KR102306526B1 - Foamed member, electric or electronic device, and production method for foam - Google Patents

Abstract

Provided is a foam member having a foam obtained with good moldability, good pick-up properties of the foam itself, and less prone to foam breakage when peeled from the carrier tape, and having a wide selection range of such a carrier tape.
It is a single sheet-like foam, and the content of the lubricant in a region from one surface of the foam to a depth of 50 nm in the thickness direction is the thickness from the cut surface when the foam is cut parallel to the foam surface so that the thickness becomes half The foam member which has a foam whose content is 70 weight% or less of the lubricant in the area|region up to the depth of 50 nm in a direction.

Description

A foaming member, an electric and electronic device, and the manufacturing method of a foam TECHNICAL FIELD

The present invention relates to a foamed member having a foamed body, an electric/electronic device having the foamed member, and a method for producing the foamed body.

Generally, a resin foam is made to correspond to the shape of the member used, and is punched out into a required shape, and is used. In recent years, the member area is becoming small by high functionalization and thinning of an electronic device, and the shape of a resin foam is also becoming smaller. In a resin foam used for electronic devices, a high-strength adhesive tape for fixing is pasted on one side and fixed at a predetermined position to perform assembly of the member. Carrier tape is sometimes used to transport to the location of In addition, when using a carrier tape, various processes (a punching process, an adhesion process, etc.) may be given to the resin foam in the state adhere|attached to the carrier tape. Thus, various processes are given to the resin foam used for an electronic device in the state adhere|attached to a carrier tape, or it is conveying with a carrier tape after various processes.

However, when a carrier tape having low adhesive strength is used, the adhesion area with the carrier tape cannot be increased because air bubbles are present on the surface of the resin foam, and the resin foam cannot be lifted by the carrier tape, that is, poor pickup properties. A problem has occurred. On the other hand, when a carrier tape with high adhesive force was used, a problem occurred that foam breakage (breakage of the cell structure in the foam) occurred at the time of peeling.

In order to improve the adhesiveness and sealing property of a resin foam, the method of providing another resin layer on the surface of a resin foam is known. For example, for the purpose of improving sealing properties, a foam in which a soft film softer than a rubber foam is provided on one of the upper and lower surfaces of a rubber foam having both closed-cell and open-celled cells has been proposed (see Patent Document 1). In addition, in patent document 1, about the reinforcement of a foam, or shipment by a carrier tape, it was not considered. In addition, by forming a layer containing a urethane-based thermoplastic polymer composition on the surface of the polyolefin-based resin foam, and applying a surface treatment layer containing a polar polymer on the layer, a foam excellent in toughness, scratch resistance, abrasion resistance, etc. is proposed (see Patent Document 2). In addition, there are also proposed a foam having a surface treated with a polychloroprene-based adhesive composition (see Patent Document 3), a foam having an easy-to-accept layer such as a polyvinyl alcohol layer on the surface (see Patent Document 4), and the like.

In addition, by increasing the interlayer strength of the foam, even if it is a resin foam having a high expansion ratio, it is possible to suppress or prevent foam breakage when peeled from the carrier tape. For example, the resin foam which is hold|maintained by a carrier tape and is excellent in processability and conveyance property is proposed (refer patent document 5).

Japanese Patent Laid-Open No. 9-131822 Japanese Patent Laid-Open No. 2003-136647 Japanese Patent Laid-Open No. 5-24143 Japanese Patent Laid-Open No. 10-37328 Japanese Patent Laid-Open No. 2014-139287

However, since all of the foams proposed by Patent Documents 1 to 4 laminate different materials on the foam, there is a risk of reducing the required physical properties of the foam, and the manufacturing process thereof is also complicated. Moreover, when the carrier tape of specific adhesive force is used for the foam proposed by patent document 5, although various processes become easy, there are few usable carrier tapes, and the selection range was narrow. For this reason, without using another layer for improving the pick-up property, the foam itself has excellent pick-up properties, and foam breakage is unlikely to occur when the foam is peeled from the carrier tape, and the selection range of the usable carrier tape is wide. Foam was desired.

As a result of examining the cause of the narrow selection range of a carrier tape having excellent pick-up properties to the foam itself and difficult to cause foam breakage, the present inventors considered several factors, but thought that the lubricant added at the time of foam molding was the main factor. Specifically, it was thought that the lubricant present on the surface of the resin foam caused a decrease in the adhesion to the carrier tape. On the other hand, when a lubricant is not added at the time of foam molding, the fluidity|liquidity of the resin composition which forms a foam falls remarkably, and molding, such as extrusion molding, becomes difficult. By adding a lubricating agent, the fluidity|liquidity of a resin composition improves, moldability becomes favorable, and shaping|molding becomes easy.

Therefore, the object of the present invention is a foamed product having good moldability, good pick-up properties of the foam itself, less likely to break the foam when peeled from the carrier tape, and a wide selection range of such a carrier tape. to provide the absence.

Another object of the present invention is to provide an electric/electronic device having such a foam member.

Another object of the present invention is to produce a foam that is obtained with good moldability, has good pick-up properties of the foam itself, is less prone to foam breakage when peeled from a carrier tape, and has a wide selection range of such a carrier tape. to provide a way to do it.

As a result of intensive studies to achieve the above object, the present inventors have made a difference between the amount of lubricant inside the foam and the amount of lubricant on the surface, and by making the amount of lubricant on the surface to a specific ratio or less than the amount of lubricant inside, the resin composition A carrier that has good moldability from a carrier, does not use another layer for imparting pick-up properties, has good pick-up properties, and is unlikely to cause foam breakage when peeled off from a carrier tape, and has good pick-up properties and is less likely to cause foam breakage It has been found that foams with a wide selection of tapes are obtained. The present invention has been completed based on these findings.

That is, the present invention is a single sheet-like foam, and the content of the lubricant in the region from one surface of the foam to a depth of 50 nm in the thickness direction is cut parallel to the surface of the foam so that the foam is half the thickness. The foam member which has a foam which is 70 weight% or less of content of the lubricant in the area|region from the cutting surface at the time of thickness direction to the depth of 50 nm is provided.

In the foam member, it is preferable that the foam has an apparent density of 0.01 to 0.20 g/cm ³ , a repulsive force at 50% compression of 0.1 to 4.0 N/cm ² , and an average cell diameter of 10 to 200 μm.

In the foam member, the pressure-sensitive adhesive sheet having an adhesive force (temperature: 23±2°C, humidity: 50±5RH%, tensile rate: 0.3 m/min) of 0.15 N/20 mm to the one surface of the foam and the SUS plate. The peeling force (temperature: 23±2° C., humidity: 50±5RH%, tensile rate: 0.3 m/min) when the adhesive surface of It is preferable to be

In the foam member, the pressure-sensitive adhesive sheet having an adhesive force (temperature: 23±2° C., humidity: 50±5RH%, tensile rate: 0.3 m/min) of 0.35 N/20 mm to the one surface of the foam and the SUS plate. The peeling force (temperature: 23±2° C., humidity: 50±5RH%, tensile rate: 0.3 m/min) when the adhesive surface of It is preferable to be

The said foam member may have an adhesive layer on the other surface of the said foam.

The foam member may be a foam member having a carrier tape having a pressure-sensitive adhesive layer on at least one side of the substrate, and the foam and the carrier tape are laminated so as to contact the one surface of the foam and the pressure-sensitive adhesive layer of the carrier tape. do.

It is preferable that the said foam member is used as objects for electrical and electronic devices.

Moreover, this invention provides the electrical/electronic device which has the said foam member.

In addition, the present invention provides a step of foam molding a resin composition containing a resin and a lubricant to obtain a sheet-like foam, and decomposing or moving the lubricant from one surface of the foam to a depth of 50 nm from the one surface in the thickness direction. The content of the lubricant in the above is 70% by weight or less of the content of the lubricant in the area from the cutting surface to a depth of 50 nm in the thickness direction when the foam is cut parallel to the surface of the foam so that the thickness is half. It provides a method for producing a foam, comprising the step of reducing.

Since the foam in the foam member of the present invention has the above structure, it is obtained with good moldability, has good pick-up properties (that is, the foam itself has good adhesion to the carrier tape), and can be peeled from the carrier tape. When foam breaks are difficult to occur, the selection range of such a carrier tape is wide. Furthermore, by this, the foam member of the present invention is held by the carrier tape and has excellent properties to the carrier tape such as workability and transportability, and the selection range of the usable carrier tape is wide.

Further, since the foam in the foam member of the present invention exhibits the above-described effects, it is not necessary to laminate different materials such as a resin layer for improving the pick-up property of the foam to the carrier tape on the foam, and the foam itself. There is no deterioration in the physical properties of In addition, since it is not necessary to laminate the different materials to the foam, the manufacturing process is simplified in this case.

BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic which shows an example of the foam of this invention.
2 is a schematic view showing an example of the foam member of the present invention.

The foam member of the present invention is a single sheet-like foam, and the lubricant content in the region from one surface of the foam to a depth of 50 nm in the thickness direction is cut parallel to the surface of the foam such that the foam is half the thickness. It has a foam which is 70 weight% or less of the lubricant content in the area|region from the cutting surface at the time of thickness direction to the depth of 50 nm. In addition, in this specification, the said foam may be called "the foam of this invention."

[foam]

The foam of the present invention is a single foam. Here, the "single foam" refers to a foam integrally molded by one foam molding, and does not include, for example, a foam obtained by combining a plurality of foams by lamination, adhesion, or the like.

