CN102634291A

CN102634291A - Adhesive tape

Info

Publication number: CN102634291A
Application number: CN2012100212881A
Authority: CN
Inventors: 三津屋圭一; 高山雅充; 高村优一
Original assignee: Nitto Denko Corp
Current assignee: Nitto Denko Corp
Priority date: 2011-02-15
Filing date: 2012-01-31
Publication date: 2012-08-15
Also published as: KR20120093774A

Abstract

The invention aims to provide an adhesive tape which helps to prevent a laminated body accommodated in an electrochemical element from loosing, etc., thereby improving the quality of the electrochemical element. The adhesive tape is used for an electrochemical element provided with a laminated body laminated by an anode foil and a cathode foil via insulating paper immersed with an electrolyte inside a housing, and is bonded on a portion that is connected with the electrolyte for use. The adhesive tape is characterized in that the surface side of a strip-shaped subsrate is provided with a bonding agent layer, the bonding force of the bonding agent layer is below 4N/15mm relative to the back side of the layer itself, and the heat shrinkage of the layer under a temparature of 280 DEG C is below 2% along the length direction.

Description

Self adhesive tape

Technical field

The self adhesive tape that the present invention relates to use in the electrochemical element; More specifically; Relate in the electrochemical elements such as the so-called aluminium electrolutic capacitor that in housing, possesses across the duplexer that insulation paper that infiltration has electrolytic solution cascades anode foils and Cathode Foil, battery, be bonded in the position that joins with above-mentioned electrolytic solution and the self adhesive tape that uses.

Background technology

In the past, electrochemical elements such as electrical condenser, electric capacity (Capacitor) or battery were widely used as the parts that constitute electronic circuit.

This electrochemical element has usually has the insulation paper of electrolytic solution to be held on interelectrode structure infiltration; Himself requires miniaturized; On the other hand then through guaranteeing that bigger electrode area increases the accumulation of electric charge, therefore, for example; In aluminium electrolutic capacitor etc., extensively adopt the electrical condenser with following structure: anode and negative electrode adopt zonal aluminium foil; Between it, sandwich and be zonal insulation paper equally, under this state, their are reeled and form columned duplexer, and it is enclosed in housing.

This electrochemical element; For example reel lax and when interelectrode distance etc. is changed when above-mentioned duplexer produces; Electrostatic capacity can change, therefore, and usually to be wound with self adhesive tape and to make it keep the range upon range of state of duplexer around the many states of its periphery 1 circle.

In addition; Self adhesive tape uses resin strip (resin molding) as its base material more, if but will be base material with the resin strip, the coiling that has the self adhesive tape of binder layer to be used for electrical condenser, electric capacity in this banding substrate laminated fixes, when the circuit substrate that then will be equipped with these parts welds in reflow soldering furnace; For example; In high temperature reflux welding, can be heated to about 250 ℃ during high temperature, so part interior reaches a high temperature the possibility that has above-mentioned banding substrate to shrink.

When such contraction takes place, following possibility is arranged: the overlapping minimizing between the self adhesive tape, the effect of constraint duplexer descends, and the perhaps overlapping disappearance between the self adhesive tape sometimes becomes and can't carry out abundant fixed state.

To such problem, put down in writing in the following patent documentation 1 and will have the technical scheme that forms that is used for the inner member of electrical condenser by the self adhesive tape of the banding substrate of Manila hemp paper pulp or kraft pulp formations such as (dissolving pulps).

Use under the situation of this paper pulp; Can expect under the Heating temperature degree due to the above-mentioned reflow soldering, to be difficult for being affected; Also be difficult for to produce the problems such as softening, contraction of base material; Even but implement such countermeasure, and also being difficult to fully to suppress the lax of duplexer, the situation that the quality of electrochemical element improves appears being difficult to realizing in the past.

In addition; Thereby also can consider to strengthen the minimizing that suppresses the lap of self adhesive tape with the convergent force that can resist base material through the bounding force of realizing binder layer; But self adhesive tape uses with the form that binder layer is bonded in the roll coil of strip at self back side usually; Therefore when bounding force is too strengthened, to peel off required power from self back side and become big, the operation property (sticking operation property) in the time of may making this adhesive tape joining to adherend reduces greatly.

In addition, also can consider to make binder layer not be adhered to self back side by partition, but under this situation, need peel off partition during sticking operation, the result causes operating efficiency to reduce.

Need to prove; Produce lax problem about duplexer; Not being detected in the such electrochemical element of aluminium electrolutic capacitor that electrode foil and insulation paper scroll are reeled, also is the problem that has in the electrochemical element that possesses the duplexer that electrode foil and insulation paper tabular cascade.

In addition; The problem that reduces about the tackiness that possibly make because of the heating in when welding etc. with adherend; Be not detected under the coiling fixed situation that is used for duplexer, and be the total problem of all self adhesive tapes that is bonded in the inner position that joins with electrolytic solution of electrochemical element.

The prior art document

Patent documentation 1: japanese kokai publication sho 59-22316 communique

Summary of the invention

The present invention is the invention of carrying out in order to solve above-mentioned problem, and its purpose is, the lax grade and the good self adhesive tape of sticking operation property of the duplexer of the inside that can prevent to be contained in electrochemical element is provided, and then realizes that the quality of electrochemical element improves.

Above-mentioned electrochemical element is produced in batches usually, in it is made, has imported auto-plant, and the state of the roll coil of strip that above-mentioned self adhesive tape also forms with rectangular adhesive tape-wound uses.

