KR20190124250A - Pressure-sensitive adhesive composition, pressure-sensitive adhesive and laminate - Google Patents

Abstract

The adhesive composition for bonding the convex part surface of base material sheet [I] which has convex part surface of surface roughness Ra0.1-100 micrometers, and the flat surface of base material sheet [II] which has flat surface, is glass transition temperature in this invention. It is related with the polyester adhesive composition containing polyester-based resin (A) which is 0 degrees C or less.

Description

Pressure-sensitive adhesive composition, pressure-sensitive adhesive and laminate

This invention is an adhesive composition for bonding together the convex part surface of base material sheet [I] which has convex part, and the flat surface of base material sheet [II] which has flat surface, especially the adhesive composition for bonding prism sheets, and prism It relates to at least one of the adhesive compositions for bonding a sheet and a diffusion sheet.

Moreover, this invention relates to the adhesive using the said adhesive composition, and the laminated body using the said adhesive.

Conventionally, in order to bond a prism sheet etc., an ultraviolet curable adhesive, a thermosetting adhesive, etc. are used as an adhesive agent. For example, Patent Document 1 describes "Three Bond 3042B" as a specific example of an ultraviolet curable adhesive, and "Sanke Epocua and Epoch Co., Ltd. are mixed at 5: 1 as a specific example of a thermosetting adhesive." One ”.

Patent document 1 JP 2007-155938 A

However, in the technique described in Patent Literature 1, when bonding the prism sheet to some extent, the adhesiveness is obtained to some extent, but it is still not satisfactory, and according to the advancement of the recent technology, the adhesiveness or the adhesiveness is further demanded.

In the case of using an ultraviolet curable adhesive or a thermosetting adhesive, ultraviolet irradiation or heat treatment is required to develop adhesive force, but in this case, the ultraviolet irradiation effect becomes uneven due to diffuse reflection by a prism sheet, or the expansion and contraction of the sheet due to heat treatment. Thereby, peeling may occur as the contact moves. Therefore, the adhesive which can be used for bonding a prism sheet is required, without requiring ultraviolet irradiation or heat processing.

Accordingly, the present invention requires ultraviolet irradiation or heat treatment with excellent adhesiveness for bonding the convex portion of the base sheet [I] having the convex portion and the flat surface of the base sheet [II] having the flat surface under such a background. It is an object of the present invention to provide a pressure-sensitive adhesive composition capable of expressing adhesive strength.

Moreover, an object of this invention is to provide the adhesive using the said adhesive composition, and the laminated body using the said adhesive.

By the way, as a result of earnestly examining in order to solve the said subject, the present inventors discovered that the adhesive which has the adhesive composition containing polyester-type resin expresses very outstanding adhesiveness.

Especially, when using the adhesive which has an adhesive composition containing polyester-type resin whose glass transition temperature is 0 degrees C or less, even if it is an adhesive layer of the thin film which does not bury an uneven surface with an adhesive, when sticking an uneven surface and a flat surface, It discovered that the outstanding adhesiveness was expressed and completed this invention.

That is, this invention relates to the following <1>-<9>.

In the adhesive composition for bonding the convex part of base material sheet [I] which has convex part surface of <1> surface roughness Ra0.1-100 micrometers, and the flat surface of base material sheet [II] which has flat surface, glass transition temperature The adhesive composition containing polyester-based resin (A) which is 0 degrees C or less.

<2> The structural component of the said polyester-based resin (A) contains a polyhydric carboxylic acid component (a1) and a polyol component (a2), and the content rate of the sum total of the aromatic polyhydric carboxylic acid component and aromatic polyol component in the said structural component The adhesive composition as described in <1> which is 40 mol% or less with respect to the sum total of this polyhydric carboxylic acid component (a1) and the said polyol component (a2).

The adhesive composition as described in <1> or <2> which further contains a <3> crosslinking agent (B).

The adhesive composition as described in <3> whose <4> said crosslinking agent (B) is an isocyanate type crosslinking agent.

The pressure-sensitive adhesive in which the complexing composition according to any one of <5> <1> to <4> is crosslinked with a crosslinking agent (B).

The laminated body by which the base material sheet [I] which has convex part surface of <6> surface roughness Ra0.1-100 micrometers, and the base material sheet [II] which has flat surface are laminated | stacked through the adhesive as described in <5>.

The laminated body as described in <6> whose <7> said base sheet [I] and the said base sheet [II] are a prism sheet or a diffusion sheet, respectively.

The laminated body as described in <6> or <7> whose thickness of a <8> adhesive layer is 10 micrometers or less.

<9> The convex part surface of base material sheet [I] which has convex part surface of surface roughness Ra0.1-100 micrometers, and flat surface of the adhesive composition containing polyester-based resin (A) whose glass transition temperature is 0 degrees C or less. Use for bonding together the flat surface of base material sheet [II] to have.

The adhesive composition and adhesive of this invention are for bonding the convex part of base material sheet [I] which has convex part surface of surface roughness Ra0.1-100 micrometers, and the flat surface of base material sheet [II] which has flat surface, and is adhesive It is very excellent in that it does not require ultraviolet irradiation or heat treatment and can develop adhesive force.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view showing a very suitable embodiment of the laminate of the present invention.
It is a schematic exploded perspective view explaining the laminated body shown in FIG.
3 is a cross-sectional view of the prism sheet 2 and the prism sheet 3 taken along the line X-X 'in the schematic exploded perspective view shown in FIG.
FIG. 4 is a cross-sectional view similar to FIG. 3 except that a plurality of prisms 8 having a high unevenness level are arranged in the prism pattern 22 at regular intervals in the prism sheet 2 of the cross-sectional view of FIG. 3.
FIG. 5: is sectional drawing which showed the bonding of the diffusion sheet 1 and the prism sheet 2 of the laminated body shown in FIG. 1 in more detail.
FIG. 6: is sectional drawing which cut | disconnected the diffusion sheet 1 and the prism sheet 2 along X-X 'from the schematic exploded perspective view shown in FIG. 2 (equivalent to the exploded view of FIG. 5).

Next, embodiment of this invention is described in detail. However, this invention is not limited to this embodiment.

<Adhesive Composition>

The adhesive composition of this invention is an adhesive composition for bonding the convex part of base material sheet [I] which has convex part surface of surface roughness Ra0.1-100 micrometers, and the flat surface of base material sheet [II] which has flat surface, A glass transition temperature contains polyester resin (A) which is 0 degrees C or less.

Here, the structural component of an adhesive composition is demonstrated.

[Polyester Resin (A)]

The polyester resin (A) is characterized by having a glass transition temperature of 0 ° C. or less, and such glass transition temperature is preferably -70 to 0 ° C, particularly preferably -60 to -10 ° C, more preferably Is -30 to -15 占 폚.

When such glass transition temperature exceeds an upper limit, an adhesion layer becomes hard and the adhesiveness of the adhesive composition of this invention falls. On the contrary, even when glass transition temperature is too low, the cohesion force of an adhesion layer falls and the adhesiveness of the adhesive composition of this invention falls.

