TWI795522B - Adhesive sheet, method for manufacturing same, and method for manufacturing image display device - Google Patents

Abstract

本發明係關於一種光硬化性黏著片，該黏著片(5)係含有基礎聚合物以及光硬化性化合物之黏著劑組合物以層狀形成。黏著片(5)之霧度為1%以下，對於玻璃之接著力為1.5 N/10 mm以下，溫度25℃下之剪切儲存彈性模數為0.15 MPa以下。黏著片(5)係藉由硬化使聚合率為99%時之玻璃轉移溫度為-3℃以下，並且溫度25℃下之剪切儲存彈性模數為0.16 MPa以上。The present invention relates to a photocurable adhesive sheet. The adhesive sheet (5) is formed in a layered form of an adhesive composition containing a base polymer and a photocurable compound. The adhesive sheet (5) has a haze of 1% or less, an adhesive force to glass of 1.5 N/10 mm or less, and a shear storage elastic modulus of 0.15 MPa or less at a temperature of 25°C. The adhesive sheet (5) is hardened so that the glass transition temperature at a polymerization rate of 99% is -3°C or lower, and the shear storage elastic modulus at a temperature of 25°C is 0.16 MPa or higher.

Description

黏著片及其製造方法、以及圖像顯示裝置之製造方法Adhesive sheet, method for manufacturing same, and method for manufacturing image display device

本發明係關於一種具有光硬化性之黏著片及其製造方法。進而，本發明係關於一種使用該黏著片之圖像顯示裝置之製造方法。The invention relates to a light-curable adhesive sheet and a manufacturing method thereof. Furthermore, the present invention relates to a method of manufacturing an image display device using the adhesive sheet.

作為行動電話、智能行動電話、汽車導航裝置、個人電腦用顯示器、電視機等各種圖像顯示裝置，廣泛使用液晶顯示裝置或有機EL顯示裝置。以防止由來自外表面之衝擊而造成之圖像顯示面板之破損等為目的，有時於圖像顯示面板之視認側設置透明樹脂板、或玻璃板等前面透明板(亦稱為「覆蓋窗口」等)。另外，近年來，於圖像顯示面板之視認側具備觸控面板之設備正在普及。Liquid crystal display devices and organic EL display devices are widely used as various image display devices such as mobile phones, smart mobile phones, car navigation devices, monitors for personal computers, and televisions. For the purpose of preventing damage to the image display panel caused by the impact from the outer surface, a front transparent plate such as a transparent resin plate or a glass plate (also called a "cover window") is sometimes provided on the viewing side of the image display panel. "wait). In addition, in recent years, devices equipped with a touch panel on the viewing side of an image display panel have become popular.

作為於圖像顯示面板之前面配置前面透明板、或觸控面板等前面透明構件之方法，提出經由黏著片將圖像顯示面板與前面透明構件貼合之「層間填充結構」。有時於觸控面板與前面透明板之間亦設置黏著片。於層間填充結構中，構件間之空隙被黏著劑填充，因此，界面之折射率差減小，能夠抑制由反射、或散射引起之視認性之降低。另外，於層間填充結構中，利用黏著片將構件間貼合而進行固定，故而，與前面透明構件僅被固定於殼體之情況相比，具有不容易發生由落下等衝擊引起之前面透明構件之剝離之優點。As a method of arranging a front transparent plate or a front transparent member such as a touch panel on the front surface of an image display panel, an "interlayer filling structure" in which the image display panel and the front transparent member are bonded via an adhesive sheet is proposed. Sometimes an adhesive sheet is also provided between the touch panel and the front transparent plate. In the interlayer filling structure, the gap between the members is filled with the adhesive, so the difference in refractive index at the interface is reduced, and the decrease in visibility due to reflection or scattering can be suppressed. In addition, in the interlayer filling structure, the adhesive sheet is used to bond and fix the members. Therefore, compared with the case where the front transparent member is only fixed to the case, it is less likely to cause the front transparent member to be damaged by impact such as dropping. The advantages of stripping.

於前面透明構件之邊緣，以裝飾或遮光為目的，有時形成著色層(裝飾印刷層)。若於具有裝飾印刷層之透明構件上貼合黏著劑，則容易於印刷階差部之周邊產生氣泡。藉由使用厚度較大之黏著片而具有階差吸收性，能夠抑制氣泡混入等不良情況。另外，藉由使用厚度較大之黏著片，有耐衝擊性提高之傾向。A colored layer (decorative printing layer) is sometimes formed on the edge of the front transparent member for the purpose of decoration or light shielding. If the adhesive is pasted on the transparent member with the decorative printing layer, air bubbles are likely to be generated around the printed step portion. By using a thicker adhesive sheet, it has step absorbency, and it is possible to suppress defects such as air bubbles. In addition, impact resistance tends to be improved by using a thick adhesive sheet.

由於能夠以均勻之厚度形成厚度較大之黏著片，於層間填充用黏著片中廣泛使用無溶劑型光硬化型黏著劑(例如參照專利文獻1以及專利文獻2)。於使用光硬化型黏著劑之情形時，亦可將黏著劑組合物之一部分為未硬化之狀態(半硬化)之黏著片與被接著體貼合，然後進行光硬化。於該方法中，半硬化黏著片之流動性較高，故而，貼合時之階差吸收性較高，藉由其後之光硬化而能夠提高接著保持力。 [先前技術文獻] [專利文獻]Since a thick adhesive sheet can be formed with a uniform thickness, a solventless light-curable adhesive is widely used in an adhesive sheet for interlayer filling (for example, refer to Patent Document 1 and Patent Document 2). In the case of using a photocurable adhesive, an adhesive sheet in which a part of the adhesive composition is in an uncured state (semi-cured) can be bonded to an adherend, followed by photocuring. In this method, since the fluidity of the semi-cured adhesive sheet is high, the step absorption at the time of lamination is high, and the adhesive holding force can be improved by subsequent photocuring. [Prior Art Literature] [Patent Document]

[專利文獻1]日本專利特開2014-125524號公報 [專利文獻2]國際公開第2013/161666號[Patent Document 1] Japanese Patent Laid-Open No. 2014-125524 [Patent Document 2] International Publication No. 2013/161666

[發明所欲解決之問題][Problem to be solved by the invention]

先前，覆蓋窗口等前面透明構件之尺寸大於顯示面板，於較顯示面板之外周緣更靠外側之區域中，前面透明構件與殼體利用接著帶等貼合。即，前面透明構件藉由併用向殼體之貼合及利用層間填充用黏著片進行之向顯示面板表面之貼合而被固定。Previously, the size of the front transparent member such as the cover window was larger than that of the display panel, and the front transparent member and the casing were bonded together with an adhesive tape or the like in an area outside the outer periphery of the display panel. That is, the front transparent member is fixed by bonding to the case and bonding to the surface of the display panel using an adhesive sheet for interlayer filling in combination.

近年來，以智能行動電話等移動設備為中心，顯示裝置之窄框緣化、或無邊框化正在推進。伴隨窄框緣化、或無邊框化，顯示面板10之尺寸與前面透明構件7之尺寸同等或者大於前面透明構件7之尺寸。於此種構成中，無法利用接著帶等將殼體9與前面透明構件7固定，必須僅利用層間填充用黏著片5來固定前面透明構件7(參照圖2)。隨之，對層間填充用黏著片要求更高之接著力，並且要求於較寬之溫度範圍內不會發生由落下等衝擊引起之剝離。In recent years, centering on mobile devices such as smart phones, display devices have been narrowed or bezel-less. With narrower frame or no frame, the size of the display panel 10 is equal to or larger than the size of the front transparent member 7 . In such a configuration, the case 9 and the front transparent member 7 cannot be fixed with an adhesive tape or the like, and the front transparent member 7 must be fixed only with the adhesive sheet 5 for interlayer filling (see FIG. 2 ). Accordingly, higher adhesive force is required for interlayer filling adhesive sheets, and it is required that no peeling due to impact such as dropping occurs in a wide temperature range.

另外，於顯示面板之尺寸與前面透明構件之尺寸同等或者大於前面透明構件7之尺寸之情形時，為了填補殼體9與前面透明構件7之間隙90，有時利用樹脂材料進行密封。例如，使熔融狀態之樹脂材料流入至間隙90，然後冷卻至室溫而使樹脂固化，藉此利用樹脂材料進行密封。若使高溫之樹脂流入至間隙90，則於間隙90之附近，前面透明構件7、殼體9以及黏著片5達到高溫，於樹脂固化時被冷卻。對於黏著片5要求對於變形應力之接著耐久性以使即便於伴隨著此種溫度變化，前面透明構件以及殼體等中發生尺寸變形之情形時亦不發生被接著體間之剝離。In addition, when the size of the display panel is the same as that of the front transparent member or larger than that of the front transparent member 7, a resin material may be used for sealing to fill the gap 90 between the case 9 and the front transparent member 7. For example, a resin material in a molten state is poured into the gap 90, and then cooled to room temperature to solidify the resin, thereby performing sealing with the resin material. When high-temperature resin flows into the gap 90, the front transparent member 7, the case 9, and the adhesive sheet 5 reach a high temperature in the vicinity of the gap 90, and are cooled when the resin solidifies. Adhesive durability against deformation stress is required for the adhesive sheet 5 so that peeling between adherends does not occur even when dimensional deformation occurs in the front transparent member, case, etc. accompanying such a temperature change.

專利文獻1等中揭示之先前之層間填充用黏著片之玻璃轉移溫度較高，因此，低溫下之接著性、或耐衝擊性較差。另一方面，專利文獻2中揭示之低玻璃溫度之黏著片對於變形應力之接著耐久性較低，難以兼具低溫下之耐衝擊性及對於樹脂密封等之加熱・冷卻時之變形應力之耐久性。The conventional adhesive sheet for interlayer filling disclosed in Patent Document 1 and the like has a high glass transition temperature, and therefore has poor adhesion at low temperatures or impact resistance. On the other hand, the low glass temperature adhesive sheet disclosed in Patent Document 2 has low adhesion durability against deformation stress, and it is difficult to combine impact resistance at low temperature and durability against deformation stress during heating and cooling of resin sealing, etc. sex.

鑒於上述情況，本發明之目的在於提供一種具有階差吸收性、並且於較寬之溫度範圍內之耐衝擊性以及對於變形應力之接著耐久性優異之黏著片。 [解決問題之技術手段]In view of the above circumstances, an object of the present invention is to provide an adhesive sheet that has step absorption and is excellent in impact resistance over a wide temperature range and adhesion durability against deformation stress. [Technical means to solve the problem]

本發明係關於一種將含有基礎聚合物之黏著劑以片狀形成之黏著片。黏著片之霧度為1%以下。The present invention relates to an adhesive sheet in which an adhesive containing a base polymer is formed into a sheet. The haze of the adhesive sheet is 1% or less.

於一實施形態中，黏著片為將含有基礎聚合物以及光硬化性化合物之黏著劑組合物以層狀形成之光硬化性黏著片。光硬化性黏著片之對於玻璃之接著力為1.5 N/10 mm以上，並且溫度25℃下之剪切儲存彈性模數為0.15 MPa以下。In one embodiment, the adhesive sheet is a photocurable adhesive sheet formed in layers of an adhesive composition containing a base polymer and a photocurable compound. The adhesive force of the photocurable adhesive sheet to glass is 1.5 N/10 mm or more, and the shear storage elastic modulus at a temperature of 25°C is 0.15 MPa or less.

光硬化性黏著劑組合物較佳為所謂之半硬化之狀態，並且聚合率為90%～98%。半硬化黏著片之玻璃轉移溫度較佳為-5℃以下。半硬化黏著片之損失正切之峰頂值較佳為1.6以上。The photocurable adhesive composition is preferably in a so-called semi-hardened state, and the polymerization rate is 90% to 98%. The glass transition temperature of the semi-hardened adhesive sheet is preferably below -5°C. The peak value of the loss tangent of the semi-hardened adhesive sheet is preferably 1.6 or more.

本發明之黏著片之一實施形態為黏著劑組合物之聚合率為99%左右或其以上。此種完全硬化之黏著片例如可藉由上述半硬化黏著片之光硬化而獲得。亦可藉由聚合率未達90%之光硬化性黏著片之光硬化而獲得完全硬化之黏著片。One embodiment of the adhesive sheet of the present invention is that the polymerization rate of the adhesive composition is about 99% or higher. Such a fully cured adhesive sheet can be obtained, for example, by photocuring the aforementioned semi-hardened adhesive sheet. A fully hardened adhesive sheet can also be obtained by photocuring a photohardenable adhesive sheet with a polymerization rate of less than 90%.

完全硬化之黏著片之玻璃轉移溫度較佳為-3℃以下。完全硬化之黏著片之溫度25℃下之剪切儲存彈性模數G'_{25 ℃} 較佳為0.16 MPa以上。完全硬化之黏著片之損失正切之峰頂值較佳為1.5以上。半硬化之黏著片較佳為藉由硬化而將聚合率提高至99%時之玻璃轉移溫度以及G'_{25 ℃} 在上述範圍內並且較佳為損失正切之峰頂值在上述範圍內。The glass transition temperature of the fully hardened adhesive sheet is preferably below -3°C. The shear storage elastic modulus G' ₂₅ °C of the fully hardened adhesive sheet at a temperature of 25 _°C is preferably 0.16 MPa or more. The peak value of the loss tangent of the fully hardened adhesive sheet is preferably 1.5 or more. For the semi-cured adhesive sheet, it is preferable that the glass transition temperature and G' _{25 °C} when the polymerization rate is increased to 99% by hardening are within the above range and the peak value of the loss tangent is preferably within the above range.

作為黏著片中所含有之基礎聚合物，例如使用將丙烯酸系聚合物鏈藉由胺基甲酸酯系鏈段進行交聯而獲得之聚合物。為了滿足上述各種特性，胺基甲酸酯系鏈段之含量相對於丙烯酸系聚合物鏈100重量份，較佳為3～30重量份。胺基甲酸酯系鏈段之重量平均分子量較佳為4000～50000。As the base polymer contained in the adhesive sheet, for example, a polymer obtained by cross-linking an acrylic polymer chain through a urethane-based segment is used. In order to satisfy the above-mentioned various characteristics, the content of the urethane-based segment is preferably 3 to 30 parts by weight relative to 100 parts by weight of the acrylic polymer chain. The weight average molecular weight of the urethane-based segment is preferably from 4,000 to 50,000.

將丙烯酸係聚合物鏈藉由胺基甲酸酯系鏈段進行交聯而成之基礎聚合物例如係藉由構成丙烯酸系聚合物鏈之單體成分與至少於兩個末端具有(甲基)丙烯醯基之胺基甲酸酯(甲基)丙烯酸酯之共聚而獲得。作為多官能胺基甲酸酯(甲基)丙烯酸酯，較佳為於兩末端具有(甲基)丙烯醯基之二胺基甲酸酯(甲基)丙烯酸酯。The base polymer formed by cross-linking the acrylic polymer chain through the urethane segment is, for example, composed of monomer components constituting the acrylic polymer chain and at least two ends having (methyl) Obtained by copolymerization of acrylic urethane (meth)acrylate. As polyfunctional urethane (meth)acrylate, the diurethane (meth)acrylate which has (meth)acryloyl group in both terminals is preferable.

胺基甲酸酯(甲基)丙烯酸酯之重量平均分子量較佳為4000～50000。胺基甲酸酯(甲基)丙烯酸酯之玻璃轉移溫度較佳為0℃以下。The weight average molecular weight of the urethane (meth)acrylate is preferably from 4,000 to 50,000. The glass transition temperature of urethane (meth)acrylate is preferably 0°C or lower.

含有將丙烯酸系聚合物鏈藉由胺基甲酸酯系鏈段進行交聯而成之基礎聚合物之黏著片例如藉由如下方式獲得，將含有丙烯酸系單體及/或其部分聚合物、以及胺基甲酸酯(甲基)丙烯酸酯之組合物以層狀塗佈於基材上，然後對組合物照射活性光線而進行光硬化。黏著劑組合物中，胺基甲酸酯(甲基)丙烯酸酯之含量相對於丙烯酸系單體及其部分聚合物之合計100重量份，較佳為3～30重量份。An adhesive sheet comprising a base polymer in which acrylic polymer chains are cross-linked through urethane segments can be obtained by, for example, comprising an acrylic monomer and/or a partial polymer thereof, And the composition of urethane (meth)acrylate is coated on the substrate in a layered form, and then the composition is irradiated with active light to be photohardened. In the adhesive composition, the content of the urethane (meth)acrylate is preferably 3 to 30 parts by weight relative to 100 parts by weight of the total of the acrylic monomer and its partial polymer.