The content of the lubricant in the region from one surface to a depth of 50 nm in the thickness direction of the foam of the present invention is 50 nm in the thickness direction from the cut surface when the foam of the present invention is cut parallel to the surface of the foam so that the thickness is half It is 70 weight% or less of the lubricant content in the area|region up to the depth of , Preferably it is 60 weight% or less, More preferably, it is 55 weight% or less, More preferably, it is 50 weight% or less. The lubricant content in the region from the cut surface to a depth of 50 nm in the thickness direction when the foam of the present invention is cut parallel to the surface of the foam to have a thickness of half represents the content of the lubricant inside the foam of the present invention, It is the content of the lubricant normally used to the extent that there is no problem in the moldability of the resin. When the content of the lubricant on one surface of the foam is 70% by weight or less of the content of the lubricant inside the foam, the adhesion on the surface of the foam is hardly inhibited by the lubricant, and the adhesion to the carrier tape of a wide range of adhesive strength is improved, and When peeling, a foam is hard to break.

In addition, in this specification, the said "region from one surface to a depth of 50 nm in the thickness direction" may be referred to as a "surface region". In addition, the said "region from the cutting surface to a depth of 50 nm in the thickness direction when the foam is cut parallel to the foam surface so that the thickness may be half" may be called an "internal region". Moreover, in the foam of this invention, the said surface area|region and the said internal area|region may have an overlapping area|region. In addition, if the foam is cut parallel to the surface of the foam so that the thickness is half, there will be two foams of the same thickness, and inner regions exist on both sides of the two foams, but the lubricant content in the surface area is, What is necessary is just to be 70 weight% or less with respect to the lubricant content of at least one inner area|region.

Although the ratio of the lubricant content in the surface region to the lubricant content in the inner region also varies depending on the lubricant used, for example, a compound used as a lubricant is analyzed by time-of-flight secondary ion mass spectrometry in each of the surface region and the inner region. (TOF-SIMS), it can calculate by comparing the detection amount in a surface area and an inner area|region. For example, when a nitrogen atom-containing compound is used as a lubricant, the amount of the nitrogen atom-containing compound in each of the surface region and the inner region is detected, and the amount of the nitrogen atom-containing compound is compared by comparing the detected amounts in the surface region and the inner region. A positive ratio can be computed and this can be made into the ratio of lubricant content.

The content of the lubricant in the region from the surface (the other surface) opposite to the one surface to the depth of 50 nm in the thickness direction of the foam of the present invention is not particularly limited, and the content of the lubricant in the inner region is 70 weight% or less may be sufficient, and the grade same as the lubricant content in the said internal area|region may be sufficient.

1, the schematic of an example of the foam of this invention is shown. 1 , a foam 1 of the present invention has one surface 11 and the other surface 12 . The surface region 13 is a region from the one surface 11 to a depth of 50 nm in the thickness direction. L is a cut surface when the foam 1 of this invention is cut parallel to the foam surface so that thickness may become half. The inner region 14 is a region from the cut surface L to a depth of 50 nm in the thickness direction. In addition, in FIG. 1, when the foam 1 of this invention is cut parallel to the foam surface so that the thickness may become half, it thickness direction from the said cut surface L on the foam side which does not have the surface area 13 Although the region up to a depth of 50 nm was defined as the inner region 14, the region from the cut surface L on the side of the foam having the surface region 13 to a depth of 50 nm in the thickness direction may be defined as the inner region.

The apparent density of the foam of the present invention is not particularly limited, 0.01 to 0.20g / cm ³ and more preferably 0.02 to 0.10g / cm ^3, more preferably 0.03 to 0.08g / cm ^3. When the said apparent density is 0.01 g/cm<^3> or more, when peeling from a carrier tape, it is more difficult to foam-break. In addition, when used for good shock absorption and electrical and electronic equipment, good sealing properties and good dustproof properties can be ensured. When the apparent density is 0.20 g/cm ³ or less, flexibility is improved, excellent shock absorption properties, and excellent clearance followability can be obtained when used in electrical and electronic devices.

Repulsive force at the time of 50% compression of the foam as defined in the present invention is not particularly limited, from 0.1 to 4.0N / cm ² it is preferable, and more preferably 0.2 to 3.5N / cm ^2, more preferably 0.3 to 3.0N/cm ² is. In addition, in this specification, the repulsive force at the time of 50% compression defined below may simply be called "repulsive force at the time of 50% compression."

Repulsive force at 50% compression: A large repulsion load when the foam is compressed to a thickness of 50% with respect to the initial thickness in the thickness direction under an atmosphere of 23°C

When the repulsive force at the time of 50% compression is 0.1 N/cm ² or more, moderate rigidity becomes easy to be obtained, and workability and workability are improved. When the repulsive force at the time of 50% compression is 4.0 N/cm ² or less, excellent flexibility is obtained.

Although the average cell diameter of the foam of this invention is not specifically limited, 10-200 micrometers is preferable, More preferably, it is 15-180 micrometers, More preferably, it is 20-150 micrometers, Especially preferably, it is 30-100 micrometers. . When the average cell diameter is 10 µm or more, flexibility is excellent. When the said average cell diameter is 200 micrometers or less, generation|occurrence|production of a pinhole and generation|occurrence|production of a coarse cell (void) is suppressed, and it becomes easy to obtain the outstanding dustproof property and the outstanding light-shielding property.

In particular, the foam of the present invention preferably has an apparent density of 0.01 to 0.20 g/cm ³ , a repulsive force at 50% compression of 0.1 to 4.0 N/cm ² , and an average cell diameter of 10 to 200 μm. In this case, it is obtained with good moldability, has good pick-up properties, and when it is peeled from the carrier tape, foam breakage is unlikely to occur. The strength is excellent. Moreover, in this case, since it is easy to change the foam of this invention into various shapes, it can utilize for various processed goods and a processing process. In addition, since the amount of gas (mainly air) present inside the foam increases and the insulation is excellent, by using it in the vicinity of an electronic component, it is possible to make it difficult to cause destruction by charging. Moreover, since it is excellent also in heat insulation, by using it inside an electronic device, the internal temperature can be maintained uniformly also to a sudden external temperature change, and the performance of an electronic device can be stabilized.

Although the maximum cell diameter of the foam of this invention is not specifically limited, Less than 200 micrometers is preferable, More preferably, it is 190 micrometers or less, More preferably, it is 175 micrometers or less. When the maximum cell diameter is less than 200 μm, the cell structure is excellent without coarse cells, and thus the occurrence of a problem that dust enters from the coarse cells and deteriorates dust resistance can be suppressed, and excellent sealing properties and It becomes easy to obtain dustproofness. Moreover, it becomes easy to obtain the outstanding light-shielding property.

The cell diameter of the foam of this invention is calculated|required by introduce|transducing the enlarged image of the cell structure part of a cut surface with a digital microscope, calculating|requiring the area of a cell, and calculating|requiring the area of a circle by image analysis, for example.

Although the thickness of the foam of this invention is not specifically limited, 0.05-5.0 mm is preferable, More preferably, it is 0.06-3.0 mm, More preferably, it is 0.07-1.5 mm, Especially preferably, it is 0.08-1.0 mm.

The one surface of the foam of the present invention and the adhesive surface of the pressure-sensitive adhesive sheet having an adhesive force to the SUS plate (temperature: 23±2°C, humidity: 50±5RH%, tensile rate: 0.3m/min) of 0.15N/20mm The peeling force (temperature: 23±2°C, humidity: 50±5RH%, tensile rate: 0.3 m/min) when bonding and peeling the foam of the present invention from the pressure-sensitive adhesive sheet is not particularly limited, but 0.10 N/min 20 mm or more (for example, 0.10-2.00N/20mm) is preferable, More preferably, it is 0.15-1.00N/20mm, More preferably, it is 0.20-0.80N/20mm. When the said peeling force is 0.10 N/20mm or more, the adhesive force with respect to a non-adhesive carrier tape is sufficient, and the selection range of the carrier tape with favorable pick-up property becomes wider. When the peeling force is 2.00 N/20 mm or less, the selection range of the carrier tape in which foam breakage does not easily occur becomes wider.

The one surface of the foam of the present invention and the adhesive surface of the pressure-sensitive adhesive sheet having an adhesive force to the SUS plate (temperature: 23±2°C, humidity: 50±5RH%, tensile rate: 0.3m/min) of 0.35N/20mm The peeling force (temperature: 23±2°C, humidity: 50±5RH%, tensile rate: 0.3 m/min) when bonding and peeling the foam of the present invention from the pressure-sensitive adhesive sheet is not particularly limited, but 0.10 N/min 20 mm or more (for example, 0.10-2.00N/20mm) is preferable, More preferably, it is 0.15-1.00N/20mm, More preferably, it is 0.20-0.80N/20mm. When the said peeling force is 0.10 N/20 mm or more, the adhesive force with respect to a weakly adhesive carrier tape is enough, and the selection range of the carrier tape with favorable pick-up property becomes wider. When the peeling force is 2.00 N/20 mm or less, the selection range of the carrier tape in which foam breakage does not easily occur becomes wider.

The foam of the present invention has a cell structure (cell structure). The cell structure (cell structure) in the foam of the present invention is not particularly limited, but from the viewpoint of obtaining excellent flexibility, a semi-continuous semi-closed cell structure (a cell structure in which an closed cell structure and an open cell structure are mixed, and the ratio thereof is not particularly limited) is preferred. In particular, it is preferable that the foam of the present invention has a cell structure in which the closed cell structure portion is 40% or less (more preferably 30% or less).

It is preferable that the foam of this invention contains resin. As said resin, a thermoplastic resin is preferable. Only 1 type may be used for the said resin, and 2 or more types may be used for it.

Examples of the thermoplastic resin include polyolefin resin, styrene resin, polyamide resin, polyamideimide, polyurethane, polyimide, polyetherimide, acrylic resin, polyvinyl chloride, polyvinyl fluoride, alkenyl aromatic resin. , polyester resin, polycarbonate, polyacetal, polyphenylene sulfide, and the like.

A homopolymer (homopolymer) may be sufficient as the said polyolefin resin, and the copolymer (copolymer) containing 2 or more types of monomers may be sufficient as it. Moreover, when the said polyolefin resin is a copolymer, a random copolymer or a block copolymer may be sufficient. Only 1 type may be used for the said polyolefin resin, and 2 or more types may be used for it.

