JP2019043049A - Resin laminate foam plate, and thermoformed article and assembly box of the same - Google Patents

Abstract

To provide a resin laminate foam plate which is excellent in thermoformability and appearance designability and in strength, and to provide a thermoformed article and an assembly box of the same.SOLUTION: A resin laminate foam plate includes a foam resin layer 10, a non-foam resin layer 20 and a non-foam resin layer 22 provided on both surface of the foam resin layer, and a non-foam resin layer 30 provided on at least one non-foam resin layer 20. The foam resin layer 10 has a closed cell ratio of 70% or more and a thickness t10 of 2.0-6.0 mm, and does not substantially contain an inorganic filler. The non-foam resin layer 20 contains 5-40 mass% of the inorganic filler based on the total mass of the non-foam resin layer 20. A melting point of a resin of the non-foam resin layer 30 is lower than a melting point of a resin of the foam resin layer 10 and is lower than a melting point of a resin of the non-foam resin layer 20 adjacent to the non-foam resin layer 30, and the non-foam resin layer 30 has a surface glossiness of 60% or more and a thickness t30 of 0.02-0.10 mm.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a resin-laminated foam board, a thermoformed article thereof and an assembly box.

  Expanded polystyrene is lightweight and has excellent impact resistance. Therefore, it is widely used as a box material for transporting products and parts. However, expanded polystyrene is poor in oil resistance and is unsuitable as a material of a box for transporting machine products and machine parts to which oil is attached.

  With respect to such a problem, Patent Document 1 proposes a laminated sheet having a foamed layer of a polypropylene-based resin. According to this invention, the oil resistance of the packaging container which thermoformed the lamination sheet is improved.

Patent No. 4991345 gazette

However, the packaging container of Patent Document 1 is insufficient in thermoforming properties and surface smoothness (appearance design properties) when thermoforming a laminated sheet.
In addition, the packaging container of Patent Document 1 is intended for food use, and the strength is insufficient as a box for carrying heavier machine products and machine parts.
Therefore, the present invention is directed to a resin-laminated foam board which is excellent in thermoformability and appearance designability and is more excellent in strength, and a thermoformed article and an assembly box thereof.

In order to solve the above-mentioned subject, the present invention provides the following means.
[1] A foamed resin layer (A) of a polypropylene-based resin, a non-foamed resin layer (B) of a polypropylene-based resin provided on both sides thereof, and at least one of the non-foamed resin layers (B) It is a resin laminated foam board provided with the non-foaming resin layer (C) of polyolefin resin or polyester resin,
The foamed resin layer (A) has a closed cell ratio of 70% or more, a thickness of 2.0 to 6.0 mm, and substantially does not contain an inorganic filler,
The non-foamed resin layer (B) contains 5 to 40% by mass of the inorganic filler based on the total mass of the non-foamed resin layer (B),
The melting point of the resin of the non-foamed resin layer (C) is lower than the melting point of the resin of the foamed resin layer (A), and the non-foamed resin layer (B) adjacent to the non-foamed resin layer (C) Lower than the melting point of the
The non-foamed resin layer (C) has a surface gloss of 60% or more and a thickness of 0.02 to 0.10 mm.
[2] The melt mass flow rate (MFR) at 230 ° C. and 0.23 MPa of the resin of the foamed resin layer (A) and the resin of the non-foamed resin layer (B) is 5.0 g / 10 min or less, [1] The resin laminated foam board as described in.
[3] The foam resin layer (A) has a density of 100 to 700 kg / m ³ , and the foam cell layer (A) has an average cell diameter of 20 to 200 μm, according to [1] or [2] Resin laminated foam board.
[4] A thermoformed article obtained by thermoforming the resin-laminated foam board according to any one of [1] to [3].
[5] An assembly box having the thermoformed article according to [4] as a bottom plate and the resin-laminated foam board according to any one of [1] to [3] as a side plate.

  ADVANTAGE OF THE INVENTION According to the resin-laminated foam board of this invention, it is excellent in thermoforming property and appearance designability, and is excellent in intensity | strength.

It is sectional drawing of the resin lamination | stacking foam board which concerns on one Embodiment of this invention. It is a perspective view of the assembly box which concerns on one Embodiment of this invention. It is the III-III sectional view taken on the line of FIG.

The resin-laminated foam board (hereinafter, also referred to as a foam board) of the present invention is a foamed resin layer (A) of a polypropylene resin (hereinafter, also referred to as an A layer) and a nonfoamed resin layer (B) of a polypropylene resin (B) Hereinafter, the non-foamed resin layer (C) (hereinafter, also referred to as a C layer) of a polyolefin resin or a polyester resin is provided. In the present specification, in particular, the C layer is also referred to as a surface resin layer.
Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a cross-sectional view of a resin-laminated foam plate according to an embodiment of the present invention. In the foam board 1 of FIG. 1, the first B layer 20 is laminated on one side of the A layer 10, and the first C layer 30 is laminated on the first B layer 20. In the foam board 1, the second B layer 22 is laminated on the other surface of the A layer 10, and the second C layer 32 is laminated on the second B layer 22. The first C layer 30 and the second C layer 32 are located on the surface of the foam plate 1. That is, the first C layer 30 and the second C layer 32 are surface resin layers of the foam plate 1.
The A layer 10 and the first B layer 20 are thermally fused. The A layer 10 and the second B layer 22 are thermally fused. The first B layer 20 and the first C layer 30 are heat-sealed via a first adhesive layer (not shown). The second B layer 22 and the second C layer 32 are heat-sealed via a first adhesive layer (not shown).

The A layer 10 is a foamed resin layer of polypropylene resin. The foam board 1 is excellent in impact resistance by providing the A layer 10.
As a polypropylene resin which comprises A layer 10, the homopolymer (propylene polypropylene resin) of a propylene, a copolymer with another monomer, or these mixtures etc. are mentioned.
The polypropylene-based resin preferably contains 50% by mass or more, more preferably 70% by mass or more, and more preferably 80% by mass or more based on the total constituent units of the polypropylene-based resin. It is more preferable that Moreover, 100 mass% may be sufficient.

