JPS61242820A - Laminating method - Google Patents

Abstract

PURPOSE:To enable to be superior in laminating properties such as stretchability, neck-in and extrusion irregularity and to improve also surface states such as gloss irregularity and smoothness of an obtained thing, by laminating to a base material by making a resin composite into a base material side by performing co-extrusion of the specific resin composite and polypropylene homopolymer whose melt-flow rate is specific. CONSTITUTION:Co-extrusion of a resin composite composed of 60-95wt% polypropylene whose melt-flow rate is 5-100g/10min and 50-40wt% polyethylene having long-chain ramification whose melt-flow rate is 0.2-40g/10min and polypropylene homopolymer whose melt-flow rate is 1-100g/10min are performed and a base material is laminated by making the foregoing resin composite into a base material side. As the resin composite is made into the base material side by performing co-extrusion of the resin composite and the polypropylene homopolymer like this, elimination of extrusion irregularity is brought about by the resin composite and an excellent surface state wherein heat resistance, glass irregularity and surface roughness are not seen is made to bring about by the polypropylene homopolymer.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a laminating method that provides a laminate having a polypropylene layer with excellent surface condition.

(Prior art) Conventional polypropylene laminates include light packaging materials based on biaxially oriented polypropylene film, engineering paper based on paper, sheets based on cloth made of I-lipropylene tape, etc. It is often used in

Although polypropylene has excellent heat resistance, it is extruded at a high temperature at which it can be laminated, resulting in severe extrusion unevenness.To solve this problem, I-lipropylene laminated grate generally has long chain branches. i? IJ ethylene is a mixture of so-called high-pressure low-density polyethylene. However, the surface of the laminate exhibits uneven gloss and roughness due to the poor compatibility between the two, and a solution to the surface condition is desired, especially in the case of processing paper used in the production of synthetic leather.

(Problems to be Solved) The object of the present invention is to provide a laminate made of polypropylene. The objective is to improve the surface condition of the IJ propylene layer, which shows uneven gloss and rough skin.

(Means for solving the problems) The gist of the present invention is that the melt flow rate is 5 to 100, li'
/10min polypropylene 60-95% by weight and melt flow rate) 0.2-40,! 9/ICmin
A resin composition consisting of polyethylene having a long chain branch of 5 to 40% by weight and a melt flow rate of 1 to 100.9/1
By coextruding 0 min polyzolopyrene homopolymer,
O is a laminating method characterized in that the resin composition is laminated onto a substrate with the resin composition on the substrate side. (Specific explanation of means) The polypropylene in the present invention has a melt flow rate (
JISK6758) 5 to 100g/10min,
If it is less than 5N/10min, the spreadability is insufficient and 100#/1
If it exceeds 0 min, the neck-in will be severe. PoIJ-r
-Tyrene has a melt flow rate (JISK6730) 0
．． 1 to 40 g/10 min, which is also a melt flow rate) 0.2,! If it is less than i'/10 min, the spreadability is insufficient, and if it exceeds 40 N/10 min, neck-in is severe.

In order to provide heat resistance due to polypropylene and elimination of extrusion unevenness due to polyethylene, the weight ratio of polypropylene is 60 to 95 and the weight ratio of 4-reproduced ethylene is 5 to 40.

Note that the polyglopylene/I-lipropylene random copolymer or polypropylene block copolymer may be used, but polyzolopylene homopolymer is preferable from the viewpoint of heat resistance. Also, polyethylene has a density of 0.915 to 0.930 g
Polyethylene having long chain branches at /Cr, so-called high-pressure process low density polyethylene, and polyethylene having short chain branches so-called linear high- and low-density polyethylene, extrusion unevenness is severe.

On the other hand, the polypropylene homopolymer coextruded with the resin composition has a melt flow rate of 1 to 100,100 g, 7 l.
0, 1, I? If it is less than /10 min, the spreadability will be insufficient, and if it exceeds 1001710 min, extrusion unevenness will be severe. In addition, polypropylene random copoly? -,)i
e-lipropylene block co? Rimmer lacks heat resistance.

