JPH0241236A - Laminated sheet - Google Patents

Abstract

PURPOSE:To provide a heat resistant foamed laminated sheet by providing nonfoamed films made of specific polyamide resin composition on one or both side faces of a foamable sheet made of specified heat resistant styrene resin. CONSTITUTION:A nonfoamable film layer 1 is made of a polyamide resin compo sition containing 30 - 55wt.% of heat resistant styrene resin and 70 - 45wt.% of polyamide resin. A foamed sheet made of heat resistant styrene resin for forming a foamed sheet layer 2 preferably contains 30 - 5wt.% of functional component for forming the heat resistant styrene resin, i.e., unsaturated fatty carboxylic acid, unsaturated fatty dicarboxylic acid anhydride or 6-membered ring acid anhydride and particularly 20 - 10wt.% in the heat resistant styrene resin. In order to obtain the laminated sheet, it is made directly thermally fusion-adhere to by hot rolls.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a heat-resistant foam laminate sheet used primarily for manufacturing food containers for microwave ovens, such as ramen noodle containers, trays, molded ceilings, and the like.

[Prior Art] Foamed laminated sheets used to manufacture conventional microwave food containers, etc. are generally made by combining a non-foamed film made of a crystalline resin such as a polyolefin resin or a polyester resin with a polyester resin. Since it is laminated onto a foamed sheet made of a non-quality resin, there is a problem in that the thermoformability is poor.

In addition, as mentioned above, conventional laminated sheets are made by laminating crystalline resin and non-standard resin that are poorly compatible with each other, so even if a non-standard product is produced, it can be reused (reworked). )
This also caused product costs to rise.

[Problem to be solved by the invention]

The purpose of the present invention is to provide an unprecedented laminated sheet that combines the following conditions (1) to (3): (1) When forming a laminated sheet, many non-standard products etc. The point is that the cost increases because it cannot be reused.

(2) In order to improve the oil resistance of food containers for microwave ovens, crystalline resins such as polyolefin resins and polyesters are used as non-foamed films, and it is difficult to form sheets laminated to foamed sheets.

(3) A laminated sheet has generally been made by laminating a non-foamed film on a foamed sheet via an adhesive layer.

[Means to solve the problem]

The present invention provides (A) (a) styrene compounds 70-95
(b) A copolymer consisting of 70-95% by weight of a styrene compound and 30-5% by weight of an unsaturated aliphatic dicarboxylic acid anhydride. Polymer; (c) a copolymer consisting of 70 to 95% by weight of a styrene compound and 30 to 5% by weight of an unsaturated aliphatic carboxylic acid, or
99 of a copolymer consisting of 70 to 95% by weight of a styrene compound and 30 to 5% by weight of an unsaturated aliphatic carboxylic anhydride.
~50 parts by weight of polymer of lower alkyl ester of unsaturated aliphatic monocarboxylic acid 1~50 parts by weight (R1 and R
(2 is the same or different hydrogen atom or alkyl group, respectively) 0.1 to 95% by weight of a six-membered cyclic acid anhydride; and (2) a polymer of lower alkyl ester of unsaturated aliphatic monocarboxylic acid. 1 to 95% by weight; (1) a copolymer consisting of 5 to 95% by weight of a styrenic compound; and (2) 0.5 to 30% by weight of an unsaturated aliphatic carboxylic acid; one or more heat-resistant styrenic resins selected from (B) (a) (<) A copolymer consisting of 70 to 95% by weight of a styrene compound and 30 to 5% by weight of an unsaturated aliphatic carboxylic acid; (0) Styrene Copolymer consisting of 70 to 95% by weight of a styrene compound and 30 to 5% by weight of an unsaturated aliphatic dicarboxylic acid anhydride; (c) 70 to 95% by weight of a styrene compound and 30 to 5% by weight of an unsaturated aliphatic carboxylic acid % or a copolymer consisting of 70 to 95% by weight of a styrenic compound and 30 to 5% by weight of an unsaturated aliphatic dicarboxylic anhydride.
~50 parts by weight and 1 to 50 parts by weight of a polymer of lower alkyl ester of unsaturated aliphatic monocarboxylic acid (R1 and R in the formula
0.1 to 95% by weight of a six-membered cyclic acid anhydride (z is - or a different hydrogen atom or alkyl group, respectively) and a polymer of a lower alkyl ester of an unsaturated aliphatic monocarboxylic acid. 1 to 95% by weight; (1) a copolymer consisting of 5 to 95% by weight of a styrenic compound; and (2) 0.5 to 30% by weight of an unsaturated aliphatic carboxylic acid; one or more heat-resistant styrenic resins selected from 30-5
Polyamide resin composition containing 5% by weight 2 and 70 to 45% by weight of polyamide resin: Based on 100 parts by weight of the polyamide resin compositions (b) and (a), a vinyl aromatic hydrocarbon and a conjugated diene compound are further added. A resin composition containing 0.5 to 30 parts by weight of a block copolymer and/or its hydrogenated product: Or, based on 100 parts by weight of the polyamide resin composition of (C) and (a)), Furthermore, 0.5 to 30 parts by weight of a modified block copolymer obtained by adding an unsaturated dicarboxylic acid or a derivative thereof to a block copolymer of a vinyl aromatic hydrocarbon and a conjugated diene compound and/or its hydrogenated product. The object of the present invention is to provide a heat-resistant foamed laminate sheet having a non-foamed film made of one type of resin composition selected from the following.