As the polyester resin (A) to be contained in the pressure-sensitive adhesive composition, it is usually selected to increase the cohesive force of the pressure-sensitive adhesive layer, make it difficult to deform with respect to the load from the outside, and increase the adhesive force, and the glass transition temperature is higher than 0 ° C. do. However, in order to bond a prism sheet, in order to prevent the unevenness | corrugation of a prism sheet from being filled in an adhesive layer, it is calculated | required to make an adhesive layer into a thin film especially 10 micrometers or less especially than usual. In that case, higher flexibility and tackiness must be provided, and the glass transition temperature of the polyester-based resin (A) contained in the adhesive composition needs to be 0 degrees C or less.

Here, the glass transition temperature (Tg) of the said polyester resin is a value measured using the differential scanning calorimeter DSCQ20 by TA Instruments.

In addition, the measurement temperature ranges from -90 degreeC to 100 degreeC, and a temperature increase rate is 10 degreeC / min.

Polyester-based resin (A), Preferably, the copolymerization component containing a polyhydric carboxylic acid component (a1) and a polyol component (a2) is made into a structural component. Polyester-based resin (A), Preferably, it is obtained by copolymerizing the said copolymerization component.

[Polyhydric carboxylic acid component (a1)]

As a polyhydric carboxylic acid component (a1) used by this invention, For example, aromatic dicarboxylic acid, such as terephthalic acid, isophthalic acid, benzyl maronic acid, diphenic acid, 4,4'- oxydibenzoic acid, naphthalenedicarboxylic acid; Maronic acid, dimethylmaronic acid, succinic acid, glutaric acid, adipic acid, trimethyl adipic acid, pimeric acid, 2,2-dimethylglutamic acid, azaline acid, sebacic acid, fumaric acid, maleic acid, itaconic acid, thiodipropionic acid, diglycol Aliphatic dicarboxylic acids such as acids;

1,3-cyclopentanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 2,5-norbornanedicarboxylic acid, And divalent carboxylic acids such as alicyclic dicarboxylic acids such as adamantanedicarboxylic acid; and the like.

These may be used alone or in combination of two or more.

Among these, it is preferable that the said copolymerization component contains a small amount of aromatic dicarboxylic acid from a viewpoint of providing moderate cohesion force to an adhesive layer, and it is especially preferable to contain isophthalic acid.

As content rate of such aromatic dicarboxylic acid, it is preferable that it is 50 mol% or less with respect to the whole polyhydric carboxylic acid component (a1), Especially preferably, it is 1-30 mol%, More preferably, it is 2-20 mol%. . When such content rate is too high, the glass transition temperature of polyester-based resin (A) becomes high and there exists a tendency for the adhesive composition of this invention to be unable to acquire sufficient adhesive performance. When such content rate is too low, the glass transition temperature of polyester-based resin (A) will become low, and cohesion force will become low and it exists in the tendency for the adhesive composition of this invention to acquire sufficient adhesive performance.

Moreover, it is preferable that the said copolymerization component contains aliphatic dicarboxylic acid from a viewpoint of providing a feeling of tackiness, It is preferable to contain aliphatic dicarboxylic acid of 4-12 carbon atoms especially, and it is preferable to contain sebacic acid. desirable.

As content rate of such aliphatic dicarboxylic acid, it is preferable that it is 40 mol% or more with respect to the whole polyhydric carboxylic acid component (a1), Especially preferably, it is 50 mol%-99 mol%, More preferably, it is 70-98 mol %to be. When such content rate is too low, the glass transition temperature of polyester-based resin (A) becomes high and there exists a tendency for the adhesive composition of this invention to be unable to acquire sufficient adhesive force. When such content rate is too high, cohesion force will become low too much and there exists a tendency for the adhesive force of the adhesive composition of this invention to fall.

In this invention, it is preferable to use together aromatic dicarboxylic acid and aliphatic dicarboxylic acid as polyhydric carboxylic acid component (a1) from a viewpoint of the balance of adhesive physical property, and as content ratio (molar ratio), aromatic dicarboxylic acid / aliphatic dicarboxylic acid It is preferable that it is = 1/99-49/51, Especially preferably, aromatic dicarboxylic acid / aliphatic dicarboxylic acid = 2/98-30/70, More preferably, aromatic dicarboxylic acid / aliphatic dicarboxylic acid = 3 / 97-20 / 80.

In addition, for the purpose of increasing the branching point in the polyester-based resin (A), trivalent or higher polyhydric carboxylic acid may be used, and as such trivalent or higher carboxylic acid, for example, trimellitic acid, pyromellitic acid, adamantane Tan tricarboxylic acid, trimesic acid, etc. are mentioned. Among these, it is preferable to use trimellitic acid from a viewpoint which gelation does not occur comparatively relatively.

As a content rate of such trivalent or more polyhydric carboxylic acid, it is 10 mol% or less, Especially preferably 0.1-5 mol% with respect to the whole polyhydric carboxylic acid component (a1) from a viewpoint which can raise the cohesion force of an adhesive. When there is too much content, it exists in the tendency for gelatinization to arise at the time of manufacture of polyester-based resin (A).

[Polyol Component (a2)]

As a polyol component (a2) used by this invention, for example, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1, 3- propanediol, 2, 4- dimethyl- 2-ethyl Hexane-1,3-diol, 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol (neopentyl glycol), 2-ethyl-2-butyl-1,3-propane Diol, 2-ethyl-2-isobutyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1, Aliphatic diols such as 5-pentanediol and 2,2,4-trimethyl-1,6-hexanediol;

1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, spiroglycol, tricyclodecane dimethanol, adamantanediol, 2,2,4,4-tetra Alicyclic diols such as methyl-1,3-cyclobutanediol;

4,4'- thiodiphenol, 4,4'- methylene diphenol, 4,4'- dihydroxy biphenyl, o-, m- and p- dihydroxy benzene, 2, 5- naphthalenediol, p -Aromatic diols such as xylenediol and ethylene oxide and propylene oxide adducts thereof;

And dihydric alcohols.

These may be used alone or in combination of two or more.

Among these, aliphatic diols and alicyclic diols are preferable from the viewpoint of excellent reactivity, and particularly preferably, as aliphatic diols, ethylene glycol, diethylene glycol, 1 3-propanediol, 2-methyl-1,3-propanediol, Neopentyl glycol, 1, 4- butanediol, 1, 5- pentanediol, 1, 6- hexanediol, and as cycloaliphatic diol, 1, 2- cyclohexane dimethanol, 1, 3- cyclohexane dimethanol, 1, 4 -Cyclohexane dimethanol.

As such content ratio of aliphatic diol, it is preferable that it is 99 mol% or less with respect to the whole polyol component (a2), Especially preferably, it is 3-97 mol%, More preferably, it is 5-95 mol%. When such content rate is too low, the glass transition temperature of polyester-resin (A) will become high, adhesiveness will fall and adhesive strength will fall, and when such content rate is too high, glass of polyester-based resin (A) will be The transition temperature is lowered, the cohesive force is lowered, and the adhesive strength tends to be lowered.