Therefore, usually, the length direction of self adhesive tape becomes MD direction (Machine Direction).

The inventor is to lax further investigation of coiling of duplexer, and it is to prevent below the prescribed value that coiling is lax that the result finds to suppress through the percent thermal shrinkage with self adhesive tape, thereby has accomplished the present invention.

Promptly; The present invention who relates to the self adhesive tape that is used to solve above-mentioned problem is following self adhesive tape; It is used for possessing in the housing electrochemical element of the duplexer that the insulation paper that electrolytic solution arranged across infiltration cascades anode foils and Cathode Foil; Use through being bonded in the position that joins with above-mentioned electrolytic solution, it is characterized in that, possess binder layer in a face side of banding substrate; Above-mentioned binder layer is below the 4N/15mm with respect to the bounding force at self back side, and the percent thermal shrinkage under 280 ℃ is below 2% in the longitudinal direction.

Need to prove, should " with respect to the bounding force at self back side " reach the value of the method mensuration of putting down in writing among the embodiment of " percent thermal shrinkage " expression through this specification sheets of " length direction ".

According to the present invention, the percent thermal shrinkage of self adhesive tape has obtained inhibition, the generation that relaxes in the time of therefore can preventing in reflow soldering furnace etc. heating.

And, self adhesive tape of the present invention, binder layer also is below the prescribed value with respect to the bounding force at self back side, thereby sticking operation property is good.

That is,, can provide sticking operation property good self adhesive tape, and then can prevent the lax etc. of duplexer that electrode foil and insulation paper form, can realize that the quality of electrochemical element improves according to the present invention.

Description of drawings

Fig. 1 is stereographic map (a) and the sectional view (b) of self adhesive tape of the self adhesive tape (roll coil of strip) of an embodiment.

Fig. 2 (a) and (b) are concise and to the point vertical views of the formation pattern of expression binder layer.

Fig. 3 is the concise and to the point vertical view of the state of the pattern of the binder layer that forms on the self adhesive tape of expression embodiment 5.

The explanation of symbol

1: self adhesive tape (roll coil of strip), 10: banding substrate, 20: binder layer

Embodiment

With reference to Fig. 1 the embodiment of self adhesive tape of the present invention is described.

Need to prove; Self adhesive tape of the present invention is except can be above at the periphery twisting cohesion of the duplexer that is formed by anode foils and Cathode Foil clamping insulation paper one circle and coiling that be used for above-mentioned duplexer fixes; Can also be widely used in the purposes that is bonded in the position that joins with electrolytic solution in the inside of electrochemical element; For example; Also can be used for repair, protection is that purpose is clipped in situation about using between electrode foil and the insulation paper, or damage when preventing to be contained in duplexer in the housing, accommodates the back is provided with distance between housing and element purposes etc.; In this embodiment, from can bringing into play the aspect of effect of the present invention more significantly, as illustration self adhesive tape of the present invention is specified with above-mentioned duplexer be used to the to reel situation of fixed-purpose.

At first, begin most, the example as the spendable purposes of self adhesive tape of this embodiment describes aluminium electrolutic capacitor.

Generally speaking; Aluminium electrolutic capacitor possesses the inner member of enclosing in the housing; The anode foils and the Cathode Foil that constitute this inner member adopt zonal aluminium foil, and the mode that under accompanying infiltration and have the state of zonal insulation paper of electrolytic solution, above-mentioned aluminium foil is scroll on the end face columned duplexer that forms of reeling is enclosed in the housing.

Need to prove,, as a rule,, use,, use the metal system housing that the round-ended cylinder shape is arranged that has than the internal diameter of the big circle of above-mentioned duplexer as above-mentioned housing with the electrolytic solution of gamma-butyrolactone as solvent as above-mentioned electrolytic solution for aluminium electrolutic capacitor.

In addition, for the inner member in the housing that is contained in aluminium electrolutic capacitor, its range upon range of state of duplexer maintenance in order to make electrode foil and insulation paper on end face, reel and form with the mode of scroll utilizes the self adhesive tape of this embodiment to fix.

Promptly; In the inner member of aluminium electrolutic capacitor; Employing is with the many bonding self adhesive tapes of mode of periphery 1 circle along the coiling direction of above-mentioned aluminium foil etc. around above-mentioned duplexer; As its member of formation, this self adhesive tape is used to be bonded in the periphery of above-mentioned duplexer, so that the coiling situation of this duplexer does not relax.

In Fig. 1 of the self adhesive tape that shows this embodiment, (a) be the reel stereographic map of the bonding roll coil of strip that forms of expression self adhesive tape 1, this bonding roll coil of strip is that the mode of the MD direction of self adhesive tape is reeled and formed with the length direction.

In addition, (b) of Fig. 1 is X-X ' the alignment pseudosection of this Fig. 1 (a), the cross-section structure of expression self adhesive tape 1.

In this embodiment, this self adhesive tape form with the roll coil of strip as shown in Figure 1 is used, and begins to draw from the outside, and is bonding and use with the periphery of above-mentioned duplexer.

Fig. 1 (b) by the cross-section structure of representing self adhesive tape 1 can find out; This self adhesive tape 1 has the rear side and inboard double-layer structure as the outside of the above-mentioned roll coil of strip; The banding substrate 10 that rear side forms by using paper pulp constitutes, in above-mentioned inboard, be that the face side of above-mentioned banding substrate 10 possesses the binder layer 20 that is formed by tackiness agent.

And in this embodiment, above-mentioned self adhesive tape 1 is through becoming web-like with the surface bonding of above-mentioned binder layer 20 to the back side (self back side) of banding substrate 10.