本發明之黏著片例如用於在視認側表面配置有透明構件之圖像顯示裝置中之透明構件之貼合。於使用半硬化黏著片之情形時，藉由使黏著片與上述透明構件貼合，然後對黏著片照射活性光線，而進行黏著片之光硬化，藉此能夠形成圖像顯示裝置。 [發明之效果]The adhesive sheet of this invention is used, for example for bonding the transparent member in the image display apparatus which arrange|positioned the transparent member on the viewing side surface. In the case of using a semi-cured adhesive sheet, an image display device can be formed by bonding the adhesive sheet to the above-mentioned transparent member, and then irradiating the adhesive sheet with active light to photocure the adhesive sheet. [Effect of Invention]

本發明之黏著片由於完全硬化後之玻璃轉移溫度較低、並且剪切儲存彈性模數較大，故而，能夠於較寬之溫度範圍內兼具落下等耐衝擊性及對於變形應力之接著耐久性。另外，於半硬化之狀態下，剪切儲存彈性模數較小，因此階差吸收性優異。使用本發明之黏著片於視認側表面貼合有覆蓋窗口等之圖像顯示裝置之接著可靠性優異，亦能夠應對窄框緣化或無邊框化。The adhesive sheet of the present invention has a lower glass transition temperature after complete hardening and a larger shear storage elastic modulus, so it can have both impact resistance such as drop and durability against deformation stress in a wide temperature range sex. In addition, in the semi-cured state, the shear storage elastic modulus is small, so the step absorption is excellent. Using the adhesive sheet of the present invention, an image display device having a cover window and the like bonded to the surface on the viewing side has excellent adhesion reliability, and can also be adapted to narrow or borderless frames.

圖1表示於黏著片5之兩面暫時附著有離型膜1、2之附離型膜之黏著片。圖2係表示使用黏著片固定前面透明板7之圖像顯示裝置之構成例的剖視圖。FIG. 1 shows an adhesive sheet with a release film in which release films 1 and 2 are temporarily attached to both sides of an adhesive sheet 5 . FIG. 2 is a cross-sectional view showing a configuration example of an image display device in which a front transparent plate 7 is fixed using an adhesive sheet.

[黏著片之物性] 本發明之黏著片係將黏著劑以片狀形成之黏著片。黏著片係霧度為1.0%以下之透明黏著片。[Physical Properties of Adhesive Sheets] The adhesive sheet of the present invention is an adhesive sheet formed of an adhesive in a sheet form. The adhesive sheet is a transparent adhesive sheet with a haze of 1.0% or less.

於一實施形態中，構成黏著片之黏著劑為含有具有光聚合性官能基之單體或低聚物(光聚合性化合物)之光硬化性黏著劑。光硬化性黏著片之聚合率較佳為90～98%。換言之，光硬化性黏著片較佳為半硬化狀態，並且含有2～10重量%之光聚合性化合物。黏著片之聚合率係由將黏著片於130℃下加熱3小時之時之加熱前後的重量，根據下述式計算。後述之預聚物之聚合率亦藉由同樣之方法計算。 聚合率(%)＝乾燥後之重量/乾燥前之重量×100In one embodiment, the adhesive constituting the adhesive sheet is a photocurable adhesive containing a monomer or oligomer (photopolymerizable compound) having a photopolymerizable functional group. The polymerization rate of the photocurable adhesive sheet is preferably 90-98%. In other words, the photocurable adhesive sheet is preferably in a semi-cured state and contains 2 to 10% by weight of a photopolymerizable compound. The polymerization rate of the adhesive sheet was calculated from the weight before and after heating when the adhesive sheet was heated at 130° C. for 3 hours, according to the following formula. The polymerization rate of the prepolymer mentioned later was also calculated by the same method. Polymerization rate (%) = weight after drying/weight before drying x 100

就使黏著片具有階差吸收性、防止氣泡於印刷階差附近混入之觀點而言，半硬化之黏著片之溫度25℃下之剪切儲存彈性模數G'_{25 ℃} 較佳為0.15 MPa以下。另一方面，就黏著片之成型性、或操作性之觀點而言，半硬化黏著片之G'_{25 ℃} 較佳為0.03 MPa以上，更佳為0.05 MPa以上，進而較佳為0.07 MPa以上。From the viewpoint of making the adhesive sheet have step absorption and preventing the mixing of air bubbles near the printing step, the shear storage elastic modulus G' 25 °C of the semi-hardened adhesive sheet at a temperature of ₂₅ ° _C is preferably 0.15 MPa or less . On the other hand, from the viewpoint of formability or handleability of the adhesive sheet, the G' _{25 °C} of the semi-hardened adhesive sheet is preferably 0.03 MPa or higher, more preferably 0.05 MPa or higher, and still more preferably 0.07 MPa or higher.

若使半硬化黏著片與被接著體貼合後進行光硬化(後硬化)，則聚合率藉由光聚合性化合物之聚合反應而上升，黏著片之剪切儲存彈性模數增加。藉由後硬化獲得之完全硬化後(將聚合率設為99%以上之情形)之黏著片之25℃下之剪切儲存彈性模數G'_{25 ℃} 較佳為0.16 MPa以上。藉由完全硬化後之黏著片之G'_{25 ℃} 為0.16 MPa以上，接著可靠性提高。就提高高溫下之接著可靠性之觀點而言，完全硬化後之黏著片之80℃下之剪切儲存彈性模數G'_{80 ℃} 較佳為0.11 MPa以上。If the semi-hardened adhesive sheet is attached to the substrate and then photocured (post-cured), the polymerization rate will increase due to the polymerization reaction of the photopolymerizable compound, and the shear storage elastic modulus of the adhesive sheet will increase. The shear storage elastic modulus G' 25° C. of the adhesive sheet after complete hardening (when the polymerization rate is set to 99% or more) obtained by post-curing is preferably 0.16 MPa or more at _{25 ° C.} When the G' _{25 °C} of the adhesive sheet after complete hardening is 0.16 MPa or more, the subsequent reliability is improved. From the viewpoint of improving adhesive reliability at high temperatures, the shear storage elastic modulus G' ₈₀ °C of the fully cured adhesive sheet at 80 _° C is preferably 0.11 MPa or more.

另一方面，就使黏著片具有適度之黏性而確保潤濕性之觀點而言，完全硬化後之黏著片之G'_{25 ℃} 較佳為1 MPa以下，更佳為0.5 MPa以下，進而較佳為0.4 MPa以下。就同樣之觀點而言，完全硬化後之黏著片之G'_{80 ℃} 較佳為0.6 MPa以下，更佳為0.4 MPa以下，進而較佳為0.3 MPa以下。On the other hand, from the viewpoint of making the adhesive sheet moderately viscous and ensuring wettability, the G' _{25 °C} of the adhesive sheet after complete hardening is preferably 1 MPa or less, more preferably 0.5 MPa or less, and even more preferably Preferably, it is 0.4 MPa or less. From the same viewpoint, the G' _{80 °C} of the fully cured adhesive sheet is preferably 0.6 MPa or less, more preferably 0.4 MPa or less, and still more preferably 0.3 MPa or less.

半硬化黏著片之玻璃轉移溫度較佳為-5℃以下。半硬化黏著片之玻璃轉移溫度較佳為-25℃以上，更佳為-20℃以上，進而較佳為-18℃以上。完全硬化後之黏著片之玻璃轉移溫度較佳為-3℃以下。完全硬化後之黏著片之玻璃轉移溫度較佳為-20℃以上，更佳為-15℃以上，進而較佳為-13℃以上。藉由玻璃轉移溫度在上述範圍內，即便於低溫範圍內黏著片亦具有適當之黏性，故而有耐衝擊性優異之傾向。The glass transition temperature of the semi-hardened adhesive sheet is preferably below -5°C. The glass transition temperature of the semi-cured adhesive sheet is preferably -25°C or higher, more preferably -20°C or higher, and still more preferably -18°C or higher. The glass transition temperature of the fully hardened adhesive sheet is preferably below -3°C. The glass transition temperature of the fully cured adhesive sheet is preferably -20°C or higher, more preferably -15°C or higher, further preferably -13°C or higher. Since the glass transition temperature is within the above range, the adhesive sheet has appropriate viscosity even in the low temperature range, and therefore tends to be excellent in impact resistance.

半硬化黏著片之損失正切tanδ之峰頂值(即，玻璃轉移溫度下之tanδ)較佳為1.6以上，更佳為1.7以上，進而較佳為1.8以上。完全硬化後之黏著片之tanδ之峰頂值較佳為1.5以上，更佳為1.6以上，進而較佳為1.7以上。tanδ之峰頂值較大之黏著片有黏性行為較大、耐衝擊性優異之傾向。The peak value of the loss tangent tanδ of the semi-hardened adhesive sheet (ie, tanδ at the glass transition temperature) is preferably 1.6 or higher, more preferably 1.7 or higher, and still more preferably 1.8 or higher. The peak value of tanδ of the fully cured adhesive sheet is preferably at least 1.5, more preferably at least 1.6, and still more preferably at least 1.7. An adhesive sheet with a larger peak value of tan δ tends to have a larger sticky behavior and excellent impact resistance.

黏著片之剪切儲存彈性模數G'、玻璃轉移溫度以及tanδ之峰頂值藉由頻率1 Hz之黏彈性測定求出。玻璃轉移溫度為tanδ達到極大時之溫度(峰頂溫度)。tanδ為損失彈性模數G''對儲存彈性模數G'之比G''/G'。儲存彈性模數G'相當於材料發生變形時作為彈性能量而儲存之部分，係表示硬度之程度之指標。若黏著片之儲存彈性模數越大，則接著保持力越高，有於抑制因變形引起之剝離之傾向。損失彈性模數G''相當於材料發生變形時因內部摩擦等而散失之損失能量部分，表示黏性之程度。tanδ越大，則黏性之傾向越強，變形行為變為液體性行為，有回彈性能量減小之傾向。The shear storage elastic modulus G', glass transition temperature, and peak-top value of tanδ of the adhesive sheet were determined by viscoelasticity measurement at a frequency of 1 Hz. The glass transition temperature is the temperature (peak top temperature) at which tan δ reaches its maximum value. tan δ is the ratio G''/G' of the loss elastic modulus G'' to the storage elastic modulus G'. The storage elastic modulus G' is equivalent to the part stored as elastic energy when the material is deformed, and it is an index indicating the degree of hardness. The larger the storage elastic modulus of the adhesive sheet, the higher the adhesive holding force, which tends to suppress peeling due to deformation. The loss elastic modulus G'' is equivalent to the loss of energy due to internal friction when the material is deformed, indicating the degree of viscosity. The larger the tanδ, the stronger the viscous tendency, the deformation behavior becomes liquid behavior, and the rebound elastic energy tends to decrease.

對於半硬化之黏著片以及完全硬化後之黏著片中之任一者而言，tanδ之峰頂值之上限並無特別限制，通常為3.0以下。就接著保持力之觀點而言，tanδ之峰頂值較佳為2.7以下，更佳為2.5以下。For either the semi-cured adhesive sheet or the fully cured adhesive sheet, the upper limit of the peak value of tan δ is not particularly limited, and is usually 3.0 or less. From the viewpoint of adhesion retention, the peak value of tanδ is preferably 2.7 or less, more preferably 2.5 or less.

半硬化黏著片之接著力較佳為3 N/10 mm以上，更佳為4 N/10 mm以上，進而較佳為5 N/10 mm以上。藉由半硬化黏著片之接著力在上述範圍內，於將暫時附著於黏著片5之一個面之離型膜2(輕剝離膜)剝離而貼合於被接著體，然後將暫時附著於另一個面之離型膜1(重剝離膜)剝離時，能夠抑制被接著體與黏著片5之界面之剝離。The adhesive force of the semi-cured adhesive sheet is preferably at least 3 N/10 mm, more preferably at least 4 N/10 mm, and still more preferably at least 5 N/10 mm. With the adhesive force of the semi-hardened adhesive sheet within the above range, the release film 2 (light release film) temporarily attached to one side of the adhesive sheet 5 is peeled off and attached to the adherend, and then temporarily attached to the other side. When the release film 1 (heavy release film) on one side is peeled off, the peeling at the interface between the adherend and the adhesive sheet 5 can be suppressed.

完全硬化後之黏著片之接著力較佳為2 N/10 mm以上，更佳為2.5 N/10 mm以上，進而較佳為3 N/10 mm以上。藉由完全硬化後之黏著片之接著力在上述範圍內，能夠防止於產生由變形引起之應力、或由落下等引起之衝擊之情形時之黏著片自被接著體之剝離。The adhesive force of the fully cured adhesive sheet is preferably at least 2 N/10 mm, more preferably at least 2.5 N/10 mm, and still more preferably at least 3 N/10 mm. When the adhesive force of the fully cured adhesive sheet is within the above range, it is possible to prevent the peeling of the adhesive sheet from the adherend when stress due to deformation or impact due to drop occurs.

接著力係以玻璃板作為被接著體，藉由拉伸速度為60 mm/分鐘、剝離角度為180°之剝離試驗求出。只要無特別說明，接著力為25℃下之測定值。Adhesive force is determined by a peeling test with a glass plate as an adherend at a tensile speed of 60 mm/min and a peeling angle of 180°. Unless otherwise specified, the adhesive force is the measured value at 25°C.

半硬化黏著片之65℃下之接著力較佳為1 N/10 mm以上，更佳為1.5 N/10 mm以上，進而較佳為2 N/10 mm以上。完全硬化後之黏著片之65℃下之接著力較佳為1 N/10 mm以上，更佳為1.5 N/10 mm以上，進而較佳為2 N/10 mm以上。The adhesion force at 65°C of the semi-cured adhesive sheet is preferably at least 1 N/10 mm, more preferably at least 1.5 N/10 mm, and still more preferably at least 2 N/10 mm. The adhesive force at 65°C of the fully cured adhesive sheet is preferably at least 1 N/10 mm, more preferably at least 1.5 N/10 mm, and still more preferably at least 2 N/10 mm.

黏著片之厚度並無特別限制，根據被接著體之種類、或形狀等來設定即可。以如前面透明板般具有印刷階差之構件作為被接著體之情形時，較佳為黏著片之厚度大於印刷階差之厚度。用於貼合前面透明板(覆蓋窗口)之黏著片之厚度較佳為30 μm以上，更佳為40 μm以上，進而較佳為50 μm以上。藉由增大黏著片之厚度，有階差吸收性以及耐衝擊性升高之傾向。黏著片之厚度之上限並無特別限制，就黏著片之生產性等觀點而言，較佳為500 μm以下，更佳為300 μm以下，進而較佳為250 μm以下。The thickness of the adhesive sheet is not particularly limited, and may be set according to the type or shape of the adherend. In the case of using a member having printing steps like the transparent plate above as the adherend, it is preferable that the thickness of the adhesive sheet is greater than the thickness of the printing steps. The thickness of the adhesive sheet for laminating the front transparent plate (covering the window) is preferably at least 30 μm, more preferably at least 40 μm, and even more preferably at least 50 μm. By increasing the thickness of the adhesive sheet, the step absorption and impact resistance tend to increase. The upper limit of the thickness of the adhesive sheet is not particularly limited, but it is preferably 500 μm or less, more preferably 300 μm or less, and further preferably 250 μm or less from the viewpoint of the productivity of the adhesive sheet.

[黏著劑之組成] 本發明之黏著片只要滿足上述特性，則黏著劑之組成並無特別限制，可適當地選擇使用以丙烯酸系聚合物、聚矽氧系聚合物、聚酯、聚胺基甲酸酯、聚醯胺、聚乙烯醚、乙酸乙烯酯/氯乙烯共聚物、改性聚烯烴、環氧系、氟系、天然橡膠、合成橡膠等橡膠系等聚合物作為基礎聚合物之黏著劑。[Composition of Adhesive] As long as the adhesive sheet of the present invention satisfies the above characteristics, the composition of the adhesive is not particularly limited, and acrylic polymers, polysiloxane polymers, polyesters, polyurethanes, polyamides, etc. can be selected and used appropriately. Amine, polyvinyl ether, vinyl acetate/vinyl chloride copolymer, modified polyolefin, epoxy, fluorine, natural rubber, synthetic rubber and other rubber-based polymers are used as adhesives for the base polymer.