As such content ratio of alicyclic diol, it is preferable that it is 1 mol% or more with respect to the whole polyol component (a2), Especially preferably, it is 3 mol%-97 mol%, More preferably, it is 5-95 mol%. When such a content ratio is too low, toughness will become low and adhesive strength will fall, and when such a content ratio is too high, the solubility to a solvent will become low and it will become difficult to process.

In this invention, it is preferable to use an aliphatic diol and an alicyclic diol together as a polyol component (a2) from a viewpoint of the balance of adhesive physical property, and as a content ratio (molar ratio), aliphatic diol / alicyclic diol = 45 / 55-1 / 99 It is preferable that they are aliphatic diol / alicyclic diol = 30 / 70-3 / 97, More preferably, aliphatic diol / alicyclic diol = 15 / 85-5 / 95.

Moreover, in addition to the aromatic diol mentioned above from the viewpoint of providing a moderate cohesion force to an adhesive layer, a small amount of aromatic polyols, such as bisphenol S and bisphenol A, may be contained.

Moreover, a trihydric or more polyhydric alcohol can also be used for the purpose of extending a branching point in polyester resin (A), As a trihydric or more polyhydric alcohol, it is pentaerythritol, dipentaerythritol, and tripentaeryth, for example. Ritol, glycerin, trimethylol propane, trimethylol ethane, 1,3,6-hexane triol, adamantane triol, etc. are mentioned.

As a content rate of such a trivalent or more polyhydric alcohol, Preferably it is 10 mol% or less, Especially preferably, it is 0.1-5 mol% with respect to the whole polyol component (a2), and when there are too many such content rates, it is polyester type There exists a tendency for manufacture of resin (A) to become difficult.

As a compounding ratio of a polyhydric carboxylic acid component (a1) and a polyol component (a2), it is preferable that the polyol component (a2) is 1.0-2.0 equivalent per 1.0 equivalent of polyhydric carboxylic acid component (a1), Especially preferably, it is 1.1- 1.7 equivalents. When the content ratio of the polyol component (a2) is too low, the acid value tends to be high and high molecular weight is difficult, and when such content ratio is too high, the yield tends to be lowered.

As a structural component of polyester-based resin (A), although it selects arbitrarily from said polyhydric carboxylic acid component (a1) and a polyol component (a2), it is aromatic with respect to the sum total of a polyhydric carboxylic acid component (a1) and a polyol component (a2). It is preferable that adhesiveness becomes high that the content rate of the sum total of a polyhydric carboxylic acid component and an aromatic polyol component is 40 mol% or less. 1-25 mol% is preferable and, as for the said content rate, 2-20 mol% is especially preferable. When the said content rate is higher than 40 mol%, there exists a tendency for the adhesive force of the adhesive composition of this invention to fall, and even if the said content rate is too low, there exists a tendency for the adhesive force of the adhesive composition of this invention to fall.

The polyester-based resin (A) is preferably prepared by arbitrarily selecting the polyhydric carboxylic acid component (a1) and the polyol component (a2) and subjecting them to a polycondensation reaction by a known method in the presence of a catalyst.

In such a polycondensation reaction, an esterification reaction is carried out first, followed by a condensation reaction.

In such esterification reaction, a catalyst is used, and specifically, titanium-based catalysts, such as tetra isopropyl titanate and tetrabutyl titanate, antimony-based catalysts, such as antimony trioxide, germanium-based catalysts, such as germanium dioxide, Catalysts such as zinc acetate, manganese acetate, dibutyltin oxide, and the like, and one or two or more of these may be used. Among these, antimony trioxide, tetrabutyl titanate, and germanium dioxide are preferable from the balance of the height and the color of the catalytic activity.

It is preferable that the compounding quantity of the said catalyst is 1-10,000 ppm with respect to an electropolymerization component, Especially preferably, it is 10-5,000 ppm, More preferably, it is 20-3,000 ppm. If the amount of such a compounding is too small, the polymerization reaction tends to be difficult to proceed sufficiently, and even if the amount of such a compounding is too large, there is no advantage such as a shortening of the reaction time and a tendency for side reactions to occur easily.

About reaction temperature at the time of esterification reaction, 160-260 degreeC is preferable, Especially preferably, it is 180-250 degreeC, More preferably, it is 200-250 degreeC. If the reaction temperature is too low, the reaction tends to be difficult to proceed sufficiently. If the reaction temperature is too high, side reactions such as decomposition tend to occur. In addition, the pressure at the time of reaction may be normal pressure normally.

After the esterification reaction, a condensation reaction is performed.

As reaction conditions for the condensation reaction, a catalyst similar to that used in the above esterification reaction is further doubled in the same degree, and the reaction temperature is preferably 220 to 280 ° C (particularly preferably 230 to 270 ° C). It is preferable to gradually depressurize and finally react at 5 hPa or less.

If the reaction temperature is too low, the reaction tends to be difficult to proceed sufficiently. If the reaction temperature is too high, side reactions such as decomposition tend to occur.

It is preferable that the number average molecular weight of polyester-type resin (A) is 5,000 or more, Especially preferably, it is 10,000-100,000, More preferably, it is 15,000-80,000.

When such a number average molecular weight is too small, sufficient cohesion force may not be obtained as an adhesive, heat resistance and mechanical strength tend to fall, and when the number average molecular weight is made too large, flexibility will become inferior and initial adhesiveness tends to fall.

In addition, said number average molecular weight is a number average molecular weight by conversion of a standard polystyrene molecular weight, and it is a column liquid: TSKgel SuperMultipore HZ-M (exclusion limit molecular weight: 2) in high-performance liquid chromatography (The Tosoh Corporation make, "HLC-8320 GPC"). × 10 ⁶ , theoretical number of stages: 16,000 stages / piece, filler material: styrene-divinylbenzene copolymer, filler particle size: 4 μm), it is measured by using two series.

The acid value of the polyester resin (A) is preferably 5 mgKOH / g or less, particularly preferably 1 mgKOH / g or less, more preferably 0.5 mgKOH / g or less, particularly preferably 0.2 mgKOH / g or less. If the acid value is too high, the pressure-sensitive adhesive will invade the adherend or the reaction with the crosslinking agent will be inhibited, and the adhesive force tends to be insufficient.

In addition, the acid value of the said polyester-type resin (A) is calculated | required by neutralization titration based on JISK070.

Polyester-based resin (A) has a glass transition temperature of 0 degrees C or less, Although it does not specifically limit as a method of making glass transition temperature into 0 degrees C or less, Although it polymerizes by increasing the ratio of the monomer with few functional groups, and the functional group number A monomer having a low rigidity that does not have an aromatic ring or the like by adjusting the amount of the trifunctional or higher monomer to reduce the branching of the polyester-based resin (A), or to reduce the crosslinking structure generated by using a monomer having a small number of unsaturated groups. There exists a method of polymerizing by increasing the ratio of, and it can be said that glass transition temperature is 0 degrees C or less combining these.