Because the self adhesive tape 1 of this embodiment uses with such form; Therefore; In order to draw this self adhesive tape 1 from the roll coil of strip; Will be when the bonding binder layer 20 in the back side of the banding substrate 10 of inboard be peeled off; The part of banding substrate 10 can not be destroyed and become the binder layer 20 that is attached to the self adhesive tape after peeling off the surface, be called the state that " layer break " waits, perhaps do not make to produce adhesion in the preservation, above-mentioned banding substrate 10 infiltrations are useful on the back treatment agent of the separability of the above-mentioned binder layer 20 of raising.

In addition; In the self adhesive tape 1 of this embodiment; The percent thermal shrinkage of the band under 280 ℃; Be 2% following this point on the length direction of the self adhesive tape that is usually becoming the MD direction when making self adhesive tape at the coiling that suppresses above-mentioned duplexer be very important aspect lax, this percent thermal shrinkage receives the influence of banding substrate 10 easily, the therefore preferred low banding substrate of percent thermal shrinkage that adopts.

In this embodiment, from above-mentioned viewpoint, adopt the banding substrate 10 that uses paper pulp, above-mentioned banding substrate 10 is made up of so-called " paper tape ".

As this paper pulp, can enumerate Manila hemp paper pulp, wood pulp, the dissolving pulps such as kraft pulp that obtain after wood pulp is heat-treated with caustic soda etc. also can be used as the constituent material of above-mentioned banding substrate 10.

In addition, can adopt the mixed banding substrate 10 of copying paper as this embodiment of Manila hemp paper pulp and kraft pulp.

As the paper tape that constitutes this banding substrate 10, in aluminium electrolutic capacitor purposes etc., preferred thickness is 15 μ m～60 μ m.

Preferred this thickness be more than the 15 μ m be because: low excessively during less than 15 μ m as the intensity of self adhesive tape, can be detrimental to practicality.

In addition; Preferred this thickness be thinner than 60 μ m be because: when being set at the thickness that surpasses 60 μ m; Self adhesive tape 1 not only reaches superfluous intensity for desired intensity, and also increases through the diameter of inner member that this self adhesive tape 1 twisting cohesion is obtained to the duplexer.

In addition, this paper tape preferred density is 0.5g/cm ³More than.

That is, be preferably fine and closely woven high-intensity paper tape extremely to a certain degree.

Need to prove that the intensity overwhelming majority of self adhesive tape 1 is by the intensity decision of this banding substrate 10 (paper tape).

Self adhesive tape 1 in this embodiment; Preferably have above tensile strength of prescribed value and tear strength (forming the tear strength of breach) as the intensity on the MD direction; Particularly, preferably has the above tensile strength of 20N/10mm width and have the above tear strength of 8N/15mm width.

Therefore, above-mentioned banding substrate 10 preferably can make the base material of the such intensity of self adhesive tape 1 performance.

Because of the situation that binder layer is set or the back treatment agent of infiltrating makes the intensity of self adhesive tape become the value of the intensity that is lower than banding substrate can not take place usually; Therefore; Through the banding substrate that employing has the tensile strength more than the 20N/10mm width and has the tear strength more than the 8N/15mm width, also can give this characteristic more than degree to self adhesive tape 1.

Need to prove,, can measure through the method for record in [embodiment] respectively for the tensile strength or the tear strength of self adhesive tape, banding substrate.

Constitute the binder layer 20 of self adhesive tape 1 with this banding substrate 10, can utilize general tackiness agent such as acrylic adhesives, rubber adhesive, silicone based tackiness agent (pressure-sensitive adhesive) and form.

In this embodiment, need the whole surface of banding substrate 10 not formed binder layer 20 with adhesive coverage, for example as shown in Figure 2, can the mode of banding substrate 10 part exposing surfaces form binder layer 20 with from the binder layer unilateral observation time.

For example; Fig. 2 (a) is expression to the concise and to the point vertical view of the candy strip that formed by tackiness agent in a face side of banding substrate 10 state when binder layer one side is observed, and the self adhesive tape 1x shown in this Fig strip length direction shown in the symbol A in scheme makes banding substrate 10 with successive wire exposing surface.

More specifically, the self adhesive tape 1x shown in Fig. 2 (a) is with the mode of 2 lines that keep certain intervals on the width that is formed on a band face side laminating adhesive at banding substrate 10, thereby forms binder layer 20.

Therefore; Self adhesive tape 1x shown in Fig. 2 (a) have through with the mode that forms 2 lines at range upon range of 20a of tackiness agent that a face side laminating adhesive of banding substrate 10 forms, be formed with the non-laminated section 20b of tackiness agent simultaneously through above-mentioned banding substrate is formed with 3 position exposing surfaces in the width outside between range upon range of 20a of this tackiness agent.

That is, the binder layer 20 of the self adhesive tape 1x shown in Fig. 2 (a) so that the mode that the non-laminated section 20b of above-mentioned tackiness agent becomes 3 lines form.

In addition, as shown in the drawing when with reference to Fig. 2 (b) example beyond the candy strip being described equally, also can form binder layer 2 at a face side laminating adhesive of banding substrate 10 with the mode that forms dot pattern.

Need to prove; In the self adhesive tape 1y shown in Fig. 2 (b); So that range upon range of 20a of the tackiness agent of bigger circle forms the mode of dot pattern, at banding substrate 10 laminated tackiness agents, but the size of range upon range of 20a of tackiness agent, shape can change is self-evident.

