CN103569491A

CN103569491A - Cover piece for preventing contents adhering

Info

Publication number: CN103569491A
Application number: CN201310332056.2A
Authority: CN
Inventors: 羽野隆之; 唐津诚
Original assignee: Showa Denko Packaging Co Ltd
Current assignee: Lishennoco Packaging Co.,Ltd.
Priority date: 2012-08-01
Filing date: 2013-08-01
Publication date: 2014-02-12
Anticipated expiration: 2033-08-01
Also published as: KR102077864B1; CN103569491B; KR20140017437A

Abstract

The invention provides a cover piece for preventing contents adhering. The outer surface of a thermal heating layer (5) stacked on a substrate layer (1) adopts wet silicon dioxide particles to form an anti-adhering layer (6). The wet silicon dioxide particles are formed by conducting hydrophobic treating on polyorganosiloxane having over 100cst of viscosity and especially dimethyl polysiloxane, which are used as treating agents. Or the outer surface of the thermal heating layer (5) stacked on the substrate layer (1) adopts the following wet silicon dioxide particles to form an anti-adhering layer (6). The wet silicon dioxide particles are hydrophobic wet silicon dioxide particles, whose di-n-butylamide adhering amount (DBA adhering amount) is below 200mmol/kg. The cover piece for preventing contents adhering is advantageous in that thermal sealing performance and sealing performance are well maintained; content like yoghourt can be effectively prevented from being adhered to the back face of the cover.

Description

Prevent the cover piece that content adheres to

Technical field

The present invention relates to be mainly used in the heat-sealing cover piece of the container for packing of foodstuff, more particularly, the cover piece with anti-content tack that relates to the wrapping cup-like containers that is applied to Yoghourt, fruit jelly, pudding, jam, coffee with milk (Caffellatte) etc.

Background technology

The cover piece (lid material) of (heat-seal) use is sealed in the heat-sealing of this kind, generally form the aluminium foil surface side of the substrate layer forming at the lamination by base material film and aluminium foil, across middle resin layer, be provided with as required heat sealing agent, instant heating and seal the cover piece of layer (heat-seal layer), it covers opening on the container body of cup-shaped of packed article of having filled Yoghourt etc., by by circumference heat fusion on the upper limb flange part of container body, form hermetically sealed package.

Therefore, such cover piece, be required good heat sealability, leak tightness and for the suitable easy fissility breaking a seal in, wish to there is the non-tack of content, can prevent that content is attached to the cover piece back side (the inside) of the inner face side of container.If content is attached to the back side of cover piece, in when Kaifeng, have the anxiety of the finger of making dirty, clothes or periphery, and produce the waste that damage is brought of abandoning by content, or cost strips the man-hour of attachment, and produce and cause the unfavorable of unclean sense etc.

For such requirement, in the past about possessing the cover piece of anti-content adhesion value, the motion as shown in following

patent documentation

1,2 had once been proposed.

Formerly technology shown in patent documentation 1, is in heat-sealing, to seal the outside face of layer, as anti-content adhesion layer, forms the porous layer of the tridimensional network that the hydrophobic oxide fine particle by fine hydrophobic silica etc. forms.

The formerly motion technology of this patent documentation 1, although preventing obtaining excellent effect aspect content adhesion effect, but the heat stability (resistance to effect of heat) of anti-adhesion layer is poor, in the situation that stand bad hot resume, has the easy damaged difficult point of the adhesion effect of preventing., as hydrophobic oxide fine particle, it is the so ultramicrofine hydrophobic oxide fine particle of 3～100nm that the primary particle mean grain size that the silicon dioxide microparticle manufactured by dry process is typical example is take in use, the heat-sealing that it is particularly applied to have general hot melt type is sealed in the situation of formation of anti-content adhesion layer of cover piece of layer, during dry after the particle dispersion liquid coating in the formation operation of anti-adhesion layer, if heating-up temperature is high, or drying time is elongated, prevent that content adhesion effect is significantly impaired, likely can not maintain stable anti-adhesion performance.The difficult point that process management while therefore, having cover piece manufacture becomes and a little bothers.

Stable on heating problem like this; can think due to following reason: the radiant heat that carrys out self-heating platform in the heat when dry or the standby when heat-sealing is sealed; hotmelt (the hot-melt adhesive: heat melt adhesive) during melting of layer is sealed in heat-sealing; fine oxide fine particle sinks in hotmelt; or; the molten component of hotmelt enters into the gap between particulate by capillarity, between landfill particle, lowers the hydrophobic (drying of hydrophobic silica; Refuse water) property face area, can not fully be prevented content adhesion effect thus.

On the other hand, problem for the particularly heat stability of the formerly technology of patent documentation 1 as described above, as the improvement technology of seeking to address this problem and can guarantee excellent non-tack, the inventor had previously proposed the invention of recording in patent documentation 2.

This improves motion technology, and its principal character is: as the formation material of anti-adhesion layer, replace the use of known hydrophobic dry type silicon dioxide in the past, use hydrophobic wet silicon dioxide particle.General its particle diameter of wet silicon dioxide particle is micron-scale, more much larger than dry type silicon dioxide granule.Therefore, in heat-sealing, seal layer consist of hotmelt in the situation that, even this adhesives melting, hydrophobic silica particle is also difficult to sink to heat-sealing and seals in layer.Therefore, easily maintain well the surperficial hydrophobic nature of anti-adhesion layer.Thus, than the formerly technology of patent documentation 1, can improve hot impact.

But, on the other hand, because its particle diameter ratio of wet silicon dioxide particle is larger, the situation of the dry type silicon dioxide granule therefore forming with the agglomerate using by ultramicrofine primary particle is compared, poor with the surface hydrophobicity in the relativeness of coating weight (adhesion amount), in order to obtain the coating of the hydrophobic wet silicon dioxide of the amount that high anti-adhesion performance need is slightly many, therefore, also have that with respect to heat-sealing, to seal the adherence of layer (closely sealed; Adhesion) difficult point of the easy variation of property, for practical, the further improvement of these aspects of strong request.

Patent documentation 1: No. 4348401 communique of Japanese Patent

Patent documentation 2: No. 4668352 communique of Japanese Patent

Summary of the invention

The present invention is the invention completing corresponding to requirement as described above of the prior art, specifically, its objective is following improvement technology is provided: even if there is the heat affecting of being subject to, also can maintain the good resistance to effect of heat of sufficient anti-content adhesion value, even and the coating weight of few wet silicon dioxide particulate also can be guaranteed high anti-content adhesion value, and can guarantee well that hydrophobic wet silicon dioxide particulate seals the adherence of layer with respect to heat-sealing, can guarantee the above-mentioned stable continuation that prevents content adhesion effect.

The result that the inventor repeatedly diligently tests and studies under above-mentioned object, find: according to the formerly technology of above-mentioned patent documentation 2, make the layer of anti-adhesion layer for being formed by hydrophobic wet silicon dioxide, and, by using, this hydrophobic wet silicon dioxide has been carried out to the hydrophobic wet silicon dioxide particle that hydrophobization is processed with specific inorganic agent especially, use particular viscosity region polysiloxane hydrophobization wet silicon dioxide particle (the 1st invention), or, by the hydrophobic wet silicon dioxide particle with the hydrophobic rate of height more than specified value (the 2nd invention) that uses hydrophobization especially to heavens to process, can very effectively solve above-mentioned problem, to such an extent as to completed the present invention.

That is, the present invention, as its feature item, proposes following scheme.

［ 1 ］ a kind of cover piece that prevents that content from adhering to, at least to there is substrate layer and layer is sealed in heat-sealing, and at the outside face that layer is sealed in this heat-sealing, be provided with the heat-sealing cover piece of anti-adhesion layer, it is characterized in that, the hydrophobic wet silicon dioxide particle that above-mentioned anti-adhesion layer has carried out hydrophobization processing by polysiloxane more than use viscosity 100cst forms.

［ 2 ］ a kind of cover piece that prevents that content from adhering to, at least to there is substrate layer and layer is sealed in heat-sealing, and at the outside face that layer is sealed in this heat-sealing, be provided with the heat-sealing cover piece of anti-adhesion layer, it is characterized in that, above-mentioned anti-adhesion layer is that hydrophobic wet silicon dioxide particle below 200mmol/kg forms by di-n-butyl amine adsorbance.

［ 3 ］ according to the cover piece that content adheres to that prevents described in preceding paragraph 1, the di-n-butyl amine adsorbance of above-mentioned hydrophobic wet silicon dioxide particle is below 200mmol/kg.

［ 4 ］, according to the cover piece that content adheres to that prevents described in preceding

paragraph

1 or 3, for the viscosity of the above-mentioned polysiloxane of hydrophobization inorganic agent, be below 2000cst.

［ 5 ］, according to the cover piece that content adheres to that prevents described in preceding

paragraph

1,3 or 4, for the above-mentioned polysiloxane of hydrophobization inorganic agent, be dimethyl polysiloxane.

［ 6 ］ according to the cover piece that content adheres to that prevents described in preceding

paragraph

2 or 3, the di-n-butyl amine adsorbance of above-mentioned hydrophobic wet silicon dioxide particle is 30～100mmol/kg.

［ 7 ］, according to the cover piece that content adheres to that prevents described in any one of preceding paragraph 1～6, the coating weight of the hydrophobic wet silicon dioxide particle in above-mentioned anti-adhesion layer, counts 0.1～1.0g/m to be dried rear weight ².

［ 8 ］, according to the cover piece that content adheres to that prevents described in any one of preceding paragraph 1～7, the mean grain size of above-mentioned hydrophobic wet silicon dioxide particle is 0.5～7.0 μ m.

［ 9 ］ according to the cover piece that content adheres to that prevents described in any one of preceding paragraph 1～8, above-mentioned heat-sealing is sealed layer and is formed as resin combination that must composition by containing ethene-beta-unsaturated esters copolymer, wax and tackifier, the softening point of above-mentioned resin combination is more than 90 ℃, and the fusing point of above-mentioned wax is more than 80 ℃.

［ 10 ］ according to the cover piece that content adheres to that prevents described in preceding paragraph 9, the softening point of above-mentioned resin combination is more than 100 ℃, and the fusing point of above-mentioned wax is more than 90 ℃.