[Crosslinking agent (B)]

Although the adhesive composition of this invention contains the said polyester-type resin (A), it is preferable to contain a crosslinking agent (B) further.

It is because aggregation becomes strong by crosslinking polyester-based resin (A) using a crosslinking agent (B), and the performance as an adhesive can be exhibited more effectively.

As such a crosslinking agent (B), the crosslinking agent which has a functional group which reacts with the hydroxyl group and / or carboxyl group contained in polyester-based resin (A), such as an isocyanate type crosslinking agent and an epoxy type crosslinking agent, is mentioned, for example. Among them, the isocyanate-based crosslinking agent is particularly preferable from the viewpoint of achieving a good balance of initial adhesiveness, mechanical strength and heat resistance.

As such an isocyanate type crosslinking agent, for example, tetramethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, xylene diisocyanate, hydrogenated xylene di Polyisocyanates, such as isocyanate, are mentioned, and isocyanate addition products, such as the tolylene diisocyanate addition product of trimethylol propane, the hexamethylene diisocyanate addition product, and the isophorone diisocyanate addition product, etc. are mentioned. Moreover, the said isocyanate type crosslinking agent can be used even if the isocyanate part blocked with phenol, lactam, etc .. These crosslinking agents can be used individually by 1 type, and can mix and use 2 or more types.

Although the compounding quantity of such a crosslinking agent (B) can be suitably selected according to the molecular weight of a polyester-type resin (A), and a use purpose, Usually, 1-10 parts are preferable with respect to 100 parts of polyester-based resin (A) by weight conversion. Moreover, 1-5 parts are preferable and 1-3 parts are especially preferable. If the blending amount of such a crosslinking agent (B) is less than 1 part, the adhesive force tends to be lowered due to insufficient hardness of the pressure-sensitive adhesive layer, and the adhesive force tends to be lowered even when it is more than 10 parts.

〔etc〕

In the pressure-sensitive adhesive composition of the present invention, in addition to the above components, antistatic agents, hydrolysis inhibitors, other acrylic adhesives, other adhesives, urethane resins, rosin, rosin esters, hydrogenated rosin esters, and phenols within a range that does not impair the effects of the present invention. Tackifiers such as resins, aromatic modified terpene resins, aliphatic petroleum resins, alicyclic petroleum resins, styrene resins and xylene resins, plasticizers such as polyols, antioxidants, labeling agents, rheology control agents, colorants, fillers, Conventionally well-known additives, such as an anti-aging agent, a ultraviolet absorber, and a functional pigment | dye, and the compound which causes coloring or discoloration by ultraviolet-ray or radiation irradiation can be mix | blended, It is preferable that the compounding quantity of these additives is 30 weight% or less of the whole adhesive composition, Especially preferably, it is 20 weight% or less.

Moreover, when the adhesive composition of this invention contains a hydrolysis inhibitor with polyester resin (A), the improvement of durability under high temperature, high humidity can be expected.

As said hydrolysis inhibitor, it does not specifically limit, A conventionally well-known thing can be used, For example, the compound which reacts and couple | bonds with the carboxylic acid terminal group of polyester-based resin (A) is mentioned, Specifically, And compounds having functional groups such as carbodiimide groups, epoxy groups, and oxazoline groups.

Among these, a carbodiimide group containing compound is preferable from a viewpoint of the high effect of losing the catalytic activity of the proton derived from a carboxyl terminal group.

As said carbodiimide group containing compound, although the well-known carbodiimide or polycarbodiimide which has one or more carbodiimide groups (-N = C = N-) in a molecule | numerator may be used normally, under high temperature, high humidity, It is preferable that it is a compound containing 2 or more carbodiimide groups in a molecule | numerator from a viewpoint of durability, and especially it is a compound containing 3 or more, 5 or more, especially 7 or more. Moreover, when 50 or more carbodiimide groups are contained in a molecule | numerator, since molecular structure becomes large too much, it exists in the tendency which is not preferable.

Moreover, as said carbodiimide group containing compound, it is preferable to use a thing with many weight average molecular weights from a hydrolysis resistance viewpoint. It is preferable that the weight average molecular weight of a carbodiimide group containing compound is 500 or more, It is more preferable that it is 2,000 or more, It is more preferable that it is 3,000 or more. In addition, the upper limit of a weight average molecular weight is 50,000 normally. When the weight average molecular weight of a carbodiimide group containing compound is too small, there exists a tendency for hydrolysis resistance to fall. Moreover, when the weight average molecular weight of a carbodiimide group containing compound is too big | large, there exists a tendency for compatibility with polyester resin to fall.

Moreover, it is also preferable to use the high molecular weight polycarbodiimide produced | generated by decarbonation condensation reaction of diisocyanate in presence of a carbodiimidation catalyst.

As such high molecular weight polycarbodiimide, the thing which carried out decarbonation condensation reaction of the following diisocyanate is mentioned.

As such diisocyanate, for example, 4,4'- diphenylmethane diisocyanate, 3,3'- dimethoxy-4,4'- diphenylmethane diisocyanate, 3,3'- dimethyl-4, 4 VIII-diphenylmethane diisocyanate, 4,4'- diphenyl ether diisocyanate, 3,3'- dimethyl-4,4'- diphenyl ether diisocyanate, 2, 4- tolylene diisocyanate, 2, 6- tolyl Rendiisocyanate, 1-methoxyphenyl-2,4-diisocyanate, isophorone diisocyanate, 4,4'- dicyclohexyl methane diisocyanate, tetramethyl xylene diisocyanate, etc. are mentioned, These are single or two types. The above can be used together. Such high molecular weight polycarbodiimide can also be synthesize | combined and can use a commercial item.

It is preferable that it is 0.01-10 weight part with respect to 100 weight part of polyester resins (A), It is more preferable that it is 0.1-5 weight part, It is still more preferable that content of the said hydrolysis inhibitor is 0.2-3 weight part. When there is too much such content, there exists a tendency for turbidity to arise by incompatibility with polyester-based resin (A), and when too small, there exists a tendency for sufficient durability to be difficult to be obtained.

Moreover, as for content of the said hydrolysis inhibitor, it is preferable to optimize content according to the acid value of polyester-type resin (A), and it is an adhesive composition with respect to the total number-of-moles (a) of the acidic functional group of a polyester-type resin (A). It is preferable that molar ratio ((b) / (a)) of the sum total (b) of functional group moles of hydrolysis inhibitor in it is 0.5 <= (b) / (a), and 1 <= (b) / (a) <= 1, It is more preferable that it is 000, and it is more preferable that 1.5 <= (b) / (a) <= 100. If the molar ratio ((b) / (a)) of (b) to (a) is too low, there exists a tendency for damp-heat performance to fall. Moreover, when the molar ratio ((b) / (a)) of (b) to (a) is too high, there exists a tendency for compatibility with polyester-based resin (A) to fall, or adhesive force, cohesion force, and durability capability fall.