For example, can form small square dot pattern and form binder layer 2, also can form and non-circular or polygonal, atypic dot pattern and form binder layer 2 with tackiness agent with tackiness agent.

In addition, it is examples of dot shaped that self adhesive tape of the present invention for example also can make the non-laminated section 20b of tackiness agent, forms binder layer with the mode that forms the pattern opposite with the pattern shown in Fig. 2 (b).

Likewise; Candy strip also can carry out various changes; Candy strip can be that 1 line or 3 modes more than the line form with range upon range of of tackiness agent; Range upon range of of the tackiness agent of wire need not into the such linear of institute's illustration among the figure thickness is changed in the longitudinal direction, perhaps makes whole crooked with same thickness.

In addition, can be the diagonal striped that has angle with respect to the length direction A of self adhesive tape, range upon range of of the tackiness agent that also can make wire extends and makes the length direction A quadrature of range upon range of of above-mentioned tackiness agent and self adhesive tape along the bandwidth direction.

In addition, also can be employed in range upon range of of tackiness agent that point-like is set between range upon range of of the tackiness agent of 2 wire and composite pattern that candy strip and dot pattern are combined, the composite pattern that can also adopt candy strip or dot pattern and other combinations of patterns to form.

When forming such pattern; For example; With being formed with under the state on surface that mask material with the same pattern of the formation pattern of the non-laminated section of tackiness agent covers banding substrate 10; The solution that forms with above-mentioned tackiness agent or with the above-mentioned tackiness agent of volatile organic solvent diluting is applied to the surface by the banding substrate 10 of aforementioned mask material covering with roller coating machine etc., perhaps sprays to get final product.

In addition; For above-mentioned binder layer 20; Preferably with after the above-mentioned banding substrate 10 (paper tape) stated the back treatment agent likewise, never be subject to the tackiness agent of the influence of electrolytic solution etc., promptly electrolytic solution is shown select in insoluble or the insoluble tackiness agent, for example; At above-mentioned electrolytic solution is under the situation of solvent with the gamma-butyrolactone, is employed in preferably that the meltage of dipping in the time of 24 hours is the tackiness agents below the 50 quality % in 23 ± 2 ℃ the gamma-butyrolactone.

Need to prove; For whether being indissoluble or the tackiness agent that is insoluble to electrolytic solution; For example, can through with self adhesive tape or sample itself (sample that for example, forms etc.) by tackiness agent itself at normal temperatures, in the used organic solvent of this electrolytic solution or electrolytic solution etc., flood diel and confirm.

In this specification sheets, " insoluble " this term is meant when implementing above-mentioned test, does not observe its dissolving; " indissoluble " this term is meant that meltage is below the 50 quality %.

If below do not specify term " insoluble ", the above-mentioned character of " indissoluble " expression.

In addition, the device of, the purposes that be used in reflow soldering furnace pass through such for aluminium electrolutic capacitor more, the tackiness agent that preferred Young's modulus does not at high temperature also change produces viscosity and reduces and make duplexer that lax situation take place to eliminate when temperature rises.

Promptly; With general environment for use temperature, for example the energy storage Young's modulus under 30 ℃ (G ') is made as under 1 the situation; Energy storage Young's modulus under preferred 150 ℃ is the tackiness agent more than 0.8 with respect to the ratio of the energy storage Young's modulus under the environment for use temperature, even also be the tackiness agent more than 0.8 at 250 ℃ of following above-mentioned ratios preferably further.

Need to prove,, can measure through the method for record in [embodiment] of subsequent paragraphs for the energy storage Young's modulus of this tackiness agent (G ').

As such tackiness agent; Can suitably use following acrylic adhesives; Wherein, contain: be used to give fusible principal monomer with lower glass transition temperatures (Tg), can give the comonomer of having of tackiness and the cohesive force second-order transition temperature higher (Tg) and the acrylic polymers that forms with monomer reaction it with the functional group that is used to regulate bridging property, tackiness than above-mentioned principal monomer.

As above-mentioned principal monomer; For example, can enumerate (methyl) alkyl acrylates such as (methyl) methyl acrylate, (methyl) ethyl propenoate, (methyl) Bing Xisuandingzhi, (methyl) vinylformic acid isopentyl ester, the just own ester of (methyl) vinylformic acid, (methyl) 2-EHA, (methyl) Isooctyl acrylate monomer, (methyl) vinylformic acid ester in the different ninth of the ten Heavenly Stems, (methyl) decyl acrylate, (methyl) dodecylacrylate.

As above-mentioned comonomer, for example, can enumerate vinyl acetate, propionate, vinyl ether, vinylbenzene, vinyl cyanide, methacrylonitrile etc. and contain vinyl compound.

As above-mentioned monomer, for example, can enumerate vinylformic acid, methylacrylic acid, Ba Dousuan, toxilic acid, fumaric acid, methylene-succinic acid etc. and contain carboxylic monomer with functional group; Hydroxyl monomers such as (methyl) vinylformic acid 2-hydroxy methacrylate, (methyl) vinylformic acid 2-hydroxy propyl ester, (methyl) vinylformic acid 4-hydroxyl butyl ester, N hydroxymethyl acrylamide, vinyl carbinol; Tertiary-amino-containing monomers such as (methyl) vinylformic acid dimethylamino ethyl ester, (methyl) vinylformic acid diethylamino ethyl ester, (methyl) vinylformic acid dimethylamino propyl ester; Amide-containing such as acrylic amide, USAF RH-1 monomer; N-methyl (methyl) acrylic amide, N-ethyl (methyl) acrylic amide, N-methoxymethyl (methyl) acrylic amide, N-ethoxyl methyl (methyl) acrylic amide, N tert butyl acrylamide, N-octyl acrylamide etc. contain N substituted amide base monomer; SY-Monomer Gs etc. contain the epoxy group(ing) monomer.