The polyolefin-based resin is not particularly limited, but is a polymer composed (formed) of α-olefin as an essential monomer component, that is, a polymer having at least a structural unit derived from α-olefin in a molecule (in one molecule). it is preferable The polyolefin-based resin may be, for example, a polymer composed of only α-olefin, or a polymer composed of α-olefin and monomer components other than α-olefin.

Examples of the α-olefin include an α-olefin having 2 to 8 carbon atoms (eg, ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, etc.). As for the said alpha-olefin, only 1 type may be used and 2 or more types may be used for it.

Examples of the monomer component other than the α-olefin include ethylenically unsaturated monomers such as vinyl acetate, acrylic acid, acrylic acid ester, methacrylic acid, methacrylic acid ester, and vinyl alcohol. Only 1 type may be used for monomer components other than the said alpha-olefin, and 2 or more types may be used for it.

Examples of the polyolefin-based resin include low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, polypropylene (propylene homopolymer), ethylene and propylene copolymer, ethylene and α-olefin other than ethylene copolymer; and a copolymer of propylene and an ?-olefin other than propylene, a copolymer of ethylene and propylene, and an ?-olefin other than ethylene and propylene, and a copolymer of propylene and an ethylenically unsaturated monomer.

Although the said polyolefin-type resin is not specifically limited, It is preferable that it is a linear polyolefin from the point from which a polyolefin-type resin foam with a high expansion ratio is obtained.

The polyolefin-based resin is preferably a polymer (polypropylene-based resin) composed of propylene as an essential monomer component from the viewpoint of heat resistance, that is, a polymer having at least a structural unit derived from propylene. Examples of the polypropylene-based resin include polypropylene (propylene homopolymer), a copolymer of ethylene and propylene, and a copolymer of propylene and α-olefin other than propylene. Only 1 type may be used for alpha-olefin other than the said propylene, and 2 or more types may be used for it.

The content of α-olefin in the polyolefin-based resin is not particularly limited, but is preferably 0.1 to 10% by weight, more preferably 1 to 10% by weight, based on the total amount (100% by weight) of the monomer components constituting the polyolefin-based resin. 5% by weight.

Examples of the polyester resin include polyalkylene terephthalate resins such as polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, and polycyclohexane terephthalate. can be heard Moreover, the copolymer which copolymerized 2 or more types of said polyalkylene terephthalate-type resin is also mentioned. The copolymer may be a copolymer in any form of a random copolymer, a block copolymer, and a graft copolymer.

As said thermoplastic resin, in addition to this, elastomer components, such as rubber|gum and a thermoplastic elastomer, are mentioned. When an elastomer component is contained, the elasticity of a foam improves and it is easy to improve shock absorption.

Examples of the rubber include natural or synthetic rubbers such as natural rubber, polyisobutylene, isoprene rubber, chloroprene rubber, butyl rubber and nitrile butyl rubber. As for the said rubber, only 1 type may be used and 2 or more types may be used for it.

Examples of the thermoplastic elastomer include thermoplastic olefins such as ethylene-propylene copolymer elastomer, ethylene-propylene-diene copolymer elastomer, ethylene-vinyl acetate copolymer elastomer, polybutene elastomer, polyisobutylene elastomer, and chlorinated polyethylene elastomer. elastomer; thermoplastic styrene elastomers such as styrene-butadiene-styrene copolymer elastomer, styrene-isoprene-styrene copolymer elastomer, styrene-isoprene-butadiene-styrene copolymer elastomer, and hydrogenated products thereof; thermoplastic polyester-based elastomers; thermoplastic polyurethane-based elastomers; A thermoplastic acrylic elastomer etc. are mentioned. As for the said thermoplastic elastomer, only 1 type may be used and 2 or more types may be used for it.

As said resin, especially, a thermoplastic resin is preferable, More preferably, they are a polyolefin resin and polyester resin (especially thermoplastic polyester-type elastomer). When a polyester-based resin is used, it is easy to suppress the occurrence of breakage or breakage when fine width processing (eg, processing to a line width of about 1 mm, etc.) is performed. Moreover, it is excellent in shape-retaining property, and is preferable for foam sealing materials. Polyester-type resin has high strength and a high modulus of elasticity among thermoplastic resins.

Although it does not specifically limit as said thermoplastic polyester-type elastomer, A polyester-type thermoplastic elastomer containing aromatic dicarboxylic acid and diol as monomer units is preferable. As for the said thermoplastic polyester type elastomer, only 1 type may be used and 2 or more types may be used for it.

Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, phthalic acid, naphthalenecarboxylic acid (eg, 2,6-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, etc.), di Phenyl ether dicarboxylic acid, 4,4'- biphenyl dicarboxylic acid, etc. are mentioned. Only 1 type may be used for the said aromatic dicarboxylic acid, and 2 or more types may be used for it.

Examples of the diol include ethylene glycol, propylene glycol, trimethylene glycol, 1,4-butanediol (tetramethylene glycol), 2-methyl-1,3-propanediol, 1,5-pentanediol, 2,2- Dimethyl-1,3-propanediol (neopentyl glycol), 1,6-hexanediol, 3-methyl-1,5-pentanediol, 2-methyl-2,4-pentanediol, 1,7-heptanediol, 2,2-diethyl-1,3-propanediol, 2-methyl-2-propyl-1,3-propanediol, 2-methyl-1,6-hexanediol, 1,8-octanediol, 2-butyl -2-ethyl-1,3-propanediol, 1,3,5-trimethyl-1,3-pentanediol, 1,9-nonanediol, 2,4-diethyl-1,5-pentanediol, 2- aliphatic diols such as methyl-1,8-octanediol, 1,10-decanediol, 2-methyl-1,9-nonanediol, 1,18-octadecanediol and dimer diol; 1,4-cyclohexanediol, 1,3-cyclohexanediol, 1,2-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,2-cyclohexanedimethanol alicyclic diols such as; Aromatic diols, such as an ethylene oxide adduct of bisphenol A and bisphenol A, bisphenol S, an ethylene oxide adduct of bisphenol S, xylylenediol, and naphthalenediol; Ether glycol, such as diethylene glycol, triethylene glycol, tetraethylene glycol, polyethyleneglycol, and dipropylene glycol, etc. are mentioned. Moreover, as diol, the diol component in the form of a polymer, such as polyetherdiol and polyesterdiol, may be sufficient. Examples of the polyether diol include polyethylene glycol, polypropylene glycol, polytetramethylene glycol obtained by ring-opening polymerization of ethylene oxide, propylene oxide, tetrahydrofuran, and the like, and copolyethers copolymerized with these. As for the said diol, only 1 type may be used and 2 or more types may be used for it.

Moreover, especially as said thermoplastic polyester-type elastomer, the polyester-type elastomer which is a block copolymer of a hard segment and a soft segment is preferable. In this case, since the elastic modulus is large and it is excellent in flexibility, the repulsive force at the time of 50% compression becomes in a preferable range, and it is excellent also in shock absorption.

Although it does not specifically limit as a polyester-type thermoplastic elastomer which is a block copolymer of a hard segment and a soft segment, The following (i) - (iii) are preferable, More preferably, the polyester/polyether type copolymer of the following (ii) am.

(i) a polyester using, as a monomer unit, an aromatic dicarboxylic acid and a diol having 2 to 4 carbon atoms in the main chain between the two hydroxyl groups as a hard segment, the aromatic dicarboxylic acid and the carbon number in the main chain between the two hydroxyl groups A polyester/polyester type copolymer comprising, as a soft segment, polyester using a diol having a value of 5 or more as a monomer unit.

(ii) A polyester/polyether-type copolymer using the same polyester as in (i) as a hard segment and using polyethers such as polyetherdiol and aliphatic polyether as a soft segment

(iii) A polyester/polyester type copolymer comprising the same polyester as in (i) as a hard segment and an aliphatic polyester as a soft segment

Moreover, it is also preferable to use together polyolefin resin and the said elastomer component as said resin. When an elastomer component is added to a polyolefin resin, the elasticity of a foam improves and it is easy to improve shock absorption.

As the elastomer component when used in combination with a polyolefin-based resin, among them, a thermoplastic olefin-based elastomer is preferable, and particularly preferably, an olefin-based elastomer having a structure in which the polyolefin-based resin component and the olefin-based rubber component are microphase-separated. As the olefin-based elastomer having a structure in which the polyolefin-based resin component and the olefin-based rubber component are micro phase-separated, an elastomer comprising polypropylene (PP) and ethylene-propylene rubber (EPM) or ethylene-propylene-diene rubber (EPDM) is desirable. However, the polyolefin-based resin component in the olefin-based elastomer having a microphase dispersed structure is included in the elastomer component. The weight ratio of the polyolefin-based resin component and the olefin-based rubber component is preferably, from the viewpoint of compatibility, polyolefin-based resin component/olefin-based rubber component = 90/10 to 10/90, more preferably 80/20 to 20 /80.

Although the melt flow rate (MFR) in 230 degreeC of the said resin is not specifically limited, 1.5-4.0 g/10min is preferable, More preferably, it is 1.5-3.8 g/10min, More preferably, 1.5-3.5 g/ 10 min. The moldability of a resin composition improves that the said MFR is 1.5 g/10min or more. For example, it is difficult to clog from the extruder and can be easily extruded into a desired shape. When the MFR is 4.0 g/10 min or less, fluctuations in cell diameter after formation of the cell structure are less likely to occur, and a uniform cell structure is easily obtained. In addition, in this specification, MFR in 230 degreeC shall say MFR measured at the temperature of 230 degreeC, and load 2.16kgf based on ISO1133 (JIS K7210).

Although content of the said resin in the foam of this invention is not specifically limited, 70 weight% or more is preferable with respect to the weight (100 weight%) of a foam, More preferably, it is 80 weight% or more, More preferably, it is 90 weight%. % or more. Although the upper limit of the said content is not specifically limited, Less than 100 weight% may be sufficient.