In addition, the pressure-sensitive adhesive composition of the present invention, in addition to the additives, may be a small amount of impurities and the like contained in the raw material for the production of the components of the pressure-sensitive adhesive composition.

The adhesive composition of this invention can be obtained by stirring and mixing the above-mentioned structural component in accordance with a well-known method.

The viscosity at 25 degrees C of the adhesive composition of this invention is 1-100,000 mPa * s normally from a viewpoint of the coating property in a base material, Preferably it is 10-50,000 mPa * s, Especially preferably, it is 50-30,000 mPa * s. . If the viscosity is too low, unevenness tends to occur during coating on the substrate, and if the viscosity is too high, coating on the substrate tends to be difficult.

Moreover, although the adhesive composition of this invention can contain a solvent and can also be used as a solvent-free composition, it is preferable to use it as a solvent-free composition which can abbreviate | omit the process of drying the solvent in an adhesive. In addition, the density | concentration in the case of containing a solvent is 3 to 90 weight% normally based on the solid content weight of an adhesive, Preferably it is 5 to 80 weight%, Especially preferably, it is 10 to 70 weight%. If the concentration is too low, the labeling property tends to be lowered when the substrate is coated, and if the concentration is too high, the viscosity tends to increase, making it difficult to coat.

As such a solvent, For example, alcohols, such as methanol, ethanol, a propanol, n-butanol, i-butanol, ketones, such as acetone, methyl isobutyl ketone, methyl ethyl ketone, cyclohexanone, an ethyl cellosolve, etc. Cellosolves, aromatics such as toluene, xylene, glycol ethers such as propylene glycol monomethyl ether, acetates such as methyl acetate, ethyl acetate and butyl acetate, diacetone alcohols, and the like. It may be used independently and may use 2 or more types together.

<Adhesive>

The pressure-sensitive adhesive of the present invention is crosslinked by the cross-linking agent (B) of the pressure-sensitive adhesive composition of the present invention.

That is, the pressure-sensitive adhesive composition of the present invention preferably crosslinks the polyester-based resin (A) with a crosslinking agent (B), functions as an adhesive, and can be suitably used as an adhesive for sticking base sheets together. .

It is preferable that the adhesive of this invention does not contain an acidic group substantially, Specifically, it is preferable that acid value is 10 mgKOH / g or less, Especially preferably, it is 1 mgKOH / g or less, More preferably, it is 0.1 mgKOH / g or less .

In addition, the acid value of the said adhesive can be calculated | required by the method similar to the acid value of the said polyester-type resin (A).

<Laminated body>

In the laminated body of this invention, base sheet [I] and base sheet [II] are laminated | stacked through the adhesive of this invention.

The laminated body of this invention obtained by laminating | stacking base sheet [I] and base sheet [II] using the adhesive of this invention is a laminated body excellent in time-lapse stability with few peelings of an adhesive layer, etc.

As said base material sheet [I], the at least single side | surface of a sheet | seat has a convex part surface of surface roughness Ra0.1-100 micrometers, A convex part surface is equipped with some convex part, and a convex part height may be constant or can differ. Moreover, a convex part shape can mention a dot, stripe, a grating | lattice, etc., for example, It is especially preferable that it is stripe form both in an optical property and an adhesive.

And as base material sheet [I], it is especially preferable that it is a lens sheet in which convex lenses formed in the uniaxial direction were adjacent, and was arranged substantially on the entire surface, a so-called prism sheet, and a diffusion sheet with irregularities formed at random. As a prism sheet, the prism sheet of 60 micrometers of pitch, the average of uneven | corrugated height, 30 micrometers, and the vertex angle of a convex part of 90 degrees (right angle) etc. are mentioned, for example.

In addition, the measurement of the said surface roughness Ra (micrometer) is based on JIS B 0601 (1982) and center line average roughness, and in the case of a prism sheet and a diffusion sheet, the average of uneven | corrugated height corresponds to this.

The well-known various forms can be employ | adopted for the material of this base material sheet [I], and a manufacturing method. For example, a concave transfer roller (the inverted form of the convex surface is formed on the surface) which rotates the sheet-shaped resin material extruded from the die at a speed approximately equal to the extrusion speed of this resin material, and this transfer roller The manufacturing method of the resin sheet which opposes and is pinched by the nip roller board which arrange | positions and rotates at the same speed and transfers the uneven | corrugated shape of the transfer roller surface to a resin material is employable.

Moreover, the manufacturing method of the resin sheet which laminates | transforms the transfer die plate (stamper) and the resin plate in which the inverted form of the convex part surface is formed in the surface by hot press, and press-forms by thermal transfer can be employ | adopted.

As a resin material used by such a manufacturing method, a thermoplastic resin can be used, for example, polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyester, polyolefin, acrylic resin, polystyrene, polycarbonate , Polyamide, PET (polyethylene terephthalate), polyester resin such as biaxially stretched polyethylene terephthalate, polyethylene naphthalate, polyamideimide, polyimide, aromatic polyamide, cellulose acylate, cellulose tri acetate, cellulose Although acetate propionate, a cellulose diacetate, etc. are mentioned, Acrylic resin is preferable from a viewpoint of an optical characteristic and reaction rate.

Moreover, as another manufacturing method, manufacture of the resin sheet which transfer-forms the unevenness | corrugation of the surface of an uneven | corrugated roller (the inversion type of the convex part surface is formed in the surface) on the surface of a transparent film (for example, the film which consists of said thermoplastic resin) Method may be employed.

On the other hand, as said base sheet [II], if at least single side | surface of a sheet has a flat surface, the other surface may have a convex part shape shown to the said base sheet [I]. Here, a flat surface means the plane without unevenness, Preferably surface roughness Ra means less than 0.1 micrometer. The lower limit of surface roughness Ra is 0.001 micrometer normally.

As such base material sheet [II], for example, polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyester, polyolefin, acrylic, polystyrene, polycarbonate, polyamide, PET (polyethylene tere) Phthalate), PEN (polyethylene naphthalate), polyester-based resin, polymethyl methacrylate, polyether ether ketone, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, biaxially stretched polyethylene terephthalate, polyamideimide A well-known transparent film of materials, such as a polyimide, an aromatic polyamide, a cellulose acylate, a cellulose triacetate, a cellulose acetate propionate, a cellulose diacetate, can be used.

Among them, polyolefins such as acrylic resins such as polyester resins such as polyethylene terephthalate and polyethylene naphthalate, cellulose acylate and polymethyl methacrylate, polycarbonate, polypropylene and cyclic polyolefin can be preferably used. Among these, polyester resin is preferable from an optical characteristic and a workability viewpoint.

Moreover, as base material sheet [II], the sheet single side | surface is the convex part surface shown by the said base material sheet [I], and the sheet whose other surface is a flat surface can also be used. In particular, in order to obtain an optical sheet, it is preferable that base sheet [II] is a prism sheet or a diffusion sheet.