In the aforesaid propylene acids tackiness agent; Can make in the acrylic polymers that forms by such monomer reaction and contain linking agent; Through utilizing this linking agent to make acrylic polymers crosslinked, can improve the insoluble of acrylic adhesives to the gamma-butyrolactone equal solvent.

For example, can suitably contain isocyanates linking agent, epoxy crosslinking agent, aziridines linking agent, chelating class linking agent etc.

As the usage quantity of above-mentioned linking agent, for example, be preferably 0.1～15 mass parts, more preferably 1.0～10 mass parts with respect to aforesaid propylene acids polymkeric substance 100 mass parts.

Such acrylic adhesives obtains suitable bounding force and energy storage Young's modulus easily, therefore we can say the tackiness agent of especially preferably using as the self adhesive tape of this embodiment.

The thickness of binder layer like this is set at about 2～100 μ m usually, is preferably set to about 5～40 μ m.

As above-mentioned back treatment agent, preferably from the field of self adhesive tape, selecting electrolytic solution is used as indissoluble or insoluble back treatment agent for improving from the material known that the separability at self back side uses.

In addition; In the self adhesive tape 1 of this embodiment; Above-mentioned binder layer 20 is the following this point of 4N/15mm width making the sticking operation property of utilizing this self adhesive tape to carry out with respect to the bounding force at self back side is very important aspect good, and it is very important that the tackiness agent through selecting to constitute above-mentioned the binder layer 20 and selection through this back treatment agent etc. is adjusted to above-mentioned bounding force below the 4N/15mm width.

But; Cross when low with respect to the bounding force at self back side; Might damage the function of the range upon range of state that keeps the duplexer that anode foils and Cathode Foil cascade in the electrochemical element, so preferably be adjusted to more than the 1N/15mm width with respect to the bounding force at self back side.

In addition, from the viewpoint of sticking operation property, the stress that preferably when the roll coil of strip is drawn self adhesive tape 1, produces is lower, particularly, preferably regulates the kind or the amount of above-mentioned tackiness agent or above-mentioned back treatment agent, so that low speed uncoiling power is below the 3.5N/15mm width.

Should also can wait with respect to the bounding force (self back side bounding force) at self back side or low speed uncoiling power and regulate through the pattern formation of binder layer, about its concrete numerical value, can according to after in [embodiment] that state method of record measure.

As the back treatment agent that is used to make the such characteristic of self adhesive tape 1 performance, for example, can use as the agent of pendent alkyl groups class back treatment, silicone based back treatment agent and known back treatment agent.

As abovementioned alkyl side group class stripping treatment agent, can enumerate: the stripping treatment agent that is the main body with the multipolymer of the long-chain alkyl derivative of the multipolymer of the multipolymer of the multipolymer of long-chain aliphatic acrylate, perfluoroalkyl acrylate, chain alkyl acrylic amide, toxilic acid, the chain alkyl esterification thing of hydroxyl polymer-containing, the carboxylamine long-chain alkyl groups of hydroxyl polymer-containing, carboxylamine perfluoroalkyl ester of hydroxyl polymer-containing etc.

As above-mentioned silicone based stripping treatment agent, can enumerate the stripping treatment agent of condensed type organic silicon type, add-on type organosilicon type.

In addition, as long as can make the separability of binder layer be increased to prescribed value above (make self back side bounding force be reduced to below the prescribed value), the above-mentioned general polymkeric substance in addition that also can in banding substrate 10, infiltrate is as the back treatment agent.

As such polymkeric substance, can enumerate crystalline polyester resin, modified polypropylene resin etc.

Particularly from gamma-butyrolactone being shown the viewpoint of good insoluble; Be preferably the mixture of any or they in polyvinyl octadecyl carbamate, crystalline polyester resin, the modified polypropylene resin, wherein preferably contain the back treatment agent of polyvinyl octadecyl carbamate.

Such back treatment agent is made coating fluid through using suitable organic solvent, be infiltrated up to this coating fluid in the banding substrate after, remove above-mentioned organic solvent and dry, can be infiltrated up in the banding substrate.

Perhaps, also can under the state of heat fusing, be infiltrated up in the banding substrate.

Above-mentioned back treatment agent is preferred so that constitute the mode that the space part between the fiber (paper pulp) of banding substrate all is full of and infiltrate; But be not must be so that interfibrous space reaches the mode of the state that is full of fully infiltrates, also can residual gapped state infiltrates only around fiber, to adhere to certain degree.

In addition, for example, also can be on thickness direction to the part infiltration back treatment agent of rear side, thereby between zone and binder layer that this back treatment agent is arranged on the banding substrate, in infiltration, generate the zone of the back treatment agent of not infiltrating.

But; Under this situation; Because from the capillary phenomenon of the lateral margin of self adhesive tape, may make electrolytic solution be surrounded on the rear side of binder layer, the area that tackiness agent or back treatment agent are exposed in the electrolytic solution increases; Thereby their meltage is increased, so the back treatment agent preferably is infiltrated up in the banding substrate with the form of at least a portion arrival binder layer.