As said other monomer, alpha-olefins other than propylene, such as ethylene, 1-butylene, 1-pentyne, 1-hexene, are preferable, for example.
Examples of the copolymer include block copolymers of propylene and other monomers, and random copolymers of propylene and other monomers.
The other monomers may be used alone or in combination of two or more.

  As a polypropylene resin, high melt tension polypropylene (HMS-PP) resin is preferable. A high melt tension polypropylene resin is a polypropylene resin whose tension in the molten state is increased by mixing a high molecular weight component or a component having a branched structure into the polypropylene resin, or copolymerizing polypropylene with a long chain branched component. is there. High melt tension polypropylene resins are commercially available, for example, "WB130 HMS", "WB 135 HMS", "WB 140 HMS" manufactured by Borealis; "Pro-fax F 814" manufactured by Basell; "FB 3312" manufactured by Japan Polypropylene, " FB5100 "," FB7200 "," FB9100 "," MFX8 "," MFX6 "etc. are mentioned.

Whether a polypropylene-based resin is a high melt tension polypropylene resin can be determined not only by the difference in polymer structure but also by the magnitude of its melt tension (melt tension). For example, if the melt tension is 5 cN or more, it can be judged to be a high melt tension polypropylene resin.
The melt tension of the high melt tension polypropylene resin is preferably, for example, 10 cN or more and 30 cN or less. The intensity | strength of the foam board 1 is easy to be improved more as it is more than the said lower limit. It is easy to improve thermoforming property as it is below the said upper limit.

5.0 g / 10 min or less is preferable, and, as for the melt mass flow rate (MFR) of the polypropylene resin of A layer 10, 0.1 g / 10 min or more and 5.0 g / 10 min or less is more preferable, and 0.5 g / 10 min or more 10 min or less is more preferable. It is easy to make the closed cell rate of A layer 10 70% or more as MFR is more than the above-mentioned lower limit. The intensity | strength of the foam board 1 is easy to be improved more as MFR is below the said upper limit.
MFR is a numerical value showing the fluidity at the time of melting of a thermoplastic resin. The MFR is expressed by the amount of resin extruded per 10 minutes from a die of a specified diameter installed at the bottom of a cylinder by a piston under constant temperature and load conditions and MFR.
In the present specification, MFR is a numerical value at 230 ° C. and 0.23 MPa.

150 degreeC or more and 170 degrees C or less are preferable, and, as for melting | fusing point of the polypropylene resin of A layer 10, 155 degrees C or more and 165 degrees C or less are more preferable. When the melting point of the polypropylene-based resin of the A layer 10 is equal to or more than the above lower limit value, the strength of the foam board 1 can be easily increased. When the melting point of the polypropylene-based resin of the A layer 10 is less than or equal to the above upper limit value, the thermoformability can be easily improved.
The melting point of the polypropylene resin of the A layer 10 is measured by the method described in JIS K 7121: 1987 "Transition temperature measurement method of plastic".

The A layer 10 contains substantially no inorganic filler.
In the present specification, “having substantially no inorganic filler” means that the content of the inorganic filler with respect to the total mass of the A layer 10 is 0.1 mass% or less.
In the present specification, an inorganic filler refers to an inorganic compound used as a filler, and includes calcium carbonate, talc, silica, clay, alumina, mica, titanium oxide, glass beads, glass balloons, carbon fibers, glass fibers, carbon Black, metal powder etc. are mentioned.
The A layer 10 is lightweight because it contains substantially no inorganic filler, and is excellent in thermoforming properties.

The closed cell rate of the A layer 10 is 70% or more, preferably 75% or more, and more preferably 80% or more. The upper limit is not particularly limited, and for example, 99% or less is preferable. It is excellent in impact resistance that the closed cell rate of A layer 10 is in the said numerical range, and it is easy to improve a thermoforming property more.
The closed cell rate of the A layer 10 is measured by the method described in JIS K 7138: 2006 “Hard foam plastic-determination of open cell rate and closed cell rate”.

  The thickness t10 of the A layer 10 is 2.0 to 6.0 mm, preferably 2.5 to 5.5 mm, and more preferably 3.0 to 5.0 mm. When the thickness t10 is equal to or more than the above lower limit value, the heat insulation performance can be further improved. When the thickness t10 is less than or equal to the above upper limit value, the thermoformability can be more easily improved. In addition, thickness t10 is an average value of the thickness of arbitrary 10 points measured by vernier calipers.

The basis weight of the A layer 10 is preferably from 300 to 700 g / ^{m 2,} more preferably 350~650g / ^{m 2,} more preferably 400-600 g / ^{m 2.} The intensity | strength of the foam board 1 is easier to be improved as the basis weight of A layer 10 is more than the said lower limit. It is easy to improve thermoforming property as it is below the said upper limit. The basis weight of the A layer 10 is determined as follows.
Except for 20 mm at both ends in the width direction (TD direction) of the A layer 10, 10 pieces of 10 cm × 10 cm are cut at equal intervals in the width direction, and the mass (g) of each piece is measured to 0.001 g. A value of the average value was converted into mass per 1 m ² of the mass (g) of each section, the basis weight of the A layer 10 (g / ^{m 2).}

100-700 kg / m < ³ > is preferable, as for the density of A layer 10, 150-600 kg / m < ³ > is more preferable, and 150-450 kg / m < ³ > is more preferable. When the density of the A layer 10 is equal to or more than the above lower limit value, the strength can be more easily improved. It is easy to make the foam board 1 lightweight more that it is below the said upper limit.