［ 11 ］ according to the cover piece that content adheres to that prevents described in preceding paragraph 9 or 10, the fusing point of above-mentioned ethene-beta-unsaturated esters copolymer is 70～100 ℃.

［ 12 ］ according to the cover piece that content adheres to that prevents described in any one of preceding paragraph 1～8,

Above-mentioned heat-sealing is sealed layer and is formed as resin combination that must composition by containing ethene-beta-unsaturated esters copolymer, wax and tackifier,

The fusing point of above-mentioned ethene-beta-unsaturated esters copolymer is 70～100 ℃,

The fusing point of above-mentioned wax is 80～130 ℃,

The softening point of above-mentioned resin combination is set to 90～160 ℃.

［ 13 ］ according to the cover piece that content adheres to that prevents described in any one of preceding paragraph 9～12, it is characterized in that, it is that 30～50 % by weight, wax are that 30～50 % by weight, tackifier are the composition of 5～25 % by weight that above-mentioned resin combination has above-mentioned ethene-beta-unsaturated esters copolymer.

［ 14 ］ according to the cover piece that content adheres to that prevents described in any one of preceding paragraph 1～13, the oil absorption of above-mentioned hydrophobic wet silicon dioxide particle is more than 50ml/100g.

［ 15 ］, according to the cover piece that content adheres to that prevents described in any one of preceding paragraph 1～14, it is that resin combination below 4000mPas forms that layer melt viscosity above by 90 ℃ of softening points, at 160 ℃ are sealed in above-mentioned heat-sealing.

［ 16 ］ according to the cover piece that content adheres to that prevents described in any one of preceding paragraph 1～8,

The softening point of above-mentioned wax and tackifier or fusing point are 80～130 ℃,

The softening point of above-mentioned resin combination is 90～160 ℃, and the melt viscosity at 160 ℃ is 2000～4000mPas.

［ 17 ］ according to the cover piece that content adheres to that prevents described in any one of preceding paragraph 1～8,

Above-mentioned heat-sealing is sealed layer and is resin, forms as resin combination that must composition with wax and/or tackifier by containing acid modified polyolefin,

The fusing point of above-mentioned wax and tackifier is all more than 80 ℃.

［ 18 ］ according to the cover piece that content adheres to that prevents described in any one of preceding paragraph 1～17,

In above-mentioned heat-sealing, seal the outside face of layer, spread all over whole the dense a plurality of microspikes that are provided with below height 100 μ m in ground,

There is the above-mentioned outside face of this projection, be formed with above-mentioned anti-adhesion layer,

Above-mentioned anti-adhesion layer, its adhesion amount is set to 0.05g/m ²above and cover a little at the most below the amount of top end face of above-mentioned microspike.

［ 19 ］, according to the cover piece that content adheres to that prevents described in any one of preceding paragraph 1～18, the surperficial coefficient of static friction of above-mentioned anti-adhesion layer side is set to below 0.65.

In ［ 1 ］ invention (the 1st invention), the formation of the anti-adhesion layer on layer is sealed in heat-sealing, has used the hydrophobic wet silicon dioxide particle that particle diameter ratio is larger.Therefore, in heat-sealing, seal layer formed by hotmelt in the situation that, even this adhesives melting, owing to comparing with using the situation of ultramicrofine dry type silicon dioxide, therefore particle diameter is large, and above-mentioned particle is also difficult to sink to heat-sealing and seals in layer, does not reduce significantly the area that exposes on its surface.And then, can effectively prevent the reduction by the anti-adhesion performance due to heat affecting.Although the formerly technology shown in this and above-mentioned patent documentation 2 is same, but in the present invention, and then as above-mentioned hydrophobic wet silicon dioxide particle, used especially and carried out with polysiloxane hydrophobization inorganic agent more than viscosity 100cts the hydrophobic silica particle that hydrophobization is processed.Such hydrophobic silica particle, presents high hydrophobic nature on himself surface, and the anti-adhesion layer therefore being formed by this hydrophobic wet silicon dioxide, under the coating weight of fewer silicon dioxide granule, gives full play to the anti-adhesion performance of excellence.And, owing to adopting few coating weight enough, therefore can keep well silicon dioxide granule with respect to heat-sealing, to seal stationarity, the adherence of layer, can avoid silicon dioxide granule due to adhesion force deficiency come off, peel off caused through time performance reduce, unhygienic.

The mechanism that can access such effect is not necessarily clear and definite, but can infer as follows.Originally, hydrophobic silica, by surface being had to the wetting ability silicon dioxide granule of hydrophilic silanol base, adopted hydrophobization to process, and the hydrophobic group that is representative in order to methyl replaces surface hydrophilic base, manufactures.The organo-silicon compound that use as hydrophobization inorganic agent, there are halosilanes, hexamethyldisilazane, organopolysiloxane (polysiloxane) etc., wherein, use facture simple, excellent and the most common with respect to wet silicon dioxide hydrophobization effect, from the easy polysiloxane of market purchase, be favourable.In this situation, if the viscosity of polysiloxane is low, mol wt is also low, and the strand of the hydrophobic group therefore importing has the tendency shortening.On the other hand, the particle of wet silicon dioxide, as the structure of himself, is that the agglomerate by a plurality of minimum minuteness particles forms, and therefore, this wet silicon dioxide particle self, its inside have extremely most minute aperture of including air in.Therefore, carried out the hydrophobic silica particle that hydrophobization is processed, by the hydrophobic group replacing on surface and the synergy of bringing inner air into, and demonstration hydrophobic nature, even if but adopt above-mentioned hydrophobization to process, also the whole of hydrophilic group that can be not surperficial are replaced by hydrophobic group, remaining hydrophilic silanol base in a surperficial part.Much less, this remaining silanol base is towards the directive effect that reduces the hydrophobic nature of particle surface.Under such prerequisite, by using, by viscosity, be the hydrophobization inorganic agent that polysiloxane more than 100cst forms, the strand of hydrophobic group becomes longer, can effectively be covered by this strand the surface of remaining silanol base.Therefore, can make the hydrophobization degree of hydrophobization wet silicon dioxide particle is higher hydrophobization degree, can under a small amount of coating weight, present the anti-adhesion performance of actv..The viscosity of polysiloxane is during lower than 100cst, and the strand of hydrophobic group shortens, and therefore can not expect above-mentioned effect.

In ［ 2 ］ invention (the 2nd invention), the formation of the anti-adhesion layer on layer is sealed in heat-sealing, uses the larger hydrophobic wet silicon dioxide particle of particle diameter ratio.Therefore, in heat-sealing, seal layer formed by hotmelt in the situation that, even this adhesives melting, compare with the situation of the ultramicrofine dry type silicon dioxide of use, therefore particle diameter is large, and above-mentioned particle is difficult to sink to heat-sealing and seals in layer, can not reduce significantly the area that exposes on its surface.And, can effectively prevent the reduction by the anti-adhesion performance due to heat affecting.Although the formerly technology shown in this and above-mentioned patent documentation 2 is same, but in the present invention, and then as above-mentioned hydrophobic wet silicon dioxide particle, use height hydrophobization especially wet silicon dioxide, use that by surface treatment, to be become the adsorbance of di-n-butyl amine be the hydrophobization wet silicon dioxide particle below 200mmol/kg specifically.Such hydrophobic silica particle, the surface of himself has high hydrophobic nature, and the anti-adhesion layer therefore being formed by this hydrophobic wet silicon dioxide is given full play to excellent anti-adhesion performance under the coating weight of fewer silicon dioxide granule.And, owing to adopting few coating weight enough, therefore can keep well silicon dioxide granule with respect to heat-sealing, to seal stationarity, the adherence of layer, can avoid silicon dioxide granule due to adhesion force deficiency come off, peel off caused through time performance reduce, unhygienic.

At this, the di-n-butyl amine adsorbance of hydrophobic silica (hereinafter referred to as " DBA adsorbance "), becomes the index of the degree that represents hydrophobization.That is, common silicon dioxide, even adopt any method for making of dry type method for making and wet type method for making to form, all has a large amount of silanol base as hydrophilic group in its surface.Di-n-butyl amine, with silanol radical reaction, is adsorbed on silicon dioxide granule to ionic bond.On the other hand, hydrophobic silica, can by by the wetting ability silicon dioxide granule originally on surface with silanol base by silanes and/or polysiloxane-basedly carry out hydrophobization processing, thereby the hydrophobic group that is representative in order to methyl replacement surface hydrophilic base is manufactured thus.But, even if hydrophobization is processed, be not that the whole of surface hydrophilic base are replaced by hydrophobic group yet, remaining unreacted silanol base to a certain degree inevitably.And particularly in the situation of wet silicon dioxide particle, the particle structure of himself is that the agglomerate by most minimum particulates forms, and has the porous structure of most minute apertures in inside, the therefore also remaining unreacted wetting ability silanol base in inside.Therefore, by making to have carried out the silicon dioxide granule absorption di-n-butyl amine that hydrophobization is processed, measure its adsorbance, can know the hydrophobic degree of silicon dioxide granule.

In addition, hydrophobic wet silicon dioxide particle, has with the remaining silanol base to a certain degree of unreacted state on surface and inside as described above.Because this silanol base is wetting ability, therefore to heating and melting the affinity of resinous principle poor, and then hinder the infiltration of this resinous principle.That is, in the high heat affecting applying because of when heat-sealing, heat-sealing seal layer the melting of low-melting-point resin composition time, also act on and make to stop it to be penetrated into hastily gap between silicon dioxide granule and the micropore of inside particles because of capillarity.Therefore, prevent the significantly attenuating of the hydrophobic surface due to excessively being covered by resinous principle by particle surface and internal voids, alleviate the performance degradation due to heat affecting.That is to say, can contribute to improve the resistance to effect of heat of anti-adhesion layer.

In ［ 3 ］ invention, there is the formation of ［ 1 ］ invention and this two side of formation of ［ 2 ］ invention, therefore can guarantee above-mentioned ［ 1 ］ and ［ 2 ］ this two side's effect.