Reduce, prevent the lax aspect of coiling of duplexer from the adhesive power that suppresses self adhesive tape; Preferred select through the material of tackiness agent, back treatment agent as stated and the form that supports on banding substrate realizes the minimizing of self adhesive tape to the solute of gamma-butyrolactone, preferred so that under the normal temperature (23 ± 2 ℃) in gamma-butyrolactone the not solute of dipping after 24 hours be that mode more than the 60 quality % is selected the material of tackiness agent, back treatment agent and on banding substrate, supported form.

In addition, the amount that is infiltrated up to the above-mentioned back treatment agent in the banding substrate 10 is preferably with every 1m ²Banding substrate is counted 0.01g～10g (dry mass).

The adhesion amount of back treatment agent is preferably 0.01g/m ²More than be because: when being lower than this amount, can't expect stripping result, produce excessive tension force when drawing self adhesive tape, have the possibility that the interlaminar failure of banding substrate perhaps takes place in the band fracture takes place.

In addition, the adhesion amount of back treatment agent is preferably 10g/m ²Below be because: when being set at the adhesion amount above this amount, separability (release property) excessively improves, with self adhesive tape on duplexer, reels 1 enclose the adhesive power that eclipsed partly produces when above maybe be low excessively.

In addition, in these constituent materials, in order to prevent the corrosion of aluminium electrode, the chlorine in the preferred at least banding substrate and the total content of bromine are set at below the 20ppm, and the total content of preferred chlorine and bromine is below the 20ppm with regard to self adhesive tape.

In addition, self adhesive tape preferably forms with the good state of insulativity, is preferably formed the state that has the breakdown voltage more than the 0.1kV for reaching.

But, need not have too high breakdown voltage, it is just enough to have the breakdown voltage that is no more than 3kV usually.

In addition, the self adhesive tape of this embodiment be preferably formed for: in 23 ± 2 ℃ gamma-butyrolactone, measure confining force, constant load is peeled off and during terminal overburden amount, confining force is below the 1mm, constant load is peeled off to below the 50mm, and terminal overburden amount is below the 5mm.

These each characteristics can be measured through the method for record in [embodiment].

In addition; In this embodiment; Owing to use electrolytic solution is shown that insoluble or insoluble material are as the back treatment agent; Do not carry out the existing self adhesive tape of this selection with treatment agent aspect overleaf and compare, can prevent that the coiling of duplexer is lax, can realize that the quality of electrochemical element improves.

Promptly; Even the back treatment agent of not infiltrating, or the back treatment agent of having infiltrated also can be dissolved in the self adhesive tape of electrolytic solution; As time goes on electrolytic solution can be infiltrated up in the banding substrate; Binder layer becomes from rear side (banding substrate one side) and is exposed to the state the electrolytic solution, the adhesive power at the interface of banding substrate and binder layer is reduced, or form the swelling of tackiness agent own or the dissolving of binder layer and adhesive power is reduced.

On the other hand; In the self adhesive tape of this embodiment, adopt to electrolytic solution be insoluble or insoluble material as the back treatment agent, can be with it as the blocking layer; Therefore; Although be exposed in the electrolytic solution at self adhesive tape side edge portions binder layer, this exposed region is minimum, thereby can the influence to adhesive power suppressed lower.

Therefore, for the self adhesive tape of this embodiment,, can reduce the possibility that the characteristic of aluminium electrolutic capacitor changes because of the reduction of adhesive power makes the possibility of the fixedly power reduction of duplexer of reeling low.

Need to prove that among the present invention, the purposes of self adhesive tape is not limited to aluminium electrolutic capacitor, can be used for purposes such as various electrical condensers, electric capacity, battery, can above-mentioned illustrative technology contents suitably be changed under this situation.

For example, in this embodiment, based on the viewpoint that is fit to aluminium electrolutic capacitor the thickness of banding substrate or the kind of intensity, tackiness agent or back treatment agent etc. have been carried out illustration, but these can change according to desired purposes.

Embodiment

Enumerate embodiment below and illustrate in greater detail the present invention, but the invention is not restricted to these embodiment.

(embodiment 1)

As banding substrate, use tensile strength to be 39N/10mm width and tear strength double-deck kraft paper as the 19N/15mm width.

As the back treatment agent, use polyvinyl octadecyl carbamate, from a face side infiltration of banding substrate, making adhesion amount is 0.05g/m ²

On the other hand, at the thickness formation binder layer of another face side, obtain the self adhesive tape of embodiment 1 with 20 μ m.

Need to prove; When forming this binder layer, use the acrylic adhesives that contains the isocyanates linking agent (Japanese polyurethane system, trade(brand)name " Colonate L ") of 2 mass parts with respect to acrylic polymers 100 mass parts that contain 2-EHA 95 mass parts and vinylformic acid 5 mass parts.

(embodiment 2)

Except use tensile strength as 33N/10mm width and tear strength as the individual layer kraft paper of the thickness 25 μ m of 9N/15mm width as the banding substrate, likewise make the self adhesive tape of embodiment 2 with embodiment 1.

(embodiment 3)

Use tensile strength as 33N/10mm width and tear strength as the individual layer kraft paper of the thickness 25 μ m of 18N/15mm width as banding substrate; To the back treatment agent of the rear side of banding substrate infiltration as the mixture (polyvinyl octadecyl carbamate 7 quality %, modified polypropylene resin 93 quality %) of polyvinyl octadecyl carbamate and modified polypropylene resin (Mitsui Chemicals system, trade(brand)name " UNISTOLE H-100 "), making adhesion amount is 9g/m ², the self adhesive tape of making embodiment 3.

Need to prove, about binder layer, identical with embodiment 1,2.