The expansion ratio of the A layer 10 is preferably 2.0 to 6.0, more preferably 2.0 to 5.0, and still more preferably 2.5 to 4.0. When the expansion ratio of the A layer 10 is equal to or more than the above lower limit value, the heat insulation performance can be further improved. It is easy to improve thermoforming property as it is below the said upper limit.
In addition, the foaming ratio of A layer 10 is calculated | required as follows.
The A layer 10 is cut out to a predetermined size and used as a sample. The size (plan view area: S) and thickness (t) of the sample are measured. The apparent volume (V = S × t (cm ³ )) of the sample is determined by multiplying the sample size by the thickness. The apparent density (d = M / V (g / cm ³ )) of the A layer 10 is calculated from the determined volume and the mass of the sample (M (g)).
Then, the density of the polypropylene resin forming the A layer 10 (for example, ρ: 0.90 g / cm ³ ) is divided by the apparent density (d) of the A layer 10 to obtain the foam of the A layer 10 Find the magnification (magnification).
Expansion ratio (fold) = density of polypropylene resin (ρ) ÷ apparent density of layer 10 (d)

20-200 micrometers is preferable, as for the average bubble diameter of A layer 10, 30-180 micrometers is more preferable, and 50-150 micrometers is more preferable. When the average cell diameter of the A layer 10 is equal to or more than the above lower limit value, the thermoformability can be easily improved. When the average cell diameter of the A layer 10 is less than or equal to the above upper limit, the strength can be easily improved.
The average bubble diameter of the A layer 10 is calculated as follows.
The foam plate 1 is cut, and the cut surface is photographed at a magnification of 18 times using a scanning electron microscope for the part excluding the outer 1/10 of the cut surface thickness direction, and the image of the cut surface is taken Print on paper. Next, 6 arbitrary line segments (length 60 mm) are drawn per sheet, and the average chord length for each line segment is calculated by the following equation from the number of air bubbles overlapping this line segment. However, the line segment should be drawn so that the bubbles do not touch at the contact point as much as possible, and if it touches, it shall be included in the number of bubbles.
Average chord length (t) = length of line segment / (number of bubbles × photo magnification)
Then, the bubble diameter D is calculated by the following equation.
D = t / 0.616
Then, an arithmetic mean value of the bubble diameter D determined for each line segment is determined, and this arithmetic mean value is taken as an average bubble diameter of the A layer 10.
In addition, the average cell diameter of A layer 10 is adjusted with the kind and quantity of polypropylene resin, and the kind and quantity of a foaming agent, and a combination.

As the foaming agent, for example, inorganic degradable foaming agents such as ammonium carbonate, sodium bicarbonate, ammonium bicarbonate, ammonium nitrite, calcium azide, sodium azide, sodium borohydride, etc .; azodicarbonamide, azobissulformamide, azo Azo compounds such as bisisobutyronitrile and diazoaminobenzene; Nitroso compounds such as N, N'-dinitroso pennan methylenetetramine, N, N'-dimethyl-N, N'-dinitrosotephthalamide; benzenesulfonyl hydrazide P-toluenesulfonyl hydrazide, p, p'-oxybisbenzenesulfonyl semicarbazide, p-toluenesulfonyl semicarbazide, trihydrazino triazine, barium azodicarboxylate and the like. Examples of gaseous blowing agents include air, nitrogen, carbon dioxide gas, propane, neopentane, methyl ether, fluoromethane dichloride, n-butane, isobutane and the like. In addition, gas means that it is gas at normal temperature (15 degreeC-25 degreeC) here. On the other hand, volatile foaming agents include ether, petroleum ether, acetone, pentane, hexane, isohexane, heptane, isoheptane, benzene, toluene and the like.
Among the above-mentioned foaming agents, n-butane and nitrogen are particularly preferable.
One of these foaming agents may be used alone, or two or more thereof may be used in combination.

The content of the foaming agent is preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the polypropylene resin.
When the foaming agent is a volatile foaming agent, the content of the volatile foaming agent is 0.5 to 0.5 parts by weight of the polypropylene resin, although it varies depending on the type of the foaming agent, the desired expansion ratio and the like. 20 parts by mass is preferred.

  The A layer 10 may further contain known foaming aids to control the decomposition temperature, the amount of generated gas, and the decomposition rate. Examples of the foaming aid include solvents such as toluene, xylene, ethylbenzene, cyclohexane and D-limonene; and plasticizers (high-boiling point solvents) such as diisobutyl adipate, diacetylated monolaurate and coconut oil. The content of the foaming aid is preferably 0.1 to 2.5 parts by mass with respect to 100 parts by mass of the polypropylene resin.

The A layer 10 may further contain a cell regulator. Examples of the cell regulator include acid salts of polyvalent carboxylic acids, reaction mixtures of polyvalent carboxylic acids with sodium carbonate or sodium bicarbonate, and the like, but from the viewpoint of moldability while maintaining the closed cell rate, a cell regulator Is preferably the above reaction mixture.
The content of the cell regulator is preferably 0.01 to 1.0 parts by mass with respect to 100 parts by mass of the polypropylene resin.
The A layer 10 may further contain a heat stabilizer, an ultraviolet light absorber, an antioxidant, a colorant and the like, as necessary.

The first B layer 20 is a non-foamed resin layer of polypropylene resin provided on one side of the A layer 10. The second B layer 22 is a non-foamed resin layer of polypropylene resin provided on the other surface of the A layer 10. By providing the first B layer 20 on one surface of the A layer 10, the foam board 1 can easily improve the strength. In addition, by providing the second B layer 22 on the other surface of the A layer 10, the foam board 1 can easily maintain its planarity and can suppress warpage, and thus can easily improve thermoforming. Furthermore, by providing the first B layer 20 and the second B layer 22 on both sides of the A layer 10, the foam board 1 conceals the irregularities on the surface of the A layer 10 (conspicuousness), and the appearance design property is improved. It is easy to improve.
In addition, since the first B layer 20 and the second B layer 22 are non-foamed resin layers of polypropylene resins, they have excellent chemical resistance.

As a polypropylene resin which comprises the 1st B layer 20, resin similar to the polypropylene resin which comprises A layer 10 can be used. As a polypropylene resin which comprises the 2nd B layer 22, resin similar to the polypropylene resin which comprises A layer 10 can be used.
The polypropylene resin constituting the first B layer 20 may be the same as or different from the polypropylene resin constituting the A layer 10. The polypropylene resin constituting the second B layer 22 may be the same as or different from the polypropylene resin constituting the A layer 10.
The polypropylene resin constituting the second B layer 22 may be the same as or different from the polypropylene resin constituting the first B layer 20.

The first B layer 20 contains an inorganic filler. In the present specification, an inorganic filler refers to an inorganic compound used as a filler, and includes calcium carbonate, talc, silica, clay, alumina, mica, titanium oxide, glass beads, glass balloons, carbon fibers, glass fibers, carbon Black, metal powder etc. are mentioned. As an inorganic filler used for the first B layer 20, calcium carbonate and talc are preferable.
The first B layer 20 is more excellent in strength because it contains an inorganic filler.