As ［ 4 ］ invention, for the viscosity of the above-mentioned polysiloxane of hydrophobization inorganic agent, be preferably below 2000cst.When thereby it is too high over 2000cst, instead cause the reduction tendency of surface hydrophobicity.Can think that this is due to following reason: the strand of hydrophobic group is elongated covers the surperficial micropore of silicon dioxide granule for more than needing, and air can not be brought in particle, and result, can not give full play to the hydrophobic effect being brought by air.

In ［ 5 ］ invention, the polysiloxane by as hydrophobization inorganic agent is used dimethyl polysiloxane, can use the most common, easily buy and cheap inorganic agent is simple and easy and effectively hydrophobization process desirable hydrophobization degree.

In ［ 6 ］ invention, use is controlled at DBA adsorbance on the hydrophobic wet silicon dioxide particle of the scope of 30～100mmol/kg, therefore utilize hydrophobic, the surface hydrophobicity of the height himself having, can realize more excellent anti-adhesion performance and good adherence.

In ［ 7 ］ invention, by the coating weight of hydrophobic silica particle (adhesion amount) is set as to 0.1～1.0g/m to be dried rear weighing scale ², can give necessity and sufficient anti-adhesion performance to anti-adhesion layer.

In ［ 8 ］ invention, by using mean grain size as hydrophobic wet silicon dioxide particle, it is the hydrophobic wet silicon dioxide particle of 0.5～7.0 μ m, can maintain the good adherence of heat-sealing being sealed to layer, and can not damage the heat sealability that layer is sealed in heat-sealing, aspect the sealing property of sealing intensity, container, can present homogeneous and stable excellent performance.

In ［ 9 ］ invention, layer is sealed in the heat-sealing of side below that is positioned at anti-adhesion layer, by containing ethene-beta-unsaturated esters copolymer, fusing point, be that 80 ℃ of above waxes and the resin combination of tackifier form, wherein, by using its softening point, be 90 ℃ of above resin combinations, can improve the resistance to effect of heat of anti-adhesion layer, improve significantly the heat stability of its anti-adhesion performance, container body is being sealed after use, also can maintained well the above-mentioned excellent content adhesion effect that prevents.

Stable on heating raising effect like this, according to the inventor's investigation, thinks to reach by following phenomenon.; be arranged at heat-sealing and seal the pass that the anti-content adhesion layer of the outside face of layer forms by hydrophobic wet silicon dioxide particle layer and fasten with additional; even if the heat affectings that are directly subject to from hot plate when the radiant heat from hot plate being subject in the standby during seal of vessel after the heating during by dry after this silicon dioxide granule dispersed liquid coating or content are filled and heat-sealing etc., also can suppress or prevent low melting point composition in resin combination in early days and exceedingly melting and present high flow.That is, high by the softening point of resin combination, can make its melting postpone, can suppress its melting in addition.Its result, can prevent: the hydrophobic wet silicon dioxide particle of anti-adhesion layer by mistake sinks to heat-sealing and seals in layer, or the molten component that layer is sealed in heat-sealing is because coming the above-mentioned gap of landfill in the gap that capillarity enters between silicon dioxide granule.Therefore, can think the extreme minimizing of exposing area of the hydrophobic surface that can prevent above-mentioned silicon dioxide granule, maintain the good content adhesion effect that prevents.

In ［ 10 ］ invention, the softening point of resin combination is more than 100 ℃, and the fusing point of wax is more than 90 ℃, therefore can be more conscientiously and obtain well resistance to effect of heat and improve effect.

In ［ 11 ］ invention, by as ethene-beta-unsaturated esters copolymer, employing fusing point is ethene-beta-unsaturated esters copolymer of 75～100 ℃, when can conscientiously guarantee good heat sealability, leak tightness, the suitable easy fissility when breaking a seal, conscientiously guarantee the anti-content adhesion value of excellent heat stability.As the beta-unsaturated esters monomer of ethene-beta-unsaturated esters copolymer, it is the vinyl esters etc. of the esters of unsaturated carboxylic acids, vinyl acetate and so on of methyl acrylate, ethyl acrylate, methyl methacrylate etc.Be preferably ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate methyl terpolymer.

In ［ 12 ］ invention, by ethene-beta-unsaturated esters copolymer, use ethene-beta-unsaturated esters copolymer of the melting range of 70～100 ℃, and wax is used the wax of the higher melt of 80～130 ℃ of fusing points, the softening point that formation heat-sealing is sealed to the resin combination of layer is set in the scope of 90～160 ℃, does not damage thus low-temperature heat-sealing and can synthetically conscientiously reach the various effects that invent above-mentioned ［ 9 ］～［ 11 ］.

In ［ 13 ］ invention, by making to form heat-sealing, seal the resin combination of layer to have ethene-beta-unsaturated esters copolymer be that 30～50 % by weight, wax are that 30～50 % by weight, tackifier are the composition of 5～25 % by weight, can reach good heat sealability, leak tightness, the suitable easy fissility when breaking a seal and prevent the raising of the heat stability of content adhesion effect.

In ［ 14 ］ invention, because the oil absorption of hydrophobic wet silicon dioxide particle is more than 50ml/100g, therefore when layer melting sealed in heat-sealing, the ability of measuring fast and fully its contained low melting point of ground absorption, low molecular weight compositions is excellent, can fully reach the effect that resistance to effect of heat improves.The higher limit of oil absorption is not particular importance in the present invention.Enough below for oil absorption 250～350ml/100g that wet silicon dioxide has, do not need choice for use to there is the special wet silicon dioxide of its above oil absorption.Reason is to improve by causing cost bring unfavorable larger.

In ［ 15 ］ invention, by heat-sealing, sealing 90 ℃ of melt viscosities above, at 160 ℃ of layer use softening point is the resin combination below 4000mPas, improve the resistance to effect of heat of anti-adhesion layer, and the rising of heat-sealing being sealed to the melt viscosity of layer suppresses for lower, improve and be mingled with leak tightness thus, and can significantly improve the heat stability of anti-adhesion performance, to the sealing after use of container body, also can maintain well the above-mentioned excellent content adhesion effect that prevents.

The raising effect of the heat stability of anti-adhesion performance like this, according to the inventor's investigation, thinks to reach by following phenomenon.; be arranged at heat-sealing and seal the pass that the anti-content adhesion layer of the outside face of layer forms by hydrophobic wet silicon dioxide particle layer and fasten with additional; even if the heat affectings that are directly subject to from hot plate when the radiant heat from hot plate being subject in the standby during seal of vessel after the heating during by dry after this silicon dioxide granule dispersed liquid coating or content are filled and heat-sealing etc., also can suppress or prevent low melting point composition in resin combination in early days and exceedingly melting and present high flow.That is, high by the softening point of resin combination, can make its melting postpone, can suppress its melting in addition.Its result, can prevent: the hydrophobic wet silicon dioxide particle of anti-adhesion layer by mistake sinks to heat-sealing and seals in layer, or the molten component that layer is sealed in heat-sealing is because coming the above-mentioned gap of landfill in the gap that capillarity enters between silicon dioxide granule.Therefore, can think the extreme minimizing of exposing area of the hydrophobic surface that can prevent above-mentioned silicon dioxide granule, maintain the good content adhesion effect that prevents.

In addition, for hydrophobic wet silicon dioxide particle, become to be situated between and be that the heat-sealing of container body and cover piece seals the inclusion between layer, by raising, seal and seal the softening point of layer and the rising of melt viscosity is suppressed for lower, specifically, by having considered that the melt viscosity at 160 ℃ of heat-sealing temperature is suppressed at below 4000mPas, when heat-sealing, heat-sealing is sealed after layer melting, and hydrophobic wet silicon dioxide particle easily and promptly enters into this heat-sealing and seals in layer.That is, easily silicon dioxide granule being included in to heat-sealing seals in layer.Therefore, be mingled with leak tightness excellence, the temperature while not needing so to improve sealing and can sealing.That is to say, do not damage low temperature sealing.And then the softening point that can also bring into play to greatest extent thus by making heat-sealing seal layer is the raising effect of 90 ℃ of above above-mentioned heat stabilitys that bring.

In ［ 16 ］ invention, ethene-beta-unsaturated esters copolymer is used ethene-beta-unsaturated esters copolymer of the melting range of 70～100 ℃, and wax and tackifier use 80～130 ℃ of softening point or fusing points compared with the material of high softening-point or fusing point, the softening point that thus formation heat-sealing is sealed to the resin combination of layer is set in the scope of 90～160 ℃, and the melt viscosity at 160 ℃ is set in to the scope of 2000～4000mPas, thereby does not damage low-temperature heat-sealing and can synthetically conscientiously reach the various effects of above-mentioned ［ 15 ］ invention.

In ［ 17 ］ invention, heat-sealing is sealed layer and is resin, forms as resin combination that must composition with wax and/or tackifier by containing acid modified polyolefin, the fusing point of above-mentioned wax and tackifier is all more than 80 ℃, first certainly can improve by leaps and bounds thus hydrophobic wet silicon dioxide particle and seal the adherence of sealing layer, can not produce coming off, partly peeling off of anti-adhesion layer, not have the hydrophobic wet silicon dioxide particle of anti-adhesion layer to be included into the anxiety that the interior infringement of content prevents adhesion effect.Much less, tackifier composition is also having larger contribution aspect the adherence of raising hydrophobic wet silicon dioxide particle as described above to wax composition.

In addition, the above-mentioned composition of layer is sealed in heat-sealing, can improve anti-adhesion layer resistance to effect of heat, significantly improves the heat stability of its anti-adhesion performance, also maintains well the above-mentioned excellent content adhesion effect that prevents after to the heat-sealing of container body.The wax composition in layer is sealed in heat-sealing, for improving with the adherence of hydrophobic wet silicon dioxide particle, undertakes important effect, but general used wax had problems on the heat stability of adhesion effect preventing in the past.To this, the heat stability that prevents adhesion effect of the present invention, be stable on heating raising effect, according to the inventor's investigation, think to reach by following phenomenon.; be arranged at heat-sealing and seal the pass that the anti-content adhesion layer of the outside face of layer forms by hydrophobic wet silicon dioxide particle layer and fasten with additional; even if the heat affectings that are directly subject to from hot plate when the radiant heat from hot plate being subject in the standby during seal of vessel after the heating during by dry after this silicon dioxide granule dispersed liquid coating or content are filled and heat-sealing etc., also can suppress or prevent low melting point composition in resin combination in early days and exceedingly melting and present high flow.That is, all high by the wax of resin combination and/or the fusing point of tackifier, can make their melting postpone, can suppress their melting in addition.Its result, can prevent: the hydrophobic wet silicon dioxide particle of anti-adhesion layer by mistake sinks to heat-sealing and seals in layer, or the molten component that layer is sealed in heat-sealing is because coming the above-mentioned gap of landfill in the gap that capillarity enters between silicon dioxide granule.Therefore, can think the extreme minimizing of exposing area of the hydrophobic surface that can prevent above-mentioned silicon dioxide granule, maintain the good content adhesion effect that prevents.