(embodiment 4)

Except use tensile strength as 29N/10mm width and tear strength as the individual layer kraft paper of the thickness 20 μ m of 5N/15mm width as the banding substrate, likewise make the self adhesive tape of embodiment 4 with embodiment 1.

(embodiment 5)

Forming the candy strip on the binder layer, likewise formed self adhesive tape except as shown in Figure 3 with embodiment 1.

Particularly, range upon range of the 20a of tackiness agent of wire that makes the 5mm width that extends along the length direction of banding substrate (20mm width) devices spaced apart and form 2 on width, the self adhesive tape with embodiment 1 is identical in addition.

That is, banding substrate, tackiness agent use banding substrate, the tackiness agent identical with embodiment 1, and the thickness of range upon range of 20a of tackiness agent etc. are also identical with embodiment 1.

Therefore, in the back in the assessment item shown in the paragraph, for the high embodiment of the probability that possibly obtain the result identical implementation evaluation not with embodiment 1.

(comparative example 1)

Except not using the back treatment agent, likewise make the self adhesive tape of comparative example 1 with embodiment 2.

(comparative example 2)

In tackiness agent, do not use the linking agent, likewise make the self adhesive tape of comparative example 2 with embodiment 2.

With these self adhesive tapes is sample, the mensuration shown in enforcement is following.

Need to prove; Self adhesive tape (sample) in below measuring is common with the method for attaching of the plate of SUS304 system; Adopt following method: with #360 sand paper lapped face; Place self adhesive tape with binder layer mode down on the plate of the SUS304 system after cleaning with toluene, the roller that on this self adhesive tape, makes 2kg is with about 5mm/ speed round trip of second.

(MD (length direction) shrinking percentage)

MD direction (length direction) at the big or small sample of 30mm * 30mm is upward drawn standard lines with the interval of about 20mm, and this sample is pasted on the plate of SUS304 system with above-mentioned condition.

Sample dropped into together with the plate of SUS304 system in 280 ℃ the drying machine 30 minutes, after room temperature is placed, through the computes shrinking percentage.

Shrinking percentage (%)=(between the standard lines after 1-drops into 280 ℃ between the standard lines at length/initial stage length) * 100

(solute not ... To gamma-butyrolactone)

The 1g sample flooded 24 hours in 23 ± 2 ℃ gamma-butyrolactone 100cc after, 150 ℃ of dryings 30 minutes, through computes solute not.

Sample mass * 100 at solute (quality %)=dried sample mass/initial stage not

(confining force ... In the gamma-butyrolactone)

The sample that makes width 10mm * length 100mm leans out half the approximately length from the end of the plate of SUS304 system, pastes under these conditions.

For the sample of pasting with the length of about 50mm from the end of the plate of SUS304 system, on the position of the end of test coupon 20mm, with cutter with the orthogonal direction of length direction on cut out the otch that spreads all over whole width.

The weight of 50g is installed in the end of the sample that leans out at the plate from the SUS304 system then.

The plate face of this SUS plate is kept vertical, make above-mentioned weight become vertical sagging state, impregnated in 23 ± 2 ℃ the gamma-butyrolactone to make the part that above-mentioned otch the is set undersurface mode of submerging at least.

Under this state, kept 7 hours, behind the gamma-butyrolactone of the plate of the useless cloth wiping SUS system of usefulness and the remained on surface of sample, measure the expansion length (deflected length) of the otch that is provided with on the sample with reading lens.

(constant load is peeled off ... In the gamma-butyrolactone)

The sample of width 10mm * length 150mm is temporarily sticked on the plate of SUS304 system under these conditions.

Then, with sample from length direction one distolateral to peel off up to pasting length be 100mm, at the weight of above-mentioned one distolateral installation 10g of the sample of peeling off.With this sample paste face under mode make the plate maintenance level of SUS304 system; Make the part of being stripped from sagging with the right angle with respect to the plate of SUS304 system; Sample was all flooded 3 hours in 23 ± 2 ℃ gamma-butyrolactone, measure the length that sample is further peeled off with the steel ruler.

(end is peeled off ... In the gamma-butyrolactone)

At an end of the length direction of the sample of 2.5mm width * 100mm the weight of 50g is installed, another distolateral brazen metal bar (pole) at diameter 2mm is gone up 2 circles of reeling.

Make the metal bar that is wound with this sample remain in horizontal direction being equipped with under the state of weight, and make metal bar keep the state that can pivot, dipping is 24 hours in 23 ± 2 ℃ gamma-butyrolactone, the length of peeling off during dipping with steel ruler mensuration.

(end is peeled off ... After the reflow soldering)

Make the metal bar that is wound with this sample remain in horizontal direction being equipped with under the state of weight; And make metal bar keep the state that can pivot; It is imported in the reflow soldering furnace; The above-mentioned reflow soldering furnace that turns round reaches 260 ℃ after making the interior temperature of stove when the heating beginning, play 300 seconds, then naturally cooling.

Then, with the strip length of self adhesive tape in the steel ruler determination test.

(tensile strength)

To be that the band sample of the width 10mm that cuts out of MD direction is arranged on the tensile testing machine that grip separation is set at 100mm with the length direction; Stress (N) when when implementing tension test in order to 300mm/ minute speed fracture taking place is obtained tensile strength divided by specimen width (10mm width).Test conditions is 23 ± 2 ℃, 50 ± 5%RH.