  The content of the inorganic filler in the first B layer 20 is 5 to 40% by mass, preferably 10 to 35% by mass, and more preferably 15 to 30% by mass with respect to the total mass of the first B layer 20. preferable. The intensity | strength of the foam board 1 is easier to be improved as content of the inorganic filler in the 1st B layer 20 is more than the said lower limit. When the content of the inorganic filler in the first B layer 20 is less than or equal to the above upper limit value, the appearance design and the thermoformability can be easily improved.

The inorganic filler used for the second B layer 22 is the same as the inorganic filler used for the first B layer 20. The inorganic filler used for the second B layer 22 may be the same as or different from the inorganic filler used for the first B layer 20.
The content of the inorganic filler in the second B layer 22 may be the same as or different from the content of the inorganic filler in the first B layer 20.

The MFR of the polypropylene resin of the first B layer 20 is preferably 5.0 g / 10 min or less, more preferably 0.1 g / 10 min or more and 5.0 g / 10 min or less, and more preferably 0.5 g / 10 min or more and 4.0 g / 10 min The following are more preferable. It is easy to improve the intensity of foam board 1 as MFR is more than the above-mentioned lower limit. When the MFR is less than or equal to the above upper limit, the appearance designability and the thermoformability can be further improved. The MFR of the polypropylene resin of the first B layer 20 is a numerical value at 230 ° C. and 0.23 MPa.
The MFR of the second B layer 22 may be the same as or different from the MFR of the first B layer 20.

150 degreeC or more and 170 degrees C or less are preferable, and, as for melting | fusing point of the polypropylene resin of the 1st B layer 20, 155 degrees C or more and 165 degrees C or less are more preferable. When the melting point of the polypropylene-based resin of the first B layer 20 is equal to or more than the above lower limit value, the strength of the foam board 1 can be easily increased. When the melting point of the polypropylene-based resin of the first B layer 20 is less than or equal to the above upper limit value, the thermoformability can be more easily improved.
The melting point of the polypropylene resin of the first B layer 20 can be measured by the same method as the melting point of the polypropylene resin of the A layer 10.
The melting point of the polypropylene resin of the second B layer 22 may be the same as or different from the melting point of the polypropylene resin of the first B layer 20.

The thickness t20 of the first B layer 20 is preferably 0.05 to 0.25 mm, more preferably 0.075 to 0.25 mm, and still more preferably 0.10 to 0.20 mm. The intensity | strength of the foam board 1 is easier to be improved as the thickness t20 is more than the said lower limit. When the thickness t20 is less than or equal to the above upper limit value, the thermoformability can be more easily improved. The thickness t20 is determined in the same manner as the thickness t10 of the A layer 10.
The thickness t22 of the second B layer 22 may be the same as or different from the thickness t20 of the first B layer 20.

The basis weight of the first B layer 20 is preferably from 50 to 250 g / ^{m 2,} more preferably 75~225g / ^{m 2,} more preferably 100 to 200 g / ^{m 2.} When the basis weight of the first B layer 20 is equal to or more than the above lower limit value, the strength of the foam board 1 can be easily improved. It is easy to improve thermoforming property as it is below the said upper limit.
The basis weight of the second B layer 22 may be the same as or different from the basis weight of the first B layer 20.

  The first C layer 30 is a non-foamed resin layer of a polyolefin resin or a polyester resin provided on the first B layer 20. The first C layer 30 is a thin film-like layer having a thin surface and having a gloss, and is located on the surface of the foam board 1, so the appearance design can be easily improved. In addition, since the first C layer 30 is made of a resin having a melting point lower than that of the resins of the A layer 10 and the first B layer 20, the elongation at the time of thermoforming is good. It is possible to suppress the occurrence of a crack and to easily improve the thermoforming property. In addition, since the first C layer 30 is excellent in low temperature brittleness and can suppress the surface of the foam plate 1 from being scratched, the strength of the foam plate 1 can be easily improved. The first C layer 30 functions as a surface resin layer.

The foam board 1 includes a second C layer 32 provided on the second B layer 22. The second C layer 32 is a non-foamed resin layer of a polyolefin resin or a polyester resin.
The second C layer 32 is similar to the first C layer 30 and functions as a surface resin layer. The second C layer 32 may be the same as or different from the first C layer 30.

As polyolefin resin which comprises the 1st C layer 30, polyolefin resin films, such as a polyethylene film and a polypropylene film, are mentioned, for example.
Examples of the polyester-based resin constituting the first C layer 30 include polyethylene terephthalate resin, polybutylene terephthalate resin, polyethylene naphthalate resin, polyethylene furanoate resin, polybutylene naphthalate resin, terephthalic acid, ethylene glycol and cyclohexane di- Copolymers with methanol, and mixtures of these, and mixtures of these with other resins may, for example, be mentioned. Also, plant-derived polyethylene terephthalate resin and polyethylene furanoate resin may be used. One of these polyester resins may be used alone, or two or more thereof may be used in combination. Particularly preferred polyester resins are polyethylene terephthalate resins.
When the other resin is mixed as the polyester resin, the content of the other resin is preferably less than 50% by mass with respect to the total mass of the polyester resin.
The resin constituting the first C layer 30 is preferably a polyolefin-based resin from the viewpoint of enhancing the thermoforming property, and from the viewpoint of improving oil resistance, more preferably a polypropylene-based resin, and a non-oriented polypropylene (CPP) film More preferable.

The resin constituting the first C layer 30 may be a propylene homopolymer, a copolymer having about 1 to 7% by mass of ethylene or other comonomer inserted in a propylene molecular chain, usually in a matrix of propylene homopolymer. Impact copolymers (also referred to as block copolymers) containing up to about 20% ethylene-propylene rubber (EPR) can each be used alone or mixtures of these. In addition, other resins may be mixed with the resin for film as long as the effects of the present invention are not impaired. As the other resin, for example, homopolymers or copolymers of ethylene, butene, α-olefin, etc., olefin resins such as polyolefin wax, polyolefin elastomer, hydrocarbon resins such as petroleum resin, terpene resin, etc. A resin or the like is used singly or in combination of two or more.
The resin that constitutes the second C layer 32 may be the same as or different from the resin that constitutes the first C layer 30.