［ 18 ］ cover piece of invention, first, the anti-adhesion layer being formed by its hydrophobic wet silicon dioxide particle, be by seal the whole face of the outside face of layer to spreading all over heat-sealing, to be formed with the male and fomale(M&F) of the most microspike below height 100 μ m, hydrophobic property wet silicon dioxide particle forms.Therefore, in the painting process of the dispersion liquid of hydrophobic wet silicon dioxide particle, by above-mentioned microspike, prevent from flowing on the face of dispersion liquid, liquid sagging, can easily form the uniform anti-adhesion layer of distribution of particles.That is, can effectively prevent the excess electron excess fraction of hydrophobic wet silicon dioxide particle or partially the existing of distribution of extremely few part etc. on the contrary.And on this basis, the adhesion amount by hydrophobic wet silicon dioxide particle is made as at least 0.05g/m ²above, can make anti-adhesion layer spread all over to have all sidedly the good content adhesion effect that prevents.

And, by the adhesion amount of the hydrophobic wet silicon dioxide particle in anti-adhesion layer, be set as the amount below the degree of the top end face that covers thinly at the most the microspike that height as described above is low, anti-adhesion layer, the part as thin as a wafer of sealing layer point-like and expose or become hydrophobic wet silicon dioxide particle layer in the part heat-sealing that has microspike, these parts exist by dense distribution with point-like on the whole.Therefore,, in heat-sealing portion, hydrophobic wet silicon dioxide particle layer becomes inclusion, can not damage significantly heat sealability, can maintain well sealing intensity, leak tightness, and can make sealing intensity substantially even, and then also can improve the stable easy fissility while breaking a seal.On the other hand, although anti-adhesion layer consists of a small amount of hydrophobic wet silicon dioxide population, but as distinguished by the contrast of embodiment described later and comparative example, spread all over and become universally hydrophobic wet silicon dioxide particle well-distributed layer, therefore can make whole face present stable necessary and fully degree prevent content adhesion effect.And, the microspike that point-like exists in anti-adhesion layer, prevent cover piece when operation and use in the coming off and peel off of silicon dioxide granule unintentionally, and prevent the generation due to the albefaction trace due to the friction of the interferences with outside, long term maintenance stable prevent content adhesion effect in, maintaining of outward appearance in no way inferior, there is contribution.

In ［ 19 ］ invention, the surface of anti-adhesion layer side is formed the low-frictional force surface with specific coefficient of static friction, much less there is thus stable sliding, extraction (feed) property from platen roller, can carry out to heat-sealing portion stable the feeding smoothly of cover piece, can reduce the generation by the operation fault due to the supply mistake of cover plate, even in a series of operation before heat-sealing, for the demonstration printing stamping-out corresponding to each cover plate, be in the situation of cover piece of the stamping-out type used of unit cover plate, can not cause the spacing skew of printing position and stamping-out position yet, can carry out the Blanking Shaping of stable good unit cover plate.

Moreover in this manual, softening point is to obtain by ball-and-ring method (according to JIS K6863 " the softening point test method of hotmelt "), fusing point is to obtain by DSC method (according to JIS K7121 " the transition temperature measuring methods of plastics ").

Accompanying drawing explanation

Fig. 1 means the section drawing of the summary that the lamination that prevents the cover piece that content adheres to of the present invention forms.

The specific embodiment

Fig. 1 represents an example of the lamination formation that prevents the cover piece that content adheres to that the present invention's (the 1st, 2 invention) relates to.This cover piece, there is the substrate layer (1) that the lamination by base material rete (2) and metal foil layer (3) forms, and at the outside face of metallic paper (3) side of this substrate layer (1), when executing lid and use, on the face of a side of the inside of container body, across middle resin layer (4), be provided with heat-sealing and seal layer (5).Above-mentioned lamination forms, and same with the lamination of cover piece in the past, at this, the laminated body of substrate layer (1)/middle resin layer (4)/heat-sealing being sealed to layer (5) is called " cover piece main body ".

What the present invention relates to prevents the cover piece that content adheres to, and is the cover piece that the outside face that seals layer (4) in the heat-sealing of above-mentioned cover piece main body also additionally has anti-adhesion layer (6).

Base material rete (2) is disposed at the table side of packing container, as its material, can illustration polyester, the individual layer of polyethylene, polypropylene, polyamide, polyacrylates, polycarbonate, polyvinylchloride, cellulose ethanoate, glass paper etc. or complex film or laminated body that these films, laminated resin are formed in paper etc. etc.Base material rete (2) is suitably implemented printing (7) conventionally, is endowed designability.

Metal foil layer (3) is the layer of giving barrier properties for gases, light-proofness etc., mostly uses aluminium foil.In the cover piece of particularly using at the container of coffee beverage and Yoghourt, as the metal foil layer that meets light-proofness, light weight, the preferred aluminium foil of used thickness 5～100 about μ m.In addition, use general adhesives with base material rete (2) stacked bonding.

Moreover, as substrate layer (1), also can not use metal foil layer (3) and use the metal evaporation of silicon dioxide, aluminium oxide etc. in the metal steam plated film of base material rete (2).

Middle resin layer (4), is to be situated between to be that substrate layer (1) and heat-sealing seal between layer (5), the rigidity that cover piece stipulate and/or the resiliency when sealing layer, suitably setting as required.The olefin resin of polyethylene that usually, can used thickness 5～40 μ m, polypropylene, ethene-(methyl) acrylic copolymer, ethene-(methyl) acrylate copolymer etc., polyamide, polyester, polycarbonate, polyvinylchloride etc.

Layer (5) is sealed in heat-sealing, so long as the layer good with the gleyness of interlayer resin bed (4) and vessel side, its material is not particularly limited, but particularly in the cover piece of the wrapping paper/polyethylene cans such as Yoghourt, general preferred use hotmelt.In addition, among hotmelt, wish to use that to take wax and ethene-beta-unsaturated esters copolymer be major component, its surplus is the tackifier of rosin etc., so wish to use by contain 30 % by weight above, preferably contain more than 40 % by weight ethene-beta-unsaturated esters copolymer for example the thermoplastic resin of ethylene-vinyl acetate copolymer form the hotmelt minute forming.That is, in the hotmelt of the amount of ethene-beta-unsaturated esters copolymer lower than 30 % by weight, as the wax of low melting point composition and the amount of rosin, relatively increase, therefore according to experimental result, reduce the stable on heating tendency grow of anti-adhesion layer.Its reason infer be because, the hot impact being subject to when dry and/or during heat-sealing, the melting of above-mentioned low melting point composition, the quantitative change being adsorbed on hydrophobic wet silicon dioxide particle is many, and then the hydrophobic surface that reduces this particle is long-pending, likely make to prevent that adhesion effect from reducing.

The thickness that seals layer about heat-sealing, is not particularly limited, but from the viewpoint of cost, leak tightness, productivity etc., is generally made as thickness 3～100 μ m left and right, is preferably the scope of 10～50 μ m.

［ explanation of the anti-adhesion layer in the 1st invention ］

Form the anti-adhesion layer (6) of the main composition key element of the 1st invention, it is characterized in that, adopt following wet silicon dioxide particle to form, described wet silicon dioxide particle is: the surperficial hydroxy chemical that organo-silicon compound are wet silicon dioxide particle with the synthetic amorphous silica of being manufactured by damp process is reacted, thereby given hydrophobic hydrophobic wet silicon dioxide particle, and especially polysiloxane more than viscosity 100cst has been carried out to hydrophobization processing for the treatment of agent.The present invention, by use, adopt polysiloxane more than such viscosity 100cst to carry out the hydrophobic wet silicon dioxide particle that hydrophobization is processed, can provide and can make this particle self with high hydrophobic, even and if then also there is the cover piece of high anti-content tack under few coating weight.

Its reason is presumed as follows.

First, by using wet silicon dioxide particle, this particle is more at fabrication phase surface silicon alcohol radical, and then this surface has been carried out, in the situation of hydrophobization processing, compare with dry type silicon dioxide, generally shows excellent hydrophobic nature, hydrophobic.; with take inside not the agglomerate of the punctulate primary particle of tool be that the dry type silicon dioxide granule that offspring is least unit is compared, not only particle diameter is large, and in inside, has most minute aperture of including air in; specific surface area with respect to particle diameter is large, and pore volume is also large.Therefore, hydrophobic wet type particle, the effect by the hydrophobic group that carried out on surface replacing and the synergy of effect of bringing the air of minute aperture into, bring into play excellent hydrophobic nature, hydrophobic.

In addition, in this 1st invention, hydrophobization inorganic agent as wet silicon dioxide particle, be used as especially main framing to there is the polysiloxane of the poly-mer of siloxane bond, and use to adopt viscosity to carry out hydrophobization processing for polysiloxane more than 100cst, thus, as anti-adhesion layer, form material, can become the material that performance is more excellent.

Kind as polysiloxane, is not particularly limited, for example, also can use hydrogenated methyl diene polysiloxane, but from the viewpoint of the easiness processed, cost etc., the dimethyl polysiloxane that recommendation is the most general.

At this, the viscosity of this polysiloxane is made as to reason more than 100cst, be the item of trying to achieve from experimental result, as its mechanism, can consider as follows.