特別是，就光學透明性優異、顯示出適度之潤濕性、凝集性以及接著性等黏著特性，並且耐候性、或耐熱性等亦優異而言，較佳使用含有丙烯酸系聚合物作為基礎聚合物之丙烯酸系黏著劑。其中，較佳為具有將丙烯酸系聚合物鏈藉由胺基甲酸酯系鏈段進行交聯之結構之丙烯酸系基礎聚合物。In particular, it is preferable to use an acrylic polymer as the base polymer because it has excellent optical transparency, exhibits moderate wettability, cohesiveness, adhesiveness, and other adhesive properties, and is also excellent in weather resistance or heat resistance. Acrylic adhesive for objects. Among them, an acrylic base polymer having a structure in which acrylic polymer chains are cross-linked via a urethane-based segment is preferable.

[基礎聚合物] 丙烯酸系聚合物鏈藉由胺基甲酸酯系鏈段進行交聯，藉此於低玻璃轉移溫度下能夠實現較高之接著保持力。於基礎聚合物中，相對於丙烯酸系聚合物鏈100重量份，較佳為胺基甲酸酯系鏈段之含量為3重量份以上。[Base Polymer] The acrylic polymer chains are cross-linked by urethane segments, thereby enabling higher adhesive retention at low glass transition temperatures. In the base polymer, the content of the urethane-based segment is preferably 3 parts by weight or more relative to 100 parts by weight of the acrylic polymer chain.

若胺基甲酸酯系鏈段之量過度增大，則有時黏著劑之黏性隨著交聯密度之上升而降低，並且階差吸收性、或耐衝擊性降低。另外，若胺基甲酸酯系鏈段之量過度增大，則有時黏著片之透明性降低、霧度上升。因此，基礎聚合物中之胺基甲酸酯系鏈段之量相對於丙烯酸系聚合物鏈100重量份，較佳為30重量份以下，更佳為25重量份以下。When the amount of the urethane-based segment is excessively increased, the viscosity of the adhesive may decrease as the crosslinking density increases, and the step absorption or impact resistance may decrease. Moreover, when the quantity of a urethane system segment increases too much, the transparency of an adhesive sheet may fall and haze may rise. Therefore, the amount of the urethane-based segment in the base polymer is preferably 30 parts by weight or less, more preferably 25 parts by weight or less, based on 100 parts by weight of the acrylic polymer chain.

＜丙烯酸系聚合物鏈＞ 丙烯酸系聚合物鏈含有(甲基)丙烯酸烷基酯作為主要構成單體成分。再者，於本說明書中，所謂「(甲基)丙烯酸」係指丙烯酸及/或甲基丙烯酸。＜Acrylic polymer chain＞ The acrylic polymer chain contains an alkyl (meth)acrylate as a main constituent monomer component. In addition, in this specification, "(meth)acrylic acid" means acrylic acid and/or methacrylic acid.

作為(甲基)丙烯酸烷基酯，較佳使用烷基之碳數為1～20之(甲基)丙烯酸烷基酯。(甲基)丙烯酸烷基酯中，烷基可具有支鏈，亦可具有環狀烷基。As the alkyl (meth)acrylate, an alkyl (meth)acrylate having 1 to 20 carbon atoms in the alkyl group is preferably used. In the alkyl (meth)acrylate, the alkyl group may have a branched chain or may have a cyclic alkyl group.

作為具有鏈狀烷基之(甲基)丙烯酸烷基酯之具體例，可列舉：(甲基)丙烯酸甲酯、(甲基)丙烯酸乙酯、(甲基)丙烯酸丁酯、(甲基)丙烯酸異丁酯、(甲基)丙烯酸第二丁酯、(甲基)丙烯酸第三丁酯、(甲基)丙烯酸戊酯、(甲基)丙烯酸異戊酯、(甲基)丙烯酸新戊酯、(甲基)丙烯酸己酯、(甲基)丙烯酸庚酯、(甲基)丙烯酸2-乙基己基酯、(甲基)丙烯酸辛酯、(甲基)丙烯酸異辛酯、(甲基)丙烯酸壬酯、(甲基)丙烯酸異壬酯、(甲基)丙烯酸癸基酯、(甲基)丙烯酸異癸基酯、(甲基)丙烯酸十一烷基酯、(甲基)丙烯酸十二烷基酯、(甲基)丙烯酸異十三烷基酯、(甲基)丙烯酸十四烷基酯、(甲基)丙烯酸異十四烷基酯、(甲基)丙烯酸十五烷基酯、(甲基)丙烯酸十六烷基酯、(甲基)丙烯酸十七烷基酯、(甲基)丙烯酸十八烷基酯、(甲基)丙烯酸異十八烷基酯、(甲基)丙烯酸十九烷基酯等。Specific examples of alkyl (meth)acrylates having a chain alkyl group include: methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, (meth)acrylate Isobutyl acrylate, second butyl (meth)acrylate, third butyl (meth)acrylate, amyl (meth)acrylate, isopentyl (meth)acrylate, neopentyl (meth)acrylate , Hexyl (meth)acrylate, Heptyl (meth)acrylate, 2-Ethylhexyl (meth)acrylate, Octyl (meth)acrylate, Isooctyl (meth)acrylate, (Meth) Nonyl acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, lauryl (meth)acrylate Alkyl esters, Isotridecyl (meth)acrylate, Myristyl (meth)acrylate, Isotetradecyl (meth)acrylate, Pentadecyl (meth)acrylate, Cetyl (meth)acrylate, Heptadecyl (meth)acrylate, Octadecyl (meth)acrylate, Isostearyl (meth)acrylate, (Meth)acrylic acid Nonadecyl ester, etc.

作為具有脂環式烷基之(甲基)丙烯酸烷基酯之具體例，可列舉：(甲基)丙烯酸環戊酯、(甲基)丙烯酸環己酯、(甲基)丙烯酸環庚酯、(甲基)丙烯酸環辛酯等(甲基)丙烯酸環烷基酯；(甲基)丙烯酸異𦯉基酯等具有二環式脂肪族烴環之(甲基)丙烯酸酯；(甲基)丙烯酸二環戊酯、(甲基)丙烯酸二環戊氧基乙基酯、(甲基)丙烯酸三環戊酯、(甲基)丙烯酸1-金剛烷基酯、(甲基)丙烯酸2-甲基-2-金剛烷基酯、(甲基)丙烯酸2-乙基-2-金剛烷基酯等具有三環以上脂肪族烴環之(甲基)丙烯酸酯。Specific examples of alkyl (meth)acrylates having an alicyclic alkyl group include cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, cycloheptyl (meth)acrylate, Cycloalkyl (meth)acrylates such as cyclooctyl (meth)acrylate; (meth)acrylates with bicyclic aliphatic hydrocarbon rings such as iso(meth)acrylate; (meth)acrylic acid Dicyclopentyl, Dicyclopentyloxyethyl (meth)acrylate, Tricyclopentyl (meth)acrylate, 1-adamantyl (meth)acrylate, 2-methyl (meth)acrylate - (meth)acrylates having aliphatic hydrocarbon rings having three or more rings, such as 2-adamantyl ester and 2-ethyl-2-adamantyl (meth)acrylate.

相對於構成丙烯酸系聚合物鏈之單體成分總量，(甲基)丙烯酸烷基酯之量較佳為40重量%以上，更佳為50重量%以上，進而較佳為60重量%以上。就將聚合物鏈之玻璃轉移溫度(Tg)設為適當之範圍內之觀點而言，於丙烯酸系聚合物鏈中，具有碳數4～10之鏈狀烷基之(甲基)丙烯酸烷基酯之量相對於構成單體成分總量，較佳為30重量%以上，更佳為40重量%以上，進而較佳為45重量%以上。再者，所謂構成丙烯酸系聚合物鏈之單體成分係指除了作為胺基甲酸酯系鏈段之構成成分之胺基甲酸酯(甲基)丙烯酸酯等以外之單體成分。The amount of the alkyl (meth)acrylate is preferably at least 40% by weight, more preferably at least 50% by weight, and still more preferably at least 60% by weight, based on the total amount of monomer components constituting the acrylic polymer chain. From the viewpoint of setting the glass transition temperature (Tg) of the polymer chain within an appropriate range, in the acrylic polymer chain, the (meth)acrylic acid alkyl group having a chain alkyl group having 4 to 10 carbon atoms The amount of the ester is preferably at least 30% by weight, more preferably at least 40% by weight, and still more preferably at least 45% by weight, based on the total amount of the constituent monomer components. In addition, the term "monomer components constituting an acrylic polymer chain" refers to monomer components other than urethane (meth)acrylate, etc., which are constituent components of a urethane-based segment.

丙烯酸系聚合物鏈可含有含羥基之單體、或含羧基之單體作為構成單體成分。丙烯酸系聚合物鏈藉由具有含羥基之單體作為構成單體成分，有能夠提高黏著片之透明性，並且抑制高溫高濕環境下之白濁之傾向。The acrylic polymer chain may contain a hydroxyl group-containing monomer or a carboxyl group-containing monomer as a constituent monomer component. The acrylic polymer chain has a hydroxyl group-containing monomer as a constituent monomer component, which can improve the transparency of the adhesive sheet and suppress the tendency of white turbidity in a high-temperature and high-humidity environment.

作為含羥基之單體，可列舉：(甲基)丙烯酸2-羥基乙基酯、(甲基)丙烯酸2-羥基丙基酯、(甲基)丙烯酸4-羥基丁基酯、(甲基)丙烯酸6-羥基己基酯、(甲基)丙烯酸8-羥基辛基酯、(甲基)丙烯酸10-羥基癸基酯、(甲基)丙烯酸12-羥基月桂酯、或(甲基)丙烯酸(4-羥甲基環己基)甲酯等(甲基)丙烯酸酯。其中，就與胺基甲酸酯系鏈段之相容性較高且提高黏著片之透明性之觀點而言，丙烯酸系聚合物鏈較佳為含有具有碳數4～8之羥基烷基之(甲基)丙烯酸酯作為構成單體成分。Examples of hydroxyl-containing monomers include: 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, (meth) 6-Hydroxyhexyl acrylate, 8-Hydroxyoctyl (meth)acrylate, 10-Hydroxydecyl (meth)acrylate, 12-Hydroxylauryl (meth)acrylate, or (4 -(meth)acrylates such as hydroxymethylcyclohexyl)methyl ester. Among them, the acrylic polymer chain is preferably one containing a hydroxyalkyl group having 4 to 8 carbon atoms, from the viewpoint of high compatibility with the urethane-based chain segment and improving the transparency of the adhesive sheet. (Meth)acrylate is used as a constituent monomer component.

含羥基單體之量相對於構成丙烯酸系聚合物鏈之單體成分總量，較佳為1～35重量%，更佳為3～30重量%，進而較佳為5～25重量%。The amount of the hydroxyl group-containing monomer is preferably 1 to 35% by weight, more preferably 3 to 30% by weight, and still more preferably 5 to 25% by weight, based on the total amount of monomer components constituting the acrylic polymer chain.

作為含羧基之單體，可列舉：(甲基)丙烯酸、(甲基)丙烯酸羧基乙基酯、(甲基)丙烯酸羧基戊基酯等丙烯酸系單體或衣康酸、馬來酸、富馬酸、巴豆酸等。Examples of carboxyl group-containing monomers include acrylic monomers such as (meth)acrylic acid, carboxyethyl (meth)acrylate, and carboxypentyl (meth)acrylate, or itaconic acid, maleic acid, Maic acid, crotonic acid, etc.

丙烯酸系聚合物鏈可含有含氮之單體作為構成單體成分。作為含氮之單體，可列舉：N-乙烯基吡咯烷酮、甲基乙烯基吡咯烷酮、乙烯基吡啶、乙烯基哌啶酮、乙烯基嘧啶、乙烯基哌嗪、乙烯基吡嗪、乙烯基吡咯、乙烯基咪唑、乙烯基㗁唑、乙烯基嗎啉、(甲基)丙烯醯嗎啉、N-乙烯基羧醯胺類、N-乙烯基己內醯胺等乙烯系單體、或丙烯腈、甲基丙烯腈等含氰基之丙烯酸系單體等。The acrylic polymer chain may contain a nitrogen-containing monomer as a constituent monomer component. Examples of nitrogen-containing monomers include N-vinylpyrrolidone, methylvinylpyrrolidone, vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, Vinylimidazole, vinyl azole, vinyl morpholine, (meth)acryl morpholine, N-vinyl carboxamides, N-vinyl caprolactam and other vinyl monomers, or acrylonitrile, Acrylic monomers containing cyano groups such as methacrylonitrile, etc.

丙烯酸系聚合物鏈藉由含有含羥基之單體、含羧基之單體等高極性單體作為構成單體成分，而能夠提高黏著劑之凝集力，有高溫下之接著保持性提高之傾向。另一方面，若高極性單體之含量過大，則玻璃轉移溫度升高，有時低溫下之接著性、或耐衝擊性降低。因此，高極性單體量(含羥基之單體、含羧基之單體以及含氮單體之合計)相對於構成丙烯酸系聚合物鏈之單體成分總量，較佳為3～40重量%，更佳為5～35重量%，進而較佳為10～30重量%。另外，含氮單體之量相對於構成丙烯酸系聚合物鏈之單體成分總量，較佳為1～25重量%，更佳為2～20重量%，進而較佳為3～15重量%。The acrylic polymer chain can improve the cohesive force of the adhesive by containing highly polar monomers such as hydroxyl-containing monomers and carboxyl-containing monomers as monomer components, and tends to improve the adhesion retention at high temperatures. On the other hand, if the content of the highly polar monomer is too large, the glass transition temperature will increase, and the adhesiveness at low temperature or the impact resistance may decrease. Therefore, the amount of highly polar monomers (the sum of hydroxyl-containing monomers, carboxyl-containing monomers, and nitrogen-containing monomers) is preferably 3 to 40% by weight relative to the total amount of monomer components constituting the acrylic polymer chain. , more preferably 5 to 35% by weight, and still more preferably 10 to 30% by weight. In addition, the amount of the nitrogen-containing monomer is preferably 1 to 25% by weight, more preferably 2 to 20% by weight, and still more preferably 3 to 15% by weight relative to the total amount of monomer components constituting the acrylic polymer chain. .

丙烯酸系聚合物鏈可含有含酸酐基之單體、(甲基)丙烯酸之己內酯加成物、含磺酸基之單體、含磷酸基之單體、乙酸乙烯酯、丙酸乙烯酯、苯乙烯、α-甲基苯乙烯等乙烯系單體；丙烯腈、甲基丙烯腈等含氰基之丙烯酸系單體；(甲基)丙烯酸縮水甘油酯等含環氧基之單體；(甲基)丙烯酸聚乙二醇酯、(甲基)丙烯酸聚丙二醇酯、(甲基)丙烯酸甲氧基乙二醇酯、(甲基)丙烯酸甲氧基聚丙二醇酯等二醇系丙烯酸酯單體；(甲基)丙烯酸四氫糠酯、氟(甲基)丙烯酸酯、聚矽氧(甲基)丙烯酸酯、(甲基)丙烯酸2-甲氧基乙酯等丙烯酸酯系單體等作為上述以外之單體成分。Acrylic polymer chains can contain monomers containing anhydride groups, caprolactone adducts of (meth)acrylic acid, monomers containing sulfonic acid groups, monomers containing phosphoric acid groups, vinyl acetate, vinyl propionate , styrene, α-methylstyrene and other vinyl monomers; cyano-containing acrylic monomers such as acrylonitrile and methacrylonitrile; (meth)glycidyl acrylate and other epoxy-containing monomers; Glycol-based acrylates such as polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, methoxyethylene glycol (meth)acrylate, and methoxypolypropylene glycol (meth)acrylate Monomer: tetrahydrofurfuryl (meth)acrylate, fluorine (meth)acrylate, polysiloxane (meth)acrylate, 2-methoxyethyl (meth)acrylate and other acrylate monomers, etc. As a monomer component other than the above.