(tear strength)

On the band sample that with the length direction is the width 15mm that cuts out of MD direction; The position inboard from a lateral margin to 5mm cuts out otch (breach); It is arranged on makes the roughly mid-way of this cutting part on the tensile testing machine in anchor clamps; Stress (N) when likewise using fracture with " tensile strength " is obtained tear strength divided by specimen width (15mm width).Test conditions is 23 ± 2 ℃, 50 ± 5%RH.

(meltage of back treatment agent, tackiness agent)

Back treatment agent, the tackiness agent of 1g were at room temperature flooded in the gamma-butyrolactone of 100g 24 hours respectively, measure the quality change before and after the dipping, with reduction as meltage.

(modular ratio of tackiness agent)

Use the energy storage Young's modulus of determination of viscoelasticity machine under measuring 30 ℃～250 ℃ (G '), the value of the energy storage Young's modulus under 30 ℃ is made as " 1 ", obtain the ratio of the energy storage Young's modulus under 250 ℃, as " modular ratio ".

Need to prove that mensuration is to fitting, make sample that total thickness reaches the thickness more than the 2mm between the binder layer, the gained material being become discoideus with the punch press stamping-out of diameter 7.9mm and sample that obtain carries out.

More specifically, with parallel plate (the TA Instruments corporate system of this sample (diameter 7.9mm, thickness are the discoideus sample of 2mm) with the diameter 8mm of stainless steel; Model: 708.0157) clamp, use visco-elasticity spectrograph (Rheometric Scientific corporate system; Goods name " ARES "); Under the condition of jaw pressure: 100g weight, frequency: 1Hz, apply shear-stress; Simultaneously 30 ℃～250 ℃ temperature province with 5 ℃/minute heat-up rate and under shear mode mensuration visco-elasticity, obtain energy storage Young's modulus (G ').

(breakdown voltage)

Use the dielectric breakdown test machine, sample is inserted in the electrode of diameter 6mm, will in air, the rate of rise of per second be set at 500V/ second (interchange), the magnitude of voltage when measuring generation puncture of insulation (cut-off current 25mA) is as breakdown voltage.Test conditions is 23 ± 2 ℃, 50 ± 5%RH.

(cl content)

The 0.5g that materialses extracted 1 hour at 120 ℃ with pure water 50g, and gains are measured through ion chromatography.

(bromine content)

According to BS EN14582 (2007)/pyrolysated TP, measure through ion chromatography.

(sticking operation property)

The form that the self adhesive tape of embodiment, comparative example directly is bonded in the back side of banding substrate with binder layer is processed the roll coil of strip of width 2.5mm, coiling length 100m, confirms the walking states of self adhesive tape when drawing with 50m/ minute speed.

Need to prove, at this moment, will be from beginning to walk the total length of 100m, the sample that the sample that self adhesive tape ruptures is judged to be " zero ", fracture will take place is judged to be " * ".

(self back side bounding force)

The sample of the about 120mm of width 15mm * length is pasted on the SUS304 of the about 125mm of the about 50mm * length of width under aforementioned condition (using roller, speed 5mm/ second, the round trip of 2kg); On the material of gained, further paste the sample (the about 120mm of width 15mm * length) of the about 120mm of another width 15mm * length under the same conditions and make it overlapping; 23 ± 2 ℃ environment held after 30 ± 10 minutes; With the sample of upside from distolateral peeling off to midway; This sample end of peeling off is arranged on the chuck of tensile testing machine; And the SUS plate is arranged on another chuck, implements the stripping test that peel angle is 180 degree, measure self back side bounding force with 300mm/ minute draw speed.

Need to prove that the arithmetical av in the time of will in the interval of 80mm, implementing above-mentioned stripping test is as self back side bounding force.

(low speed uncoiling power)

The roll coil of strip of width 15mm is arranged at the state that can rotate freely on the chuck of tensile testing machine, and the end of the self adhesive tape that will draw from this roll coil of strip is arranged on another chuck, peels off with 300mm/ minute draw speed, has measured uncoiling power.

These are measured the result and are shown in following table 1.

[table 1]

In the table, " ND " expression " does not detect (not detected) ".

In addition, "-" expression is estimated.

Also can find out by this result,, can prevent to be contained in duplexer lax of the inside of electrochemical element, can access the good self adhesive tape of operation property according to the present invention.

Claims

1. self adhesive tape, the electrochemical element that it is used for possessing in the housing duplexer that the insulation paper that electrolytic solution arranged across infiltration cascades anode foils and Cathode Foil uses through being bonded in the position that joins with said electrolytic solution, it is characterized in that,

A face side at banding substrate possesses binder layer, and said binder layer is below the 4N/15mm with respect to the bounding force at self back side, and the percent thermal shrinkage under 280 ℃ is below 2% in the longitudinal direction.

2. self adhesive tape as claimed in claim 1, wherein, the not solute of dipping in the time of 24 hours is 60～100 quality % in 23 ± 2 ℃ gamma-butyrolactone.

3. self adhesive tape as claimed in claim 1, wherein, said binder layer is the tackiness agent formation below the 50 quality % by the meltage of dipping in the time of 24 hours in 23 ± 2 ℃ gamma-butyrolactone.

4. self adhesive tape as claimed in claim 1, wherein, the tackiness agent that constitutes said binder layer is 0.8～1.5 in the ratio of the energy storage Young's modulus of the energy storage Young's modulus under 250 ℃ under with respect to 30 ℃.

5. self adhesive tape as claimed in claim 1; Wherein, At said binder layer, be formed with the non-laminated section of tackiness agent that the range upon range of portion of tackiness agent that forms through the range upon range of said tackiness agent of a said face side at banding substrate and not range upon range of said tackiness agent make said banding substrate exposing surface.