That is, wet silicon dioxide particle, in situation about having been processed by polysiloxane hydrophobization, is not that whole hydrophilic group (silanol base) on its surface is replaced by hydrophobic group, at the remaining silanol base of a surperficial part yet.This remaining silanol base is wetting ability, therefore originally just to hydrophobic nature, gave harmful effect, but in the situation that more than the viscosity of polysiloxane is made as to 100cst, the strand of the hydrophobic group replacing is long in preferred scope, can with suitable scope, be covered by this strand the surface of remaining silanol base.Thus, can think and can make the surperficial hydrophobization Du Genggao of wet silicon dioxide particle.In fact, when the viscosity of polysiloxane is during lower than 100cst, can not obtain obtaining the hydrophobization effect of fully satisfied degree.Inferring this is because the strand of the hydrophobic group that replaces is short, does not therefore fully cover due to the surface of remaining silanol base.

But, on the other hand, in the situation that the viscosity of polysiloxane surpasses 2000cst, instead show surface hydrophobicity, reduce tendency.Can think that this is due to following reason: more than the strand of hydrophobic group is crossed and grown to and need, it covers the minute aperture of particle surface, and the particle that becomes can not be included air in, result, the hydrophobic effect being brought by air can not be given full play to.

From investigation as described above, for the viscosity of the polysiloxane of hydrophobizers, be necessarily more than 100cst, to be preferably below 2000cst, the scope of 200～1000cst more preferably.

The particle diameter of the hydrophobic wet silicon dioxide particle using in the 1st invention, is preferably used the hydrophobic wet silicon dioxide particle of the scope of mean grain size 0.5～7.0 μ m.

While using mean grain size lower than the particulate of 0.5 μ m, under the scope that roughly heat sealability is not caused the such few coating weight of harmful effect, adhesion amount, can not obtain the good content adhesion effect that prevents.While use surpassing on the contrary the such thick particle of 7.0 μ m, the adherence variation of not only sealing layer (5) with heat-sealing, and infringement heat sealability.Preferably using mean grain size is the particulate of the scope of 2.0～5.0 μ m.

In addition, the adhesion amount (coating weight) of the above-mentioned hydrophobic wet silicon dioxide particle in anti-adhesion layer (6), is set at 0.1～1.0g/m ²scope, preferably set at 0.4～0.6g/m ²scope.When the adhesion amount of hydrophobic wet silicon dioxide particle is lower than above-mentioned lower limit 0.1g/m ²time, can not obtain the good content adhesion effect that prevents.And when adhesion amount is over above-mentioned higher limit 1.0g/m ²time, prevent that content adhesion effect is saturated, on the other hand, the heat sealability of layer (5) is sealed in anti-adhesion layer (6) infringement heat-sealing, specifically, compare with the situation without anti-adhesion layer (6), sealing intensity (peel resistant strength) reduces more than 20%, the anxiety that has the leak tightness of stable good container to be compromised.Moreover, with heat-sealing seal layer (5) adherence also reduce.

［ explanation of the anti-adhesion layer in the 2nd invention ］

Form the anti-adhesion layer (6) of the main composition key element of the 2nd invention, it is characterized in that, adopt following wet silicon dioxide particle to form, described wet silicon dioxide particle is: the surperficial hydroxy chemical that organo-silicon compound are wet silicon dioxide particle with the synthetic amorphous silica of being manufactured by damp process is reacted, thereby given hydrophobic hydrophobic wet silicon dioxide particle, and especially to heavens hydrophobization processed so that DBA adsorbance (di-n-butyl amine adsorbance) for below 200mmol/kg.The present invention is by using such hydrophobization to be treated to the hydrophobic wet silicon dioxide particle below DBA adsorbance 200mmol/kg, can provide this particle self with high hydrophobic nature, and then under its few coating weight, there is the cover piece of high anti-content adhesion value.

Its reason is presumed as follows.

First, by using wet silicon dioxide particle, this particle is more at fabrication phase surface silicon alcohol radical, and then this surface has been carried out, in the situation of hydrophobization processing, compare with dry type silicon dioxide, generally shows excellent hydrophobic nature, hydrophobic.; with with inside not the dry type silicon dioxide granule of the agglomerate of the punctulate primary particle of tool compare, wet silicon dioxide particle not only its particle diameter is large, and in inside, has most minute aperture of including air in; specific surface area with respect to particle diameter is large, and pore volume is also large.Therefore, hydrophobic wet silicon dioxide particle, the effect by the hydrophobic group that carried out on surface replacing and the synergy of effect of bringing the air of minute aperture into, bring into play excellent hydrophobic nature, hydrophobic.On this basis, in the present invention, by using and then wet silicon dioxide particle himself shows the hydrophobic wet silicon dioxide particle that the height hydrophobization of the value below DBA adsorbance 200mmol/kg has been processed, shows higher hydrophobic nature, performance is the anti-adhesion performance of excellence further.

At this, in this 2nd invention, the DBA adsorbance of the hydrophobic degree of expression wet silicon dioxide particle is defined as 200mmol/kg and based on experimental result, stipulates below.That is,, in the situation that use the hydrophobic wet silicon dioxide particle of the DBA adsorbance that surpasses 200mmol/kg, under few coating weight, can not make the good anti-adhesion performance of anti-adhesion layer performance.On the other hand, while making coating weight many, silicon dioxide granule self seals the adherence variation of layer with respect to heat-sealing for this reason, and the possibility that the particle that produces anti-adhesion layer comes off, part is peeled off increases.

But wet silicon dioxide particle, processes even if implement as described above sufficient hydrophobization, is not also that surperficial the whole of hydrophilic group are replaced by hydrophobic group, inevitably remaining wetting ability silanol base to a certain degree.This remaining silanol base, although the hydrophobic nature of being helpless to, the wetting ability having by it, poor to the affinity of molten resin composition, this contributes to guarantee the heat-resistant stability of anti-adhesion layer on the contrary.; the high heat affecting being subject to from Re Tai during pressure heat drying after forming by anti-adhesion layer coating or during heat-sealing; heat-sealing seal layer the melting of low melting point composition, fluidization time; also can prevent to a certain degree: above-mentioned molten resin becomes to grade and is penetrated into the small internal voids of gap between the silicon dioxide granule that forms anti-adhesion layer and particle self, cover the reduction of the anti-adhesion performance that the hydrophobic surface of particle causes because of capillarity, contribute to resistance to effect of heat to improve thinking aspect this.In view of this, DBA adsorbance, considers in the situation of relation of the difficulty of manufacturing with hydrophobic silica, shows that value more than 30mmol/kg is more suitable.Therefore, the scope of the preferred DBA adsorbance of hydrophobic wet silicon dioxide is 30～100mmol/kg.

In addition, the particle diameter of the hydrophobic wet silicon dioxide particle using in the 2nd invention, wishing to use mean grain size is that 6.0 μ m are following, particularly preferably to use mean grain size be the hydrophobic wet silicon dioxide particle of the scope of 0.2～5.0 μ m.

While using mean grain size to surpass the such thick particle of 6.0 μ m, the adherence variation of not only sealing layer (5) with heat-sealing, and produce infringement heat sealability probably.On the other hand, while using the little particle lower than 0.2 μ m, roughly to heat sealability, do not causing the scope of the such few coating weight of harmful effect, adhesion amount can not obtain the good content adhesion effect that prevents.Preferably using mean grain size is the hydrophobic wet silicon dioxide particle of the scope of 2.0～5.0 μ m.

In addition, the adhesion amount (coating weight) of the above-mentioned hydrophobic wet silicon dioxide particle in anti-adhesion layer (6), is set at 0.1～1.0g/m ²scope, preferably set at 0.2～0.5g/m ²scope.When the adhesion amount of hydrophobic wet silicon dioxide particle is lower than above-mentioned lower limit 0.1g/m ²time, can not obtain the good content adhesion effect that prevents.And when adhesion amount is over above-mentioned higher limit 1.0g/m ²time, prevent that content adhesion effect is saturated, on the other hand, the heat sealability of layer (5) is sealed in anti-adhesion layer (6) infringement heat-sealing, specifically, compare with the situation without anti-adhesion layer (6), sealing intensity (peel resistant strength) reduces more than 20%, the anxiety that has the leak tightness of stable good container to be compromised.Moreover, with heat-sealing seal layer (5) adherence also reduce.

Below the 1st invention, the common explanation of the 2nd invention.

In the manufacture of the cover piece relating in the present invention's (the 1st, 2 invention), the formation of anti-adhesion layer (6) is carried out by the following method: first, be modulated at the dispersion liquid that has disperseed hydrophobic wet silicon dioxide particle in organic solvent with normal concentration, the outside face of layer (5) is sealed in the heat-sealing of being coated in cover piece main body.

The solvent that is used for the modulation of dispersion liquid, seals stationarity, the tack of layer (5), preferably with an organic solvent for the heat-sealing of substrate in order to ensure hydrophobic wet silicon dioxide particle.Particularly preferably use the organic solvent with polar group.Wherein, it is suitable using alcohols, particularly from the viewpoint of cost, safety, hydrophobic nature present effect etc., use ethanol and/or methyl alcohol are more suitable.

The dispersion concentration of the silicon dioxide granule in dispersion liquid, can consider at random to set with the relation of the coating weight of this particle, but lower than 2%(silicon dioxide granule 2g: in the time of solvent 100ml), be difficult to realize the even coating of the silicon dioxide granule of abundant amount, when being while surpassing 10% high concentration, it is superfluous that coating weight easily becomes.Suitable dispersion concentration is roughly 3～6% left and right.

The coating means of dispersion liquid, can adopt known method arbitrarily.For example, can at random adopt gravure roll rubbing method, winding-up coating, excellent rubbing method etc. winds the line.

The coating weight of dispersion liquid, much less, should be the coating weight corresponding with the adhesion amount of hydrophobic wet silicon dioxide particle as described above in anti-adhesion layer (5).

Then, after above-mentioned working procedure of coating, cover piece main body, for drying process, is made to apply solvent in dispersion liquid and waves loosely, form the desired anti-adhesion layer (6) of hydrophobic wet silicon dioxide particle well-distributed of dry specified amount.This is dry can be natural seasoning, but in order to improve operating efficiency and hydrophobic wet silicon dioxide particle and heat-sealing, seals the adherence of layer (5), preferably by compulsory heat drying, is undertaken.Heating condition is now not particularly limited, but should be set as 80～140 ℃ of temperature, is preferably 100～120 ℃, 5～30 seconds time, is preferably about 10～20 seconds.Temperature is during lower than 80 ℃ of above-mentioned lower limits, drying process spended time, and the time is during lower than 5 seconds, dryly becomes insufficient, in operation thereafter, easily produces the peeling off, come off of part of anti-adhesion layer.And when baking temperature being set as surpass the high temperature of 140 ℃ or the time is set as surpassing the time of 30 seconds, have the surface hydrophobic that hydrophobic wet silicon dioxide particle has, the anxiety that hydrophobic nature is compromised.