And in order to obtain the more outstanding optical sheet, both base sheet [I] and base sheet [II] are prism sheets, base sheet [I] is a diffusion sheet, base sheet [II] is a prism sheet, and base sheet It is preferable that [I] is a prism sheet, and base material sheet [II] is a diffusion sheet.

The adhesive composition of this invention can exhibit the very outstanding adhesive force in the adhesion of prism sheets which were difficult to obtain sufficient adhesive force conventionally, and the adhesion of a prism sheet and a diffusion sheet.

When base sheet [I] and base sheet [II] are a prism sheet together, both are arrange | positioned in the direction which the axis | shaft of a convex lens (prism) is substantially orthogonal. That is, when the axis | shaft of the convex lens of the prism sheet of base material sheet [I] is arrange | positioned in the vertical direction, the axis | shaft of the convex lens of the prism sheet of base material sheet [II] is arrange | positioned in parallel direction.

Sectional drawing of one very suitable embodiment of the laminated body of this invention is shown in FIG. The laminated body shown in FIG. 1 is a hardening body of the diffusion sheet 1, the hardened body 5 of an adhesive composition, the prism sheet 2, the hardened body 5 of an adhesive composition, the prism sheet 3, and the adhesive composition in order from the bottom. (5), It is an optical sheet in which the diffusion sheet 4 is laminated | stacked. The form in which the base sheet [I] and the base sheet [II] are a prism sheet together is illustrated between the prism sheet 2 and the prism sheet 3, and also the base sheet [I] is a prism sheet, a base sheet [ II] is a diffusion sheet illustrated between the prism sheet 3 and the diffusion sheet 4, and the form in which the base sheet [I] is a diffusion sheet and the base sheet [II] is a prism sheet is a diffusion sheet ( It is illustrated between 1) and the prism sheet 2. In addition, the figure shown in more detail about the bonding of the diffusion sheet 1 and the prism sheet 2 is shown in FIG.

Moreover, the schematic exploded perspective view explaining the laminated body shown in FIG. 1 is shown in FIG. 2 (The hardened body 5 is not shown), and the prism sheet 2 and the prism sheet 3 are shown in FIG. 3 is a cross-sectional view taken along the line.

Here, the diffusion sheet 1, the diffusion sheet 4, the prism sheet 2, and the prism sheet 3 are formed by using a recess transfer roller, a transfer template (stamper), an uneven roller, or the like in the resin material as described above. It can manufacture by attaching unevenness | corrugation.

In addition, the diffusion sheet 1 and the diffusion sheet 4 may be formed of, for example, acrylic beads containing a plurality of beads having light diffusivity on a surface (single side) of a transparent film (support) such as a PET film, a polycarbonate film, or a polystyrene. It can also be produced by fixing with a binder such as a resin, an epoxy resin, a urethane resin, or an olefin resin, and has a predetermined light diffusion performance. The diffusion sheet 1 and the diffusion sheet 4 mainly have luminance in the backlight surface. Used to reduce stains.

As said beads, acrylic beads, silica beads, barium sulfate, titanium oxide, calcium silicate, etc. are mentioned, for example. For example, TDF-127 (made by Toray Saehan), Opars BS-080 (made by Keiwa Corporation), D141 (made by Tsujiden Corporation), etc. are mentioned.

Moreover, it is preferable that the average particle diameter of a beads is 100 micrometers or less, It is especially preferable that it is 50 micrometers or less, It is more preferable that it is 25 micrometers or less. In addition, it is preferable that the diffusion sheet 1 and the diffusion sheet 4 have different average particle diameters of the beads, and the light diffusion performance also differs.

Moreover, as said prism sheet 2 and prism sheet 3, the prism pattern 22 of an array form is formed on the surface of the base material 21 and base material 31, such as PET film, a polycarbonate film, and polystyrene, for example. ) And the prism pattern 32, which are mainly used for the purpose of condensing the light of the backlight to improve luminance.

As a material of the prism pattern 22 and the prism pattern 32, although an acryl-type photopolymer, a polycarbonate, fluorene resin, etc. are used, it is not limited to this. In addition, the prism pattern 22 and the prism pattern 32 may not be strictly a prism shape, but may have an R-shape in the top portion, or may be in the form of a wave film or a downward prism.

As for the laminated body of FIG. 1, the prism sheet 2 and the prism sheet 3 adhere | attach with the hardened | cured material 5 of the adhesive composition of this invention. Specifically, a thin film of an adhesive composition is applied to the flat surface of one prism sheet 3, and the prism sheet 3 is applied to the prism pattern surface (convex portion) of the other prism sheet 2 using the adhesive composition. It combines and adheres by hardening the said adhesive composition. At this time, the prism sheet 2 and the prism sheet 3 are point-bonded or pre-bonded by the convex part of the prism sheet 2.

Moreover, the diffusion sheet 1 and the prism sheet 2 of FIG. 1 may be stuck by the hardened | cured material 5 of the adhesive composition of this invention. Specifically, a thin film of the pressure-sensitive adhesive composition is applied to the flat surface of one prism sheet 2, the prism sheet 2 is bonded to the convex portion of the diffusion sheet 1 using the pressure-sensitive adhesive composition, and the pressure-sensitive adhesive composition It can also stick by hardening (FIG. 5).

FIG. 3 is a cross-sectional view taken along the line X-X 'shown in FIG. 2 of the prism sheet 2 and the prism sheet 3 in the schematic exploded perspective view of FIG. 2. As shown in the cross-sectional view of FIG. 3, the prism pattern 22 of the prism sheet 2 and the prism pattern 32 of the prism sheet 3 may each be composed of a plurality of convex portions (prisms) having the same uneven height. . In addition, the prism pattern 22 of the prism sheet 2 and the prism pattern 32 of the prism sheet 3 may be the prism pattern of the same uneven | corrugated height, respectively, and may differ.

As another embodiment, as shown in the prism sheet 2 of FIG. 4, a prism for arranging a plurality of convex portions (prism) 8 once higher than the prism pattern 22 having the same uneven height at regular intervals in the prism pattern 22. Sometimes sheets are used.

As shown in FIG. 4, when the some convex part (prism) 8 once higher than the prism pattern 22 is arrange | positioned at a fixed space | interval, only the high convex part (prism) 8 adhere | attaches. Among the plurality of convex portions, the intervals at which the high convex portions (prism 8) are provided are from 1/3 (one of three convex portions to high convex portions) to 1/10 (ten convex portions) from the viewpoint of improving luminance. Is set to a high convex portion).

FIG. 6: is sectional drawing which cut | disconnected the diffusion sheet 1 and the prism sheet 2 in the schematic exploded perspective view of FIG. 2 along X-X 'shown in FIG. 6 corresponds to an exploded view of FIG. 5 showing the combination of the diffusion sheet 1 and the prism sheet 2 in detail. As shown in the cross-sectional view of FIG. 6, the prism pattern 22 of the prism sheet 2 is arranged in a regular pattern, and the diffusion layer 9 of the diffusion sheet 1 is arranged in a random pattern. In addition, the prism pattern 22 and the prism pattern 32 may be uniform in height and shape or may be nonuniform. In addition, the shape of the diffusion layer 9 may be random or regular.