The melting point of the resin forming the first C layer 30 is lower than the melting point of the resin of the A layer 10 and the first B layer 20 adjacent to the first C layer 30. 130 degreeC or more and less than 150 degreeC are preferable, and, as for melting | fusing point of resin which comprises the 1st C layer 30, 135 degreeC or more and 145 degrees C or less are more preferable, for example. When the melting point of the resin constituting the first C layer 30 is equal to or more than the above lower limit value, the low temperature brittleness of the foam board 1 can be easily enhanced. When the melting point of the resin forming the first C layer 30 is less than or equal to the above upper limit value, the thermoformability can be more easily improved.
The melting point of the resin constituting the first C layer 30 can be measured by the same method as the melting point of the polypropylene resin of the A layer 10.
The melting point of the resin constituting the second C layer 32 may be the same as or different from the melting point of the resin constituting the first C layer 30.

The surface glossiness of the first C layer 30 is 60% or more, preferably 70% or more, more preferably 80% or more, and still more preferably 90% or more. The upper limit of the surface glossiness of the first C layer 30 is not particularly limited, and for example, 99% or less is preferable.
When the surface glossiness of the first C layer 30 is within the above numerical range, the appearance design can be further improved.
The surface glossiness of the first C layer 30 can be measured by the 60 ° specular gloss method described in JIS Z8741: 1997 “Specular glossiness-measurement method”.
The surface glossiness of the second C layer 32 may be the same as or different from the surface glossiness of the first C layer 30.

15 micrometers or less are preferable and, as for the centerline average roughness of the 1st C layer 30, 10 micrometers or less are more preferable. When the center line average roughness of the first C layer 30 is equal to or less than the above upper limit value, the surface glossiness can be easily made 60% or more.
The centerline average roughness of the first C layer 30 is the centerline average roughness described in JIS B0601: 2013 "Geometrical property specification (GPS)-surface properties of products: contour curve method-terms, definition and surface property parameters". Can be measured by
The centerline average roughness of the second C layer 32 may be the same as or different from the centerline average roughness of the first C layer 30.

The thickness t30 of the first C layer 30 is 0.02 to 0.10 mm, preferably 0.025 to 0.08 mm, more preferably 0.025 to 0.05 mm, and 0.025 to 0.035 mm. Is more preferred. When the thickness t30 is equal to or more than the above lower limit value, the concealing property is improved and the appearance design is easily improved. The intensity | strength of the foam board 1 is easier to be improved as the thickness t30 is below the said upper limit. The thickness t30 is determined in the same manner as the thickness t10 of the A layer 10.
The thickness t32 of the second C layer 32 is the same as the thickness t30 of the first C layer 30. The thickness t32 and the thickness t30 may be the same or different.

  If necessary, the first C layer 30 has an antistatic agent, an antifogging agent, an antiblocking agent, an antioxidant, a light stabilizer, a crystal nucleating agent, a lubricant, and a purpose of imparting slip and antiblocking properties. You may add suitably various additives, such as surfactant and a filler, in the range which does not impair the effect of this invention.

  The first C layer 30 is preferably heat-sealed by sandwiching an adhesive film having adhesiveness between the first B layer 20 and the first C layer 30. Alternatively, it is preferable to apply an adhesive between the first B layer 20 and the first C layer 30 to bond them together.

In the present embodiment, a first adhesive layer (not shown) made of an adhesive is provided between the first B layer 20 and the first C layer 30. The adhesive constituting the first adhesive layer may be any adhesive as long as it can bond the first B layer 20 and the first C layer 30, and is a known adhesive generally used for resin films. Can be used. Examples of the adhesive constituting the first adhesive layer include a thermosetting resin adhesive, an elastomer adhesive, an emulsion adhesive, a hot melt adhesive and the like, and a thermosetting resin having excellent durability. Adhesives and hot-melt adhesives with low environmental impact are preferred.
Examples of the thermosetting resin-based adhesive include, for example, a two-component reactive urethane-based adhesive (for example, manufactured by Toyo Morton Co., product number: TM329).
Examples of the hot melt adhesive include polyolefin hot melt adhesives, polyester hot melt adhesives and the like. As a polyolefin type hot melt adhesive, trade name "X-2200" (made by Kurabo Industries) etc. are mentioned, for example. Examples of polyester-based hot melt adhesives include trade name "PES-111EE" (manufactured by Toagosei Co., Ltd.).
The hot melt adhesive may be used alone or in combination of two or more.

  In the present embodiment, a second adhesive layer (not shown) made of an adhesive is provided between the second B layer 22 and the second C layer 32. The second adhesive layer is similar to the first adhesive layer. The second adhesive layer may be the same as or different from the first adhesive layer.

10-50 micrometers is preferable and, as for the thickness of a 1st contact bonding layer, 20-40 micrometers is more preferable. It is easy to adhere | attach the 1st B layer 20 and the 1st C layer 30 enough that the thickness of a 1st contact bonding layer is more than the said lower limit. If it is below the above-mentioned upper limit, the amount of heat applied at the time of bonding can be suppressed low, so that the dimensional change can be reduced and the bonding process can be stabilized.
The thickness of the second adhesive layer may be the same as or different from the thickness of the first adhesive layer.

  2.0-7.0 mm is preferable, as for whole thickness T1 of the foam board 1, 2.1-6.7 mm is more preferable, 2.7-6.2 mm is more preferable, 3.2-5.5 mm Is particularly preferred. It is easy to improve the intensity of foam board 1 as thickness T1 is more than the above-mentioned lower limit. When the thickness T1 is less than or equal to the above upper limit value, it is easy to improve the thermoformability.

Foam board 1 may further laminate a printing film on a surface resin layer. As a printing film, the polyolefin resin film which can be laminated to the 1st C layer 30, for example, a polypropylene resin film, is suitable. The printed film may be adhered to the first C layer 30 via a binder resin, and as the binder resin, for example, a polyester resin film or a polystyrene resin film can also be used.
The printing film may be laminated on the second C layer 32.