［ explanation of the suitable formation of layer is sealed in heat-sealing ］

In the present invention's (the 1st, 2 invention), as heat-sealing, seal layer (5), be preferably following such formation.

Layer (5) is sealed in heat-sealing, necessary good with the gleyness of interlayer resin bed (4) and vessel side.Above-mentioned heat-sealing is sealed layer (5) and preferably following resin combination, is consisted of, described resin combination contains ethene-beta-unsaturated esters copolymer, wax and tackifier as essential composition, also contains as required the additive of anti blocking agent, oxidation inhibitor etc. as any composition.

Use the resin combination of this composition to seal layer as heat-sealing, this is as in the past known, but general this general resin combination in the past, and wax that must composition as it, has been used the wax compared with low melting point.For example, the most usually use the paraffin of 65 ℃ of left and right of fusing point, even the Tissuemat E of higher fusing point is the wax using to 75 ℃ of left and right of high melting point only.And above-mentioned resin combination has generally been used the resin combination of 65 ℃ of softening points～90 ℃ of left and right.

In the present invention, wax as one of essential composition of above-mentioned resin combination, use especially 80 ℃ of fusing points above, be preferably 90 ℃ of above, 100 ℃ of above waxes more preferably, the softening point that makes resin combination be 90 ℃ above, be preferably 100 ℃ above, more preferably more than 105 ℃.The resin combination of softening point being set highlyer by the wax that contains such higher melt seals layer for heat-sealing, can significantly improve as described above thus in heat-sealing and seal the additional hydrophobic nature of anti-adhesion layer forming of outside face side of layer and the heat stability that adheres to preventive.

But the use of the wax that fusing point is too high, can cause the viscosity of resin combination to uprise, there is the anxiety of processing suitability reduction, the anxiety that has infringement heat-sealing to seal the stable good heat sealability of layer, is therefore preferably used 130 ℃ of following waxes of fusing point.More preferably use 120 ℃ of following waxes of fusing point, particularly preferably use 110 ℃ of following waxes of fusing point.

In addition, the softening point of above-mentioned resin combination, by other the composition beyond wax, use fusing point or the high material of softening point, also can improve above-mentioned softening point, but the fusing point by making wax is with above-mentioned, the softening point of resin combination is set as more than 90 ℃, can realizes the simplest and easy and effectively desired effect.

Even if improve the softening point of resin combination by improving the fusing point of resin, the wax of the low melting point that flowing power is high is easily fusing also, enter between the hydrophobic particulate of anti-adhesion layer, make to prevent that adhesion effect from reducing, therefore preventing that on the heat stability of adhesion effect, being difficult to expectation has the sufficient effect of improving.

In addition, the use of the resin combination that softening point is too high, has infringement heat-sealing to seal the processibility of layer and the anxiety of stable good heat sealability, therefore preferably uses 160 ℃ of following resin combinations of softening point.More preferably use 140 ℃ of softening points below, particularly preferably to use 120 ℃ of following resin combinations.

As heat-sealing, seal ethene-beta-unsaturated esters copolymer of the essential composition of layer, as its beta-unsaturated esters monomer, can use the vinyl esters of the esters of unsaturated carboxylic acids such as methyl acrylate, ethyl acrylate, methyl methacrylate, vinyl acetate and so on etc., wherein, particularly preferably adopt vinyl acetate, methyl methacrylate.

In addition, above-mentioned ethene-beta-unsaturated esters copolymer, preferably using fusing point is ethene-beta-unsaturated esters copolymer of the scope of 70～100 ℃.When its fusing point is during lower than 70 ℃, the seal temperature that seals layer due to heat-sealing is too low, therefore has the anxiety of the heat stability reduction that prevents adhesion effect of anti-adhesion layer.On the contrary, when its fusing point surpasses 100 ℃, low-temperature heat-sealing suffers damage, and sealing speed is slack-off, and operating efficiency when actual content is filled sealing reduces.Most preferably fusing point is the scope of 75～95 ℃.

In addition, wax as the essential composition in resin combination, can enumerate paraffin, ceresine wax, montan wax, f-t synthetic wax (Fischer-Tropsch wax), Tissuemat E, polypropylene wax, carnauba wax, modified waxes etc., more preferably Tissuemat E.

In addition, as tackifier, can enumerate rosin, rosin derivative (Foral, non-homogenizing rosin, rosin ester), alicyclic through-stone oleoresin, aromatic through-stone oleoresin, Copolymer petroleum resin or their hydrogen affixture, terpene resin (australene, nopinene) etc., preferably use the hydrogen affixture of aromatic through-stone oleoresin, this is best.

In addition, the mix proportion ratio of the essential composition of resin combination, need to consider softening point, melt viscosity, low-temperature heat-sealing, heat seal strength, Kaifeng intensity etc. is set, by ethene-beta-unsaturated esters copolymer is preferably set to 30～50 % by weight, more preferably be set as 35～45 % by weight, wax is preferably set to 30～50 % by weight, more preferably be set as 35～45 % by weight, tackifier are preferably set to 5～25 % by weight, more preferably be set as 15～25 % by weight, can reach good heat sealability, leak tightness, suitable easy fissility while being used for breaking a seal and the raising that prevents the heat stability of content adhesion effect.That is, the use level of ethene-beta-unsaturated esters copolymer, lower than the resin combination of 30 % by weight, can not get sufficient sealing intensity, therefore not preferred.If contrary, surpass 50 % by weight, sealing intensity is excessive, and the easily openable of seal cover cap suffers damage, therefore not preferred.In addition, the use level of wax is during lower than 30 % by weight, and the coating suitability of thermoplastic resin composite (processing suitability) suffers damage, and easily openable suffers damage, therefore not preferred.On the other hand, when surpassing 50 % by weight, can not get sufficient sealing intensity, therefore not preferred.In addition, tackifier, when its use level is during lower than 5 % by weight, are difficult to obtain sufficient sealing intensity, surpass 25 % by weight on the contrary and too much containing sometimes, likely the adhesion effect that prevents of anti-adhesion layer reduces, therefore not preferred.

Embodiment

［ the 1st inventive embodiment ］

Then, be depicted as various experimental examples and the result thereof of confirming the effect of the 1st invention and carrying out.

(making of cover piece main body)

As base material film (2), the polyethylene terephthalate film of used thickness 12 μ m, in its one side, utilizes the aluminium foil (3) of polyurethane series dry lamination adhesives coating thickness 30 μ m, forms substrate layer (1).

Then, on the surface of aluminium foil (3) side of above-mentioned substrate layer (1), utilize the polyethylene film with the stacked bonding thickness 20 μ m of above-mentioned same adhesives, form middle resin layer (4), and then in its outside, adopt gravure roll rubbing method to form heat-sealing and seal layer (5).Substrate layer (1)/middle resin layer (the 4)/heat-sealing that obtains thus of usining is sealed the laminated body of layer (5) as cover piece main body.At this, as above-mentioned heat-sealing, seal layer (5), use the hotmelt forming that forms by ethylene-vinyl acetate copolymer 55 % by weight/wax 40 % by weight/tackifier (rosin) 5 % by weight, coating weight is made as 18g/m ².

(formation of anti-adhesion layer)

As the hydrophilic wet silicon dioxide particle of being manufactured by damp process, used the silicon dioxide granule (trade name " サイロホー PVC ッ Network 200 ") of mean grain size 2.7 μ m.

On the other hand, as hydrophobization inorganic agent, 6 kinds of dimethyl polysiloxanes that viscosity is adjusted to respectively 50cst, 100cst, 200cst, 1000cst, 2000cst, 2500cst have been prepared.

And, use above-mentioned various dimethyl polysiloxane, above-mentioned wet silicon dioxide particle is carried out to hydrophobization processing according to conventional approach respectively, make the 6 kind hydrophobic wet silicon dioxide particles corresponding with above-mentioned inorganic agent viscosity.

Then, by above-mentioned various hydrophobic wet silicon dioxide particles, all with 5% dispersion concentration, be scattered in alcohol solvent, modulate various dispersion liquids, the outside face of layer (5) is sealed in the above-mentioned heat-sealing that adopts gravure roll rubbing method that these various dispersion liquids are coated on to cover piece main body with the various coating weight of the scope of 0.1～1.0g/m2 as shown in table 1,2, then force drying, obtains sealing in heat-sealing the various samples that are formed with the anti-content adhesion layer (6) consisting of above-mentioned hydrophobic wet silicon dioxide particle on layer (5).Moreover the coating weight shown in table 1,2, all means the coating weight of the part by weight of dried hydrophobic wet silicon dioxide particle.

(ranking test)

Then, each sample has been carried out to following ranking test.

(1) anti-adhesion performance

To the back side of the cover piece of each sample, be on the outside face of anti-adhesion layer, as the drop of about 0.5cc アロエヨーグ Le ト (the gloomy Yoghourt forever: Aloe Yoghurt) (MORINAGA MILK INDUSTRY Co., LTD.'s trade mark processed " the gloomy ロ of ア forever エヨーグ Le ト ") that drips, above-mentioned drop when mensuration gently tilts sample " angle of inclination while starting to roll ", evaluates judgement by following benchmark.

◎ ● ● ● below 15 degree

Zero ● ● ● below above 30 degree of 16 degree

△ ● ● ● below above 45 degree of 31 degree

* ● ● ● more than 46 degree

(2) adherence

The counterweight (500g) that vertically mounting has been wound around black cloth on the face of the anti-adhesion layer of the cover piece of each sample, gently carries out the friction of length 200mm, and visual inspection is attached to the silica volume of cloth.

Then, the transfer adhesion amount (overburden amount) of the hydrophobic wet silicon dioxide on black cloth is pressed to following metewand evaluation.