When the said resin contains the said polyolefin resin, content of polyolefin resin is although it does not specifically limit, 10 weight% or more is preferable with respect to the weight (100 weight%) of a foam, More preferably, 20 weight% More preferably, it is 30 weight% or more. Although the upper limit of the said content is not specifically limited, Less than 100 weight% may be sufficient, Preferably it is 80 weight% or less, More preferably, it is 50 weight% or less.

When the resin contains the polyolefin-based resin and the elastomer component, the content of the elastomer component is not particularly limited, but it is preferably more than 0% by weight and not more than 70% by weight with respect to the weight (100% by weight) of the foam. and more preferably 20 to 60% by weight, and still more preferably 20 to 50% by weight.

The foam of the present invention contains a lubricant as described above. By including the lubricant, the moldability of the resin composition for molding the foam of the present invention is improved. Specifically, the slidability of the resin composition is improved, for example, in the case of extrusion molding, it becomes easy to extrude into a desired shape without clogging from the extruder, and in the case of batch molding, the fluidity of the resin composition is improved, It becomes easy to develop a resin composition to every corner of a metal mold|die, and to give a smooth surface. Only 1 type may be used for the said lubricant, and 2 or more types may be used for it.

As the lubricant, a known or customary lubricant used for foam molding can be used. Examples of the lubricant include hydrocarbon lubricants such as liquid paraffin, paraffin wax, microwax, and polyethylene wax; fatty acid-based lubricants such as stearic acid, behenic acid, and 12-hydroxystearic acid; higher alcohol lubricants such as stearyl alcohol; fatty acid carboxylic acids and derivatives thereof; fatty acid amide lubricants such as stearic acid amide, oleic acid amide, and erucic acid amide; alkylene fatty acid amide lubricants such as methylenebisstearic acid amide and ethylenebisstearic acid amide; ester lubricants such as butyl stearate, monoglyceride stearate, pentaerythritol tetrastearate, hydrogenated castor oil, and stearyl stearate; An acrylic lubricant etc. are mentioned.

Examples of the derivative of the aliphatic carboxylic acid include an aliphatic carboxylic acid anhydride, an alkali metal salt of an aliphatic carboxylic acid, and an alkaline earth metal salt of an aliphatic carboxylic acid. As said aliphatic carboxylic acid and its derivative(s), C3-C30 fatty acid carboxylic acid, such as lauric acid, stearic acid, crotonic acid, oleic acid, maleic acid, glutanoic acid, behenic acid, and montanic acid, and its derivative(s), among them. is preferable In addition, among the fatty acid carboxylic acids and derivatives thereof having 3 to 30 carbon atoms, stearic acid and its derivatives, montanic acid and its derivatives are preferable from the viewpoint of dispersibility, solubility, and the effect of improving the surface appearance to the resin composition, In particular, alkali metal salts of stearic acid and alkaline earth metal salts of stearic acid are preferable. Moreover, zinc stearate and a calcium stearate are more preferable among the alkali metal salt of stearic acid and the alkaline-earth metal salt of stearic acid.

In addition, it is preferable to use at least a nitrogen atom-containing compound as the lubricant. In this case, since it becomes possible to calculate the ratio of the lubricant content by measuring the amount of the nitrogen atom-containing compound in each of the surface area and the inner area of the foam of the present invention, the ratio of the lubricant content between the surface area and the inner area is calculated it becomes easier to do Therefore, as said lubricating agent, a fatty-acid amide type lubricating agent is especially preferable. Since the fatty acid amide-based lubricant does not easily migrate from the inner region to the surface region, it is useful for making the ratio of the lubricant content in the surface region smaller. In addition, since it is difficult to move the lubricant inside the foam and it is difficult to precipitate the lubricant on the surface of the foam, it is difficult to change the properties of many types of pressure-sensitive adhesive layers to be bonded, and it is also advantageous to expand the options of the pressure-sensitive adhesive layer that can be used are being prepared

For this reason, the content of the nitrogen atom-containing compound in the surface region of the foam of the present invention is not particularly limited, but is preferably 70% by weight or less of the content of the nitrogen atom-containing compound in the inner region, more preferably It is 60 weight% or less, More preferably, it is 55 weight% or less, Especially preferably, it is 50 weight% or less.

Although the content of the lubricant in the internal region of the foam of the present invention is not particularly limited, it is preferably 0.1 to 20 parts by weight, more preferably 0.3 to 10 parts by weight, still more preferably relative to 100 parts by weight of the resin in the same region. is 0.5 to 8 parts by weight. When content of the said lubricant is 0.1 weight part or more, the effect obtained by including the said lubricant becomes easy to be acquired. When content of the said lubricant is 20 weight part or less, bubble omission at the time of foaming a resin composition is suppressed, and high foaming becomes easy. In addition, content in the said internal area|region shall be the same as content in the resin composition which forms a foam.

The foam of this invention may contain the additive other than each said component in the range which does not impair the effect of this invention. Examples of the additive include a softener, a crosslinking agent, a rust inhibitor, an antiaging agent, a weathering agent, an ultraviolet absorber, a dispersant, a plasticizer, a colorant (pigment, dye, etc.), an antistatic agent, a surfactant, a tension modifier, a flow modifier, an antioxidant, a filler. , a reinforcing agent, a surface treatment agent, a shrinkage inhibitor, a vulcanizing agent, a flame retardant, and the like. As for the said additive, only 1 type may be used and 2 or more types may be used for it.

When the said resin contains a polyolefin resin, it is preferable that the foam of this invention contains a softening agent further. In particular, it is preferable to contain an emollient together with the elastomer component. When a softener is contained, the processability and flexibility of a foam can be improved. Only 1 type may be used for the said softening agent, and 2 or more types may be used for it.

It does not specifically limit as said softener, The softener generally used for rubber products is mentioned. Specific examples of the softener include mineral oils such as paraffinic, naphthenic and aromatic; petroleum-based substances such as process oil, lubricating oil, liquid paraffin, petroleum asphalt, and petrolatum; coal tars such as coal tar and coal tar pitch; fatty oils such as castor oil, linseed oil, rapeseed oil, soybean oil, and palm oil; waxes such as tall oil, beeswax, carnauba wax, and lanolin; synthetic high molecular substances such as petroleum resin, coumaron indene resin, and atactic polypropylene; ester compounds such as dioctyl phthalate, dioctyl adipate and dioctyl sebacate; and microcrystalline wax, sub(Pactis), liquid polybutadiene, modified liquid polybutadiene, liquid thiochol, liquid polyisoprene, liquid polybutene, liquid ethylene/α-olefin copolymer, and the like. Among them, mineral oil, liquid polyisoprene, liquid polybutene, and liquid ethylene/α-olefin copolymer are preferable, and liquid polyisoprene, liquid polybutene, and liquid ethylene/α-olefin copolymer are more preferable.

When the foam of the present invention contains a softening agent, the content of the softening agent in the foam is not particularly limited, but is preferably from 1 to 200 parts by weight, more preferably from 5 to 100 parts by weight, more preferably from 1 to 200 parts by weight with respect to 100 parts by weight of the resin. Preferably it is 10-50 weight part. When the content is 1 part by weight or more, the workability and flexibility of the foam tend to improve. When the content is 100 parts by weight or less, dispersibility with resin tends to improve.

When the foam of the present invention contains a softening agent together with the elastomer component, the content of the softening agent in the foam is not particularly limited, but is preferably from 1 to 200 parts by weight, more preferably from 5 to 200 parts by weight based on 100 parts by weight of the elastomer component. 100 parts by weight, more preferably 10 to 50 parts by weight. When the content is 1 part by weight or more, the workability and flexibility of the foam tend to improve. When the content is 100 parts by weight or less, the dispersibility tends to be improved during kneading with the elastomer component.

In addition, in the present specification, the content of each component (eg, resin, lubricant, additive, etc.) contained in the foam of the present invention may be appropriately selected from within the range described so that the total is 100% by weight or less. have.

The shape of the foam of the present invention is sheet-like (tape-like). In addition, depending on the purpose of use, it may be processed into an appropriate shape. For example, it may be processed into a linear shape, a circular shape, a polygonal shape, a frame shape (frame shape), etc. by a cutting process, a punching process, etc.

(Method for producing the foam of the present invention)

The foam of the present invention comprises a step of foam molding a resin composition containing a resin and a lubricant to obtain a foam (foam molding step), and decomposing or moving the lubricant from one surface of the foam, and 50 nm in the thickness direction from the one surface. The lubricant content in the region to the depth is 70% by weight or less of the lubricant content in the region from the cutting surface to the depth of 50 nm in the thickness direction when the foam is cut parallel to the foam surface so that the thickness is half It can manufacture by the method including the process (lubricant reduction process) of reducing so that it becomes possible. In addition, in this specification, the method of manufacturing the said foam of this invention may be called "the manufacturing method of the foam of this invention."

The said resin composition may contain the said additive etc. as needed. The resin composition may further contain a bubble nucleating agent (foam nucleating agent) and a crystal nucleating agent. Especially, it is preferable that the said resin composition contains a bubble nucleating agent. When a bubble nucleating agent is included, the foam which has a uniform and fine cell structure is easy to be obtained by foaming the said resin composition.

As said bubble nucleating agent, particle|grains are mentioned, for example. Examples of the particles include clays such as talc, silica, alumina, zeolite, calcium carbonate, magnesium carbonate, barium sulfate, zinc oxide, titanium oxide, aluminum hydroxide, magnesium hydroxide, mica, montmorillonite, carbon particles, glass fibers, carbon tube etc. are mentioned. Only 1 type may be used for the said bubble nucleating agent, and 2 or more types may be used for it. In particular, clay, such as magnesium hydroxide and montmorillonite, is preferable because it can provide flame retardance to the foam obtained.