丙烯酸系聚合物鏈可含有多官能單體或低聚物。多官能化合物於一個分子中含有兩個以上(甲基)丙烯醯基或乙烯基等具有不飽和雙鍵之聚合性官能基。作為多官能化合物，可列舉：聚乙二醇二(甲基)丙烯酸酯、聚丙二醇二(甲基)丙烯酸酯、聚丁二醇二(甲基)丙烯酸酯、雙酚A環氧乙烷改性二(甲基)丙烯酸酯、雙酚A環氧丙烷改性二(甲基)丙烯酸酯、烷二醇二(甲基)丙烯酸酯、三環癸烷二甲醇二(甲基)丙烯酸酯、乙氧基化異氰脲酸三丙烯酸酯、季戊四醇三(甲基)丙烯酸酯、季戊四醇二(甲基)丙烯酸酯、三羥甲基丙烷三(甲基)丙烯酸酯、二-三羥甲基丙烷四(甲基)丙烯酸酯、乙氧化季戊四醇四(甲基)丙烯酸酯、季戊四醇四(甲基)丙烯酸酯、二季戊四醇聚(甲基)丙烯酸酯、二季戊四醇六(甲基)丙烯酸酯、新戊二醇二(甲基)丙烯酸酯、甘油二(甲基)丙烯酸酯、環氧(甲基)丙烯酸酯、丁二烯(甲基)丙烯酸酯、異戊二烯(甲基)丙烯酸酯等。The acrylic polymer chain may contain multifunctional monomers or oligomers. A polyfunctional compound contains two or more polymerizable functional groups with unsaturated double bonds, such as (meth)acryl or vinyl groups, in one molecule. Examples of polyfunctional compounds include: polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polytetramethylene glycol di(meth)acrylate, bisphenol A modified ethylene oxide, Sexual di(meth)acrylate, bisphenol A propylene oxide modified di(meth)acrylate, alkanediol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, Ethoxylated isocyanurate triacrylate, pentaerythritol tri(meth)acrylate, pentaerythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, di-trimethylolpropane Tetra(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol poly(meth)acrylate, dipentaerythritol hexa(meth)acrylate, neopentyl Glycol di(meth)acrylate, glycerin di(meth)acrylate, epoxy (meth)acrylate, butadiene (meth)acrylate, isoprene (meth)acrylate, and the like.

藉由丙烯酸系聚合物鏈含有多官能單體作為構成單體成分，藉此於聚合物鏈導入支鏈結構(交聯結構)。如後所述，於本發明之黏著劑中，藉由胺基甲酸酯系鏈段於丙烯酸系聚合物鏈導入交聯結構。若由除胺基甲酸酯系鏈段以外之多官能單體成分引起之交聯結構之導入量增加，則有時黏著劑之低溫接著力降低。因此，多官能化合物(丙烯酸胺基甲酸酯除外)之量相對於構成丙烯酸系聚合物鏈之單體成分總量，較佳為3重量%以下，更佳為1重量%以下，進而較佳為0.5重量%以下，特別較佳為0.3重量%以下。When the acrylic polymer chain contains a polyfunctional monomer as a constituent monomer component, a branched structure (crosslinked structure) is introduced into the polymer chain. As will be described later, in the adhesive of the present invention, a crosslinked structure is introduced into the acrylic polymer chain through the urethane-based segment. When the introduction amount of the crosslinked structure caused by the multifunctional monomer components other than the urethane-based chain segment increases, the low-temperature adhesive force of the adhesive may decrease. Therefore, the amount of the polyfunctional compound (excluding urethane acrylate) is preferably 3% by weight or less, more preferably 1% by weight or less, and even more preferably 0.5% by weight or less, particularly preferably 0.3% by weight or less.

對於丙烯酸系聚合物鏈，於上述單體成分之中較佳為(甲基)丙烯酸烷基酯之含量最多。根據丙烯酸系聚合物鏈之構成單體中含量最多之單體(主要單體)之種類，容易控制黏著片之特性。例如，於丙烯酸系聚合物鏈之主要單體為具有碳數6以下之鏈狀烷基之(甲基)丙烯酸烷基酯之情形時，有tanδ之峰頂值增大、耐衝擊性提高之傾向。特別是於丙烯酸丁酯等丙烯酸C₄ 烷基酯為主要單體之情形時，有tanδ之峰頂值上升之傾向。相對於構成丙烯酸系聚合物鏈之單體成分總量，具有碳數6以下之鏈狀烷基之(甲基)丙烯酸烷基酯之量，較佳為30重量%～80重量%，更佳為35重量%～75重量%，進而較佳為40重量%～70重量%。特別是較佳為作為構成單體成分之丙烯酸丁酯之含量在上述範圍內。For the acrylic polymer chain, it is preferable that the content of the alkyl (meth)acrylate is the largest among the above-mentioned monomer components. It is easy to control the characteristics of the adhesive sheet according to the type of the most abundant monomer (main monomer) among the constituent monomers of the acrylic polymer chain. For example, when the main monomer of the acrylic polymer chain is an alkyl (meth)acrylate having a chain alkyl group having 6 or less carbon atoms, the peak value of tan δ increases and the impact resistance improves. tendency. Especially when _C4 alkyl acrylate such as butyl acrylate is the main monomer, the peak value of tan δ tends to increase. The amount of the alkyl (meth)acrylate having a chained alkyl group having 6 or less carbon atoms is preferably 30% by weight to 80% by weight, more preferably It is 35 weight% - 75 weight%, More preferably, it is 40 weight% - 70 weight%. In particular, it is preferable that the content of butyl acrylate as a constituent monomer component is within the above-mentioned range.

丙烯酸系聚合物鏈之理論Tg較佳為-50℃以上。丙烯酸系聚合物鏈之理論Tg較佳為-10℃以下，更佳為-20℃以下，進而較佳為-25℃以下。理論Tg係由丙烯酸系聚合物鏈之構成單體成分之均聚物之玻璃轉移溫度Tg_i 與各單體成分之重量分率W_i 利用下述Fox式計算出。 1/Tg＝Σ(W_i /Tg_i )The theoretical Tg of the acrylic polymer chain is preferably -50°C or higher. The theoretical Tg of the acrylic polymer chain is preferably -10°C or lower, more preferably -20°C or lower, further preferably -25°C or lower. Theoretical Tg is calculated from the glass transition temperature Tg _i of the homopolymer of monomer components constituting the acrylic polymer chain and the weight fraction W _i of each monomer component using the following Fox formula. 1/Tg＝Σ(W _i /Tg _i )

Tg為聚合物鏈之玻璃轉移溫度(單位：K)，W_i 為構成鏈段之單體成分i之重量分率(重量基準之共聚比例)，Tg_i 為單體成分i之均聚物之玻璃轉移溫度(單位：K)。作為均聚物之玻璃轉移溫度，可採用Polymer Handbook第3版(John Wiley & Sons, Inc., 1989年)中記載之數值。上述文獻中未記載之單體之均聚物之Tg只要採用由動態黏彈性測定得到之損失正切(tanδ)之峰頂溫度即可。Tg is the glass transition temperature of the polymer chain (unit: K), W _i is the weight fraction (copolymerization ratio on a weight basis) of the monomer component i constituting the chain segment, and Tg _i is the weight fraction of the homopolymer of the monomer component i Glass transition temperature (unit: K). As the glass transition temperature of a homopolymer, the value described in Polymer Handbook 3rd edition (John Wiley & Sons, Inc., 1989) can be used. For the Tg of homopolymers of monomers not described in the above documents, the peak top temperature of loss tangent (tan δ) obtained by dynamic viscoelasticity measurement may be used.

＜胺基甲酸酯系鏈段＞ 胺基甲酸酯系鏈段係具有胺基甲酸酯鍵之分子鏈，藉由胺基甲酸酯系鏈段之兩末端與丙烯酸系聚合物鏈共價鍵結，而於丙烯酸系聚合物鏈導入交聯結構。＜Urethane-based segment＞ The urethane-based segment is a molecular chain with a urethane bond, and the two ends of the urethane-based segment are covalently bonded to the acrylic polymer chain, and the acrylic polymer Chains lead into cross-linked structures.

(胺基甲酸酯系鏈段之結構) 胺基甲酸酯系鏈段典型而言包含可使二醇與二異氰酸酯反應之聚胺基甲酸酯鏈。就獲得能夠兼具低溫接著性及高溫保持力之黏著劑之觀點而言，胺基甲酸酯系鏈段中之聚胺基甲酸酯鏈之分子量較佳為4000～50000，更佳為4500～40000，進而較佳為5000～30000。(Structure of urethane chain segment) The urethane-based segments typically comprise polyurethane chains that allow diols to react with diisocyanates. From the viewpoint of obtaining an adhesive capable of both low-temperature adhesiveness and high-temperature retention, the molecular weight of the polyurethane chain in the urethane-based chain segment is preferably 4,000-50,000, more preferably 4,500 to 40000, more preferably 5000 to 30000.

胺基甲酸酯系鏈段中之聚胺基甲酸酯鏈之分子量越大，則丙烯酸系聚合物鏈之交聯點間距離越長。於聚胺基甲酸酯鏈之分子量過小而交聯點間距離較短之情形時，隨著凝集力之增大，儲存彈性模數增大。隨之，黏著片之黏性降低，tanδ降低，故而有階差吸收性、或耐衝擊性降低之傾向。於聚胺基甲酸酯鏈之分子量過大而交聯點間距離較長之情形時，有時儲存彈性模數較小、接著保持力不足。聚胺基甲酸酯鏈之分子量在上述範圍內之情形時，黏著劑具有適度之凝集性，因此能夠兼具耐衝擊性及接著保持力。The greater the molecular weight of the polyurethane chains in the urethane segment, the longer the distance between the crosslinking points of the acrylic polymer chains. When the molecular weight of the polyurethane chain is too small and the distance between the crosslinking points is short, the storage modulus of elasticity increases with the increase of the cohesive force. As a result, the viscosity of the adhesive sheet decreases, and tanδ decreases, so the step absorption or impact resistance tends to decrease. When the molecular weight of the polyurethane chain is too large and the distance between the crosslinking points is long, the storage elastic modulus may be small and the subsequent holding force may be insufficient. When the molecular weight of the polyurethane chain is within the above range, the adhesive has moderate cohesiveness, and thus can have both impact resistance and adhesive holding power.

作為用於形成聚胺基甲酸酯鏈之二醇，可列舉：乙二醇、二乙二醇、丙二醇、丁二醇、己二醇等低分子量二醇；聚酯多元醇、聚醚多元醇、聚碳酸酯多元醇、丙烯酸多元醇、環氧多元醇、己內酯多元醇等高分子量多元醇。Examples of diols used to form polyurethane chains include low-molecular-weight diols such as ethylene glycol, diethylene glycol, propylene glycol, butylene glycol, and hexylene glycol; polyester polyols, polyether polyols, etc. Alcohols, polycarbonate polyols, acrylic polyols, epoxy polyols, caprolactone polyols and other high molecular weight polyols.

聚醚多元醇係藉由於多元醇中開環加成聚合環氧烷而獲得。作為環氧烷，可列舉：環氧乙烷、環氧丙烷、環氧丁烷、氧化苯乙烯、四氫呋喃等。作為多元醇，可列舉上述二醇、或甘油、三羥甲基丙烷等。Polyether polyols are obtained by ring-opening addition polymerization of alkylene oxides to polyols. Examples of the alkylene oxide include ethylene oxide, propylene oxide, butylene oxide, styrene oxide, tetrahydrofuran, and the like. Examples of the polyhydric alcohol include the aforementioned diols, glycerin, trimethylolpropane, and the like.

聚酯多元醇係末端具有羥基之聚酯，藉由以使醇當量相對於羧酸當量過量之方式使多元酸與多元醇反應而獲得。作為構成聚酯多元醇之多元酸成分以及多元醇成分，較佳為二元酸與二醇之組合。The polyester polyol is a polyester having a hydroxyl group at the terminal, and is obtained by reacting a polybasic acid and a polyhydric alcohol so that the alcohol equivalent is in excess relative to the carboxylic acid equivalent. As the polybasic acid component and the polyol component constituting the polyester polyol, a combination of a dibasic acid and a diol is preferable.

作為二元酸成分，可列舉：鄰苯二甲酸、間苯二甲酸、對苯二甲酸等芳香族二羧酸；六氫鄰苯二甲酸、四氫鄰苯二甲酸、1,3-環己烷二甲酸、1,4-環己烷二甲酸等脂環式二羧酸；草酸、琥珀酸、丙二酸、戊二酸、己二酸、庚二酸、辛二酸、壬二酸、癸烷二甲酸、十二烷二甲酸、十四烷二甲酸、二十烷二甲酸等脂肪族二羧酸；該等二羧酸之酸酐、低級醇酯等。Examples of dibasic acid components include: aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid; hexahydrophthalic acid, tetrahydrophthalic acid, 1,3-cyclohexane Alicyclic dicarboxylic acids such as alkanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid; oxalic acid, succinic acid, malonic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, Aliphatic dicarboxylic acids such as decanedicarboxylic acid, dodecanedicarboxylic acid, tetradecanedicarboxylic acid, and eicosanedicarboxylic acid; anhydrides and lower alcohol esters of these dicarboxylic acids.

作為二醇成分，可列舉：乙二醇、1,2-丙二醇、1,3-丙二醇、1,3-丁二醇、1,4-丁二醇、新戊二醇、戊二醇、1,6-己二醇、1,8-辛二醇、1,10-癸二醇、二乙二醇、三乙二醇、聚乙二醇、二丙二醇、聚丙二醇、1,4-環己烷二甲醇、1,4-環己二醇、雙酚A、雙酚F、氫化雙酚A、氫化雙酚F等。Examples of the diol component include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, pentylene glycol, 1 ,6-hexanediol, 1,8-octanediol, 1,10-decanediol, diethylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, 1,4-cyclohexyl Alkanedimethanol, 1,4-cyclohexanediol, bisphenol A, bisphenol F, hydrogenated bisphenol A, hydrogenated bisphenol F, etc.

作為聚碳酸酯多元醇，可列舉使二醇成分與光氣進行縮聚反應而獲得之聚碳酸酯多元醇；使二醇成分與碳酸二甲酯、碳酸二乙酯、碳酸二丙酯、碳酸二異丙酯、碳酸二丁酯、碳酸乙基丁基酯、碳酸乙二酯、碳酸丙二酯、碳酸二苯酯、碳酸二苄酯等碳酸二酯類進行酯交換縮合而獲得之聚碳酸酯多元醇；併用兩種以上多元醇成分而獲得之共聚聚碳酸酯多元醇；使上述各種聚碳酸酯多元醇與含羧基之化合物進行酯化反應而獲得之聚碳酸酯多元醇；使上述各種聚碳酸酯多元醇與含羥基之化合物進行醚化反應而獲得之聚碳酸酯多元醇；使上述各種聚碳酸酯多元醇與酯化合物進行酯交換反應而獲得之聚碳酸酯多元醇；使上述各種聚碳酸酯多元醇與含羥基之化合物進行酯交換反應而獲得之聚碳酸酯多元醇；藉由上述各種聚碳酸酯多元醇與二羧酸化合物之縮聚而獲得之聚酯系聚碳酸酯多元醇；藉由使上述各種聚碳酸酯多元醇與環氧烷共聚而獲得之共聚聚醚系聚碳酸酯多元醇等。Examples of polycarbonate polyols include polycarbonate polyols obtained by polycondensing a diol component with phosgene; mixing diol components with dimethyl carbonate, diethyl carbonate, dipropyl carbonate, Polycarbonate obtained by transesterification condensation of carbonate diesters such as isopropyl, dibutyl carbonate, ethyl butyl carbonate, ethylene carbonate, propylene carbonate, diphenyl carbonate, and dibenzyl carbonate Polyols; copolycarbonate polyols obtained by using two or more polyol components; polycarbonate polyols obtained by esterifying the above-mentioned polycarbonate polyols with carboxyl-containing compounds; making the above-mentioned polycarbonate polyols Polycarbonate polyol obtained by etherification reaction between carbonate polyol and hydroxyl-containing compound; polycarbonate polyol obtained by transesterification reaction between the above polycarbonate polyol and ester compound; Polycarbonate polyols obtained by transesterification of carbonate polyols with hydroxyl-containing compounds; polyester polycarbonate polyols obtained by polycondensation of the above-mentioned various polycarbonate polyols and dicarboxylic acid compounds; Copolyether-based polycarbonate polyols obtained by copolymerizing the above-mentioned various polycarbonate polyols with alkylene oxide, and the like.

聚丙烯酸多元醇係藉由將(甲基)丙烯酸酯與具有羥基之單體成分進行共聚而獲得。作為具有羥基之單體，可列舉：(甲基)丙烯酸2-羥基乙酯、(甲基)丙烯酸2-羥基丙酯、(甲基)丙烯酸3-羥基丙酯、(甲基)丙烯酸2-羥基丁酯、(甲基)丙烯酸4-羥基丁酯、(甲基)丙烯酸2-羥基戊酯等(甲基)丙烯酸之羥基烷基酯；甘油、三羥甲基丙烷等多元醇之(甲基)丙烯酸單酯；N-羥甲基(甲基)丙烯醯胺等。作為(甲基)丙烯酸酯，可列舉：(甲基)丙烯酸甲酯、(甲基)丙烯酸丁酯、(甲基)丙烯酸2-乙基己基酯、(甲基)丙烯酸環己酯等。Polyacrylic polyols are obtained by copolymerizing (meth)acrylates with hydroxyl-containing monomer components. Examples of monomers having a hydroxyl group include: 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, Hydroxyalkyl esters of (meth)acrylic acid such as hydroxybutyl ester, 4-hydroxybutyl (meth)acrylate, and 2-hydroxypentyl (meth)acrylate; base) acrylate monoester; N-methylol (meth) acrylamide, etc. As (meth)acrylate, methyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl (meth)acrylate, etc. are mentioned.