The present invention also includes the following embodiments; (1) The foamed sheet (A) and the styrene compound constituting the polyamide resin composition (A) of the non-foamed sheet (B) A copolymer consisting of an unsaturated aliphatic carboxylic acid or an unsaturated aliphatic dicarboxylic acid anhydride contains styrene 70-95
The laminate sheet according to the claims, which is a copolymer consisting of 30 to 5% by weight of methacrylic acid or maleic anhydride.

(2) The laminate sheet according to the claims, wherein the styrene compound is styrene, α-methylstyrene, or P-methylstyrene.

(3) A laminate sheet according to the claims, wherein the polyamide constituting the polyamide resin composition (a) is polycaprolactam.

(4) A laminate sheet according to the claims, wherein the polyamide is polyhexamethylene adipamide.

The present invention will be explained below based on the drawings.

FIGS. 1 and 2 are partial cross-sections showing the laminated sheet of the present invention.

In Figures 1 and 2, ■ is ■, (a) is a copolymer of styrene and methacrylic acid (hereinafter abbreviated as SM^A copolymer), and (b) is a copolymer of styrene and maleic anhydride. Polymer (hereinafter abbreviated as SMh copolymer), (c) SMAA
a copolymer or a mixture of a 5JIA copolymer and a polymer mainly composed of methyl methacrylate (hereinafter abbreviated as "polymer"), or (d) styrene, methyl methacrylate, methacrylic acid, and a six-membered cyclic acid anhydride. (Substituent R1, I?t:
A polyamide resin composition (A) consisting of any of the heat-resistant styrene resins (hereinafter abbreviated as MSMAi copolymers) with methyl groups); ■polycaprolactam; or (^
) of the polyamide resin composition, a) a styrene-butadiene block copolymer and (or) its hydrogenated product; or b) anhydrous maleic to the (hydrogenated) styrene-butadiene block copolymer. A non-foamed film layer made of any one of the resin composition (B) blended with a modified block copolymer to which an acid has been added is shown.

2 is a) SMAA copolymer; b) SMA copolymer;
c) SMAA copolymer or SMA copolymer and PMMA
d) a foamed sheet layer of a heat-resistant styrenic resin, either a mixture with a polymer, or d) an MSAA copolymer.

Specifically, the non-foamed film layer contains 30 to 55% by weight of the heat-resistant styrene resin and 70 to 45% by weight of the polyamide resin.
2, wherein the weight average molecular weights of the heat-resistant styrene resin and the polyamide are 5 to 500,000 and 1.5 to 10,000, respectively. It is a non-foamed film.

The styrene compounds used in the present invention include styrene,
α-methylstyrene, P-methylstyrene, etc. can be used alone or in combination; Further, unsaturated aliphatic carboxylic acids include methacrylic acid, acrylic acid, etc.; Also, unsaturated aliphatic dicarboxylic acid anhydrides For example, maleic anhydride is used.