In the present invention, by coextruding a resin composition and a polypropylene homopolymer and using the resin composition as the base material side, extrusion unevenness is eliminated because of the resin composition, and heat resistance is achieved because of the polypropylene homopolymer. Also, an excellent surface condition with no uneven gloss or rough skin can be achieved.

Co-extrusion can be carried out using a regular T-die type device.
It may be bonded externally, but it may also be bonded before the die, that is, at the joint between the extruder and the die. In addition, the base material is a biaxially stretched polyzolopyrene film.

Examples include paper, cloth made of polypropylene tape, etc., and the lamination method of the present invention is suitably used for manufacturing process paper that requires heat resistance and a smooth surface condition.

(Example, Comparative Example) In a coextrusion laminate, 17811/m2 high-quality paper was used as a base material, and on the base material side (on the first extruder side of the coextruder) polypropylene shown in Table 1 and a low-carbon material having long chain branches were used. Using a resin composition made of density polyethylene, the second coextruder
Using a polypropylene homopolymer in an extruder, it was coextruded by adhering it at the joint between the extruder and the die, laminated on a base material, and taken off at a speed of 100 m/min.
81/m2 woodfree paper/15μ thick resin composition layer/15μ thick polyglobylene homopolymer single layer laminate or the above woodfree paper/
An attempt was made to manufacture a laminate with a single layer of resin having a thickness of 30 μm. Table 1 shows the lamination properties and the surface condition of the obtained laminate. Spreadability refers to whether the lamination is uniform or not, and neck-in refers to the degree to which the laminated parts are constricted inward. and
Extrusion unevenness is the extent to which extrusion is uniformly continuous.
The surface condition of the laminate was also observed with the naked eye, including gloss unevenness and smoothness.

In the table, Resin Al; polyzorogylene homopolymer〃 A2; Polypropylene random polymer // BlS Low density polyethylene with long chain branching MFR; Melt flow rate ◎; Very good O; Good Δ; Slightly poor X; Poor - ; Poor visual observation. The coextrusion conditions for polypropylene, a resin composition of low-density polyethylene having long chain branches, and polypropylene homopolymer are as follows.

Coextrusion, first extruder (base material side) Extruder; 90fiφ L/D=29 T die; 750m width T die temperature; 320°C Extrusion amount; 5
0yu/H coextrusion, second extruder extruder; 90maφ L/D=29T die; 750
■Width T-die temperature; 300°C extruder; 50 Yu/H As is clear from Table 1, according to the method of the present invention, the lamination properties and surface condition are very good or good, but the resin composition The surface condition of the single layer was slightly poor (Comparative Example 1), and the single layer of polypropylene homopolymer (Comparative Example 2)
, the resin composition of propylene is low melt (Comparative Example 3)
), the polypropylene of the resin composition is a high melt (Comparative Example 4), and the low density polyethylene of the resin composition is a low melt (
Comparative Example 5], when the low-density polyethylene of the resin composition is high melt (Comparative Example 6) and when the composition ratio of the resin composition is different from that of the present invention (Comparative Examples 7 and 8), before and after the melt extrudate touches the base material, It broke. Furthermore, when the polypropylene homopolymer is low melted, the surface condition is somewhat poor (Comparative Example 9).

(Effects) As described above, according to the laminating method of the present invention, 1.
It has excellent lamination properties such as spreadability, neck-in, and extrusion unevenness, and the surface condition of the obtained laminate, such as gloss unevenness and smoothness, is also improved.

Claims (1)

[Claims] 60-95% by weight of polypropylene with a melt flow rate of 5-100 g/10 min and a melt flow rate of 0.
A resin composition consisting of 5 to 40% by weight of polyethylene having long chain branching of 2 to 40 g/10 min and a polypropylene homopolymer with a melt flow rate of 1 to 100 g/10 min are coextruded, and the resin composition is used as a base material. A laminating method characterized by laminating wood.