Although the average particle diameter (particle diameter) of the particle|grains as said bubble nucleating agent is not specifically limited, 0.1-20 micrometers is preferable. There exists a tendency for the function as a bubble nucleating agent to exhibit more fully that the said average particle diameter is 0.1 micrometer or more. When the said average particle diameter is 20 micrometers or less, there exists a tendency for gas escape more difficult at the time of foam molding.

When the said resin composition contains a bubble nucleating agent, content of the bubble nucleating agent in a resin composition is although it does not specifically limit, 0.5-125 weight part is preferable with respect to 100 weight part of resin, More preferably, it is 1-120 weight part. .

The said resin composition can be produced by kneading the said resin, the said lubricating agent, the said bubble nucleating agent, the said additive, etc. as needed. For example, the said resin composition can be obtained by kneading|mixing with well-known melt-kneading extrusion apparatuses, such as a single-screw (single-screw) kneading extruder and a twin-screw kneading extruder, and extruding.

In the case of using the elastomer component and the softener, the elastomer component and the softener may be mixed in advance (a mixture of the elastomer component and the softener) with another resin component or the like. The content of the softening agent in the mixture of the elastomer component and the softener is not particularly limited, but is preferably from 1 to 200 parts by weight, more preferably from 1 to 200 parts by weight based on 100 parts by weight of the resin component (eg, polyolefin resin component) in the elastomer component. Preferably 5 to 100 parts by weight, more preferably 10 to 50 parts by weight. Moreover, when the content of the softening agent is 200 parts by weight or less, the dispersibility tends to be more favorable at the time of kneading with the elastomer component.

The mixture of the elastomer component and the softener may contain the above additives (especially anti-aging agents, weathering agents, ultraviolet absorbers, dispersants, plasticizers, colorants, antistatic agents, surfactants, tension modifiers, and flow modifiers).

The content of the additive in the mixture of the elastomer component and the softener is not particularly limited, but is preferably 0.01 to 100 parts by weight, more preferably 0.01 to 100 parts by weight, based on 100 parts by weight of the resin component (eg, polyolefin resin component) in the elastomer component. is 0.05 to 50 parts by weight, more preferably 0.1 to 30 parts by weight. Moreover, it will become easier to express the effect by adding an additive as the said content is 0.01 weight part or more.

The melt flow rate (MFR) (230°C) of the mixture of the elastomer component and the softener is not particularly limited, but from the viewpoint of obtaining good moldability, 3 to 10 g/10 min is preferable, and more preferably 4 to 9 g/10 min. am.

Although "JIS A hardness" in the mixture of the said elastomer component and a softener is not specifically limited, 30-90 degrees is preferable, More preferably, it is 40-85 degrees. When the said "JIS A hardness" is 30 degrees or more, the foam of a high foaming ratio is easy to be obtained. Moreover, if the said "JIS A hardness" is 90 degrees or less, a flexible foam will be easy to be obtained. In addition, "JIS A hardness" in this specification shall mean the hardness measured based on ISO7619 (JIS K6253).

Examples of the resin composition include a strand type, a sheet type, a flat plate type, and a pellet type (for example, a pellet type obtained by water cooling or air cooling of a resin composition extruded into a strand type, and cutting to an appropriate length). Especially, a pellet type is preferable from a viewpoint of productivity.

In the foam molding step, as a method of foaming the resin composition, a physical foaming method and a chemical foaming method are exemplified. The physical foaming method is a method of forming cells (bubbles) by impregnating (dispersing) a resin composition with a low boiling point liquid (foaming agent), and then volatilizing the foaming agent. Moreover, the said chemical foaming method is a method of forming a cell with the gas generated by the thermal decomposition of the compound added to the resin composition. Among them, the physical foaming method is preferable, and the physical foaming method using a high-pressure gas as the foaming agent is more preferable from the viewpoint of avoiding contamination of the foam and easiness of obtaining a fine and uniform cell structure.

Although it does not specifically limit as said foaming agent used in the physical foaming method, From a viewpoint of being easy to obtain a fine cell-density cell structure, a gas is preferable, In particular, the resin constituting the foam (the resin composition contains A gas (inert gas) that is inert to the resin) is preferable.

Examples of the inert gas include carbon dioxide, nitrogen gas, air, helium, and argon. In particular, carbon dioxide is preferable because the inert gas has a large amount of impregnation into the resin composition and the impregnation rate is high. Only 1 type may be used for the said inert gas, and 2 or more types may be used for it.

Although the mixing amount (content, impregnation amount) of the said foaming agent is not specifically limited, 2 to 10 weight% is preferable with respect to the total weight (100 weight%) of the said resin composition.

The inert gas is preferably in a supercritical state at the time of impregnation from the viewpoint of speeding up the impregnation rate with respect to the resin composition. That is, in the foam molding step, the foam is preferably formed by foaming the resin composition using a supercritical fluid. When the inert gas is a supercritical fluid (supercritical state), solubility in the resin composition is increased, and high concentration impregnation (incorporation) is possible. In addition, since it is possible to impregnate at a high concentration, when the pressure is sharply lowered after impregnation, the generation of bubble nuclei increases, and the density and porosity of the bubbles generated by the growth of the bubble nuclei are increased. can be obtained In addition, the critical temperature of carbon dioxide is 31 DEG C, and the critical pressure is 7.4 MPa.

As a physical foaming method using a gas as a foaming agent, the resin composition is impregnated with a high-pressure gas (eg, an inert gas, etc.) and then foamed through a step of depressurizing (for example, to atmospheric pressure) (step of releasing the pressure). The method of forming by making it is preferable. Specifically, a method of forming an unexpanded molding by molding a resin composition, impregnating the unexpanded molding with a high-pressure gas, and then foaming through a step of reducing the pressure (for example, to atmospheric pressure), or a molten resin composition A gas (for example, an inert gas, etc.) is impregnated with a gas (for example, an inert gas, etc.) under a pressurized state, followed by foaming under reduced pressure (for example, up to atmospheric pressure), and a method for forming by molding.

That is, in the case of forming a foam in the foam molding process, the resin composition is molded into an appropriate shape such as a sheet shape to obtain an unfoamed resin molded article (non-foamed molded article), and then a high-pressure gas is supplied to the unfoamed resin molded article. It may be impregnated and foamed by releasing the pressure (batch method), and the resin composition is kneaded with a high-pressure gas under high-pressure conditions, and the pressure is released at the same time as molding, and molding and foaming are performed at the same time. You may carry out in a system (continuous system).

In the said arrangement|positioning method, the method of forming an unfoamed resin molded object, For example, the method of shape|molding a resin composition using extruders, such as a single screw extruder and a twin screw extruder; a method in which the resin composition is uniformly kneaded using a kneader equipped with blades such as rollers, cams, kneaders, and Banbury type, and press-molded to a predetermined thickness using a hot plate press or the like; The method of shape|molding a resin composition using an injection molding machine, etc. are mentioned. Moreover, the shape of an unfoamed resin molded object is a sheet shape, a roll shape, a plate shape, etc. are mentioned, for example. In the above arrangement method, the resin composition is molded by an appropriate method in which an unfoamed resin molded article having a desired shape or thickness is obtained.

In the above arrangement method, the unfoamed resin molded body is placed in a pressure-resistant container, high-pressure gas is injected (introduced, mixed) to impregnate the gas into the non-foamed resin molded body, and the pressure is released when the gas is sufficiently impregnated. (Usually to atmospheric pressure), a bubble structure is formed through the pressure reduction process of generating bubble nuclei in a resin composition.

In the continuous method, high-pressure gas is injected (introduced, mixed) while the resin composition is kneaded using an extruder (eg, single-screw extruder, twin-screw extruder, etc.) or an injection molding machine, and the high-pressure gas is sufficiently impregnated into the resin composition. By extruding the resin composition through a kneading and impregnating step, such as a die installed at the tip of the extruder, the pressure is released (usually up to atmospheric pressure), and the resin composition is foam-molded by a molding pressure reduction step of simultaneously molding and foaming.

In the batch system or the continuous system, a heating step of growing bubble nuclei by heating may be provided as needed. Moreover, you may make a bubble nucleus grow at room temperature without providing a heating process. Moreover, after growing a bubble, if necessary, it may cool rapidly with cold water etc., and you may fix the shape. The high-pressure gas introduction may be performed continuously or discontinuously. In addition, the heating method at the time of making a bubble nucleus grow is although it does not specifically limit, Well-known thru|or usual methods, such as a water bath, an oil bath, a hot roll, a hot-air oven, a far infrared ray, a near infrared ray, a microwave, are mentioned.

In the batch type gas impregnation step or the continuous kneading impregnation step, the pressure for impregnating the gas is appropriately selected in consideration of the type and operability of the gas, for example, 5 MPa or more (for example, 5-100 MPa) is preferable, More preferably, it is 7 MPa or more (for example, 7-100 MPa). That is, it is preferable to impregnate the resin composition with a gas having a pressure of 5 MPa or more (eg, a pressure of 5 to 100 MPa), and it is more preferable to impregnate an inert gas having a pressure of 7 MPa or more (eg, a pressure of 7 to 100 MPa). desirable. When the pressure of the gas is 5 MPa or more, bubble growth at the time of foaming can be appropriately suppressed, and there exists a tendency which can suppress that a cell becomes large too much. This is because, when the pressure is high, the amount of gas impregnated is relatively large compared to the time of low pressure, and the number of bubble nuclei formed at a rapid rate of bubble nucleation increases. depends on Moreover, in the pressure region of 5 MPa or more, even if the impregnation pressure is slightly changed, the cell diameter and the cell density do not change significantly, and the control of the cell diameter and the cell density becomes easy.