In addition, examples of lower alkyl esters of unsaturated aliphatic monocarboxylic acids include methyl methacrylic acid or acrylic acid,
Esters such as ethyl, butyl, propyl and the like are preferred, especially methyl ester.

As the six-membered cyclic acid anhydride represented by the general formula, substituent R1
, R2 are all methyl groups.

The PMMA polymer is preferably a polymer containing methyl methacrylate as a main unit, particularly a copolymer of 90% by weight methyl methacrylate and 10% by weight methyl acrylate.

Suitable polyamides for use in the present invention include polycaprolactam (nylon-6) and polyhexamethylene adipamide (nylon-6,6).

Polyamide is in the sea state, SMAA copolymer or SMA
By creating a structure in which heat-resistant styrene resin such as a copolymer is microdispersed in the form of islands, it is possible to maintain the excellent durability that is characteristic of nylon, such as oil resistance and slipperiness, and also to have excellent mechanical properties. Toughness can be maintained.

In the polyamide resin composition of the present invention, 45 to 70% by weight of polyamide and S
It is necessary to blend the heat-resistant styrene resin such as MAA copolymer or SMA copolymer in a range of 55 to 30% by weight.

By using this blending ratio, molding stability can be improved and dimensional stability due to a decrease in hygroscopicity can be improved. The above-mentioned improvement effect is large in the range of 45 to 70% by weight of polyamide.

To microdisperse heat-resistant styrene resin such as SMAA copolymer or SMA copolymer in a sea of polyamide,
A composition ratio of 30 to 5% by weight of the functional component constituting the heat-resistant styrene resin, that is, unsaturated aliphatic carboxylic acid, unsaturated aliphatic dicarboxylic acid anhydride, or six-membered cyclic acid anhydride is possible. However, preferably the functional component 10-
20% is better. Further, if the proportion of the functional component in the heat-resistant styrene resin is less than 5% by weight, the compatibility with polyamide becomes poor, and phenomena such as peeling of molded products as a molding material are observed.

Generally, in the microdispersion of the heat-resistant styrenic resin in the polyamide resin composition of the present invention, heat-resistant styrenic resin particles of about 5 μm or less are in a stable and uniform state dispersed in a sea of polyamide.

Furthermore, if the proportion of the heat-resistant styrene resin exceeds 30% by weight, a gel-like substance is purified during production of the copolymer, making it difficult to increase the molecular weight.

SMAA copolymer, SMA copolymer or MS? The lAA copolymer has a weight average molecular weight of 50,000 to 500,00 in terms of styrenic compound polymer molecular weight measured using gel perfusion chromatography.
0, preferably in the range of 150,000 to 400,000.

In addition, as polyamide, polycaprolactam and polyhexamethylene adipamide have a weight average molecular weight of 15
,000-100,000 preferably 45,000-8
It is desirable to use a value in the range of 0,000.

Next, the rubber component additionally blended into the polyamide resin composition constituting the non-foamed film layer will be described in detail below.

Vinyl aromatic hydrocarbon-conjugated diene block copolymer or its hydrogenated product and modified block copolymer in which unsaturated dicarboxylic acid or its derivative is added to vinyl aromatic hydrocarbon-conjugated diene block copolymer or its hydrogenated product The combination is: ■ A block copolymer having at least one vinyl aromatic compound copolymer block A and at least one conjugated diene block copolymer block B (this is called [base block copolymer F]) a modified block copolymer in which a molecular unit containing a dicarboxylic acid group or a derivative group thereof is bonded to A block copolymer having a polymer block B'' (block B is an olefin compound polymer block with an unsaturation degree not exceeding 20%) (this is referred to as ``basic block copolymer H'') It is a modified block copolymer in which a molecular unit having a dicarboxylic acid group or a derivative group thereof is bonded to.

"Basic block copolymer F" contains at least one, preferably two or more, vinyl aromatic compound polymer block A and at least one copolymer block B mainly composed of conjugated diene. It is something. Here, the polymer block B mainly composed of conjugated diene means that the weight ratio of the vinyl aromatic compound and the conjugated diene compound is O/100 to 5.
0150, preferably a polymer block consisting of a composition range of 0/100 to 20/70, and the distribution of the vinyl aromatic compound in this block is random, tapered (in which the monomer component increases or decreases along the molecular chain). ), partially block-shaped, or any combination thereof.