[Method for Manufacturing Laminate]

As a manufacturing method of the laminated body of this invention, the process of laminating | stacking base material sheet [I] and base material sheet [II] using the said adhesive composition is provided, and the process of hardening the said adhesive composition is provided.

Specifically, after uniformly applying the pressure-sensitive adhesive composition in the form of a liquid to the flat surface of the base sheet [II], it is bonded to the convex portion of the base sheet [I] through the pressure-sensitive adhesive composition and pressed to perform aging treatment. By performing, an adhesive composition hardens | cures and a laminated body can be obtained.

When coating such an adhesive composition on the flat surface of base material sheet [II], for example, a reverse coater, a gravure coater (direct, reverse, offset), a bar reverse coater, a roll coater, a die coater, a bar coater, a rod coater Or the like can be applied by dipping.

For example, a roll laminator or the like can be used for such bonding and crimping, and the pressure is selected from the range of 0.1 to 10 MPa.

Such an aging treatment should just be what can be set as the adhesive layer which hardens an adhesive composition by crosslinking reaction, etc., and has moderate cohesion force. Although the conditions of an aging process are not specifically limited, Preferably it is 15-60 degreeC, More preferably, it is 30-50 degreeC, Preferably it is 1 day or more, More preferably, it is 1-10 days, More preferably, it is 2 It is preferable to perform an aging process for -8 days.

It is preferable that it is 10 micrometers or less, and, as for the thickness of the adhesive layer in the laminated body of this invention obtained by the above, it is more preferable that it is 0.01-10 micrometers. If the thickness is too thin, there is a tendency that the cohesive force of the adhesive layer itself cannot be obtained and the adhesive strength cannot be obtained. If the thickness is too thick, the adhesive tends to stick to the recesses of the prism, and the performance as a prism tends to decrease. have. The adhesive composition of this invention can express favorable adhesiveness even in the adhesive layer of such a thin film.

The adhesive composition of this invention becomes an adhesive excellent in the adhesive force in the initial stage and time-lapse, and is used for bonding together the convex part surface of the base material sheet [I] which has convex part, and the flat surface of base material sheet [II] which has flat surface. Although it is used, among these, it is especially suitable for bonding of prism sheets (illustration shown in FIG. 3), bonding of a prism sheet and a diffusion sheet (illustrated in FIG. 6), and it is favorable without being dependent on the moisture content of prism sheet itself. It shows adhesiveness.

(Example)

Hereinafter, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited to a following example, unless the summary is exceeded. In addition, "part" and "%" mean a basis of weight in an Example.

Prior to the Example and the comparative example, each component of the adhesive composition shown below and the base material sheet were prepared.

[Synthesis example of polyester-based resin (A-1)]

9.6 parts of isophthalic acid and 46.8 parts of sebacic acid as polyhydric carboxylic acid component (a1) and 27.1 parts of neopentyl glycol as polyol component (a2) in a reaction can equipped with a thermometer, a stirrer, a rectifying column, a nitrogen inlet tube and a vacuum device. , 4-butanediol 13.0 parts, 1,6-hexanediol 3.0 parts, trimetholpropane 0.5 part, 0.01 part of tetrabutyl titanate were added as a catalyst, the temperature was gradually raised to 250 degreeC of internal temperature, and esterification was performed over 4 hours. . Thereafter, the mixture was heated up to an internal temperature of 260 ° C, 0.01 part of tetrabutyl titanate was added as a catalyst, and the resultant was subjected to a polycondensation reaction over a period of 3 hours under reduced pressure to 1.33 hPa to give a polyester resin (A-1) (glass transition temperature of -50 ° C, Number average molecular weight 21,000, and aromatic component ratio 10 mol%) were obtained.

In addition, the glass transition temperature was measured by the method described below. In addition, said "aromatic component ratio" is aromatic polyhydric carboxylic acid component and aromatic polyol component with respect to the sum total of a polyhydric carboxylic acid component (a1) and the said polyol component (a2) in the structural component of polyester-based resin (A). It means content ratio (mol%) of the sum total.

[Production of Adhesive Composition (1)]

To 100 parts (50 parts of solid content) of the said polyester resin (A-1) solution, 3 parts of isocyanate type crosslinking agents (Nippon Polyurethanes make, "Colonate L55E", solid content ratio 55%) as a crosslinking agent (B), And 1 part of hydrolysis inhibitors (Nisshinbo Chemical Co., Ltd. product, "carbodilite V-07", solid content ratio 50%), and it stirred, and obtained the adhesive composition (1).

[Synthesis example of polyester-based resin (A-2), manufacture of adhesive composition (2)]

Ethylene glycol as a polyhydric carboxylic acid component (a1) 9.6 parts of isophthalic acid, 23.3 parts of sebacic acid, 21.7 parts of azaline acid, and a polyol component (a2) in a reaction can equipped with a thermometer, a stirrer, a rectifying column, a nitrogen inlet tube and a vacuum device. 1.8 parts, 43.6 parts of 1, 4- cyclohexane dimethanols, 0.02 part of germanium dioxide were put as a catalyst, the temperature was raised gradually to internal temperature 250 degreeC, and esterification was performed over 4 hours. Then, it raises to internal temperature 270 degreeC, depressurizes to 1.33 hPa, and performs polycondensation reaction over 3 hours, and polyester-based resin (A-2) (glass transition temperature -25 degreeC, number average molecular weight 27,000, aromatic component ratio 10 mol) %) Was obtained. As mentioned above, the crosslinking agent (B) and the hydrolysis inhibitor were added, and the adhesive composition (2) was obtained.

[Synthesis example of polyester-based resin (A-3), manufacture of adhesive composition (3)]

In a reaction can equipped with a thermometer, a stirrer, a rectifying column, a nitrogen inlet tube and a vacuum device, 19.0 parts of terephthalic acid, 19.0 parts of isophthalic acid, and 18.0 parts of sebacic acid, and polyol component (a2) as polyhydric carboxylic acid component (a1). 4.0 parts, 12.0 parts of diethylene glycol, 28.0 parts of neopentyl glycol and 0.02 parts of germanium dioxide were put as a catalyst, the temperature was gradually raised to 250 degreeC of internal temperature, and esterification was performed over 4 hours. Then, it raises to internal temperature 270 degreeC, depressurizes to 1.33 hPa, and performs polycondensation reaction over 3 hours, and it is polyester-based resin (A-3) (glass transition temperature of 4 degreeC, number average molecular weight 16,000, aromatic component ratio 36 mol%). ) The crosslinking agent (B) was added as mentioned above and the adhesive composition (3) was obtained.