The manufacturing method of the resin-laminated foam board 1 is not specifically limited, The manufacturing method of the well-known resin-laminated foam board and the manufacturing method of the lamination sheet for thermoforming of patent document 1 can be used.
The foam board 1 can be manufactured, for example, by the following method.
In a plurality of extruders, melt the resin material of A layer 10, first B layer 20, second B layer 22, first C layer 30 and second C layer 32 from die for coextrusion It can be produced by coextrusion foaming. In the material resin, in the extruder for forming the layer A 10, the foaming agent is kneaded with the resin.
In addition, you may use not only the co-extrusion-foaming method, but after extruding each layer separately, these may be overlap | superposed and laminated | stacked and integrated by thermal lamination and extrusion lamination. Alternatively, a method may be used in which the first B layer 20 and the first C layer 30 are laminated in advance, and the first B layer 20 and the first C layer 30 are laminated on the separately prepared A layer 10 and laminated and integrated by thermal lamination.

In addition, the resin laminated foam board of this invention is not limited to above-described foam board 1. As shown in FIG. For example, the resin-laminated foam board of the present invention may be an embodiment in which the second C layer 32 is not provided on the second B layer 22. The resin-laminated foam board of the present invention may be an embodiment in which the first B layer 20 and the first C layer 30 are directly heat-sealed without interposing the first adhesive layer. From the viewpoint of further improving the strength and the appearance design of the foam board, the foam board preferably includes both the first C layer 30 and the second C layer 32.
The resin-laminated foam board of the present invention may have an embodiment in which the first C layer 30 is not provided on the first B layer 20. The resin-laminated foam board of the present invention may be an embodiment in which the second B layer 22 and the second C layer 32 are directly heat-sealed without the second adhesive layer.

  The first C layer 30 may be provided on the second B layer 22 in the resin-laminated foam board of the present invention. In the resin-laminated foam board of the present invention, the second C layer 32 may be provided on the first B layer 20.

Since the resin-laminated foam board of the present invention has the layer A, it is excellent in impact resistance. Moreover, since the foam board of this invention has B layer containing an inorganic filler, it is excellent by intensity | strength.
In addition, since the foam board of the present invention has a C layer as a surface resin layer, it is excellent in appearance designability, thermoformability and low temperature brittleness.

  The thermoformed article of the present invention is obtained by thermoforming the foam board of the present invention. This thermoforming can be performed using the same method and apparatus as production of various thermoformed articles using a thermoplastic resin foam sheet.

  Although the temperature at the time of thermoforming depends on the mold for molding, for example, 200 to 300 ° C. is preferable. It is easy to thermoform a foam board in a desired shape as the temperature at the time of thermoforming is more than the above-mentioned lower limit. It is easy to hold | maintain the external appearance designability of a thermoformed article as the temperature at the time of thermoforming is below the said upper limit.

  The thermoforming time is preferably, for example, 15 to 30 seconds. It is easy to thermoform a foam board in a desired shape as time of thermoforming is more than the above-mentioned lower limit. It is easy to hold | maintain the external appearance designability of a thermoformed article as the temperature of thermoforming is below the said upper limit.

Since the melting point of the resin forming the surface resin layer is lower than the melting point of the resin forming the adjacent B layer, the thermoformed article of the present invention is excellent in low temperature brittleness and more excellent in strength. In addition, in the thermoformed article of the present invention, the surface resin layer is easily extended at the time of thermoforming, and is excellent in thermoformability. Furthermore, since the surface resin layer has smoothness and the surface glossiness is 60% or more, the thermoformed article of the present invention is excellent in appearance design.
The thermoformed article of the present invention is excellent in thermoformability, so that a thermoformed article having a desired shape can be easily produced.

FIG. 2 shows a perspective view of an assembly box according to an embodiment of the present invention.
The assembly box 100 includes a bottom plate 102 and a side plate 101. The side plate 101 is the foam plate 1 of the present invention. The bottom plate 102 is a thermoformed article of the present invention.
The bottom plate 102 is rectangular in plan view. The bottom plate 102 has a protrusion 103, a protrusion 104, and a recess 105. The ridges 104 run along the outer edge of the bottom plate 102. The ridges 103 circulate along the ridges 104. The ridges 103 and the ridges 104 form a groove 105 between them.

The four side plates 101 are joined in a square tube shape. The lower ends of the four side plates 101 are fitted to the concave streaks 105 of the bottom plate 102.
The assembly box 100 can be easily assembled in this manner, and after use, the side plate 101 can be easily removed from the bottom plate 102. The side plates 101 removed from the bottom plate 102 can be easily unjoined one by one, and by stacking them, space saving of the storage place can be achieved. In addition, transportation of the side plate 101 can be facilitated.
If the assembly box 100 becomes dirty after use, it can be used repeatedly by washing the four side plates 101 and the bottom plate 102 respectively.

  The method of joining the four side plates 101 into a square tube shape is not particularly limited, and may be joined using, for example, an adhesive or an adhesive tape, or may be joined by cutting into each other. It is preferable that the four side plates 101 be cut and joined to each other from the viewpoint of easily assembling the assembly box 100 and releasing the joint easily.

Since the surface resin layer of the foam board 1 of the present invention is excellent in oil resistance and strength, it is preferable that the surface resin layer is configured to face the inner surface of the assembly box 100. When an antimicrobial coat or the like is applied to the surface resin layer, the product accommodated in the assembly box 100 is kept clean.
In addition, when the surface resin layer is configured to face the outer surface of the assembly box 100, the assembly box 100 is excellent in impact resistance against dropping or the like.
Therefore, the surface resin layer is more preferably provided on both sides of the foam plate 1.
When a printing film is provided on the surface of the side plate 101, the appearance design can be improved by arranging the printing film on the outside of the assembly box 100. In addition, the product name in the assembly box 100, the name of the seller, etc. may be described by printing film.

The side plate 101 and the bottom plate 102 have an A layer made of a polypropylene resin. In addition, the side plate 101 and the bottom plate 102 have a B layer made of a polypropylene resin.
Therefore, from the viewpoint of recycling the assembly box 100, the surface resin layers of the side plate 101 and the bottom plate 102 are preferably made of the same polypropylene-based resin as the A layer and the B layer.

  The assembly box of the present invention is not limited to the assembly box 100, and the bottom plate 102 may apply the foam plate 1 which is not thermoformed. The side plate 101 may be a thermoformed product obtained by thermoforming the foam plate 1. That is, the assembly box of the present invention may be configured by the foam plate 1 in which the bottom plate and the side plate are not thermoformed, and the bottom plate and the side plate may be configured by the thermoformed product.