In addition, in the present invention, "basic block copolymer F"
'', the vinyl aromatic compound is added to the transition region between the vinyl aromatic compound polymer block A and the polymer block B mainly composed of a conjugated diene compound (i.e., the transition region from block 8 to the block B boundary region). The content of
Although a copolymer block of a vinyl aromatic compound and a conjugated diene compound may exist in an amount exceeding % by weight, such a polymer block is included in the above-mentioned polymer block mainly composed of a conjugated diene compound.

In the "basic block copolymer F", the weight ratio of the content of the vinyl aromatic compound and the content of the conjugated diene compound is preferably in the range of 1'O/90 to 90/lo.
The range of 5/85 to 85/15 is more preferable.

Such a block copolymer exhibits properties as a thermoplastic elastomer when the content of the vinyl aromatic compound is about 60% by weight or less, preferably 55% by weight or less, and the "basic block copolymer" It is suitably used as "Polymer F".

Vinyl aromatic compounds constituting the "basic block copolymer F" include styrene, α-methylstyrene,
One or more types are selected from vinyltoluene and the like, and styrene is particularly preferred. The conjugated diene compound is selected from one or more of butadiene, isoprene, 1,3-pentadiene, etc., and butadiene and/or isoprene are particularly preferred.

The above block copolymer has a number average molecular weight of 20,000
- soo, ooo, and the molecular weight distribution (ratio of weight average molecular weight to number average molecular weight) is preferably in the range of 1.05 to 10. Further, the molecular structure of the block copolymer may be linear, branched, radial, or a combination thereof. Furthermore, when butadiene is used as a conjugated diene compound in a block copolymer, the amount of 1.2 bonds in the microstructure of the microportion of the butadiene portion is 5 to 5.
A range of 80% is preferred.

When the block copolymer contains two or more vinyl aromatic compound polymer blocks A or polymer blocks B mainly composed of a conjugated diene compound, each block may have the same structure, Each structure such as monomer component content, distribution in their molecular chains, block molecular weight, microstructure, etc. may be different.

As a method for producing the "basic block copolymer F", for example, Japanese Patent Publication No. 36-19286, Japanese Patent Publication No. 43-1986,
Examples include methods described in Japanese Patent Publication No. 14979, Japanese Patent Publication No. 49-36957, Japanese Patent Publication No. 4B-2423, Japanese Patent Publication No. 4B-4106. In all of these, an organic lithium compound or the like is used as an anionic polymerization initiator in a hydrocarbon solvent, and if necessary, an ether compound such as diethyl ether or tetrahydrofuran is used as a vinylizing agent; triethylamine, N, N.

Tertiary amines such as N',N'-tetramethylethylenediamine; Lewis bases such as phosphine compounds such as hexamethylphosphoamide; polyfunctional compounds such as silicon tetrachloride and epoxidized soybean oil as coupling agents; This is a method in which a vinyl aromatic compound and a conjugated diene compound are copolymerized. The block copolymers obtained by these methods have a linear, branched or radial structure.

In the present invention, any polymer obtained by any polymerization method can be used as long as it is within the above range. Furthermore, it is also possible to use not only one type of block copolymer but also a mixture of two or more types.

The olefin compound polymer block B° of the “basic block copolymer H” refers to ethylene, propylene, 1-
Monoolefins such as butene and isobutylene; or conjugated diolefins such as butadiene, isoprene and l+3-pentadiene: l,4-hexadiene, norbornene,
A polymer block having a polymerized or copolymerized form of one or more olefin compounds selected from non-conjugated diolefins such as norbornene derivatives, and
The degree of unsaturation of the block is less than 20%. Therefore, when the above diolefins are used as constituent monomers of an olefin compound polymer block, the degree of unsaturation is reduced by a method such as hydrogenation to an extent that the degree of unsaturation in the block portion does not exceed 20%. In addition, vinyl aromatic compounds may be randomly copolymerized in the olefin compound polymer block B°.
" Examples include hydrogenated block copolymers of a vinyl aromatic compound and a conjugated diene compound, block copolymers of a vinyl aromatic compound and a monoolefin, and the like.