In addition, in the gas impregnation process in the batch system or the kneading impregnation process in the continuous system, the temperature (impregnation temperature) at the time of impregnating the gas varies depending on the type of gas or resin used, and is within a wide range. Although it can be selected, when operability etc. are considered, 10-350 degreeC is preferable. More specifically, as for the impregnation temperature in a batch system, 10-250 degreeC is preferable, More preferably, it is 40-240 degreeC, More preferably, it is 60-230 degreeC. Moreover, in a continuous system, 60-350 degreeC of impregnation temperature is preferable, More preferably, it is 100-320 degreeC, More preferably, it is 150-300 degreeC. In addition, when carbon dioxide is used as the high-pressure gas, in order to maintain a supercritical state, it is preferable that the temperature at the time of impregnation (impregnation temperature) is 32 degreeC or more (particularly 40 degreeC or more). In addition, after impregnating with gas, before foam-molding, you may cool the resin composition impregnated with gas to the temperature suitable for foam-molding (for example, 150-190 degreeC).

Further, in the batch system or the continuous system, the pressure reduction rate in the pressure reduction step (step of releasing pressure) is not particularly limited, but from the viewpoint of obtaining a cell structure having uniform and fine cells, preferably 5 to 300 MPa/sec.

In order to grow bubble nuclei, when providing a heating process, 40-250 degreeC is preferable, for example, as for heating temperature, More preferably, it is 60-250 degreeC.

In addition, the cell structure, density, and relative density of the foam of the present invention depend on the type of resin constituting the foaming method and the foaming conditions (for example, the type and amount of the foaming agent, the foaming) when foaming the resin composition. temperature, pressure, time, etc.)

Before sending the foam obtained at the said foaming molding process to the said lubricant reduction process, you may send it to other processes, such as a slice processing process and a hot-melting treatment process.

When the manufacturing method of the foam of this invention includes a slicing process, slicing is given to the foam obtained by the foam molding process. After foaming the said resin composition specifically, and obtaining a foam, the surface of the both surfaces of this foam is made to slice process. The foam has, in the vicinity of the surface, a layered portion having a higher density compared to the inside (layered portion having a lower expansion ratio compared to the inside, a skin layer) in many cases. According to the slicing process, this layered part can be removed, the cell structure inside can be exposed on the foam surface, and an opening part can be formed. Moreover, the improvement of thickness precision can be aimed at by a slicing process, and thickness precision improves by this.

When the manufacturing method of the foam of this invention includes a heat-melting treatment process, the surface of the obtained foam is further subjected to a heat-melting treatment (surface heat-melting treatment). Specifically, after foaming the resin composition to obtain a foam (after slicing if necessary), the surface of the foam is subjected to a heat melting treatment. In this way, by melting the surface in the thickness direction, the tensile strength in the longitudinal direction is increased to minimize the decrease in flexibility while suppressing the occurrence of breakage or breakage, and a foam can be easily and continuously obtained. Further, by returning the foamed portion to the non-foaming state (bulk), the surface roughness (error in thickness) is reduced and the thickness accuracy is improved.

As said heat-melting process, the press process by a hot roll, a laser irradiation process, the contact melt process on a heated roll, a frame process, etc. are mentioned, for example. In the case of press processing with a hot roll, the process can be performed using a thermal laminator or the like. Moreover, as a material of a roll, rubber, a metal, a fluororesin (For example, Teflon (trademark)), etc. are mentioned.

The temperature at the time of the thermal melting treatment is not particularly limited, but at least 15°C lower than the softening point or melting point of the resin contained in the foam (more preferably at least 12°C lower than the softening point or melting point of the resin contained in the foam) Preferably, the temperature is 20 ° C. or less higher than the softening point or melting point of the resin contained in the foam (more preferably, the temperature is 10 ° C or less higher than the softening point or melting point of the resin contained in the foam). If the temperature at the time of the thermal melting treatment is at least 15°C lower than the softening point or melting point of the constituting resin, it is preferable from the viewpoint of efficiently performing the thermal melting treatment. And sufficient heat-melting process can be performed and there exists a tendency for the thickness precision of a foam to improve more. Moreover, when the temperature at the time of a heat-melting process is a temperature 20 degrees C or less higher than the softening point or melting|fusing point of the resin which comprises, there exists a tendency which shrinkage|contraction and generation|occurrence|production of wrinkles etc. can be suppressed.

When the resin contained in the foam is a polyolefin-based resin, the temperature at the time of the heat-melting treatment is specifically preferably 100 to 300°C, more preferably 150 to 250°C, still more preferably 170 to 230°C. am.

Moreover, as a processing time of a heat melting process, although it changes with processing temperature, for example, 0.1 second - about 10 second is preferable, Preferably it is about 0.5 second - about 7 second. When the processing time is within the above range, sufficient time for melting can be ensured, and there exists a tendency that generation|occurrence|production of wrinkles etc. by excessive heating can be suppressed. And sufficient heat-melting process can be performed and the thickness precision of a foam improves.

It is preferable to use the thermal melting processing apparatus which can adjust the gap (gap, space|interval) through which a foam structure passes for the said thermal melting processing. As such a thermal melting processing apparatus, the continuous processing apparatus which has a heating roll (thermoelectric roll) which can adjust a gap is mentioned, for example.

In the lubricant reduction step, in order to reduce the lubricant content in the surface region to 70% by weight or less of the lubricant content in the inner region, the lubricant on one surface of the foam is decomposed or one of the foams is Move the lubricant away from the surface.

As a means for decomposing the lubricant, for example, a method of breaking the chemical bond constituting the lubricant with a highly reactive substance (eg, active oxygen), irradiating a high-energy electron beam to cut the chemical bond constituting the lubricant how to do it

As a method of generating active oxygen, a well-known thru|or a common method is mentioned. For example, the method of performing ultraviolet irradiation in the presence of oxygen, the method of performing corona discharge in the presence of oxygen, etc. are mentioned. Among them, the method of performing ultraviolet irradiation in the presence of oxygen is preferable because active oxygen can be efficiently obtained. In the method of irradiating ultraviolet light in the presence of oxygen, specifically, when a UV lamp having a strong emission wavelength around 185 nm and around 254 nm is used, oxygen molecules receive energy of a wavelength of 185 nm and are decomposed to generate oxygen atoms, and the oxygen Ozone is produced when atoms combine with oxygen molecules. Then, ozone is decomposed by receiving energy having a wavelength of 254 nm to generate active oxygen. In particular, emission wavelengths around 185 nm and around 254 nm are preferable because it is difficult to cut the molecules constituting the foam.

In the method of irradiating electron beams, electron beams are irradiated with low energy to such an extent that the resin or crosslinking agent in the foam is not crosslinked (so-called post crosslinking) and the physical properties of the foam are not changed.

The said ultraviolet irradiation and electron beam irradiation may be performed by a batch system, and may be performed by a continuous system.

Examples of the means for moving the lubricant include a method of volatilizing in air by heat, a method of eluting the lubricant into a soluble solvent, and a method of transferring the lubricant to the pressure-sensitive adhesive by applying and peeling it.

In the method of volatilizing in the air by heat, heating is performed with a low amount of heat such that the resin or crosslinking agent in the foam is not crosslinked (so-called post crosslinking) and the physical properties of the foam are not changed.

As a method of making it elute in the said solvent, the method of removing a surface solvent, after spraying a solvent on the surface of a foam and leaving it still for a fixed period of time, etc. are mentioned, for example.

In the method of moving to the said adhesive by apply|coating and peeling the said adhesive, it is a well-known thru|or a common adhesive tape which has an adhesive, and what can peel can be used. Specifically, the lubricant can be transferred to the pressure-sensitive adhesive by attaching an adhesive tape to the one surface of the foam, holding it for a certain period of time, and then peeling it off. It will not specifically limit as said adhesive as long as it has adhesiveness with respect to a foam and can be re-peelable, For example, well-known or customary adhesives, such as an acrylic type, a rubber type, silicone type, can be used. In addition, other characteristics, such as thickness, are not specifically limited, either. Since adhesive tape peeling is easy to perform a continuous mass process compared with a batch system, it is preferable. In addition, since the acrylic pressure-sensitive adhesive has high compatibility with the fatty acid amide lubricant, it is excellent in adsorption or absorption of the fatty acid amide lubricant present in the surface region of the foam, and is preferred.

The method of volatilizing in the air by the heat, the method of dissolving the lubricant into a soluble solvent, and the method of transferring the pressure-sensitive adhesive by applying and peeling the pressure-sensitive adhesive to the pressure-sensitive adhesive may be performed in a batch system or in a continuous system.

In this way, in the foam molding step, a resin composition containing a resin and a lubricant is foam-molded to obtain a foam, and if necessary, a slicing process or a heat melting treatment is performed, and then the lubricant in the surface region in the lubricant reduction step. By reducing content so that it may become 70 weight% or less of the lubricant content in the said internal area|region, the foam of this invention is obtained.

[No foaming]

The foam member of this invention contains the foam of this invention at least. The foam member of this invention may be comprised only with the foam of this invention, and may have other members other than the foam of this invention. As said other member, an adhesive layer, a base material layer, an adhesive sheet (for example, carrier tape), etc. are mentioned.

The foam of the present invention has good pick-up properties, and when it is peeled from the carrier tape, foam breakage hardly occurs. For this reason, in the foam member of this invention, it is preferable that the foam of this invention is used so that the said one surface may adhere to a carrier tape. Therefore, as a foam member of this invention which has members other than the foam of this invention, the foam member which has a carrier tape on the said one surface of the foam of this invention is mentioned, for example.

An adhesive sheet containing an adhesive layer may be sufficient as adhesive sheets, such as the said carrier tape, and the adhesive sheet which has an adhesive layer on at least single side|surface of a base material and this base material may be sufficient as it. Moreover, a single-sided adhesive sheet may be sufficient and a double-sided adhesive sheet may be sufficient. As said carrier tape, the carrier tape which has an adhesive layer on the single side|surface of a base material and this base material is preferable. Therefore, as the foam member of the present invention having a carrier tape, a carrier tape having a pressure-sensitive adhesive layer on at least one side of a substrate is provided, and the foam of the present invention and the carrier tape are formed between the one surface of the foam of the present invention and the carrier tape. The foam member laminated|stacked so that an adhesive layer may contact is preferable.

