Homopolymers of α-olefins such as 1-butene, 1-hexene, and 4-methyl-1-pentene, or copolymers of one of the above monomers with 10 mol% or less, preferably 7 mol% or less of other α-olefins. A polymer or a mixture thereof with a crystallinity of 25% or more by X-ray analysis,
Further, there are copolymers of the above α-olefins and acyloxy, especially acetoxy substituted substances, such as vinyl acetate, or saponified products thereof.

Among these, medium-low density polyethylene, polypropylene, and even density 0.910! 9/cc or 0.970
9/cc, melt index (190'C) 0.0
Preferably, 5 to 100 polyethylene is used.

The modified polyolefin which is a component of the adhesive layer is produced by graft-modifying part or all of the above polyolefin with an unsaturated carboxylic acid or a derivative thereof.

Unsaturated carboxylic acids include acrylic acid, methacrylic acid,
Examples include fumaric acid, maleic acid, itaconic acid, and citraconic acid.

Derivatives of unsaturated carboxylic acids include acid anhydrides, esters, amides, imides, metal salts, etc., such as maleic anhydride, citraconic anhydride, itaconic anhydride, methyl acrylate, methyl methacrylate, and ethyl acrylate. , ethyl methacrylate, butyl acrylate, butyl methacrylate, glycidyl acrylate, glycidyl methacrylate, monoethyl maleate, diethyl maleate, monomethyl fumarate, dimethyl fumarate, monomethyl itaconate, diethyl methconate Ester, acrylamide, methacrylamide, maleic acid monoamide, maleic acid diamide, maleic acid-N-monoethylamide, maleic acid-N
.

N-diethylamide, maleic acid-N-monobutylamide, maleic acid-N,N-dibutylamide, fumaric acid monoamide, fumaric acid diamide, fumaric acid-N-monoethylamide, fumaric acid-N,N-diethylamide, fumaric acid -N-monobutylamide, N-fumaric acid, N-dibutylamide, maleimide, N-butylmaleimide, N-phenylmaleimide, sodium acrylate, sodium methacrylate, potassium acrylate, potassium methacrylate, etc. .

Among these, it is most preferred to use maleic anhydride.

Various known methods can be used to graft the monomer onto the polyolefin.

For example, it is carried out by heating the polyolefin and the grafting monomer at high temperature in the presence or absence of a solvent with or without the addition of a radical initiator.

Other vinyl septamers such as styrene may be present during the reaction.

The amount of the graft monomer grafted onto the polyolefin (hereinafter referred to as graft ratio) is preferably adjusted to be in the range of 10-4 to 3% by weight.

The polyolefin may be partially or completely grafted, but from an industrial production point of view, a modified polyolefin with a grafting rate of 10-2 to 6% by weight is produced in advance, and then It is preferable to mix the modified polyolefin with the unmodified polyolefin because the concentration of the graft monomer in the composition can be adjusted appropriately.

What is the hydrocarbon elastomer that is the other component of the adhesive layer?
For example, polyisobutylene, ethylene-propylene rubber,
These include ethylene-1-butene rubber, butyl rubber, butadiene rubber, styrene-butadiene rubber, ethylene-butadiene rubber, and imprene rubber.

Among these, ethylene-propylene 5 Most preferred are rubber and polyisobutylene.

The polyolefin layer and adhesive layer of the core material used in the present invention contain heat-resistant stabilizers, weather-resistant stabilizers,
A lubricant, an antistatic agent, a nucleating agent, a pigment, a dye, a flame retardant, an antiblocking agent, a slip agent, etc. may be blended.

The adhesive layer consists of a composition of 99 to 70 parts by weight of a modified polyolefin, preferably 97 to 80 parts by weight, and 1 to 30 parts by weight, preferably 3 to 20 parts by weight of a hydrocarbon elastomer (total 100 parts by weight).

If the amount of the hydrocarbon elastomer is less than 1 part by weight, no effect of improving adhesion will be observed, and if it is more than 30 parts by weight, there will be problems in film formability.

The adhesive layer is usually prepared as a film of about 10 to 100 microns by T-die molding or the like.

Although there is no problem with increasing the thickness of the film of the adhesive layer, it is not economically preferable.

The metal foil of the laminate includes metals such as aluminum, iron, copper, tin, and nickel, and metals containing one or more of these as main components.