In the present invention, a particularly preferable basic block copolymer H is selected such that the degree of unsaturation in the conjugated diene moiety of the basic block copolymer F does not exceed 20%. In such a case, if the modified block copolymer is required to have rubber elasticity, the amount of 1.2 bonds is 25
It is recommended to use a block copolymer in the range of ~65%, preferably 35-55%, as the polymer before hydrogenation.

"Basic block copolymer H" can also be obtained by hydrogenating the above-mentioned "basic block copolymer F" by a known method, for example, the method described in Japanese Patent Publication No. 42-8704. A basic block copolymer H" is obtained. ``The basic block copolymer HJ is ``at least 80% of the aliphatic double bonds based on the conjugated diene compound in the polymer block mainly composed of the conjugated diene compound of the basic block copolymer FJ. In other words, the degree of unsaturation in the block morphologically converted into the olefin compound polymer block B'' by hydrogenation of the polymer block B mainly composed of a conjugated diene compound does not exceed 20%. It is preferable.

When a block copolymer in which the degree of unsaturation of the olefin compound polymer block does not exceed 20% is used as the "basic block copolymer H", a composition suitable for applications requiring weather resistance and heat aging resistance. You can get things.

On the other hand, the hydrogen of the aromatic double bond based on the vinyl aromatic compound copolymerized in the vinyl aromatic compound of the vinyl aromatic compound polymer block portion and, if necessary, the polymer block mainly composed of a conjugated diene compound. Although there is no particular restriction on the addition rate, it is preferable that the hydrogenation rate is 20% or less.

The degree of unsaturation of the olefin compound polymer block B'' can be measured by instrumental analysis using an infrared spectrophotometer (IR), nuclear magnetic resonance (NMR), etc., titration analysis using iodometry, etc.

The "basic block copolymer F or H" is then modified by an addition reaction with an unsaturated dicarboxylic acid or a derivative thereof to synthesize the modified block copolymer used in the present invention.

Examples of unsaturated dicarboxylic acids or derivatives thereof include maleic acid, fumaric acid, itaconic acid, halogenated maleic acid, cis-4-cyclohexene-1,2 dicarboxylic acid,
Examples include endo-cis-bicyclo(2,2゜l)-5-heptene-2,3-dicarboxylic acid, and derivatives of these dicarboxylic acids, such as acid anhydrides, esters, amides, and imides. Not only seeds but also a mixture of two or more types can be used.

Among these, maleic anhydride is particularly preferred. These unsaturated dicarboxylic acids are preferable because they have higher reactivity than monocarboxylic acids and can easily yield a uniform modified block copolymer with a high addition rate.

A modified block copolymer is produced by adding an unsaturated dicarboxylic acid or a derivative thereof to the "basic block copolymer F or H" in a solution or melt state with or without the use of a radical initiator. obtained by. The method for producing these modified block copolymers is not particularly limited in the present invention, but the modified block copolymers obtained may contain undesirable components such as gel, or their melt viscosity may significantly increase, leading to processing. A manufacturing method that deteriorates properties is not preferred. A preferred method is to prepare the basic block copolymer F or H, for example in an extruder, in the presence or absence of a radical initiator.
and an unsaturated dicarboxylic acid or a derivative thereof.

The amount of molecular units containing a dicarboxylic acid group or its derivative group contained in the modified block copolymer, that is, the amount of unsaturated dicarboxylic acid or its derivative added, is 100% of the vinyl aromatic hydrocarbon-conjugated diene block copolymer. The amount added is in an average range of 0.05 to 20 parts by weight per part by weight, and if the amount added is less than 0.05 parts by weight, the properties of the resin composition of the present invention will be lost.

In particular, the above conditions are necessary to obtain uniformity of the resin composition of the present invention or uniform mechanical strength, impact resistance, surface adhesion, and paintability of the polymer composition.