  The bottom plate 102 of the assembly box of the present invention may be formed with asperities according to the shape of the product to be accommodated. Alternatively, the bottom plate 102 may be provided with a plurality of grooves, and the partition plate may be arranged in the housing portion of the assembly box.

The assembly box of the present invention may use two bottom plates 102 and use one bottom plate 102 as a canopy of the assembly box.
Two or more assembly boxes can be stacked in the height direction to save storage space.

The shape of the assembly box of the present invention may be a rectangular parallelepiped or a cube. The shape of the assembly box can be adjusted by appropriately changing the length for cutting the side plate and the bottom plate.
The shape of the assembly box of the present invention is not limited to a rectangular parallelepiped, and may be a pentagonal or hexagonal wedge shape in plan view, or may be a tray-like shape in which the height of the side plate is lowered.
In the assembly box of the present invention, the side plate may be thermoformed into a curved surface shape, and may be formed into a bowl shape having a circular shape in plan view or an oval shape in plan view.

The assembly box of the present invention is excellent in appearance designability because it is composed of a thermoformed article excellent in thermoforming property and a foam board excellent in appearance designability. In addition, the assembly box of the present invention is more excellent in strength because it is composed of a thermoformed article excellent in strength and a foam plate.
Furthermore, in the assembly box of the present invention, since the side plate and the bottom plate can be easily fitted, improvement in the efficiency of manufacturing the assembly box and cost reduction by not using an adhesive can be expected.
Moreover, since the assembly box of the present invention can easily release the fitting of the side plates and the bottom plate and the joining of the side plates, space saving of the storage place of the assembly box can be achieved. In addition, the side plates and the bottom plate may be separately washed to be used repeatedly, or the side plates and the bottom plate may be melted to be used as materials for recycling.

  Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited by the following description.

Example 1
45% by mass of “WB140 HMS” (melt tension 23 cN, MFR = 1.7 g / 10 min) manufactured by Borealis as a polypropylene resin for layer A, and “BC6C” manufactured by Japan Polypropylene Corp. as a block PP A resin component containing 45% by mass and 10% by mass of “Q-100F” as a polyolefin-based thermoplastic elastomer (TPO), and the proportion with respect to 100 parts by mass of the resin component is 0.2 parts by mass Second extrusion with a diameter of 115 mm at the tip of the first extruder with a diameter of 90 mm using a resin blended with baking soda-citric acid based foaming agent (master batch made by Dainichi Seika Co., Ltd., trade name "Finecell master PO410K") A tandem extruder was prepared by connecting the machines. Then, a polypropylene-based resin is supplied to the first extruder of this tandem extruder, melt-kneaded at about 200 to 210 ° C., and then butane (normal butane / isobutane (mass) as a foaming agent in the first extruder. Ratio) (65/35) 3.0 parts by mass is injected and melt-kneaded, cooled to about 175 ° C., and supplied to an annular die connected to the tip of the second extruder to make it cylindrical It was extruded and foamed at an extrusion rate of 150 kg / hour.
The obtained cylindrical foam is cooled by blowing air on its inner surface, and then the cooling mandrel plug is placed along the inner surface to solidify the inner surface, and the outer surface is also cooled and solidified on the plug by cooling air. The cylindrical foam was continuously wound in the extrusion direction (MD direction) across the inner and outer peripheral surfaces, and was rolled up as a continuous sheet. As a result, a polypropylene resin foamed sheet (A layer) having a basis weight of 560 g / m ² and a thickness of 5.0 mm could be stably obtained.

43 parts of Talpet 70P (manufactured by Nitto Powder Co., Ltd.) containing 70% by mass of inorganic filler in 57% by mass of BC6C (block PP, manufactured by Japan Polypropylene Corp.) (MFR = 2.5) as B layer in the obtained foam sheet % And blended to 30% by mass of the inorganic filler. The polypropylene resin was fed to each of two extruders. A sheet in a molten state immediately after being extruded from a T-die attached to the tip of the first extruder was laminated on one side of the above-mentioned polypropylene resin foamed sheet and thermally fused and integrated. At the same time, a sheet in a molten state immediately after being extruded from a T-die attached to the tip of a second extruder is laminated on the other side of the polypropylene resin foam sheet and heat fusion is integrated to form polypropylene on both sides. The resin layer (B layer) was laminated to obtain a laminated sheet. The resulting laminated sheet had a basis weight of 860 g / m ² and a thickness of 5.2 mm. In addition, extrusion conditions of the 2nd extruder of 2 machines were made the same conditions.
The temperatures of the remaining parts other than the two ends of the T extruder attached to the tip of the second extruder of the two machines are such that the temperature at both ends in the width direction (TD direction) in the resin flow channel is 240 ° C. The temperature was adjusted to 260 ° C.

On one side of the above laminated sheet, 30 μm of C layer (CPP film, manufactured by Towa Chemical Industry Co., Ltd.) was laminated by a heat roll through a hot melt adhesive film (trade name “X-2200” manufactured by Kurabo) with a thickness of 20 μm. .
The foam board which has a layer structure shown in Table 1 was obtained by the above process. The B layer shown in Table 1 represents the first B layer, and the second B layer also had the same physical properties. The C layer shown in Table 1 represents a first C layer, and the second C layer also has the same physical properties.

[Examples 2 to 5, Comparative Examples 1 to 9]
Under the same conditions as in Example 1, the amount of pressing of the foaming agent, the amount of discharge, and the take-up speed were appropriately adjusted to obtain a layer configuration having the physical properties shown in Table 1, to obtain a foam plate.
In Example 3, E111G (homoPP, manufactured by Prime Polymer, MFR = 0.5, melting point 163 ° C.) was used as the resin component of the B layer.
In Comparative Examples 3, 5, 7 and 8, in order to obtain a predetermined thickness, a foam board was obtained in which the foaming ratio of the layer A was suppressed, with the amount of pressing of the foaming agent being 1.5 to 2.5 parts by mass. .