Moreover, the foam member of this invention WHEREIN: The foam of this invention may have an adhesive layer on one side or both surfaces. In particular, it is preferable to have a pressure-sensitive adhesive layer on the other surface. Moreover, when the foam member of this invention has a carrier tape on the said one surface of the foam of this invention, it is especially preferable to have an adhesive layer on the said other surface of the foam of this invention. If the foam member of this invention has an adhesive layer, for example, on the foam member of this invention, through an adhesive layer, the base for a process can be provided, and furthermore, it can be fixed or temporarily fixed to an adherend (eg, a housing or a component).

As an adhesive which forms the said adhesive layer (the adhesive layer in a carrier tape, and the adhesive layer which you may have on one side or both surfaces of a foam), For example, an acrylic adhesive, a rubber-type adhesive (natural rubber-type adhesive, synthetic rubber-type adhesive, etc.), silicone type A pressure-sensitive adhesive, a polyester pressure-sensitive adhesive, a urethane pressure-sensitive adhesive, a polyamide pressure-sensitive adhesive, an epoxy pressure-sensitive adhesive, a vinyl alkyl ether pressure-sensitive adhesive, a fluorine-based pressure-sensitive adhesive, and the like. An adhesive may use only 1 type and may use 2 or more types. In addition, the adhesive of any form, such as an emulsion-type adhesive, a solvent-type adhesive, a hot-melt type adhesive, an oligomer-type adhesive, and a solid adhesive, may be sufficient as an adhesive. As said adhesive, an acrylic adhesive is especially preferable from a viewpoint, such as contamination prevention with respect to a to-be-adhered body.

Although the thickness of the said adhesive layer is not specifically limited, 2-100 micrometers is preferable, More preferably, it is 10-100 micrometers. The thinner the pressure-sensitive adhesive layer, the higher the effect of preventing the adhesion of dust and dirt at the edges, so that the thickness is preferably thin. In addition, the adhesive layer may have any form of a single|mono layer and lamination|stacking.

The said adhesive layer may be provided on the foam of this invention through another layer (lower layer). As such a lower layer, another adhesive layer, an intermediate|middle layer, an undercoat layer, a base material layer (especially a film layer, a nonwoven fabric layer, etc.) etc. are mentioned, for example. In addition, the said adhesive layer may be protected by peeling films (separators), such as a release paper and a release film.

In FIG. 2, the schematic of an example of the foam member of this invention is shown. 2, the foam member 2 of this invention contains the foam 1 of this invention. On one surface 11 of the foam 1 of the present invention, a carrier tape 3 having a pressure-sensitive adhesive layer 3b on one side of the base material 3a is provided on one surface 11 and the pressure-sensitive adhesive surface of the pressure-sensitive adhesive layer 3b. They are stacked so that they contact each other. Moreover, the adhesive layer 4 is laminated|stacked on the other surface 12 of the foam 1 of this invention.

It is preferable that the foam member of this invention is used as objects for electrical and electronic equipment. In particular, it is preferable to use it as a sealing material or a vibration-proof material of an electric and electronic device. Moreover, it is preferably used as a shock absorber and shock absorber, especially as a shock absorber and shock absorber for electric and electronic devices. In addition, an "electrical/electronic device" means an apparatus corresponding to at least any one of an electric device and an electronic device. Moreover, by using the foam member of this invention for the said electrical/electronic device, it can be set as the electrical/electronic device of this invention. The electrical/electronic device of the present invention includes at least the foam member of the present invention.

As said electrical/electronic device, a portable electrical/electronic device is especially mentioned. Examples of such portable electrical and electronic devices include portable devices such as mobile phones, PHSs, smartphones, tablets (tablet-type computers), mobile computers (mobile PCs), personal digital assistants (PDAs), electronic notebooks, portable televisions, and portable radios. A broadcast receiver, a portable game machine, a portable audio player, a portable DVD player, cameras, such as a digital camera, a camcorder type video camera, etc. are mentioned. Moreover, as electrical/electronic devices other than the said portable electrical/electronic device, a household electrical appliance, a personal computer, etc. are mentioned, for example.

In particular, as various members (parts) that the foam member of the present invention can be installed (mounted) to the electrical and electronic equipment, for example, it is mounted on an image display device such as a liquid crystal display (LCD), an electroluminescent display, and a plasma display. Optical members or optical parts such as an image display member (display unit) (especially a small image display member), a camera or lens (especially a small camera or lens) mounted on a mobile communication device such as a mobile phone or a portable information terminal can be heard

As a preferable use form of the foam member of the present invention, for the purpose of, for example, dust proofing, light blocking, buffering, etc., a form of sandwiching around a display unit such as an LCD or between a display unit such as an LCD and a housing (window unit) is mentioned. .

[Example]

The present invention will be described in more detail below with reference to Examples, but the present invention is not limited by these Examples at all.

(Production Example 1 of foam)

Block copolymer of polybutylene terephthalate as a hard segment and polyether as a soft segment (trade name "Pelprene P-90BD02", manufactured by Toyobo Co., Ltd., melt flow rate at 230°C: 2.4 g/10 min): 100 parts by weight , acrylic lubricant (trade name "Metablen L-1000", manufactured by Mitsubishi Rayon Co., Ltd., containing nitrogen atom-containing compound): 5 parts by weight, hard clay (trade name "ST-301", manufactured by Shiraishi Calcium Co., Ltd., Surface-treated with a silane coupling agent): 1 part by weight, carbon black (trade name "Asahi #35", manufactured by Asahi Carbon Co., Ltd.): 5 parts by weight and an epoxy modifier (epoxy-modified acrylic polymer, weight average molecular weight ( Mw): 50000, epoxy equivalent: 1200 g/eq, viscosity: 2850 mPa·s): 1.5 parts by weight, kneaded by a twin-screw kneader at a temperature of 220° C., extruded into a strand shape, and cut into pellets after cooling with water was molded. And the pellet-type polyester-type resin composition was obtained.

This pellet-type polyester resin composition was put into a tandem single screw extruder (manufactured by Nippon Sekosho Co., Ltd.), and carbon dioxide gas was injected at a pressure of 17 (13 after injection) MPa in an atmosphere of 240°C. After the carbon dioxide gas was sufficiently saturated, it was cooled to a temperature suitable for foaming, and extruded from a die to obtain a sheet-like polyester resin foam having a thickness of 2.0 mm.

The obtained foam was sliced and the foam whose thickness is 1.1 mm was obtained. The foam was subjected to a roll gap adjustment thermal laminator (device name "MRK-6504", manufactured by MCK Co., Ltd.) under the conditions of gap: 0.95 mm, roll temperature: 190 ° C., processing speed: 12 m/min. Foam A was obtained by performing a heat-melting process.

(Production Example 2 of the foam)

Polypropylene [melt flow rate (MFR): 0.35 g/10 min]: 35 parts by weight, thermoplastic elastomer composition [polypropylene (PP) and ethylene/propylene/5-ethylidene-2-norbornene three-dimensional copolymer (EPT) Blend (crosslinked olefinic thermoplastic elastomer, TPV), the ratio of PP and EPT is 25/75 by weight, including 15.0 wt% of carbon black]: 60 parts by weight, lubricant (1 part by weight of monoglyceride stearate) Masterbatch containing 10 parts by weight of polyethylene): 5 parts by weight, nucleating agent (magnesium hydroxide, average particle diameter: 0.8 μm): 10 parts by weight, lubricant (erucanamide, melting point 80 to 85° C.): 2 parts by weight After kneading at a temperature of 200° C. with a twin-screw kneader, it was extruded into a strand shape, cooled with water, and then cut and molded into a pellet shape.

This pellet was put into a single screw extruder, and carbon dioxide gas was injected at a pressure of ^{17 (13 after injection) MPa/cm 2 in an atmosphere of 240°C.} After the carbon dioxide gas was sufficiently saturated, it was cooled to a temperature suitable for foaming, and then extruded from a die to obtain a polypropylene resin foam.

Foam B was obtained by subjecting the obtained foam to a surface thermal melting treatment using a dielectric heating roll (manufactured by Tokuden Co., Ltd.) under the conditions of roll temperature: 170°C and processing speed: 12 m/min.

(Example 1)

Foam A obtained in Foam Production Example 1 was subjected to surface heat fusion treatment in the presence of air from the side, using a low pressure mercury lamp (trade name "QGL400U-3", manufactured by Iwasaki Denki Co., Ltd.), illuminance 90 mW UV irradiation was performed under the conditions of /cm ² and light quantity of 1000 mJ/cm ^{2 .}

(Example 2)

After bonding an acrylic adhesive tape (trade name "ECT755", manufactured by Nitto Denko Co., Ltd.) to the surface to which the surface heat-melting treatment of the foam A obtained in Production Example 1 of foam was given, and aging at room temperature for 24 hours, adhesion The tape was removed.

(Example 3)

Foam B obtained in Foam Production Example 2 was subjected to surface heat fusion treatment in the presence of air from the side, using a low pressure mercury lamp (trade name "QGL400U-3", manufactured by Iwasaki Denki Co., Ltd.), illuminance 90 mW UV irradiation was performed under the conditions of /cm ² and light quantity of 1000 mJ/cm ^{2 .}

(Example 4)

An acrylic adhesive tape (trade name "SPV-C-600", manufactured by Nitto Denko Co., Ltd.) was bonded to the surface of the foam B obtained in Production Example 2 of the foam subjected to surface heat melting treatment, and aging was performed at room temperature for 24 hours. After carrying out, the adhesive tape was peeled off.

(Comparative Example 1)

Foam A obtained in Production Example 1 of the foam was used as it was.

(Comparative Example 2)

Foam B obtained in Preparation Example 2 of the foam was used as it was.

<Evaluation>

The following evaluation was performed about the foam (foam sheet|seat) obtained by the Example and the comparative example. A result is shown in Table 1.

(Ratio of nitrogen atom-containing compounds)

As the content ratio of the lubricant, the ratio of the nitrogen atom-containing compound was measured.