The content of molecular units containing a dicarboxylic acid group or its derivative group in the modified block copolymer can be easily determined by a method using an infrared spectrophotometer, titration, or the like.

In addition, in the present invention, even if unmodified block copolymers are included, as long as the amount of unsaturated dicarboxylic acid or its derivative added in the modified block copolymer satisfies the above range as an overall average value, good.

In the method for producing a modified block copolymer as described above,
Although unreacted unsaturated dicarboxylic acids or derivatives thereof generally remain in the modified block copolymer, this unreacted material may be completely removed or may be left as is.

Next, as a foamed sheet made of a heat-resistant styrene resin forming the foamed sheet layer 2, functional components constituting the heat-resistant styrenic resin, namely unsaturated aliphatic carboxylic acid,
A foamed sheet containing an unsaturated aliphatic dicarboxylic acid anhydride or a six-membered cyclic acid anhydride in a proportion of 30 to 5% by weight, particularly 20 to 10% by weight, in a heat-resistant styrenic resin is preferred. If the proportion of the functional component is less than 5% by weight, the heat resistance of the microwaveable food container made of the laminated sheet will be poor, which is not preferable. Moreover, if the functional component is 30% by weight or more, moldability deteriorates, which is not preferable.

In the laminated sheet of the present invention, the above-mentioned non-foamed film 1
The thickness is preferably 10 to 500 μm. Furthermore, it is preferably 40 to 120 μm. If the thickness of the non-foamed film 1 is less than 10 μm, the foam layer will be visible when used as a food container for a microwave oven, which is unfavorable in terms of appearance. In addition, the thickness of the non-foamed film l is 500 μm.
If it exceeds m, when laminated with a foam sheet to form a laminated sheet, it may result in uneven molding, which is undesirable, and the cost will increase, which is undesirable.

The thickness of the heat-resistant styrene resin foam sheet 2 is 0.2 to 15
+*/+s is preferred. If the heat-resistant styrene resin foam sheet 2 is too thin (less than 0.2 m/+), the rigidity of the container etc. will be reduced, making handling inconvenient.

The thickness of the heat-resistant styrene resin foam sheet 2 is 158/
If it exceeds -, the performance of the foam sheet is good, but the cost increases unnecessarily and is not practical.

In the laminated sheet of the present invention, the heat-resistant styrene resin foam sheet 2 can be produced by a foaming technique such as so-called extrusion foaming using a heat-resistant styrenic resin mixed with a foaming agent using a molding method such as an inflation method or a T-die method. As the blowing agent to be used, decomposition type blowing agents such as azodicarboxylic acid amide, azobisisobutyronitrile, diazoaminobenzene, etc., or physical type (evaporation type) blowing agents such as butane, pentane, freon, trichloroethylene, etc. can be used. However, physical blowing agents are preferred.

The foamed sheet 2 preferably has an expansion ratio of 4 to 20 times. If the foaming ratio is less than 4 times, the foaming ratio of the obtained foam sheet tends to be low, which tends to cause problems with heat retention, which is undesirable.If the foaming ratio exceeds 20 times, the foam sheet obtained The foaming ratio becomes too high,
This is not preferable because it becomes inferior in toughness.

In order to produce a laminated sheet from the non-foamed film 1 and the foamed film 2 of the present invention, any known laminating means can be applied, but a lamination method in which direct heat welding is performed using a hot roll or the like is preferred. Of course, an adhesive lamination method using an adhesive such as an ethylene-vinyl alcohol copolymer may also be used alone or in combination with other lamination means.

When manufacturing food containers for microwave ovens and the like from the laminated sheet of the present invention, sheet forming can be applied by any convenient technical means such as vacuum forming, pressure forming, pine molding, etc. In particular, when the non-foamed film 1 is used as the inner layer of the container, it is possible to obtain a container with excellent oil resistance.

The laminated sheet of the present invention is also useful when applied to molded ceilings of automobiles, etc.