聚丙烯酸多元醇可含有除上述以外之單體成分作為共聚成分。作為除上述以外之共聚單體成分，可列舉：(甲基)丙烯酸等不飽和一元羧酸；馬來酸等不飽和二元羧酸及其酸酐以及單酯或二酯類；(甲基)丙烯腈等不飽和腈類；(甲基)丙烯醯胺、N-羥甲基(甲基)丙烯醯胺等不飽和醯胺類；乙酸乙烯酯、丙酸乙烯酯等乙烯酯類；甲基乙烯醚等乙烯醚類；乙烯、丙烯等α-烯烴類；氯乙烯、偏二氯乙烯等鹵代α,β-不飽和脂肪族單體；苯乙烯、α-甲基苯乙烯等α,β-不飽和芳香族單體等。The polyacrylic polyol may contain monomer components other than the above as copolymerization components. Examples of comonomer components other than the above include unsaturated monocarboxylic acids such as (meth)acrylic acid; unsaturated dicarboxylic acids such as maleic acid and their anhydrides, and monoesters or diesters; Unsaturated nitriles such as acrylonitrile; unsaturated amides such as (meth)acrylamide and N-methylol(meth)acrylamide; vinyl esters such as vinyl acetate and vinyl propionate; methyl Vinyl ethers such as vinyl ether; α-olefins such as ethylene and propylene; halogenated α, β-unsaturated aliphatic monomers such as vinyl chloride and vinylidene chloride; α, β such as styrene and α-methylstyrene -Unsaturated aromatic monomers, etc.

作為用於形成聚胺基甲酸酯鏈之二異氰酸酯，可為芳香族二異氰酸酯以及脂肪族二異氰酸酯中之任一者。作為芳香族二異氰酸酯，可列舉：1,5-萘二異氰酸酯、4,4'-二苯基甲烷二異氰酸酯(MDI)、4,4'-二苯基二甲基甲烷二異氰酸酯、四甲基二苯基甲烷二異氰酸酯、1,3-伸苯基二異氰酸酯、1,4-伸苯基二異氰酸酯、2-氯-1,4-苯基二異氰酸酯、2,4-甲苯二異氰酸酯、2,6-甲苯二異氰酸酯、苯二亞甲基二異氰酸酯、4,4'-二苯基醚二異氰酸酯、4,4'-二苯基亞碸二異氰酸酯、4,4'-二苯碸二異氰酸酯、4,4'-聯苯二異氰酸酯等。作為脂肪族二異氰酸酯，可列舉：丁烷-1,4-二異氰酸酯、六亞甲基二異氰酸酯、2,2,4-三甲基六亞甲基二異氰酸酯、2,4,4-三甲基六亞甲基二異氰酸酯、環己烷-1,4-二異氰酸酯、異佛爾酮二異氰酸酯、二環己基甲烷-4,4'-二異氰酸酯、1,3-雙(異氰酸基甲基)環己烷、甲基環己烷二異氰酸酯等。Any of aromatic diisocyanate and aliphatic diisocyanate may be used as diisocyanate for forming a polyurethane chain. Examples of the aromatic diisocyanate include: 1,5-naphthalene diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), 4,4'-diphenyldimethylmethane diisocyanate, tetramethyl Diphenylmethane diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2-chloro-1,4-phenylene diisocyanate, 2,4-toluene diisocyanate, 2, 6-toluene diisocyanate, xylylene diisocyanate, 4,4'-diphenyl ether diisocyanate, 4,4'-diphenylene diisocyanate, 4,4'-diphenylene diisocyanate, 4,4'-biphenyl diisocyanate, etc. Examples of the aliphatic diisocyanate include butane-1,4-diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethyl Hexamethylene diisocyanate, cyclohexane-1,4-diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis(isocyanatomethyl base) cyclohexane, methylcyclohexane diisocyanate, etc.

亦可使用異氰酸酯化合物之衍生物作為二異氰酸酯。作為異氰酸酯化合物之衍生物，可列舉：聚異氰酸酯之二聚物、異氰酸酯之三聚物(異氰脲酸酯)、聚合MDI、與三羥甲基丙烷之加成物、縮二脲改性體、脲基甲酸酯改性體、脲改性體等。可使用末端具有異氰酸酯基之胺基甲酸酯預聚物作為二異氰酸酯成分。Derivatives of isocyanate compounds can also be used as diisocyanates. Examples of derivatives of isocyanate compounds include dimers of polyisocyanates, trimers of isocyanates (isocyanurates), polymerized MDI, adducts with trimethylolpropane, and modified biurets. , allophanate modified body, urea modified body, etc. A urethane prepolymer having an isocyanate group at the terminal can be used as the diisocyanate component.

(利用胺基甲酸酯系鏈段向丙烯酸系聚合物鏈導入交聯結構) 藉由使用於聚胺基甲酸酯鏈之末端具有能夠與構成丙烯酸系聚合物鏈之單體成分共聚之官能基之化合物、或者於聚胺基甲酸酯鏈之末端具有能夠與丙烯酸系聚合物鏈中所含之羧基、羥基等反應之官能基之化合物，而能夠於丙烯酸系聚合物鏈導入由胺基甲酸酯系鏈段形成之交聯結構。就容易於丙烯酸系聚合物鏈均勻地導入交聯點並且丙烯酸系聚合物鏈與胺基甲酸酯系鏈段之相容性優異而言，故而較佳使用於聚胺基甲酸酯鏈之兩末端具有(甲基)丙烯醯基之二胺基甲酸酯(甲基)丙烯酸酯導入由胺基甲酸酯系鏈段形成之交聯結構。例如，藉由使構成丙烯酸系聚合物鏈之單體成分與二胺基甲酸酯(甲基)丙烯酸酯共聚，而能夠於丙烯酸系聚合物鏈導入由胺基甲酸酯系鏈段形成之交聯結構。(Introduction of a crosslinked structure to the acrylic polymer chain using a urethane-based segment) By using a compound having a functional group at the end of the polyurethane chain that can copolymerize with the monomer components constituting the acrylic polymer chain, or having a compound at the end of the polyurethane chain that can polymerize with the acrylic polymer Compounds with reactive functional groups such as carboxyl groups and hydroxyl groups contained in the polymer chain can introduce a cross-linked structure formed by urethane-based chain segments into the acrylic polymer chain. Since it is easy to uniformly introduce cross-linking points in the acrylic polymer chain and the compatibility between the acrylic polymer chain and the urethane segment is excellent, it is preferably used in the polyurethane chain. Diurethane (meth)acrylate having (meth)acryl groups at both ends introduces a crosslinked structure formed by urethane-based chain segments. For example, by copolymerizing the monomer components constituting the acrylic polymer chain with diurethane (meth)acrylate, it is possible to introduce a urethane-based segment into the acrylic polymer chain. Cross-linked structure.

於兩末端具有(甲基)丙烯醯基之二胺基甲酸酯(甲基)丙烯酸酯例如係藉由於聚胺基甲酸酯之聚合中除了二醇成分以外亦使用具有羥基之(甲基)丙烯酸化合物而獲得。就控制胺基甲酸酯系鏈段之鏈長(分子量)之觀點而言，較佳為以使異氰酸酯過量之方式使二醇與二異氰酸酯反應而合成異氰酸酯末端聚胺基甲酸酯，然後添加具有羥基之(甲基)丙烯酸化合物，使聚胺基甲酸酯之末端異氰酸酯基與(甲基)丙烯酸化合物之羥基反應。Diurethane (meth)acrylates having (meth)acryl groups at both ends are, for example, obtained by using (meth)acrylates having hydroxyl groups in addition to diol components in polyurethane polymerization. ) acrylic acid compounds. From the viewpoint of controlling the chain length (molecular weight) of the urethane-based segment, it is preferable to react a diol with a diisocyanate so that the isocyanate is in excess to synthesize an isocyanate-terminated polyurethane, and then add The (meth)acrylic compound reacts the terminal isocyanate group of the polyurethane with the hydroxyl group of the (meth)acrylic compound.

藉由以使聚異氰酸酯化合物過量之方式使多元醇與聚異氰酸酯化合物反應，而獲得於末端具有異氰酸酯基之聚胺基甲酸酯鏈。為了獲得異氰酸酯末端聚胺基甲酸酯，只要以使NCO/OH(當量比)較佳為1.1～2.0、更佳為1.15～1.5之方式使用二醇成分與二異氰酸酯成分即可。可於大致等量混合二醇成分與二異氰酸酯成分並使其反應後追加二異氰酸酯成分。A polyurethane chain having an isocyanate group at a terminal is obtained by reacting a polyol and a polyisocyanate compound so that the polyisocyanate compound is in excess. In order to obtain isocyanate-terminated polyurethane, it is sufficient to use a diol component and a diisocyanate component so that NCO/OH (equivalent ratio) becomes like this. Preferably it is 1.1-2.0, More preferably, it is 1.15-1.5. After mixing and reacting a diol component and a diisocyanate component in substantially equal amounts, a diisocyanate component can be added.

作為具有羥基之(甲基)丙烯酸化合物，可列舉：(甲基)丙烯酸羥基乙基酯、(甲基)丙烯酸羥基丙基酯、(甲基)丙烯酸羥基丁基酯、(甲基)丙烯酸羥基己基酯、羥甲基丙烯醯胺、羥乙基丙烯醯胺等。Examples of (meth)acrylic compounds having a hydroxyl group include: hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, hydroxy (meth)acrylate Hexyl ester, hydroxymethylacrylamide, hydroxyethylacrylamide, etc.

作為胺基甲酸酯(甲基)丙烯酸酯，可使用由荒川化學工業、新中村化學工業、東亞合成、共榮社化學、日本化藥、日本合成化學工業、根上工業、Daicel allnex等各公司銷售之市售品。胺基甲酸酯(甲基)丙烯酸酯之重量平均分子量較佳為4000～50000，更佳為4500～40000，進而較佳為5000～30000。Urethane (meth)acrylates manufactured by various companies such as Arakawa Chemical Industry, Shin-Nakamura Chemical Industry, Toagosei, Kyoeisha Chemical, Nippon Kayaku, Nippon Gosei Chemical Industry, Negami Industry, and Daicel allnex can be used. Commercially available items for sale. The weight average molecular weight of urethane (meth)acrylate becomes like this. Preferably it is 4,000-50,000, More preferably, it is 4,500-40,000, More preferably, it is 5,000-30,000.

胺基甲酸酯(甲基)丙烯酸酯之玻璃轉移溫度較佳為0℃以下，更佳為-10℃以下，進而較佳為-20℃以下。藉由使用低Tg之(甲基)丙烯酸胺基甲酯酯，而即便於利用胺基甲酸酯系鏈段導入交聯結構而提高基礎聚合物之凝集力之情形時，亦可獲得低溫接著力優異之黏著劑。胺基甲酸酯(甲基)丙烯酸酯之玻璃轉移溫度之下限並無特別限制，就獲得高溫保持力優異之黏著劑之觀點而言，較佳為-100℃以上，更佳為-90℃以上，進而較佳為-80℃以上。The glass transition temperature of the urethane (meth)acrylate is preferably at most 0°C, more preferably at most -10°C, further preferably at most -20°C. By using low Tg aminomethyl (meth)acrylate, low temperature adhesion can be obtained even when the cohesive force of the base polymer is improved by introducing a cross-linked structure with a urethane-based segment. Excellent adhesive. The lower limit of the glass transition temperature of urethane (meth)acrylate is not particularly limited, but it is preferably -100°C or higher, more preferably -90°C from the viewpoint of obtaining an adhesive having excellent high-temperature retention above, and more preferably above -80°C.

於使用胺基甲酸酯(甲基)丙烯酸酯於丙烯酸系聚合物鏈上導入由胺基甲酸酯系鏈段形成之交聯結構之情形時，基礎聚合物之胺基甲酸酯系鏈段之玻璃轉移溫度與胺基甲酸酯(甲基)丙烯酸酯之玻璃轉移溫度大致相等。When using urethane (meth)acrylate to introduce a cross-linked structure formed by urethane-based segments into the acrylic polymer chain, the urethane-based chain of the base polymer The glass transition temperature of the segment is about the same as that of the urethane (meth)acrylate.

＜基礎聚合物之製備＞ 於丙烯酸系聚合物鏈導入由胺基甲酸酯系鏈段形成之交聯結構之聚合物可利用各種公知之方法聚合。於使用胺基甲酸酯(甲基)丙烯酸酯作為胺基甲酸酯系鏈段之構成成分之情形時，只要將用於構成丙烯酸系聚合物鏈之單體成分與胺基甲酸酯(甲基)丙烯酸酯共聚即可。＜Preparation of base polymer＞ The polymer having a crosslinked structure formed of urethane segments introduced into the acrylic polymer chain can be polymerized by various known methods. In the case of using urethane (meth)acrylate as a constituent of the urethane-based chain segment, it is only necessary to combine the monomer components for constituting the acrylic polymer chain with the urethane ( Meth)acrylate copolymerization can be used.

胺基甲酸酯(甲基)丙烯酸酯之使用量，相對於用於構成丙烯酸系聚合物鏈之單體成分100重量份，較佳為3～30重量份，更佳為4～25重量份。藉由調整胺基甲酸酯(甲基)丙烯酸酯之使用量，而能夠製備胺基甲酸酯系鏈段之含量在上述範圍內之基礎聚合物。於胺基甲酸酯系鏈段之含量過小之情形時，有黏著片之接著保持力由於基礎聚合物之凝集性降低而降低之傾向。於胺基甲酸酯系鏈段之含量過大之情形時，有黏著片之黏性隨著基礎聚合物之凝集性之上升而減小，耐衝擊性降低之傾向。The amount of urethane (meth)acrylate used is preferably 3 to 30 parts by weight, more preferably 4 to 25 parts by weight, relative to 100 parts by weight of monomer components for constituting the acrylic polymer chain . By adjusting the usage-amount of a urethane (meth)acrylate, the base polymer whose content of a urethane system segment falls within the said range can be prepared. When the content of the urethane-based segment is too small, the adhesive holding force of the adhesive sheet tends to decrease due to the decrease in the cohesiveness of the base polymer. When the content of the urethane-based segment is too large, the viscosity of the adhesive sheet decreases as the cohesiveness of the base polymer increases, and the impact resistance tends to decrease.

作為基礎聚合物之聚合方法，較佳為光聚合。光聚合中，能夠於不使用溶劑之情形時製備聚合物，故而於形成黏著片時無需溶劑之乾燥除去，能夠均勻地形成厚度較大之黏著片。另外，光聚合中，聚合度之調整較為容易，藉由再次光照射能夠使聚合重新開始，因此適合於半硬化之黏著片之形成。As the polymerization method of the base polymer, photopolymerization is preferable. In photopolymerization, a polymer can be produced without using a solvent, so it is not necessary to dry and remove the solvent when forming an adhesive sheet, and an adhesive sheet with a large thickness can be uniformly formed. In addition, in photopolymerization, the adjustment of the degree of polymerization is relatively easy, and polymerization can be restarted by re-irradiating light, so it is suitable for the formation of semi-hardened adhesive sheets.

於基礎聚合物之製備中，可使全部量之構成丙烯酸系聚合物鏈之單體成分以及用於導入交聯結構之胺基甲酸酯(甲基)丙烯酸酯一次性進行反應，亦可藉由多階段進行聚合。作為以多階段進行聚合之方法，較佳為如下方法：將構成丙烯酸系聚合物鏈之單官能單體聚合，形成預聚物組合物(預聚合)，於預聚物組合物之漿料中添加二胺基甲酸酯(甲基)丙烯酸酯等多官能化合物，使預聚物組合物與多官能單體聚合(正式聚合)。預聚物組合物為含有低聚合度聚合物及未反應單體之部分聚合物。In the preparation of the base polymer, the entire amount of the monomer components constituting the acrylic polymer chain and the urethane (meth)acrylate used to introduce the crosslinked structure can be reacted at one time, or by Aggregation is performed in multiple stages. As a method of polymerizing in multiple stages, the method of polymerizing the monofunctional monomer constituting the acrylic polymer chain to form a prepolymer composition (prepolymerization) in the slurry of the prepolymer composition is preferable. A polyfunctional compound such as diurethane (meth)acrylate is added to polymerize the prepolymer composition and the polyfunctional monomer (main polymerization). The prepolymer composition is a partial polymer containing a polymer with a low degree of polymerization and unreacted monomers.