[Synthesis example of polyester-based resin (A-4), manufacture of adhesive composition (4)]

Ethylene glycol as a polyhydric carboxylic acid component (a1), 21.0 parts of terephthalic acid, 16.6 parts of isophthalic acid, 23.0 parts of adipic acid, and a polyol component (a2) in a reaction can equipped with a thermometer, a stirrer, a rectifying column, a nitrogen inlet tube, and a vacuum device. 18.4 parts, 21.0 parts of neopentyl glycol and 0.02 parts of germanium dioxide were put as a catalyst, the temperature was gradually raised to 250 degreeC of internal temperature, and esterification was performed over 4 hours. Then, it raises to internal temperature 270 degreeC, depressurizes to 1.33 hPa, and performs polycondensation reaction over 3 hours, and it is polyester-based resin (A-4) (glass transition temperature 11 degreeC, number average molecular weight 25,000, aromatic component ratio 30 mol%). ) The crosslinking agent (B) was added as mentioned above and the adhesive composition (4) was obtained.

[Synthesis example of acrylic resin (A'-5), manufacture of adhesive composition (5)]

The water bus-on was heated to reflux at 90 ° C while refluxing, adding 310 g of ethyl acetate and 0.19 g of azobis isobutyronitrile (AIBN) as a solvent, into a flask with a rounded two-liter bottom mouth. 459.5 g of butyl acrylate (BA) in the glass bottle of 1 L of volumes beforehand. 40 g of acrylic acid (AAc) and 0.5 g of 2-hydroxyethyl methacrylate (HEMA) were mixed, and this mixed monomer was added dropwise to the flask over 2 hours. One hour after completion of the dropwise addition, AIBN0.40g and 70 g of toluene were added and reacted again for 2 hours to obtain an acrylic resin (AV-5) solution. The glass transition temperature of acrylic resin (A'-5) was -28 degreeC, the weight average molecular weight was 87.70,000, and dispersion degree was 4.9.

The crosslinking agent (B) was added as mentioned above and the adhesive composition (5) was obtained.

<Measurement of Glass Transition Temperature>

10 mg was put into an aluminum pan with respect to said polyester resin and acrylic resin, and it heated up from 25 degreeC to 100 degreeC at 10 degreeC / min using a differential scanning calorimeter (DSCQ20 by TA Instruments), After holding at 100 ° C for 10 minutes, the mixture was cooled to -90 ° C at 10 ° C / min and held at -90 ° C for 15 minutes. The extension line of two baselines is drawn on the DSC curve when it heated up to 100 degreeC at 10 degree-C / min again, and the straight line which equidistates in the longitudinal axis direction between two extension lines is drawn, and the temperature of the intersection of the straight line and a DSC curve is obtained. The transition temperature was taken.

EXAMPLE 1

A prism sheet (SUNTECHOPT Corp. SPX3 surface roughness 7-8 micrometers) was used as a base material sheet [I], and a biaxially stretched PET film (EMBLETS, the flat surface manufactured by UNICHIKA Co., Ltd.) of 38 micrometers thickness was used as base material sheet [II]. Prepared.

The above pressure-sensitive adhesive composition (1) is coated onto the base sheet [II] using an applicator so that the thickness of the pressure-sensitive adhesive layer is 10 μm, and the coated surface and the prism sheet surface of the base sheet [I] are subjected to a 2 kg hand roller. Bonded. Thereafter, the pressure-sensitive adhesive composition layer was crosslinked to form an pressure-sensitive adhesive layer by performing an aging treatment at 40 ° C. for 7 days to obtain a laminate in which base sheet [I] and base sheet [II] were laminated through an adhesive.

EXAMPLE 2 AND COMPARATIVE EXAMPLES 1-3

In the said Example 1, each laminated body was obtained like Example 1 except having used the adhesive composition shown in following Table 1 instead of the adhesive composition (1).

The performance evaluation was performed as follows using each laminated body obtained above, and the result was combined with Table 1 and shown.

[Peel strength evaluation]

Each laminated body obtained above was cut to 15 cm x 2.5 cm, and 180 degree peeling strength (N / 25mm) was measured according to the measuring method of the adhesive force of JI SZ 0237 at room temperature of 23 degreeC.

From the result of the said Table 1, the laminated body of Examples 1 and 2 is a lamination of the comparative examples 1 and 2 which coated the adhesive composition using the polyester-type resin with both 180 degree peeling strength high and glass transition temperature higher than 0 degreeC. Although the sieve and glass transition temperature are 0 degrees C or less, it turned out that all have the outstanding adhesiveness compared with the laminated body of the comparative example 3 which coated the adhesive composition using acrylic resin.

Although this invention was detailed also demonstrated with reference to the specific embodiment, it is clear for those skilled in the art that various changes and correction can be added without deviating from the mind and range of this invention. This application is based on the JP Patent application (patent application 2017-059469) of an application on March 24, 2017, The content is taken in here as a reference.

Since the adhesive composition of this invention is excellent in adhesiveness in bonding of the convex part surface of the base material sheet [I] which has convex part, and the flat surface of the base material sheet [II] which has flat surface, it is excellent in adhesiveness, besides the adhesive use for prism sheets For example, it can also be used for bonding various optical films or sheets, bonding electronic components, precision instruments, packaging materials, display materials, etc.

One; Diffusion sheet, 2; Prism sheet, 3; Prism Sheet,
4; Diffusion sheet, 5; Hard object of the pressure-sensitive adhesive composition
8; High convex (prism) 11; Substrate 12; Diffusion Layer,
21; Substrate 22; Prism pattern, 31; materials,
32; Prism pattern, 41; Substrate, 42; Diffusion layer.

Claims (9)

In the adhesive composition for bonding the convex part of base material sheet [I] which has convex part surface of surface roughness Ra0.1-100 micrometers, and the flat surface of base material sheet [II] which has flat surface, glass transition temperature is 0 degreeC. The adhesive composition containing the following polyester-type resin (A). The method according to claim 1,
The constituent component of the said polyester-based resin (A) contains a polyhydric carboxylic acid component (a1) and a polyol component (a2), and the content rate of the sum total of the aromatic polyhydric carboxylic acid component and aromatic polyol component in the said structural component is said polyvalent The adhesive composition which is 40 mol% or less with respect to the sum total of a carboxylic acid component (a1) and the said polyol component (a2). The method according to claim 1 or 2,
The adhesive composition further containing a crosslinking agent (B). The method according to claim 3,
The adhesive composition in which the said crosslinking agent (B) is an isocyanate type crosslinking agent. The adhesive which any one of Claims 1-4 is bridge | crosslinked by the crosslinking agent (B). The laminated body by which the base material sheet [I] which has convex part surface of surface roughness Ra0.1-100 micrometers, and the base material sheet [II] which has flat surface are laminated | stacked through the adhesive of Claim 5. The method according to claim 6,
The laminated body whose said base sheet [I] and the said base sheet [II] are a prism sheet or a diffusion sheet, respectively. The method according to claim 6 or 7,
The laminated body whose thickness of an adhesive layer is 10 micrometers or less. The base sheet which has a convex part surface of the base material sheet [I] which has convex part surface of surface roughness Ra0.1-100 micrometers, and the flat surface of the adhesive composition containing polyester-based resin (A) whose glass transition temperature is 0 degrees C or less. The usage method for bonding the flat surface of [II].

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