Among these, aluminum is preferably used.

The metal foil has a thickness of about 0.01 to 0.5 mm and is prepared by degreasing.

The feature of the present invention is that by using an adhesive layer consisting of a specific amount of a polyolefin graft-modified with an unsaturated carboxylic acid or a derivative thereof and a hydrocarbon elastomer,
The purpose is to obtain a laminate with excellent adhesion between the metal foil and the polyolefin layer, and the effects of the present invention cannot be obtained only with graft-modified polyolefin or hydrocarbon elastomer, as shown in the Examples and Comparative Examples described later. It is clear from this.

Further, a small amount of an inorganic compound such as a lubricant or a filler may be added to the adhesive layer to improve adhesiveness.

Inorganic compounds include magnesium oxide, calcium oxide, aluminum oxide, titanium dioxide, magnesium sulfate, calcium sulfate, magnesium hydroxide, aluminum hydroxide, and the like.

The present invention is particularly useful when manufacturing laminates continuously, and the present invention will be described below with reference to the drawings in this case.

FIG. 1 is a side view of an example of an apparatus used to carry out the present invention.

The metal foils 1 and 1' are degreased in advance and then rolled into rolls 1 and 1.
2)'& 1st l 上・ゝノ 1? Gate,■
It is heated to about 120° C. to 300° C. in preheaters 6, 6' and supplied to the roll pair 5, 5'.

Alternatively, the metal foil may be prepared by painting the outer surface after degreasing.

The preformed thin film 2, 2' serving as the adhesive layer is fed to a pair of rolls 5, 5' and laminated onto a metal foil to form a two-layer laminate, heated if necessary by a heater 7, 7'. So 12
Lamination is performed by heating to about 0°C to 300°C.

In the apparatus shown in Figure 1, two-layer laminates are continuously and simultaneously formed, but the two-layer laminates are formed by laminating various types of adhesive layers on metal foils elsewhere, and then the molten polyethylene It may also be supplied onto the sheet 9.

In this case, heating by the heater 7,7' is not particularly required.

The molten polyolefin sheet is melt-extruded at a temperature above the melting point and below 280°C and fed between pressure rolls 10° and 10'.

Its thickness is usually between 11n11L and 6.

If the temperature of the molten polyolefin sheet is below the melting point, adhesion will not occur, and if it exceeds 280°C, the adhesiveness will actually decrease.

The pressure rolls 10 and 10' are set at room temperature to 300°C, and after pressing the two-layer laminate on both sides of the molten polyolefin sheet, multiple pairs of cooling rolls 11 and 11 are applied.
'Sent to.

As the laminate is cooled and moves between the rolls IL11', it is pressurized to 0.1 ky/- to 4 kg/-, and the completely crimped laminate is taken off by a take-off machine 13.
It is cut into products.

The apparatus shown in FIG. 1 employs a method in which the adhesive layer is pasted on the metal foil in advance, and this method is a particularly preferred example of the present invention because the molding conditions can be selected over a fairly wide range. It is also possible to simultaneously supply the foil and adhesive film onto the molten polyolefin sheet.

According to the present invention, a laminate can be obtained that has both improved initial adhesiveness and durable adhesiveness, and can be used for a long time under severe conditions.

Example 1 High density polyethylene (melt index 1.5, density 0.965) was grafted with 1.0% maleic anhydride (10 parts by weight) and medium density polyethylene (tart index 40, density 0.925) was grafted to 90 parts by weight A modified polyethylene consisting of parts by weight was prepared.

A composition consisting of 90 parts by weight of this modified polyethylene and 10 parts by weight of polyisobutylene (trade name Vistanex MML-80, manufactured by Esso, hereinafter abbreviated as PIB) was molded into a 50 μm T-die film at a resin temperature of 220°C, and an adhesive film was formed. And so.

High-density polyethylene core material (melt index 1.0)
A laminate was manufactured using the apparatus shown in FIG. 1 using an aluminum foil having a density of 0.957 and a melting point of 120'C) and a thickness of 0.2 mm as the metal foil.

However, the extrusion temperature of the molten polyethylene sheet 9 is 200°C,
Set temperature of pressure rolls 10 and 10' is 220°C, pressure of cooling rolls 11 and 11' is 0.1 ky/min or 4 kg.
/ffl.