藉由進行丙烯酸系聚合物之構成成分之預聚合，而能夠於丙烯酸系聚合物鏈均勻地導入利用二胺基甲酸酯(甲基)丙烯酸酯等多官能化合物獲得之分支點(交聯點)。另外，藉由將低分子量聚合物或部分聚合物與未聚合單體成分之混合物(黏著劑組合物)塗佈於基材上，然後於基材上進行正式聚合，亦能夠形成黏著片。By pre-polymerizing the constituents of the acrylic polymer, it is possible to uniformly introduce branch points (crosslinking points) obtained by polyfunctional compounds such as diurethane (meth)acrylate into the acrylic polymer chain. ). In addition, an adhesive sheet can also be formed by coating a low molecular weight polymer or a mixture of a part of a polymer and an unpolymerized monomer component (adhesive composition) on a substrate, and then performing full-scale polymerization on the substrate.

預聚物組合物等低聚合度組合物為低黏度且塗佈性優異，因此，根據塗佈作為預聚物組合物與多官能化合物之混合物之黏著劑組合物後於基材上進行正式聚合之方法，能夠提高黏著片之生產性，並且能夠使黏著片之厚度均勻。另外，藉由調整正式聚合之聚合率，能夠形成階差吸收性優異之半硬化黏著片。Compositions with a low degree of polymerization such as prepolymer compositions have low viscosity and excellent applicability. Therefore, by coating an adhesive composition that is a mixture of a prepolymer composition and a multifunctional compound, the full-scale polymerization is performed on the substrate. According to the method, the productivity of the adhesive sheet can be improved, and the thickness of the adhesive sheet can be made uniform. In addition, by adjusting the polymerization rate of main polymerization, it is possible to form a semi-cured adhesive sheet excellent in step absorption.

[黏著片] 如上所述，藉由預聚合製備低聚合度預聚物組合物，將於預聚物組合物中添加多官能化合物等之黏著劑組合物以層狀塗佈於基材上，並進行基材上之黏著劑組合物之聚合(正式聚合)，藉此可獲得半硬化黏著片。[adhesive sheet] As mentioned above, a prepolymer composition with a low degree of polymerization is prepared by prepolymerization, and an adhesive composition in which a multifunctional compound or the like is added to the prepolymer composition is coated on a substrate in a layered form, and the substrate is Polymerization (formal polymerization) of the above adhesive composition, whereby a semi-hardened adhesive sheet can be obtained.

＜預聚合＞ 預聚物組合物例如可藉由將使構成丙烯酸系聚合物鏈之單體成分與聚合起始劑混合而獲得之組合物聚合來製備。預聚物形成用組合物可含有多官能化合物(多官能單體或多官能低聚物)。例如，可於預聚物形成用組合物中含有作為聚合物之原料之多官能化合物之一部分，並於將預聚物聚合後添加多官能化合物之剩餘部分而進行正式聚合。＜Prepolymerization＞ The prepolymer composition can be prepared, for example, by polymerizing a composition obtained by mixing monomer components constituting an acrylic polymer chain and a polymerization initiator. The composition for prepolymer formation may contain a polyfunctional compound (polyfunctional monomer or polyfunctional oligomer). For example, a part of the polyfunctional compound as a raw material of the polymer may be contained in the composition for forming a prepolymer, and the remaining part of the polyfunctional compound may be added after the prepolymer is polymerized to carry out main polymerization.

預聚物形成用組合物較佳為含有光聚合起始劑。作為光聚合起始劑，可列舉：安息香醚系光聚合起始劑、苯乙酮系光聚合起始劑、α-酮醇系光聚合起始劑、芳香族磺醯氯系光聚合起始劑、光活性肟系光聚合起始劑、安息香系光聚合起始劑、苯偶醯系光聚合起始劑、二苯甲酮系光聚合起始劑、縮酮系光聚合起始劑、噻噸酮系光聚合起始劑、醯基氧化膦系光聚合起始劑等。The composition for prepolymer formation preferably contains a photopolymerization initiator. Examples of photopolymerization initiators include: benzoin ether-based photopolymerization initiators, acetophenone-based photopolymerization initiators, α-ketol-based photopolymerization initiators, aromatic sulfonyl chloride-based photopolymerization initiators agent, photoactive oxime-based photopolymerization initiator, benzoin-based photopolymerization initiator, benzoyl-based photopolymerization initiator, benzophenone-based photopolymerization initiator, ketal-based photopolymerization initiator, Thioxanthone-based photopolymerization initiators, acylphosphine oxide-based photopolymerization initiators, and the like.

聚合時，以調整分子量等為目的，可使用鏈轉移劑、或阻聚劑(聚合延遲劑)等。作為鏈轉移劑，可列舉：α-硫代甘油、月桂基硫醇、縮水甘油基硫醇、巰基乙酸、2-巰基乙醇、硫代乙醇酸、硫代乙醇酸2-乙基己基酯、2,3-二巰基-1-丙醇等硫醇類、或α-甲基苯乙烯二聚物等。During polymerization, for the purpose of adjusting the molecular weight, etc., a chain transfer agent, a polymerization inhibitor (polymerization retarder), or the like can be used. Examples of the chain transfer agent include: α-thioglycerol, lauryl mercaptan, glycidyl mercaptan, thioglycolic acid, 2-mercaptoethanol, thioglycolic acid, 2-ethylhexyl thioglycolic acid, 2 , Thiols such as 3-dimercapto-1-propanol, or α-methylstyrene dimer, etc.

預聚物形成用組合物中，除了單體以及聚合起始劑以外，可視需要含有鏈轉移劑等。預聚合中所使用之聚合起始劑或鏈轉移劑並無特別限制，例如可使用上述光聚合起始劑或鏈轉移劑。In addition to a monomer and a polymerization initiator, the composition for prepolymer formation may contain a chain transfer agent etc. as needed. The polymerization initiator or chain transfer agent used in the prepolymerization is not particularly limited, for example, the above-mentioned photopolymerization initiator or chain transfer agent can be used.

預聚物之聚合率並無特別限制，就設為適合塗佈於基材上之黏度之觀點而言，較佳為3～50重量%，更佳為5～40重量%。預聚物之聚合率可根據調整光聚合起始劑之種類或使用量、UV光等活性光線之照射強度・照射時間等而調整至所期望之範圍內。The polymerization ratio of the prepolymer is not particularly limited, but is preferably 3 to 50% by weight, more preferably 5 to 40% by weight, from the viewpoint of setting a viscosity suitable for coating on a substrate. The polymerization rate of the prepolymer can be adjusted to a desired range by adjusting the type or amount of photopolymerization initiator, the irradiation intensity and irradiation time of active light such as UV light, etc.

＜黏著劑組合物之製備＞ 於上述預聚物組合物中，將胺基甲酸酯(甲基)丙烯酸酯、以及視需要之構成丙烯酸系聚合物鏈之單體成分之剩餘部分、聚合起始劑、鏈轉移劑、其他添加劑等混合而製備黏著劑組合物。黏著劑組合物較佳為具有適合塗佈於基材上之黏度(例如，0.5～20 Pa・s左右)。藉由調整預聚物之聚合率、胺基甲酸酯(甲基)丙烯酸酯之添加量、其他成分(例如低聚物)之組成、分子量、添加量等，能夠將黏著劑組合物之黏度調整至適當之範圍內。以調整黏度等為目的，可使用增黏性添加劑等。＜Preparation of Adhesive Composition＞ In the above-mentioned prepolymer composition, urethane (meth)acrylate, and optionally the remainder of the monomer components constituting the acrylic polymer chain, polymerization initiator, chain transfer agent, other Additives and the like are mixed to prepare an adhesive composition. The adhesive composition preferably has a viscosity suitable for coating on a substrate (for example, about 0.5-20 Pa·s). The viscosity of the adhesive composition can be adjusted by adjusting the polymerization rate of the prepolymer, the amount of urethane (meth)acrylate added, the composition, molecular weight, and amount of other components (such as oligomers) Adjust to an appropriate range. For the purpose of adjusting viscosity and the like, a thickening additive and the like may be used.

正式聚合中所使用之聚合起始劑或鏈轉移劑並無特別限制，例如可使用上述光聚合起始劑或鏈轉移劑。於預聚合時之聚合起始劑於預聚物組合物中不失活而殘留之情形時，可省略添加用於正式聚合之聚合起始劑。The polymerization initiator or chain transfer agent used in the main polymerization is not particularly limited, for example, the above-mentioned photopolymerization initiator or chain transfer agent can be used. When the polymerization initiator at the time of prepolymerization remains in the prepolymer composition without being deactivated, the addition of the polymerization initiator used for the main polymerization can be omitted.

(低聚物) 以調整黏著片之接著力、或調整黏度等為目的，黏著劑組合物可含有各種低聚物。作為低聚物，例如可使用重量平均分子量為1000～30000左右之低聚物。作為低聚物，就與丙烯酸系基礎聚合物之相容性優異而言，較佳為丙烯酸系低聚物。(Oligomer) The adhesive composition may contain various oligomers for the purpose of adjusting the adhesive force of the adhesive sheet, adjusting the viscosity, and the like. As an oligomer, the oligomer whose weight average molecular weight is about 1000-30000 can be used, for example. As the oligomer, an acrylic oligomer is preferred because it has excellent compatibility with the acrylic base polymer.

丙烯酸系低聚物含有(甲基)丙烯酸烷基酯作為主要構成單體成分。其中，較佳包含具有鏈狀烷基之(甲基)丙烯酸烷基酯((甲基)丙烯酸鏈狀烷基酯)、以及具有脂環式烷基之(甲基)丙烯酸烷基酯((甲基)丙烯酸脂環式烷基酯)之單體作為構成單體成分之丙烯酸系低聚物。(甲基)丙烯酸鏈狀烷基酯以及(甲基)丙烯酸脂環式烷基酯之具體例作為丙烯酸系聚合物鏈之構成單體如先前中例示所示。The acrylic oligomer contains an alkyl (meth)acrylate as a main constituent monomer component. Among them, alkyl (meth)acrylates (chain alkyl (meth)acrylates) with chain alkyl groups and alkyl (meth)acrylates ((meth)acrylates with alicyclic alkyl groups (( The monomer of aliphatic cycloalkyl meth)acrylate) is an acrylic oligomer constituting the monomer component. Specific examples of chain alkyl (meth)acrylates and alicyclic alkyl (meth)acrylates are exemplified above as monomers constituting the acrylic polymer chain.

丙烯酸系低聚物之玻璃轉移溫度較佳為20℃以上，更佳為30℃以上，進而較佳為40℃以上。藉由併用導入由胺基甲酸酯系鏈段形成之交聯結構之低Tg之基礎聚合物及高Tg之丙烯酸系低聚物，而有黏著片之接著保持力提高之傾向。丙烯酸系低聚物之玻璃轉移溫度之上限並無特別限制，一般而言為200℃以下，較佳為180℃以下，更佳為160℃以下。丙烯酸系低聚物之玻璃轉移溫度利用上述Fox式進行計算。The glass transition temperature of the acrylic oligomer is preferably at least 20°C, more preferably at least 30°C, and still more preferably at least 40°C. By using together a low Tg base polymer and a high Tg acrylic oligomer introduced with a crosslinked structure formed by a urethane-based segment, the adhesive holding force of the adhesive sheet tends to be improved. The upper limit of the glass transition temperature of the acrylic oligomer is not particularly limited, and is generally below 200°C, preferably below 180°C, more preferably below 160°C. The glass transition temperature of the acrylic oligomer was calculated using the above-mentioned Fox formula.

例示之(甲基)丙烯酸烷基酯之中，作為(甲基)丙烯酸鏈狀烷基酯，就玻璃轉移溫度較高、與基礎聚合物之相容性優異而言，較佳為甲基丙烯酸甲酯。作為(甲基)丙烯酸脂環式烷基酯，較佳為丙烯酸二環戊酯、甲基丙烯酸二環戊酯、丙烯酸環己酯以及甲基丙烯酸環己酯。即，丙烯酸系低聚物較佳為含有選自由丙烯酸二環戊酯、甲基丙烯酸二環戊酯、丙烯酸環己酯以及甲基丙烯酸環己酯所組成之群中之一種以上及甲基丙烯酸甲酯作為構成單體成分。Among the exemplified alkyl (meth)acrylates, methacrylic acid is preferred as the chain alkyl (meth)acrylate in terms of its high glass transition temperature and excellent compatibility with the base polymer. methyl ester. As the alicyclic alkyl (meth)acrylate, dicyclopentyl acrylate, dicyclopentyl methacrylate, cyclohexyl acrylate, and cyclohexyl methacrylate are preferable. That is, the acrylic oligomer preferably contains at least one selected from the group consisting of dicyclopentanyl acrylate, dicyclopentanyl methacrylate, cyclohexyl acrylate, and cyclohexyl methacrylate and methacrylic acid. Methyl ester is used as a constituent monomer component.

(甲基)丙烯酸脂環式烷基酯之量相對於構成丙烯酸系低聚物之單體成分總量，較佳為10～90重量%，更佳為20～80重量%，進而較佳為30～70重量%。(甲基)丙烯酸鏈狀烷基酯之量相對於構成丙烯酸系低聚物之單體成分總量，較佳為10～90重量%，更佳為20～80重量%，進而較佳為30～70重量%。The amount of alicyclic alkyl (meth)acrylate is preferably 10 to 90% by weight, more preferably 20 to 80% by weight, and still more preferably 30 to 70% by weight. The amount of chain alkyl (meth)acrylate is preferably 10 to 90% by weight, more preferably 20 to 80% by weight, and still more preferably 30% by weight relative to the total amount of monomer components constituting the acrylic oligomer. ~70% by weight.

丙烯酸系低聚物之重量平均分子量較佳為1000～30000，更佳為1500～10000，進而較佳為2000～8000。藉由使用具有該範圍之分子量之丙烯酸系低聚物，而有黏著劑之接著力、或接著保持力提高之傾向。The weight average molecular weight of an acrylic oligomer becomes like this. Preferably it is 1,000-30,000, More preferably, it is 1,500-10,000, More preferably, it is 2,000-8,000. The use of an acrylic oligomer having a molecular weight within this range tends to improve the adhesion or adhesion retention of the adhesive.

丙烯酸系低聚物可藉由將上述單體成分用各種聚合方法聚合而獲得。於丙烯酸系低聚物聚合時，可使用各種聚合起始劑。另外，以調整分子量為目的，可使用鏈轉移劑。The acrylic oligomer can be obtained by polymerizing the above-mentioned monomer components by various polymerization methods. When the acrylic oligomer is polymerized, various polymerization initiators can be used. In addition, a chain transfer agent can be used for the purpose of adjusting the molecular weight.

於黏著劑組合物中含有丙烯酸系低聚物等低聚物成分之情形時，其含量相對於上述基礎聚合物100重量份，較佳為0.5～20重量份，更佳為1～15重量份，進而較佳為2～10重量份。黏著劑組合物中之低聚物之含量在上述範圍內之情形時，有高溫下之接著性以及高溫保持力提高之傾向。When the adhesive composition contains oligomer components such as acrylic oligomers, the content thereof is preferably 0.5 to 20 parts by weight, more preferably 1 to 15 parts by weight, based on 100 parts by weight of the above-mentioned base polymer. , and more preferably 2 to 10 parts by weight. When the content of the oligomer in the adhesive composition is within the above range, the adhesiveness at high temperature and the high temperature retention tend to be improved.

(矽烷偶合劑) 以調整接著力為目的，可於黏著劑組合物中添加矽烷偶合劑。於黏著劑組合物中添加矽烷偶合劑之情形時，其添加量相對於基礎聚合物100重量份通常為0.01～5.0重量份左右，較佳為0.03～2.0重量份左右。(silane coupling agent) For the purpose of adjusting the adhesive force, a silane coupling agent can be added to the adhesive composition. When adding a silane coupling agent to an adhesive composition, the addition amount is normally about 0.01-5.0 weight part with respect to 100 weight part of base polymers, Preferably it is about 0.03-2.0 weight part.