◎ ● ● ● substantially do not adhere to

Zero ● ● ● there is a little adhere to of the permissible range of being confirmed to be in

△ ● ● ● there are some to adhere to

* ● ● ● there is obvious many adhering to

The anti-adhesion benchmark test of above-mentioned (1) the results are shown in table 1, the adherence ranking test of above-mentioned (2) the results are shown in table 2.

Table 1

Table 2

First, as shown in the test results of " the anti-adhesion performance " of table 1, the hydrophobization inorganic agent that is 50cst, 2500cst in the viscosity that use to adopt the dimethyl polysiloxane of hydrophobization inorganic agent has carried out in the sample of hydrophobic wet silicon dioxide particle of hydrophobization, with above-mentioned viscosity be the situation ratio of 100cst, 200cst, 1000cst, 2000cst, confirm anti-adhesion performance all poor.When being 50cst, in the situation that few especially coating weight shows the tendency that anti-adhesion performance reduces, think that this is because the strand of hydrophobic group is short, therefore can not fully cover the cause of remaining silanol base.On the other hand, when viscosity is 2500cst, also show same tendency, think this be because, more than the molecular chain length of hydrophobic group arrives and needs, it covers, stops up the surperficial micropore of silicon dioxide granule, and air is to the minimizing of including in of micropore, the impaired cause of hydrophobic effect of air.Particularly the viscosity of hydrophobization inorganic agent is near 200cst time, can obtain the best result.

In addition, as shown in the test results of " adherence " of table 2, the adherence of the hydrophobic wet silicon dioxide particle in anti-adhesion layer, in the system of all coating weights, for roughly not adhering to (coming off), maybe can seeing the degree that some adhere to, as its tendency, demonstrate coating weight fewer, the higher tendency of adherence.Can infer that this tendency is due to following reason, along with coating weight merely increases, the amount of the hydrophobic wet silicon dioxide coming off increases.Distinguish thus, the viscosity of the inorganic agent of processing for the hydrophobization of wet silicon dioxide, does not give large impact to adherence.

According to above results verification, arrive, the hydrophobic wet silicon dioxide particle that adopts viscosity 100cst polysiloxane above, that be preferably 200～2000cst to carry out hydrophobization processing by use forms anti-adhesion layer, can be at 0.1 fewer～1.0g/m of coating weight ²the sufficient anti-adhesion performance of scope performance and adherence, and then at coating weight 0.4～0.6g/m ²scope can obtain higher effect.

［ the 2nd inventive embodiment ］

Then, various experimental examples and the result thereof of carrying out in order to confirm the effect of the 2nd invention is shown.(making of cover piece main body)

Similarly operate with " making of cover piece main body " in above-mentioned the 1st inventive embodiment, obtain cover piece main body.

(formation of anti-adhesion layer)

As the hydrophilic wet silicon dioxide particle of being manufactured by damp process, different following 3 kinds of particle diameter have been prepared.

Wet silicon dioxide A mean grain size 1.7 μ m

Wet silicon dioxide B mean grain size 2.7 μ m

Wet silicon dioxide C mean grain size 6.7 μ m

Then, hydrophobization inorganic agent is used dimethyl polysiloxane, above-mentioned wet silicon dioxide A, B, C are carried out to hydrophobization processing, about every kind of particle, make and become each hydrophobic wet silicon dioxide particle of 4 kinds that the DBA of hydrophobicity index adsorbance shows the value of 30mmol/kg, 100mmol/kg, 200mmol/kg, 250mmol/kg.

Then, above-mentioned various hydrophobic wet silicon dioxide particles are all scattered in alcohol solvent with 5% dispersion concentration, modulate various dispersion liquids, adopt gravure roll rubbing method, by these various dispersion liquids with 0.05～1.5g/m shown in table 3,4 ²the above-mentioned heat-sealing that is coated on cover piece main body of the various coating weight of scope seal the outside face of layer (5), then force drying, has obtained sealing in heat-sealing the various samples that are formed with the anti-content adhesion layer (6) consisting of above-mentioned hydrophobic wet silicon dioxide particle on layer (5).Moreover the coating weight shown in table 3,4, all means the coating weight of the part by weight of dried hydrophobic wet silicon dioxide particle.

(ranking test)

Then, for each sample, carry out above-mentioned ranking test, with above-mentioned " anti-adhesion performance " and " adherence " similarly evaluated.Anti-adhesion benchmark test the results are shown in table 3, adherence ranking test the results are shown in table 4.

Table 3

Table 4

First, as shown in the test results of " the anti-adhesion performance " of table 3, anti-adhesion layer has formed materials'use and has represented that the DBA adsorbance of hydrophobic degree is in the sample of the hydrophobic wet silicon dioxide below 200mmol/kg, in coating weight (adhesion amount), is 0.1g/m ²in above situation, all give full play of excellent anti-adhesion performance.In the situation that DBA adsorbance is 250mmol/kg, even if it is a lot of that coating weight is increased, can not obtain the anti-adhesion performance that meet.In addition, the size of the particle diameter of silicon dioxide granule, does not give king-sized impact to above-mentioned performance.

In addition, as shown in the test results of " adherence " of table 4, the adherence of the hydrophobic wet silicon dioxide particle in anti-adhesion layer, in having used all systems of the hydrophobic wet silicon dioxide that DBA adsorbance is different, demonstrate roughly the good adherence of not adhering to (coming off), maybe can see the degree that some adhere to.As its tendency, demonstrate coating weight fewer, the higher tendency of adherence, in addition, when the mean grain size of silicon dioxide granule is too large, demonstrates the tendency that adherence reduces.This tendency can infer it is due to following reason, that is, along with coating weight merely increases, in addition, along with particle diameter approximately surpasses 6.0 μ m and becomes large, the amount of the hydrophobic wet silicon dioxide coming off increases.Distinguish thus, the DBA adsorbance of the hydrophobic wet silicon dioxide of wet silicon dioxide, does not give large impact for adherence.

According to above result, can confirm, by using DBA adsorbance 200mmol/kg hydrophobic wet silicon dioxide particle following, that be preferably below 100mmol/kg to form anti-adhesion layer, can be at 0.1 fewer～1.0g/m of coating weight ²the sufficient anti-adhesion performance of scope performance and adherence.

［ embodiment of the effect of bringing for confirming to adopt the formation of above-mentioned ［ 9 ］ invention ］

(making of cover piece main body)

Then,, on the surface of aluminium foil (3) side of above-mentioned substrate layer (1), adopt and above-mentioned same adhesives, the polyethylene film of stacked bonding thickness 20 μ m, form middle resin layer (4), and then in its outside, utilize gravure roll rubbing method to form heat-sealing and seal layer (5).The laminated body that the substrate layer obtaining thus (1)/middle resin layer (4)/heat-sealing is sealed to layer (5) is as cover piece main body.

At this, as above-mentioned heat-sealing, seal layer (5), adopt following material to prepare the resin combination of the various cooperations shown in aftermentioned table 5.

Wax (WX)

WX(I): the Tissuemat E that fusing point is 108 ℃

WX(II): the Tissuemat E that fusing point is 104 ℃

WX(III): the Tissuemat E that fusing point is 94 ℃

WX(IV): the microcrystalline wax that fusing point is 80 ℃

WX(V): the paraffin that fusing point is 75 ℃

WX(VI): the paraffin that fusing point is 67 ℃

Resin (EVA)

EVA(I): 76 ℃ of ethylene-vinyl acetate copolymer (vinyl acetate amount 26%), fusing points

EVA(II): 82 ℃ of ethylene-vinyl acetate copolymer (vinyl acetate amount 20%), fusing points

EVA(III): 105 ℃ of ethylene-vinyl acetate copolymer (vinyl acetate amount 5%), fusing points

Tackifier (TF)

TF(I) petroleum hydrogenated resin

TF(II) rosin

Then, adopt gravure roll rubbing method by the thermoplastic resin composite of the various compositions shown in table 5 all with coating weight 18g/m ²ratio to be coated on above-mentioned middle resin layer (4) upper, formed heat-sealing and sealed layer (5).(formation of anti-adhesion layer)

As the material of anti-adhesion layer, following hydrophobic inorganic particles and thermoplastic resin particle have been prepared.

Hydrophobic inorganic particles (SP)

SP(I): hydrophobic dry type silicon dioxide primary particle mean grain size 7nm

SP(II): hydrophobic wet silicon dioxide mean grain size 2700nm

SP(III): hydrophobic wet silicon dioxide mean grain size 3900nm

Thermoplastic resin particle (MP)

MP(I): ethylene-vinyl acetate copolymer (vinyl acetate 20%, ethene 80%, mean grain size 100nm)

MP(II): vinyl acetate-vinyl chloride copolymer (vinyl acetate 20%, vinyl chloride 80%, mean grain size 100nm)

Above-mentioned each hydrophobic inorganic particles (SP) or hydrophobic inorganic particles (SP) are dispersed in ethanol with this two side of themoplasticity particulate (MP), have made coating fluid.The mixing ratio of the use level of hydrophobic inorganic particles or themoplasticity particulate and hydrophobic inorganic particles is shown in table 5.

Then, by these various coating fluids, the outside face of layer (5) is sealed in the above-mentioned heat-sealing that adopts gravure roll rubbing method to be coated on cover piece main body (1), and force drying, has formed anti-adhesion layer.Moreover coating weight is set as 0.5g/m in sample No.1～14 and 17～21 ²(weight after dry) is set as 0.8g/m in sample No.15,16 ²(weight after dry).In addition, force drying is all carried out under the drying condition of 15 seconds 100 ℃ * time of temperature.

(making the kind of sample)

Among sample 1～21 by the various cover pieces shown in the above-mentioned table 5 obtaining, sample the 1～9, the 19th, changes and seals the sample that the wax, resin, the softening point that seal in layer are investigated its impact.Sample 10 is to change the sample that tackifier are investigated its impact.Sample 11～14,20～21st, changes heat-sealing and seals the sample that the mixing ratio of each composition of layer is investigated its impact.Sample the 15, the 16th, the layer that anti-adhesion layer is formed for the compound by hydrophobic inorganic particles and themoplasticity particulate, and coating weight is changed into 0.8g/m ²investigate the sample of its impact.Sample the 17, the 18th, the particle diameter that changes hydrophobic inorganic particles is investigated the sample of its impact.