The adhesive strength of the obtained laminate is AS'rM-D-*790
It was measured by method 3.

In addition, after leaving the laminate in an atmosphere at 100°C for 500 hours,
Adhesive strength was measured in the same manner as above.

The results are shown in Table 1.

Comparative Example 1 Comparative example 1 was carried out in the same manner as in Example 1, except that the composition of the adhesive film was the same as in Example 1, consisting only of the modified polyethylene.

Comparative Example 2 The composition of the adhesive film was 90 parts by weight of medium density polyethylene (melt index 40, density 0.925) and P
The same procedure as in Example 1 was carried out except that the composition consisted of parts by weight of IBIO.

Examples 2 to 3, Comparative Example 3 The same procedure as in Example 1 was carried out except that the extrusion temperature of the polyethylene core material was changed to the ** temperature shown in Table 2.

If the temperature of the polyethylene core material is below the melting point, the adhesiveness will be significantly reduced, and even if it exceeds 280°C, sufficient adhesiveness will not be obtained.

Example 4 Polypropylene (melt index 7.0, density 0.
A modified polypropylene was prepared consisting of 10 parts by weight of a modified product obtained by grafting 1.0% by weight of maleic anhydride onto 91) and 90 parts by weight of polypropylene (melt index 6.5, density 0.91).

A composition consisting of 90 parts by weight of this modified polypropylene and 10 parts by weight of polyisobutylene was mixed at a resin temperature of 220°C.
It was molded into a 0μ T-die film to obtain an adhesive film.

The core material is polypropylene (Tart index 1.5, density 0.91, melting point 165°C) and the metal foil has a thickness of 0.
．． A laminate was produced in the same manner as in Example 1 using 2 mm aluminum foil.

However, the extrusion temperature of the molten polypropylene sheet is 230℃,
Pressure rolls 10, 10' set temperature 220°C1 cooling roll 11, pressure 11' 0.1 to 4 kg/cyt
It was t.

The initial adhesive strength of the obtained laminate was 25 ky,/1 nc.
h, the adhesive strength after being left in an atmosphere of 100°C for 500 hours was 24 kg/1 nch.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an example of an apparatus for carrying out the method of the present invention. 1.1...Metal foil, 2,2'...Adhesive film, 3,3', 4,4'...Guide roll, 5,5'... ...Roll pair, 6,6'...
...Preheater, 7,7'... Heater, 8...
...Extruder, 9...Polyolefin sheet, 1
0, 10'...pressure roll, 11.11'.
......Cooling roll, 12...... Laminate, 13
・・・・・・Collection machine.

Claims (1)

[Claims] 1. In a method of manufacturing a laminate by laminating metal foil on both sides of a polyolefin layer, a polyolefin in which part or all of the polyolefin is unsaturated carbon is applied on both sides of a molten polyolefin sheet having a melting point above 280°C. The metal foil is treated with an adhesive layer interposed between 99 to 70 parts by weight of a modified polyolefin grafted with at least one type of heptamer selected from acids or derivatives thereof and 1 to 30 parts by weight of a hydrocarbon elastomer. A method for producing a laminate with good adhesiveness, which is characterized by bonding under pressure. 2 The polyolefin layer has a density of 0.910β/cc to 0.970 g/cc, a melt index (190'
C) The manufacturing method according to claim 1, characterized in that the polyethylene is 0.05 to 100% polyethylene. 3. The manufacturing method according to claim 1, wherein the modified polyolefin is a modified polyolefin modified with maleic anhydride. 4. The production method according to claim 1, wherein the grafting ratio of the unsaturated carboxylic acid or its derivative to the polyolefin is 10 to 4 to 3% by weight. 5. The manufacturing method according to claim 1, wherein the hydrocarbon elastomer is polyisobutylene or ethylene-propylene rubber. 6. The manufacturing method according to claim 1, wherein the metal foil is an aluminum foil with a thickness of 0.011 nrIL to 0.5 mm. 7. The manufacturing method according to claim 1, characterized in that metal foil on which adhesive layers have been laminated in advance is laminated on both sides of the molten polyolefin sheet. 8. The manufacturing method according to claims 1 to 7, wherein the metal foil is bonded using a pressure roll. 9. The manufacturing method according to claims 1 to 8, wherein the metal foils are bonded together under pressure and then cooled.