(交聯劑) 基礎聚合物可視需要具有除上述多官能化合物以外之交聯結構。藉由於黏著劑組合物中含有交聯劑，而能夠於基礎聚合物中導入交聯結構。作為交聯劑，可列舉與聚合物中所含之羥基、或羧基等官能基反應之化合物。作為交聯劑之具體例，可列舉：異氰酸酯系交聯劑、環氧系交聯劑、㗁

唑啉系交聯劑、氮丙啶系交聯劑、碳二醯亞胺系交聯劑、金屬螯合物系交聯劑等。(Crosslinking Agent) The base polymer may have a crosslinked structure other than the above-mentioned polyfunctional compound as needed. By containing a crosslinking agent in the adhesive composition, a crosslinked structure can be introduced into the base polymer. As a crosslinking agent, the compound which reacts with the functional group, such as a hydroxyl group and a carboxyl group contained in a polymer, is mentioned. Specific examples of the cross-linking agent include: isocyanate-based cross-linking agents, epoxy-based cross-linking agents,

Azoline-based cross-linking agents, aziridine-based cross-linking agents, carbodiimide-based cross-linking agents, metal chelate-based cross-linking agents, and the like.

若由除胺基甲酸酯系鏈段以外之物質形成之交聯結構之導入量增加，則有時黏性降低、耐衝擊性降低。因此，交聯劑之使用量相對於基礎聚合物100重量份，較佳為3重量份以下，更佳為2重量份以下，進而較佳為1重量份以下。When the introduction amount of the crosslinked structure formed by substances other than the urethane-based segment increases, the viscosity may decrease and the impact resistance may decrease. Therefore, the usage-amount of a crosslinking agent is preferably 3 parts by weight or less, more preferably 2 parts by weight or less, and still more preferably 1 part by weight or less, based on 100 parts by weight of the base polymer.

(其他添加劑) 除上述例示之各成分以外，黏著劑組合物可含有增黏劑、塑化劑、軟化劑、劣化抑制劑、填充劑、著色劑、紫外線吸收劑、抗氧化劑、界面活性劑、防靜電劑等添加劑。(other additives) The adhesive composition may contain tackifiers, plasticizers, softeners, deterioration inhibitors, fillers, colorants, ultraviolet absorbers, antioxidants, surfactants, antistatic agents, etc. additive.

＜黏著劑組合物之塗佈以及正式聚合＞ 藉由於基材上以層狀塗佈黏著劑組合物，然後照射活性光線而進行光硬化。進行光硬化時，較佳為於塗佈層之表面設置覆蓋片，於將黏著劑組合物夾在兩張片材之間之狀態下照射活性光線，從而防止由氧氣引起之聚合抑制。＜Coating and full-scale polymerization of adhesive composition＞ Photohardening is performed by coating the adhesive composition in a layer on the base material and then irradiating active light. When photocuring is performed, it is preferable to provide a cover sheet on the surface of the coating layer, and to irradiate active light with the adhesive composition sandwiched between the two sheets, thereby preventing polymerization inhibition by oxygen.

作為用於形成黏著片之基材以及覆蓋片，可使用任意適當之基材。基材以及覆蓋片可為於與黏著片之接觸面上具有脫模層之離型膜。Any appropriate base material can be used as the base material and the cover sheet for forming the adhesive sheet. The substrate and the cover sheet may be a release film having a release layer on the contact surface with the adhesive sheet.

作為離型膜之膜基材，可使用包含各種樹脂材料之膜。作為樹脂材料，可列舉：聚對苯二甲酸乙二酯、聚萘二甲酸乙二酯等聚酯系樹脂、乙酸酯系樹脂、聚醚碸系樹脂、聚碳酸酯系樹脂、聚醯胺系樹脂、聚醯亞胺系樹脂、聚烯烴系樹脂、(甲基)丙烯酸系樹脂、聚氯乙烯系樹脂、聚偏二氯乙烯系樹脂、聚苯乙烯系樹脂、聚乙烯醇系樹脂、聚芳酯系樹脂、聚苯硫醚系樹脂等。該等之中，特別較佳為聚對苯二甲酸乙二酯等聚酯系樹脂。膜基材之厚度較佳為10～200 μm，更佳為25～150 μm。作為脫模層之材料，可列舉：聚矽氧系脫模劑、氟系脫模劑、長鏈烷基系脫模劑、脂肪醯胺系脫模劑等。脫模層之厚度一般而言為10～2000 nm左右。As the film base material of the release film, films made of various resin materials can be used. Examples of the resin material include polyester-based resins such as polyethylene terephthalate and polyethylene naphthalate, acetate-based resins, polyether-based resins, polycarbonate-based resins, and polyamide resins. resin, polyimide resin, polyolefin resin, (meth)acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, polystyrene resin, polyvinyl alcohol resin, poly Aryl ester resins, polyphenylene sulfide resins, etc. Among them, polyester-based resins such as polyethylene terephthalate are particularly preferable. The thickness of the film substrate is preferably from 10 to 200 μm, more preferably from 25 to 150 μm. Examples of the material for the release layer include silicone-based release agents, fluorine-based release agents, long-chain alkyl-based release agents, and aliphatic amide-based release agents. The thickness of the release layer is generally about 10 to 2000 nm.

作為於基材上塗佈黏著劑組合物之方法，可使用輥塗法、接觸輥式塗佈法、凹版塗佈法、反向塗佈法、輥刷法、噴塗法、浸漬輥塗法、刮棒塗佈法、刮刀塗佈法、氣刀塗佈法、幕簾塗佈法、唇模塗佈法、模嘴塗佈機等各種方法。As the method of coating the adhesive composition on the base material, roll coating method, touch roll coating method, gravure coating method, reverse coating method, roll brush method, spray coating method, dip roll coating method, Bar coating method, knife coating method, air knife coating method, curtain coating method, lip coating method, die coating machine and other methods.

藉由對於基材上以層狀塗佈後之黏著劑組合物照射活性光線，而進行正式聚合。於正式聚合中，預聚物組合物中之未反應之單體成分與胺基甲酸酯(甲基)丙烯酸酯發生反應，獲得於丙烯酸系聚合物鏈導入由胺基甲酸酯系鏈段形成之交聯結構之基礎聚合物。藉由調整正式聚合中之聚合率而使聚合性化合物之一部分由於未反應而殘留，藉此可獲得半硬化黏著片。Full-scale polymerization is performed by irradiating active light rays to the adhesive composition coated in a layer on the substrate. In the formal polymerization, the unreacted monomer components in the prepolymer composition react with the urethane (meth)acrylate to obtain a urethane-based chain segment introduced into the acrylic polymer chain The base polymer that forms the cross-linked structure. A semi-hardened adhesive sheet can be obtained by adjusting the polymerization rate in main polymerization so that a part of the polymerizable compound remains unreacted.

活性光線只要根據單體或胺基甲酸酯(甲基)丙烯酸酯等聚合性成分之種類、或光聚合起始劑之種類等選擇即可，一般而言使用紫外線/或短波長之可見光。照射光之累積光量較佳為100～5000 mJ/cm² 左右。作為用於光照射之光源，只要能夠照射出黏著劑組合物中所含之光聚合起始劑具有靈敏度之波長範圍之光之光源則無特別限制，較佳使用LED光源、高壓水銀燈、超高壓水銀燈、金屬鹵化物燈、氙氣燈等。於達到特定聚合率後，停止光照射，藉此能夠將聚合率調整至特定之範圍內。如上所述，半硬化黏著片之聚合率較佳為90%～98%。The active light may be selected according to the type of polymerizable components such as monomers or urethane (meth)acrylates, or the type of photopolymerization initiator, etc. Generally, ultraviolet rays and/or short-wavelength visible light are used. The cumulative light intensity of the irradiation light is preferably about 100 to 5000 mJ/cm ² . As the light source for light irradiation, there is no particular limitation as long as it can irradiate light in the wavelength range to which the photopolymerization initiator contained in the adhesive composition is sensitive. LED light sources, high-pressure mercury lamps, ultra-high pressure Mercury lamps, metal halide lamps, xenon lamps, etc. After reaching a specific polymerization rate, the light irradiation can be stopped, whereby the polymerization rate can be adjusted within a specific range. As mentioned above, the polymerization rate of the semi-hardened adhesive sheet is preferably 90% to 98%.

藉由於半硬化黏著片5之表面貼合離型膜1、2，可獲得如圖1所示於兩面暫時附著有離型膜之黏著片。可將於形成黏著片時作為基材或覆蓋片使用之離型膜直接用作離型膜1、2。By attaching the release films 1 and 2 to the surface of the semi-cured adhesive sheet 5, an adhesive sheet with release films temporarily attached to both sides as shown in FIG. 1 can be obtained. The release film that will be used as a base material or a cover sheet when forming an adhesive sheet can be directly used as the release film 1, 2.

於黏著片5之兩面設置有離型膜1、2之情形時，一個離型膜1之厚度與另一個離型膜2之厚度可相同，亦可不同。自黏著片5剝離暫時附著於一個面之離型膜時之剝離力與自黏著片5剝離暫時附著於另一個面之離型膜時之剝離力可相同亦可不同。於兩者之剝離力不同之情形時，將剝離力相對較小之離型膜2(輕剝離膜)自黏著片5先剝離後進行與第一被接著體之貼合，再將剝離力相對較大之離型膜1(重剝離膜)剝離，進行與第二被接著體之貼合，此種情形時之作業性優異。When release films 1 and 2 are provided on both sides of the adhesive sheet 5, the thickness of one release film 1 and the thickness of the other release film 2 may be the same or different. The peeling force when peeling off the release film temporarily attached to one side from the adhesive sheet 5 and the peeling force when peeling off the release film temporarily attached to the other side from the adhesive sheet 5 may be the same or different. When the peeling force of the two is different, peel off the release film 2 (light peeling film) with a relatively small peeling force from the adhesive sheet 5 first, then attach it to the first adherend, and then compare the peeling force The larger release film 1 (heavy release film) is peeled off and bonded to the second adherend. In this case, the workability is excellent.

[圖像顯示裝置] 本發明之黏著片能夠用於各種透明構件、或不透明構件之貼合。被接著體之種類並無特別特別限制，可列舉各種樹脂材料、玻璃、金屬等。本發明之黏著片由於透明性較高，因此適合於圖像顯示裝置等光學構件之貼合。特別是本發明之黏著片由於階差吸收性、或耐衝擊性優異，因此較佳用於前面透明板或觸控面板等透明構件向圖像顯示裝置之視認側表面之貼合。[Image display device] The adhesive sheet of the present invention can be used for bonding various transparent members or opaque members. The type of the adherend is not particularly limited, and examples include various resin materials, glass, metal, and the like. Since the adhesive sheet of the present invention has high transparency, it is suitable for lamination of optical components such as image display devices. In particular, the adhesive sheet of the present invention is preferably used for laminating transparent members such as front transparent plates or touch panels to the viewing side surface of an image display device due to its excellent step absorption or impact resistance.

圖2係表示於圖像顯示面板10之視認側表面經由黏著片5貼合前面透明板7之圖像顯示裝置之積層構成例的剖視圖。圖像顯示面板10具有於液晶單元或有機EL單元等圖像顯示單元6之視認側表面經由黏著片4貼合之偏光板3。前面透明板7於透明之平板71之一個面之周緣設置有印刷層76。透明板71例如使用丙烯酸系樹脂或聚碳酸酯系樹脂等透明樹脂板、或者玻璃板等。透明板71可具有觸控面板功能。作為觸控面板，使用電阻膜方式、靜電電容方式、光學方式、超音波方式等任意方式之觸控面板。2 is a cross-sectional view showing an example of a laminated structure of an image display device in which a front transparent plate 7 is bonded to the viewing side surface of an image display panel 10 via an adhesive sheet 5 . The image display panel 10 has a polarizing plate 3 bonded to the viewing side surface of an image display unit 6 such as a liquid crystal unit or an organic EL unit via an adhesive sheet 4 . The front transparent plate 7 is provided with a printing layer 76 on the periphery of one surface of the transparent flat plate 71 . For the transparent plate 71 , for example, a transparent resin plate such as acrylic resin or polycarbonate resin, or a glass plate is used. The transparent board 71 may have a touch panel function. As the touch panel, a touch panel of any type such as a resistive film type, a capacitive type, an optical type, or an ultrasonic type is used.

設置於圖像顯示面板10之表面之偏光板3與前面透明板7之印刷層76形成面經由黏著片5進行貼合。貼合之順序並無特別限制，可先進行黏著片5向圖像顯示面板10之貼合，亦可先進行黏著片5向前面透明板7之貼合。另外，亦可同時進行兩者之貼合。就貼合之作業性等觀點而言，較佳為將一個離型膜(輕剝離膜)2剝離，然後使露出之黏著片5之表面貼合於圖像顯示面板10，然後將另一個離型膜1(重剝離膜)剝離，使露出之黏著片之表面貼合於前面透明板7。The polarizing plate 3 provided on the surface of the image display panel 10 is bonded to the surface on which the printed layer 76 of the front transparent plate 7 is formed via the adhesive sheet 5 . The order of bonding is not particularly limited, and the bonding of the adhesive sheet 5 to the image display panel 10 can be carried out first, or the bonding of the adhesive sheet 5 to the front transparent plate 7 can be carried out first. In addition, the lamination of the two can also be carried out at the same time. From the standpoint of lamination workability, etc., it is preferable to peel off one release film (light release film) 2, then attach the surface of the exposed adhesive sheet 5 to the image display panel 10, and then peel off the other release film. The molded film 1 (heavy release film) is peeled off, so that the surface of the exposed adhesive sheet is attached to the front transparent plate 7.

於黏著片5與前面透明板7貼合後，較佳進行用於除去黏著片5與前面透明板7之平板71部分之間之界面、或印刷層76等非平坦部附近之氣泡之脫泡。作為脫泡方法，可採用加熱、加壓、減壓等適當之方法。例如，較佳為一面於減壓・加熱下抑制氣泡之混入一面進行貼合，然後，以抑制延遲起泡等為目的，藉由高壓釜處理等於加熱之同時進行加壓。於藉由加熱進行脫泡之情形時，加熱溫度一般而言為40～150℃左右。於進行加壓之情形時，壓力通常為0.05 MPa～2 MPa左右。After bonding the adhesive sheet 5 and the front transparent plate 7, it is preferable to perform defoaming for removing the interface between the adhesive sheet 5 and the flat plate 71 of the front transparent plate 7, or near the non-flat portion such as the printed layer 76. . As the defoaming method, appropriate methods such as heating, pressurization, and decompression can be employed. For example, it is preferable to bond while suppressing the mixing of air bubbles under reduced pressure and heating, and then, for the purpose of suppressing delayed foaming, etc., to pressurize while heating by autoclave treatment. In the case of defoaming by heating, the heating temperature is generally about 40 to 150°C. When pressurizing, the pressure is usually about 0.05 MPa to 2 MPa.

本發明之黏著片之半硬化狀態下之剪切儲存彈性模數為0.15 MPa以下，因此，容易追隨印刷層76等之階差形狀，因此，能夠抑制空隙之產生。The shear storage elastic modulus of the adhesive sheet of the present invention in a semi-cured state is 0.15 MPa or less, so it is easy to follow the step shape of the printed layer 76 and the like, and therefore, generation of voids can be suppressed.

使半硬化黏著片與前面透明板等被接著體貼合，然後進行黏著片之光硬化(後硬化)。聚合率藉由後硬化而上升，隨之，黏著片之儲存彈性模數增大，黏著片5與前面透明構件70之接著可靠性提高。後硬化後之黏著片之聚合率較佳為99%以上。The semi-cured adhesive sheet is attached to the substrate such as the front transparent plate, and then the adhesive sheet is photocured (post-cured). The polymerization rate is increased by post-hardening, and accordingly, the storage modulus of the adhesive sheet is increased, and the bonding reliability between the adhesive sheet 5 and the front transparent member 70 is improved. The polymerization rate of the post-hardened adhesive sheet is preferably above 99%.