〔Evaluation item〕

(1) Possibility of reuse (rework); Retention rate of mechanical strength (tensile strength) of reworked non-foamed film of 70% or more ・・・・・・○ Same as above 70-4
Retention rate of 0χ・・・・・・△Same as above Retention rate of 40% or less・・・・・・×(2) Formability of laminated sheet; 3rd
In a deep-drawn product (W/H=1/l) as shown in the figure; Good forming of the deep-drawn container...O Tears or kinks occur when forming the deep-drawn container.
・・・・・・・・・・・・× (3) Appearance of the sheet No gui lines on the sheet surface... O gui lines appear on the sheet surface...× (4) Oil resistance Add salad oil to the container shown in Figure 3. 100 for 30 minutes.
``Crank does not occur on the inner surface of the container when held at 120°C...O Same as above.Crank occurs...×(5) No deformation after 30 minutes of heat-resistant container at 120°C...・◎No deformation after 30 minutes at 100°C...○Container at 100°C
Deformation occurred after 30 minutes at °C...Examples 1 to 12 and Comparative Examples 1 to 7 are summarized in Tables 1 and 2.

The abbreviations for each component used in Examples and Comparative Examples indicate the following.

SMAA (copolymer); styrene-methacrylic acid copolymer SMA (copolymer); styrene-maleic anhydride copolymer SAN (copolymer); styrene-acrylonitrile copolymer SBR, styrene-butadiene block Copolymer MAH, maleic anhydride MAA, methacrylic acid MSMAA (copolymer): Styrene-methyl methacrylate-methacrylic acid-6-membered cyclic acid anhydride copolymer PMMA (polymer): Delbet ■-8ON manufactured by Asahi Kasei ■
N-6; Nylon 6 (polycaprolactam) N-6,6
, Nylon 66 (Polyhexamethylene adipamide) Next, in Tables 1 and 2, the relationship between Examples and Comparative Examples will be explained.

(2) Example 1 is the basic example, and Comparative Example 1 corresponds thereto.

When SMAA is used, it is shown to be compatible with polyamide (Example 1), but when SAN is used, it is incompatible with polyamide and shows poor results (Comparative Example 1).

■Examples 2 to 6 are examples in which specific rubbers were added to Example 1. Correspondingly, in Comparative Example 5, old PS8 (high impact polystyrene resin) was added. Therefore, it shows inferior results.

■In Examples 7 to 9, SM^A/PMM was used instead of SMAA in Example 1 in the non-foamed film resin composition.
Blend of AN (Example 7), M AA (Example 8),
An example using SMAA (Example 9) will be described, and a corresponding comparative example is Comparative Example 1.

■ In Example 10, similar results were obtained even if the heat-resistant styrene resin used for the non-foamed film (in this case, SM^^) and the heat-resistant styrene resin used for the foam sheet (in this case, SM^) were different. This indicates that the

(2) Example 11 describes an example in which nylon 6 is replaced with nylon 6.6, and similar results are obtained.

(2) Example 12 is an example in which an adhesive was also used when manufacturing the laminated sheet.

■Comparative Example 2 is an example in which the S-static copolymer composition ratio of the heat-resistant styrene resin is S t/MA^, 98/2, and the MAA content is small, reducing heat resistance and compatibility with polyamide. show.

■Comparative Examples 3 and 4 are based on the resin composition ratio of the non-foamed film, SM
^^ Bar 6 shows an example outside the scope of the present invention.

■Comparative Examples 6 and 7 are resin composition ratio of non-foamed film; SM
An example in which A/N-6 is outside the scope of the present invention is shown.

(Effects of the Invention) The laminated sheet of the invention is useful as a molding material for food containers for microwave ovens, such as ramen noodles containers, trays, and molded ceilings.

In addition, the combination of the resin composition for non-foamed film and the resin composition for foamed sheet that constitutes this laminated sheet is new, and non-standard products when molding non-foamed film, foamed sheet and laminated sheet are free. Since it can be reused in foamed films, etc., there is less loss of the resin material (laminated sheet) used, and the cost of the product can be reduced.

Furthermore, polyamide resin compositions in which SMAA copolymer, SMA copolymer, etc. are blended with polyamide have better moldability for laminated sheets than crystalline resins such as polyolefin resins and PET resins disclosed in the prior art. The process is good, and there is little re-loss during film production, resulting in lower costs.

Additionally, SMAA copolymers or SMA copolymers have higher heat resistance than prior art polystyrene resins.