(ranking test)

(1) anti-adhesion performance

To the back side of the cover piece of each sample No.1～21, be on the outside face of anti-adhesion layer, as the drop of the about 0.5cc アロエヨーグ Le ト (MORINAGA MILK INDUSTRY Co., LTD.'s trade mark processed " the gloomy ロ of ア forever エヨーグ Le ト ") that drips, above-mentioned drop when mensuration gently tilts sample " angle of inclination while starting to roll ", judges evaluation by following benchmark.

◎ ● ● ● below 15 degree

Zero ● ● ● below above 30 degree of 16 degree

* ● ● ● more than 31 degree

(2) the anti-adhesion performance after heat treatment

Each cover piece for each sample No.1～21, the 1st heating test is the heating condition of " 30 seconds 100 ℃ * time of temperature ", the 2nd heating test is the heating condition of " 10 minutes 100 ℃ * time of temperature ", the 3rd heating test is the heating condition of " 15 minutes 100 ℃ * time of temperature ", for respectively each sample being cooled in heating atmosphere to each sample of normal temperature after keeping, carried out the anti-adhesion benchmark test same with above-mentioned (1).

(3) leak tightness

(sealing intensity and Kaifeng intensity)

Air-proof condition by the cover piece of sample No.1～21 with 150 ℃ * 90kgf * 1.0 second is heat sealed on the flange surface of container body (paper/polyethylene container made).

And, " seal intensity " and about the province of breast and the ingredient standard of dairy products etc., make the strength test method of sealing of (clear and on April 16th, 54 Health and human services department make No. 17) measure according to Japan, seal intensity and be 13.3kPa and be judged to be qualified (◎ symbol) when above, be judged to be nonconformity (* symbol) during lower than 13.3kPa.

Then, " Kaifeng intensity ", is that the speed of dividing with 45 °, the elevation angle, 100mm/ is carried out tractive cover piece, and the maximum load during using Kaifeng is as Kaifeng intensity (N).And, by the scope dictates of best Kaifeng intensity, be 8～15N, the sample by Kaifeng intensity within the scope of this is evaluated as qualified (◎ symbol), at this extraneous sample, is evaluated as nonconformity (* symbol).

(heat seal strength)

The cover piece of sample No.1～21 is cut into 15mm wide, with the air-proof condition of 150 ℃ * 0.2MPa * 1.0 second, be heat sealed to the wide pane of the 15mm that cuts from container body (paper/polyethylene container made).Then, the speed tractive that this cover piece is divided with 100mm/ in the direction of 180 °, the maximum load when peeling off is as heat seal strength.

And, using the heat seal strength (the peel resistant strength leak tightness of cover piece) of cover piece of cover piece subjective situation that anti-adhesion layer is not set as a reference value, by following benchmark, judge reduced rate or the increment rate of evaluation heat seal strength.

◎ ● ● ● strength decreased or increase are less than 10%

Zero ● ● ● strength decreased or increase to more than 10% and be less than 20%

* ● ● ● strength decreased or increase to more than 20%

(4) adherence

On the face of the anti-adhesion layer of each cover piece of sample No.1～21, vertical mounting has been wound around the counterweight (500g) of black cloth, gently carries out the friction of length 200mm, and visual inspection has or not the particulate that is attached to cloth surface.

Then, according to the hydrophobic particulate on black cloth and thermoplastic resin particle's transfer adhesion amount (overburden amount), by following metewand, evaluate.

◎ ● ● ● substantially do not adhere to

* ● ● ● there is obvious many adhering to

Each ranking test of above-mentioned (1)～(4) the results are shown in table 6.

As shown in the test results of " the anti-adhesion performance " of table 6, of the present invention, prevent that in cover piece that content adheres to, the Yoghourt drop that just sample tilted a little just starts to roll mobile.And, this prevents adhesion effect, as the result finding of " the anti-adhesion performance after heat treatment " test, after having stood 100 ℃ * 10 minutes and stood the quite harsh hot resume of 100 ℃ * 15 minutes, also basic not reduction, and maintained well.This demonstrates: after cover piece has been sealed in heat-sealing on the container of content of liquid component of having filled the thickness that comprises Yoghourt, pudding, fruit jelly etc., for this content, prevent that the effect of adhering to of this content on the cover piece back side is excellent.And, as shown in the result of " leak tightness " test, by the existence of anti-adhesion layer, seal intensity, heat sealability (sealing intensity) and easily openable and do not have large infringement, can maintain appropriate leak tightness and give above-mentioned anti-adhesion performance.And, as the result finding of " adherence " test, hydrophobic inorganic particulate and the adherence of anti-adhesion layer that contains it are good, the worry of do not have the separation of hydrophobic inorganic particles unintentionally etc. to come off, the part of anti-adhesion layer being peeled off etc., the anti-content adhesion value of stable maintenance chronically, and there is no foreign matter to the sorrow of sneaking in container yet.

The application is that the disclosure former state ground of above-mentioned application forms the application's a part with No. 2012-171372, Japan's patent application Patent on August 1st, 2012 application with in the application of the priority request of No. 2012-171378, Japan's patent application Patent of application on August 1st, 2012.

Term and explanation, used for embodiments of the present invention are described as used herein, and the present invention is not by its restriction.The present invention, so long as in the scope of request patent protection, can allow any design modification under the limit that does not depart from its spirit.

Description of reference numerals

1 ... substrate layer

2 ... base material rete

3 ... metal foil layer

4 ... middle resin layer

5 ... layer is sealed in heat-sealing

6 ... anti-adhesion layer

Claims

1. a cover piece that prevents that content from adhering to, at least to there is substrate layer and layer is sealed in heat-sealing, and at the outside face that layer is sealed in this heat-sealing, be provided with the heat-sealing cover piece of anti-adhesion layer, it is characterized in that, the hydrophobic wet silicon dioxide particle that described anti-adhesion layer has carried out hydrophobization processing by polysiloxane more than use viscosity 100cst forms.

2. a cover piece that prevents that content from adhering to, at least to there is substrate layer and layer is sealed in heat-sealing, and at the outside face that layer is sealed in this heat-sealing, be provided with the heat-sealing cover piece of anti-adhesion layer, it is characterized in that, described anti-adhesion layer is that hydrophobic wet silicon dioxide particle below 200mmol/kg forms by di-n-butyl amine adsorbance.

3. the cover piece that prevents that content from adhering to according to claim 1, the di-n-butyl amine adsorbance of described hydrophobic wet silicon dioxide particle is below 200mmol/kg.

4. according to the cover piece that content adheres to that prevents described in claim 1 or 3, for the viscosity of the described polysiloxane of hydrophobization inorganic agent, be below 2000cst.

5. according to the cover piece that content adheres to that prevents described in claim 1 or 3, for the described polysiloxane of hydrophobization inorganic agent, be dimethyl polysiloxane.

6. according to the cover piece that content adheres to that prevents described in claim 2 or 3, the di-n-butyl amine adsorbance of described hydrophobic wet silicon dioxide particle is 30～100mmol/kg.

7. according to the cover piece that content adheres to that prevents described in any one of claim 1～3, the coating weight of the hydrophobic wet silicon dioxide particle in described anti-adhesion layer, counts 0.1～1.0g/m to be dried rear weight ².

8. according to the cover piece that content adheres to that prevents described in any one of claim 1～3, the mean grain size of described hydrophobic wet silicon dioxide particle is 0.5～7.0 μ m.

9. according to the cover piece that content adheres to that prevents described in any one of claim 1～3, described heat-sealing is sealed layer and is formed as resin combination that must composition by containing ethene-beta-unsaturated esters copolymer, wax and tackifier, the softening point of described resin combination is more than 90 ℃, and the fusing point of described wax is more than 80 ℃.

10. the cover piece that prevents that content from adhering to according to claim 9, the softening point of described resin combination is more than 100 ℃, and the fusing point of described wax is more than 90 ℃.

11. cover pieces that prevent that content from adhering to according to claim 9, the fusing point of described ethene-beta-unsaturated esters copolymer is 70～100 ℃.

12. according to the cover piece that content adheres to that prevents described in any one of claim 1～3,

Described heat-sealing is sealed layer and is formed as resin combination that must composition by containing ethene-beta-unsaturated esters copolymer, wax and tackifier,

The fusing point of described ethene-beta-unsaturated esters copolymer is 70～100 ℃,

The fusing point of described wax is 80～130 ℃,

The softening point of described resin combination is set to 90～160 ℃.

13. cover pieces that prevent that content from adhering to according to claim 9, is characterized in that, it is that 30～50 % by weight, wax are that 30～50 % by weight, tackifier are the composition of 5～25 % by weight that described resin combination has described ethene-beta-unsaturated esters copolymer.

14. according to the cover piece that content adheres to that prevents described in any one of claim 1～3, and the oil absorption of described hydrophobic wet silicon dioxide particle is more than 50ml/100g.

15. according to the cover piece that content adheres to that prevents described in any one of claim 1～3, and it is that resin combination below 4000mPas forms that layer melt viscosity above by 90 ℃ of softening points, at 160 ℃ are sealed in described heat-sealing.

16. according to the cover piece that content adheres to that prevents described in any one of claim 1～3,

The softening point of described wax and tackifier or fusing point are 80～130 ℃,

The softening point of described resin combination is 90～160 ℃, and the melt viscosity at 160 ℃ is 2000～4000mPas.

17. according to the cover piece that content adheres to that prevents described in any one of claim 1～3,

Described heat-sealing is sealed layer and is resin, forms as resin combination that must composition with wax and/or tackifier by containing acid modified polyolefin,

The fusing point of described wax and tackifier is all more than 80 ℃.

18. according to the cover piece that content adheres to that prevents described in any one of claim 1～3,

In described heat-sealing, seal the outside face of layer, spread all over whole the dense a plurality of microspikes that are provided with below height 100 μ m in ground,

There is the described outside face of this projection, be formed with described anti-adhesion layer,

Described anti-adhesion layer, it is above and cover a little at the most below the amount of top end face of described microspike that its adhesion amount is set to 0.05g/m2.

19. according to the cover piece that content adheres to that prevents described in any one of claim 1～3, and the surperficial coefficient of static friction of described anti-adhesion layer side is set to below 0.65.