A TOF-SIMS (ION-TOF Co., Ltd., trade name: "TOF-SIMS5") Primary ion acceleration voltage 25kV as a Bi ₃ ^{+ 2,} by the irradiation to the surface of the foam having a thickness of 400㎛, government (正負) 2 Secondary Ion A mass spectrum was obtained. The ratio of the mass spectral intensity of nitrogen atom containing and the mass spectral intensity of a standard sample (C ₇ H ₅ O ^{− ) was taken as the relative intensity.} The relative intensity of the nitrogen atom-containing compound in the depth direction was measured, and the relative intensity of the nitrogen atom-containing compound present in the surface region (region of 50 nm from the surface to the inside) and the inner region (the foam surface so that the foam was halved in thickness) Measure the relative intensities of the nitrogen atom-containing compounds present in the 50 nm region from the cut plane parallel to the inner region), calculate the ratio of these relative intensities, and calculate the ratio of the nitrogen atom-containing compounds in the surface region to the internal region. It was set as the abundance ratio.

And, in the foams obtained in Examples and Comparative Examples, since a nitrogen atom-containing compound was used as the lubricant, the ratio of the lubricant content in the surface area to the inner area as the relative ratio of the nitrogen atom-containing compound in the surface area to the inner area was done with

(average cell diameter)

An enlarged image of the bubble portion of the foam was introduced with a digital microscope (trade name "VHX-500", manufactured by Keyence Co., Ltd.), and image analysis was performed using the analysis software of the same measuring instrument to obtain the cell diameter (μm) of each cell. ), and the average cell diameter (μm) was obtained. The number of bubbles in the introduced enlarged image is about 200. Note that the cell diameter is obtained by calculating the area of the cell and converted to the equivalent circle diameter.

(Apparent density)

The density (apparent density) of the foam was calculated as follows. The foam of each Example and Comparative Example was punched out to a size of 20 mm x 20 mm to be a test piece, the dimension of the test piece was measured with a vernier caliper, and the volume of the test piece was calculated. Then, the mass of the test piece was measured with an electronic balance. And it computed by the following formula.

Apparent density (g/cm ³ ) = mass of test piece/volume of test piece

(Repulsive force at 50% compression (Great repulsion load at 50% compression, 50% compression load))

It measured according to the compression hardness measurement method described in JISK6767.

The foam was cut out to width: 30 mm x length: 30 mm, and it was set as the sheet-shaped test piece. Next, the stress (N) when the test piece is compressed in the thickness direction at a compression rate of 10 mm/min until the compressibility becomes 50% is ^{converted per unit area (1 cm 2} ), and the repulsive force (N/cm ^{2 )} ) was set.

(to carrier tape peel force)

After storing the foam (width: 20mm×length: 120mm) for more than 24 hours under an atmosphere of temperature: 23±2°C, humidity: 50±5RH% (pretreatment conditions are in accordance with JIS Z 0237), width: 30mm×length : 120 mm non-adhesive carrier tape (trade name "3164S", manufactured by Kern, single-sided adhesive tape with base material, base material: PET base material, vs. SUS adhesive force (tensile speed: 0.3 m/min): 0.15 N/20 mm), or weakly adhesive carrier On the surface of the adhesive layer of the tape (trade name "3165S", manufactured by Kern, single-sided adhesive tape with a base material, base material: PET base material, vs. SUS adhesive force (tensile speed: 0.3 m/min): 0.35 N/20 mm), the surface heat-melting treatment was applied In a form in which the applied surface and the pressure-sensitive adhesive layer surface of the carrier tape contact each other, pressure-bonding was performed on a 2 kg roller and one reciprocating condition, and it was left to stand for 24 hours to obtain a measurement sample.

A strong adhesive double-sided adhesive tape (brand name "No. 500", manufactured by Nitto Denko Co., Ltd.) so that the surface of the sample for measurement on the carrier tape substrate side does not float or peel off from the support plate (bakelite plate with a thickness of 2 mm) during measurement. ) interposed on the support plate, and the force required for peeling the foam from the carrier tape under the atmosphere of temperature: 23±2° C. and humidity: 50±5 RH% under peeling conditions (tensile speed: 0.3 m/ min) to determine the adhesive force (N/20 mm).

The peeling force of the carrier tape in the case of using the non-adhesive carrier tape was defined as the "to-non-adhesive carrier tape peeling force", and the peeling force of the carrier tape in the case of using the weak-adhesive carrier tape was defined as the "to the weak-adhesive carrier tape peeling force". Table 1 shows.

(pick-up)

After storing the foam (width: 10mm × length: 120mm) for more than 24 hours under an atmosphere of temperature: 23±2℃ and humidity: 50±5RH% (pretreatment conditions are in accordance with JIS Z 0237), width: 10mm×length: It was fixed to the silicone-treated release paper using a 120 mm double-sided adhesive tape (trade name "No. In a form in which the surface of the adhesive layer of the tape (trade name "3164S", manufactured by Kern) was in contact, it was pressed under the conditions of a 2 kg roller and one reciprocation, and left to stand for 24 hours to obtain a measurement sample.

When the carrier tape of the sample for measurement could be lifted by hand, the pick-up property was described as "○", and when the carrier tape peeled and could not be lifted, the pick-up property was evaluated as "x".

(Destroy the form)

After storing the foam (width: 10mm × length: 120mm) for more than 24 hours under an atmosphere of temperature: 23±2℃ and humidity: 50±5RH% (pretreatment conditions are in accordance with JIS Z 0237), width: 10mm×length: It was fixed to the SUS plate using 120 mm double-sided adhesive tape (trade name "No.5603", manufactured by Nitto Denko Co., Ltd.), and the opposite side of the foam and the adhesive layer of the weakly adhesive carrier tape (trade name "3165S", manufactured by Kern) In the form in which the surface was in contact, it was pressed under the conditions of a 2 kg roller and one reciprocation, and left to stand for 24 hours to obtain a measurement sample.

The carrier tape was quickly removed by hand, and the peeling state was visually confirmed to evaluate whether or not surface breakage of the foam occurred.

In Table 1, when there was no surface breakage of the foam, it was described as "○", and when the surface breakage of the foam occurred, it was described as "x".

As shown in Table 1, the foams of Examples were obtained with good moldability, and had good pick-up properties for non-adhesive carrier tapes, and also had a high peeling force to not only non-adhesive carrier tapes but also weakly adhesive carrier tapes, resulting in high adhesiveness. This was good. In addition, even when a weakly adhesive carrier tape was used, foam breakage did not occur at the time of peeling. For this reason, in the foam of an Example, since both a non-adhesive carrier tape and a weakly adhesive carrier tape can be used, the selection range of a carrier tape is wide. On the other hand, in the foams of Comparative Examples 1 and 2, the content of the nitrogen atom-containing compound in the surface region relative to the inner region, that is, the content of the lubricant, was 100% by weight, and the peeling force to the non-adhesive carrier tape and the weakly adhesive carrier tape was relatively low. It was small and had poor adhesion. In addition, the pickup property was also poor.

1: Foam of the present invention
11: one surface
12: the other surface
13: surface area
14: inner area
2: Foam member of the present invention
3: carrier tape
3a: description
3b: adhesive layer
4: adhesive layer
L: Cutting surface when the foam (1) of the present invention is cut parallel to the surface of the foam so that the thickness is half

Claims (9)

It is a single sheet-like foam, and the content of the lubricant in a region from one surface of the foam to a depth of 50 nm in the thickness direction is the thickness from the cut surface when the foam is cut parallel to the foam surface so that the thickness becomes half The foam member which has a foam whose content is 70 weight% or less of the lubricant in the area|region up to the depth of 50 nm in a direction. According to claim 1,
The foam member has an apparent density of 0.01 to 0.20 g/cm ³ , a repulsive force at 50% compression of 0.1 to 4.0 N/cm ² , and an average cell diameter of 10 to 200 μm. 3. The method of claim 1 or 2,
The one surface of the foam and the adhesive surface of the pressure-sensitive adhesive sheet having an adhesive force to the SUS plate (temperature: 23±2°C, humidity: 50±5RH%, tensile rate: 0.3m/min) of 0.15N/20mm were bonded The foam member, wherein the peeling force (temperature: 23±2°C, humidity: 50±5RH%, tensile rate: 0.3 m/min) when the foam is peeled from the pressure-sensitive adhesive sheet is 0.10 to 2.00 N/20 mm. 3. The method of claim 1 or 2,
The one surface of the foam and the adhesive surface of the pressure-sensitive adhesive sheet having an adhesive force to the SUS plate (temperature: 23±2°C, humidity: 50±5RH%, tensile rate: 0.3m/min) of 0.35N/20mm were bonded, The foam member, wherein the peeling force (temperature: 23±2°C, humidity: 50±5RH%, tensile rate: 0.3 m/min) when the foam is peeled from the pressure-sensitive adhesive sheet is 0.10 to 2.00 N/20 mm. 3. The method of claim 1 or 2,
The foam member which has an adhesive layer on the other surface of the said foam. 3. The method of claim 1 or 2,
A foam member having a carrier tape having a pressure-sensitive adhesive layer on at least one side of a substrate, wherein the foam and the carrier tape are laminated so as to contact the one surface of the foam and the pressure-sensitive adhesive layer of the carrier tape. 3. The method of claim 1 or 2,
A foam member used as an object for electrical and electronic equipment. An electric/electronic device comprising the foam member according to claim 1 or 2. A step of foam molding a resin composition containing a resin and a lubricant to obtain a sheet-like foam, and decomposing or moving the lubricant from one surface of the foam, and the content of the lubricant in the region from the one surface to a depth of 50 nm in the thickness direction a step of reducing the content of the lubricant in the region from the cutting surface to a depth of 50 nm in the thickness direction when the foam is cut parallel to the surface of the foam to half the thickness to 70% by weight or less; , a method of manufacturing the foam.

Images