Comparative Example 10
As a polypropylene resin for A layer, 27 mass% of "WB140HMS", 25 mass% of "BC6C", 5 mass% of "Q-100F", and 43 mass% of "Talpet 70P" were blended. It cooled to 185 degreeC by making the pressing amount of a foaming agent into 1.3 mass parts, and the conditions other than that were made to be the same as that of Example 1, and the foam board was obtained.

  Various physical property tests were performed using the foam board of each obtained example. The evaluation method is shown below, and the evaluation results are shown in Table 2.

[Bending strength]
The bending strength in the MD direction and the TD direction was measured under the following conditions using a test piece cut out to a size of width 50 mm × length 150 mm × thickness (thickness of each example).
(Test conditions)
Measuring apparatus: Tensilon universal testing machine RTG-1310 (manufactured by A & G Co.).
n number: three.
Test speed: 50 mm / min.
Distance between supporting points: 100 mm.
Tip jig: Pressure wedge 5R.
Support stand: 2.5R.
The arithmetically averaged value of the obtained bending strength is taken as bending strength (MPa) in each direction, and is shown in Table 2. The larger the value of the bending strength, the more rigid the foam board is, and the better the strength.

[Evaluation of thermoformability]
The foam board of each of the obtained examples was thermoformed (temperature 260 ° C., time 17 seconds) to produce a thermoformed article to be a bottom board.
The obtained thermoformed article was allowed to stand for 2 hours in an environment of 23 ± 2 ° C. and humidity of 50 ± 5% RH. Thereafter, the surface of the thermoformed article was visually confirmed, and the thermoformability was evaluated according to the following evaluation criteria.
(Evaluation criteria)
Good: The film on the surface is smooth, no peeling, etc., and the thermoforming property is good.
Δ: The film on the surface is smooth but there is peeling and the like, and the thermoforming property is inferior.
X: The film on the surface has irregularities, and peeling and the like.

[Evaluation of appearance design]
Using the foam board of each obtained example, the surface glossiness of the surface resin layer was measured in accordance with the 60-degree mirror gloss method described in JIS Z8741: 1997 "mirror surface glossiness-measurement method".
The appearance design was evaluated according to the following evaluation criteria using Gloss Checker IG 320 (manufactured by Horiba, Ltd.). The results are shown in Tables 1 and 2.
(Evaluation criteria)
○: The surface glossiness is 60% or more.
X: Surface glossiness less than 60%.

[Evaluation of low temperature brittleness]
The thermoformed product obtained in each example was used as a bottom plate, and a foam plate having a length of 160 mm, a width of 100 mm, and a height of 35 mm was produced using the foam plate of the same example and the same comparative example as side plates.
In addition, the molded article was produced so that the surface resin layer of a baseplate and all the side plates faced the outer surface at this time.
The resulting molded article was charged with 200 g of water and allowed to stand for 24 hours in a -20 ° C freezer to freeze the water. This molded article was dropped from a height of 500 mm, and the change in the shape of the molded article was visually confirmed, and the low temperature brittleness was evaluated according to the following evaluation criteria. The results are shown in Table 2. The low temperature brittleness is an index indicating the strength of a molded article assuming an assembly box.
(Evaluation criteria)
:: Although there is a dent, the shape of the molded article is maintained.
Δ: Cracks (cracks) occur.
X: A crack (a state in which a void is present in the crack) occurs or the shape of the molded product is broken.

  In Examples 1 to 5 to which the present invention is applied, all evaluations of thermoformability, appearance designability, and low temperature brittleness were “o”. On the other hand, in Comparative Example 1 in which a resin having a high melting point was used for the layer (C), the thermoformability and the appearance design were “x”. Thermoforming property was "x" in Comparative Example 2 in which the content of the inorganic filler is large. In Comparative Examples 3, 5 and 8 in which the thickness of the A layer is small, the low temperature brittleness was “x”, and the strength was inferior. The comparative example 4 which does not contain an inorganic filler in B layer was inferior in intensity | strength in thermoforming property and low-temperature brittleness by "(triangle | delta)". In Comparative Example 6 in which a resin having a high melting point was used for the C layer, the thermoforming property was “×”. In Comparative Examples 7 and 10 in which the closed cell rate of the A layer is less than 70%, the thermoforming property and the low temperature brittleness were “Δ”, and the strength was inferior. The comparative example 9 using the resin film with low surface glossiness was "x" in appearance designability.

  From these results, it was found that according to the resin-laminated foam plate of the present invention, the thermoformability and the appearance design are excellent, and the strength is more excellent.

DESCRIPTION OF SYMBOLS 1 resin laminated foam board 10 A layer 20 1st B layer 22 2nd B layer 30 1st C layer 32 2nd C layer 100 assembly box 101 side plate 102 bottom plate 103, 104 convex streak 105 concave streak

Claims (5)

A foamed resin layer (A) of a polypropylene resin, a non-foamed resin layer (B) of a polypropylene resin provided on both sides thereof, and a polyolefin resin provided on at least one of the non-foamed resin layers (B) Or a non-foamed resin layer (C) of polyester resin, which is a resin-laminated foam plate,
The foamed resin layer (A) has a closed cell ratio of 70% or more, a thickness of 2.0 to 6.0 mm, and substantially does not contain an inorganic filler,
The non-foamed resin layer (B) contains 5 to 40% by mass of the inorganic filler based on the total mass of the non-foamed resin layer (B),
The melting point of the resin of the non-foamed resin layer (C) is lower than the melting point of the resin of the foamed resin layer (A), and the non-foamed resin layer (B) adjacent to the non-foamed resin layer (C) Lower than the melting point of the
The non-foamed resin layer (C) has a surface gloss of 60% or more and a thickness of 0.02 to 0.10 mm.   The melt mass flow rate (MFR) at 230 ° C. and 0.23 MPa of the resin of the foamed resin layer (A) and the resin of the non-foamed resin layer (B) is 5.0 g / 10 min or less. Resin laminated foam board. The resin laminated foam board of Claim 1 or 2 whose density of the said foamed resin layer (A) is 100-700 kg / m < ³ >, and the average cell diameter of the said foamed resin layer (A) is 20-200 micrometers.   The thermoformed article formed by thermoforming the resin-laminated foam board as described in any one of Claims 1-3.   An assembly box comprising the thermoformed article according to claim 4 as a bottom plate and the resin-laminated foam plate according to any one of claims 1 to 3 as a side plate.

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