Further, the non-foamed film has excellent mechanical toughness and oil resistance because the polyamide is the base material in a polymer blend of a polyamide resin and an SMAA copolymer or an SMA copolymer.

[Brief explanation of the drawing]

FIGS. 1 and 2 are partial cross-sectional views showing the laminated sheet of the present invention. FIG. 3 shows a microwave oven container formed from the laminated sheet of the present invention. 1: Non-foamed film layer 2: Foamed sheet layer procedural amendment form

Claims (1)

[Scope of Claims] (A) (i) A copolymer consisting of 70 to 95% by weight of a styrene compound and 30 to 5% by weight of an unsaturated aliphatic carboxylic acid; (b) 70 to 95% by weight of a styrene compound and 30 to 5% by weight of an unsaturated aliphatic dicarboxylic acid anhydride; (c) A copolymer consisting of 70 to 95% by weight of a styrene compound and 30 to 5% by weight of an unsaturated aliphatic carboxylic acid. Or
9 of a copolymer consisting of 70 to 95% by weight of a styrene compound and 30 to 5% by weight of an unsaturated aliphatic dicarboxylic anhydride.
A mixture of 9 to 50 parts by weight and 1 to 50 parts by weight of a polymer of lower alkyl ester of unsaturated aliphatic monocarboxylic acid; or (d) [1] General formula ▲ Numerical formula, chemical formula, table, etc. ▼ ( 0.1 to 95% by weight of a six-membered cyclic acid anhydride represented by (where R^1 and R^2 are the same or different hydrogen atoms or alkyl groups, respectively); and [2] unsaturated aliphatic A copolymer consisting of 1 to 95% by weight of a polymer of lower alkyl ester of monocarboxylic acid, [3] 5 to 95% by weight of a styrene compound, and [4] 0.5 to 30% by weight of an unsaturated aliphatic carboxylic acid. Coalescence; (B) (a) (a) 70 to 95% by weight of a styrene compound on one or both sides of a foamed sheet made of one or more heat-resistant styrenic resins selected from
and 30 to 5% by weight of an unsaturated aliphatic carboxylic acid; (b) A copolymer consisting of 70 to 95% by weight of a styrene compound and 30 to 5% by weight of an unsaturated aliphatic dicarboxylic acid anhydride. (c) a copolymer consisting of 70 to 95% by weight of a styrene compound and 30 to 5% by weight of an unsaturated aliphatic carboxylic acid, or;
9 of a copolymer consisting of 70 to 95% by weight of a styrene compound and 30 to 5% by weight of an unsaturated aliphatic dicarboxylic anhydride.
A mixture of 9 to 50 parts by weight and 1 to 50 parts by weight of a polymer of lower alkyl ester of unsaturated aliphatic monocarboxylic acid; or (d) [1] General formula ▲ Numerical formula, chemical formula, table, etc. ▼ ( 0.1 to 95% by weight of a six-membered cyclic acid anhydride represented by (where R^1 and R^2 are the same or different hydrogen atoms or alkyl groups, respectively); and [2] unsaturated aliphatic A copolymer consisting of 1 to 95% by weight of a polymer of lower alkyl ester of monocarboxylic acid, [3] 5 to 95% by weight of a styrene compound, and [4] 0.5 to 30% by weight of an unsaturated aliphatic carboxylic acid. Combination; one or more heat-resistant styrene resins selected from 30 to 5
A polyamide resin composition containing 5% by weight and 70 to 45% by weight of a polyamide resin; based on 100 parts by weight of the polyamide resin compositions (b) and (a), a vinyl aromatic hydrocarbon and a conjugated diene compound are further added. A resin composition containing 0.5 to 30 parts by weight of a block copolymer and/or its hydrogenated product; or, based on 100 parts by weight of the polyamide resin composition of (c) and (a), further 0.5 to 30 parts by weight of a modified block copolymer obtained by adding an unsaturated dicarboxylic acid or a derivative thereof to a block copolymer of a vinyl aromatic hydrocarbon and a conjugated diene compound and/or its hydrogenated product. A heat-resistant foam laminate sheet having a non-foamed film made of one type of resin composition selected from the following.