於殼體9與前面透明板7之間存在間隙90之情形時，較佳為將樹脂材料等填充於間隙90而進行密封。如上所述，後硬化後之黏著片之剪切儲存彈性模數較大，因此，於較寬之溫度範圍內之接著可靠性優異。因此，即便於由於利用樹脂材料等進行密封時之溫度變化而於黏著片之貼合界面產生應力變形之情形時，亦能夠抑制貼合界面處之剝離。另外，後硬化後之黏著片由於玻璃轉移溫度較低並且tanδ之峰頂值大，因此，於較寬之溫度範圍內耐衝擊性優異，不容易發生由落下等衝擊引起之剝離。When there is a gap 90 between the housing 9 and the front transparent plate 7, it is preferable to fill the gap 90 with a resin material or the like and seal it. As described above, the post-cured adhesive sheet has a large shear storage elastic modulus, and therefore has excellent adhesion reliability over a wide temperature range. Therefore, even when stress deformation occurs at the bonding interface of the adhesive sheet due to a temperature change during sealing with a resin material or the like, peeling at the bonding interface can be suppressed. In addition, the post-cured adhesive sheet has a low glass transition temperature and a large peak value of tanδ, so it has excellent impact resistance in a wide temperature range and is less prone to peeling due to impact such as dropping.

如上所述，於黏著片為含有未反應光聚合性化合物之半硬化狀態之情形時，剪切儲存彈性模數較小，階差吸收性優異。因此，較佳用於向具有印刷階差之前面透明板或觸控面板等圖像顯示面板表面之貼合。As described above, when the adhesive sheet is in a semi-cured state containing an unreacted photopolymerizable compound, the shear storage elastic modulus is small and the step absorption property is excellent. Therefore, it is preferably used for bonding to the surface of an image display panel such as a front transparent plate having a printing level difference or a touch panel.

以使用半硬化黏著片而與具有由印刷層引起之印刷階差之前面透明板貼合後進行後硬化之方法為中心進行說明，但於不要求階差吸收性之情形時，可將完全硬化後之黏著片貼合於被接著體。例如，將黏著劑組合物以層狀塗佈於基材上，然後以使聚合率為99%以上之方式進行正式聚合，藉此可獲得黏著劑完全硬化後之黏著片。於使用完全硬化後之黏著片之情形時，亦與使用半硬化黏著片進行貼合後進行後硬化之情形同樣，不容易發生由應力變形或由落下等衝擊引起之剝離，能夠實現可靠性優異之接著。The explanation will focus on the method of using a semi-hardened adhesive sheet and laminating it with a front transparent plate with a printing level difference caused by the printed layer, and then post-curing. However, in the case where the absorption of the step is not required, it can be fully cured. The following adhesive sheet is attached to the adherend. For example, the adhesive composition is coated on the substrate in a layered form, and then the full-scale polymerization is carried out so that the polymerization rate is 99% or more, thereby obtaining an adhesive sheet after the adhesive is completely hardened. In the case of using a fully hardened adhesive sheet, similar to the case of using a semi-hardened adhesive sheet for lamination and then post-curing, it is less prone to peeling due to stress deformation or impact by dropping, and can achieve excellent reliability. Then follow.

[附黏著片之光學膜] 對於本發明之黏著片，除了如圖1所示於兩面暫時附著有離型膜之形態以外，亦可用作使黏著片固定於光學膜等之附黏著劑之膜。例如，於圖3所示之形態中，於黏著片5之一個面暫時附著有離型膜1，於黏著片5之另一個面固定有偏光板3。於圖4所示之形態中，於偏光板3上進而設置有黏著片4，並於其上暫時附著有離型膜2。[Optical film with adhesive sheet] The adhesive sheet of the present invention can also be used as a film for attaching an adhesive to fix the adhesive sheet to an optical film or the like in addition to the form in which a release film is temporarily attached to both sides as shown in FIG. 1 . For example, in the form shown in FIG. 3 , the release film 1 is temporarily attached to one surface of the adhesive sheet 5 , and the polarizing plate 3 is fixed to the other surface of the adhesive sheet 5 . In the form shown in FIG. 4 , an adhesive sheet 4 is further provided on the polarizing plate 3 , and a release film 2 is temporarily attached thereto.

如此，於黏著片上預先貼合有偏光板等光學膜之形態中，可將暫時附著於黏著片5之表面之離型膜1剝離，進行與前面透明構件之貼合，然後視需要進行黏著片5之後硬化。 實施例In this way, in the form where an optical film such as a polarizing plate is pasted on the adhesive sheet in advance, the release film 1 temporarily attached to the surface of the adhesive sheet 5 can be peeled off, and the front transparent member can be attached, and then the adhesive sheet can be bonded if necessary. 5 after hardening. Example

以下列舉實施例以及比較例對本發明更詳細地進行說明，但本發明不限於該等實施例。Examples and comparative examples are given below to describe the present invention in more detail, but the present invention is not limited to these examples.

[丙烯酸低聚物之製作] 將甲基丙烯酸二環戊酯(DCPMA)60重量份、甲基丙烯酸甲酯(MMA)40重量份、作為鏈轉移劑之α-硫代甘油3.5重量份以及作為聚合溶劑之甲苯100重量份混合，於氮氣氣氛下，於70℃下攪拌1小時。接著，投入作為熱聚合起始劑之2,2'-偶氮二異丁腈(AIBN)0.2重量份，於70℃下反應2小時，然後升溫至80℃反應2小時。然後，將反應液加熱至130℃，乾燥除去甲苯、鏈轉移劑以及未反應單體，獲得固形狀丙烯酸低聚物。丙烯酸低聚物之重量平均分子量為5100。[Production of Acrylic Oligomer] Mix 60 parts by weight of dicyclopentanyl methacrylate (DCPMA), 40 parts by weight of methyl methacrylate (MMA), 3.5 parts by weight of α-thioglycerol as a chain transfer agent, and 100 parts by weight of toluene as a polymerization solvent , stirred at 70° C. for 1 hour under a nitrogen atmosphere. Next, 0.2 parts by weight of 2,2'-azobisisobutyronitrile (AIBN) was added as a thermal polymerization initiator, reacted at 70° C. for 2 hours, and then heated up to 80° C. for 2 hours. Then, the reaction solution was heated to 130° C., and the toluene, chain transfer agent and unreacted monomers were removed by drying to obtain a solid acrylic oligomer. The weight average molecular weight of the acrylic oligomer was 5100.

[實施例1] (預聚物之聚合) 調配丙烯酸丁酯(BA)52.8重量份、丙烯酸環己酯(CHA)10.9重量份、N-乙烯基-2-吡咯烷酮(NVP)9.7重量份、丙烯酸4-羥基丁酯(4HBA)14.8重量份及丙烯酸異硬脂酯(ISTA)11.8重量份、以及光聚合起始劑(BASF製造之「Irgacure184」：0.035重量份及BASF製造之「Irgacure651」：0.035重量份作為預聚物形成用單體成分，然後照射紫外線進行聚合以使黏度(BH黏度計No.5轉子，10 rpm，測定溫度30℃)達到約20 Pa・s，從而獲得預聚物組合物(聚合率：約9%)。[Example 1] (polymerization of prepolymer) Prepare 52.8 parts by weight of butyl acrylate (BA), 10.9 parts by weight of cyclohexyl acrylate (CHA), 9.7 parts by weight of N-vinyl-2-pyrrolidone (NVP), 14.8 parts by weight of 4-hydroxybutyl acrylate (4HBA) and 11.8 parts by weight of isostearyl acrylate (ISTA), and photopolymerization initiators ("Irgacure 184" manufactured by BASF: 0.035 parts by weight and "Irgacure 651" manufactured by BASF: 0.035 parts by weight were used as monomer components for prepolymer formation, Afterwards, ultraviolet rays were irradiated to perform polymerization so that the viscosity (BH viscometer No. 5 rotor, 10 rpm, measurement temperature 30°C) became about 20 Pa·s, thereby obtaining a prepolymer composition (polymerization rate: about 9%).

(光硬化性黏著劑組合物之製備) 於上述預聚物組合物中，添加作為胺基甲酸酯(甲基)丙烯酸酯之末端丙烯酸改性聚醚胺基甲酸酯(日本合成化學工業製造之「UV-3300B」)：7重量份、及末端丙烯酸改性聚酯胺基甲酸酯(日本合成化學工業製造之「UV-3010B」)：3重量份、上述丙烯酸低聚物：5重量份、作為光聚合起始劑之Irgacure184：0.05重量份及Irgacure651：0.57重量份、作為鏈轉移劑之α-甲基苯乙烯二聚物(日油製造之「Nofmer MSD」)：0.1重量份、以及作為矽烷偶合劑之信越化學製造之「KBM403」)：0.3重量份，然後將該等均勻地混合，從而製備黏著劑組合物。(Preparation of photocurable adhesive composition) Add terminal acrylic-modified polyether urethane as urethane (meth)acrylate to the above prepolymer composition ("UV-3300B" manufactured by Nippon Synthetic Chemical Industry): 7 wt. Parts, and terminal acrylic modified polyester urethane ("UV-3010B" manufactured by Nippon Synthetic Chemical Industry): 3 parts by weight, the above-mentioned acrylic oligomer: 5 parts by weight, Irgacure 184 as a photopolymerization initiator : 0.05 parts by weight and Irgacure651: 0.57 parts by weight, α-methylstyrene dimer (Nofmer MSD manufactured by NOF) as a chain transfer agent: 0.1 parts by weight, and Shin-Etsu Chemical as a silane coupling agent "KBM403"): 0.3 parts by weight, and these were uniformly mixed to prepare an adhesive composition.

(黏著片之製作) 以於表面設置有聚矽氧系脫模層之厚度75 μm之聚對苯二甲酸乙二酯(PET)膜(三菱化學製造之「Diafoil MRF75」)作為基材(兼重剝離膜)，於基材上以使厚度為150 μm之方式塗佈上述光硬化性黏著劑組合物而形成塗佈層。於該塗佈層上貼合單面進行聚矽氧剝離處理之厚度75 μm之PET膜(三菱化學製造之「Diafoil MRE75」)作為覆蓋片(兼輕剝離膜)。利用以使燈正下方之照射面之照射強度以5 mW/cm² 之方式進行位置調節之黑光燈，自覆蓋片側對該積層體照射130秒紫外線而進行光硬化，獲得厚度150 μm、聚合率94%之黏著片。(Preparation of adhesive sheet) A polyethylene terephthalate (PET) film ("Diafoil MRF75" manufactured by Mitsubishi Chemical) with a thickness of 75 μm provided with a polysiloxane-based release layer on the surface was used as the base material (Kanhe peeling film), and coated the above-mentioned photocurable adhesive composition on the base material so that the thickness may become 150 micrometers, and the coating layer was formed. A 75 μm-thick PET film (“Diafoil MRE75” manufactured by Mitsubishi Chemical Co., Ltd.) was bonded on the coating layer as a cover sheet (also a light-weight release film). Using a black light lamp whose position is adjusted so that the irradiation intensity of the irradiation surface directly under the lamp is 5 mW/cm ² , the laminate is irradiated with ultraviolet rays for 130 seconds from the cover sheet side to perform photohardening, and obtain a thickness of 150 μm and a polymerization rate 94% of adhesive sheets.

[實施例2～7、比較例1～10] 將預聚物之聚合中之投入單體組成、以及黏著劑組合物中添加之多官能化合物(丙烯酸胺基甲酸酯及/或多官能丙烯酸酯)、丙烯酸低聚物、光聚合起始劑、以及鏈轉移劑之種類以及添加量變更為如表1-1以及表1-2所示。除此以外以與實施例1同樣之方式製備光硬化性黏著劑組合物，進行於基材上之塗佈、光硬化，從而獲得黏著片。於實施例4、比較例4以及比較例5中，使用與實施例3相同之黏著劑組合物，改變紫外線之照射時間，藉此獲得具有表1-1所示之聚合率之黏著片。[Examples 2-7, Comparative Examples 1-10] Polymerization of the prepolymer into the monomer composition, and the multifunctional compound (acrylic urethane and/or multifunctional acrylate), acrylic oligomer, photopolymerization initiator added to the adhesive composition , and the type and amount of chain transfer agent were changed as shown in Table 1-1 and Table 1-2. Except for this, the photocurable adhesive composition was prepared in the same manner as in Example 1, and the coating on the base material and photocuring were performed, and the adhesive sheet was obtained. In Example 4, Comparative Example 4, and Comparative Example 5, the same adhesive composition as in Example 3 was used, and the irradiation time of ultraviolet rays was changed to obtain an adhesive sheet having the polymerization rate shown in Table 1-1.

[評價] ＜重量平均分子量＞ 丙烯酸低聚物以及胺基甲酸酯(甲基)丙烯酸酯之重量平均分子量(Mw)利用東曹製造之GPC(凝膠滲透色譜)裝置(產品名「HLC-8120GPC」)進行測定。測定樣品使用利用0.45 μm之膜過濾器將基礎聚合物溶解於四氫呋喃製成0.1重量%之溶液後之物質過濾後之濾液。GPC之測定條件如下所述。 (測定條件) 管柱：東曹公司製造，G7000HXL+GMHXL+GMHXL 管柱尺寸：各7.8 mm

×30 cm(合計管柱長度：90 cm) 管柱溫度：40℃・流量：0.8 mL/min 注入量：100 μL 溶離液：四氫呋喃 檢測器：示差折射計(RI) 標準試樣：聚苯乙烯[Evaluation] <Weight average molecular weight> The weight average molecular weight (Mw) of acrylic oligomers and urethane (meth)acrylates was measured using a GPC (Gel Permeation Chromatography) device manufactured by Tosoh (product name "HLC- 8120GPC") for measurement. As a measurement sample, a filtrate obtained by dissolving the base polymer in tetrahydrofuran to obtain a 0.1% by weight solution with a 0.45 μm membrane filter was used. The measurement conditions of GPC are as follows. (Measurement conditions) Column: manufactured by Tosoh Corporation, G7000HXL+GMHXL+GMHXL Column size: 7.8 mm each

×30 cm (Total column length: 90 cm) Column temperature: 40°C・Flow rate: 0.8 mL/min Injection volume: 100 μL Eluent: THF Detector: Differential refractometer (RI) Standard sample: Polystyrene

＜黏著片之儲存彈性模數、玻璃轉移溫度以及tanδ峰值＞ 將積層10片黏著片製成厚度約1.5 mm之材料作為測定用樣品。使用Rheometric Scientific公司製造之「Advanced Rheometric Expansion System(ARES)」，藉由以下條件進行動態黏彈性測定。 (測定條件) 變形模式：扭轉 測定頻率：1 Hz 升溫速度：5℃/分鐘 形狀：平行板 7.9 mm

<Storage elastic modulus, glass transition temperature, and tanδ peak value of the adhesive sheet> A material with a thickness of about 1.5 mm was made by laminating 10 adhesive sheets and used as a sample for measurement. Using "Advanced Rheometric Expansion System (ARES)" manufactured by Rheometric Scientific, dynamic viscoelasticity was measured under the following conditions. (Measurement conditions) Deformation mode: Torsion Measurement frequency: 1 Hz Heating rate: 5°C/min Shape: Parallel plate 7.9 mm

剪切儲存彈性模數藉由根據測定結果讀取各溫度下之儲存彈性模數G'而求出。將損失正切(tanδ)達到極大時之溫度(峰頂溫度)作為黏著片之玻璃轉移溫度。另外，讀取玻璃轉移溫度下之tanδ之值(峰頂值)。The shear storage modulus was obtained by reading the storage modulus G' at each temperature from the measurement results. The temperature (peak top temperature) at which the loss tangent (tan δ) reaches the maximum is taken as the glass transition temperature of the adhesive sheet. In addition, read the value of tanδ (peak top value) at the glass transition temperature.

＜接著力＞ 將輕剝離膜自黏著片剝離，貼合厚度50 μm之PET膜，切割成寬度10 mm×長度100 mm，然後將重剝離膜剝離，利用5 kg之輥壓接於玻璃板，從而製作接著力測定用試樣。將接著力測定用試樣於25℃或65℃之環境下保持30分鐘，然後使用拉伸試驗機，於拉伸速度為300 mm/分鐘、剝離角度為180°之條件下自玻璃板剝離試驗片，測定剝離力。＜Adhesion＞ Peel off the light release film from the adhesive sheet, stick it to a PET film with a thickness of 50 μm, cut it into a width of 10 mm x 100 mm in length, then peel off the heavy release film, and press it to the glass plate with a 5 kg roller to make an adhesive force Samples for measurement. Hold the sample for adhesion measurement at 25°C or 65°C for 30 minutes, and then use a tensile tester to perform a peel test from the glass plate under the conditions of a tensile speed of 300 mm/min and a peeling angle of 180° slices to measure the peel force.

＜霧度＞ 使用將黏著片貼合於厚度800 μm之無鹼玻璃(總光線透射率92%，霧度0.4%)而獲得之試驗片，使用霧度計(村上色彩技術研究所製造之「HM-150」)測定霧度。將用測定值減去無鹼玻璃之霧度(0.4%)而得到之值作為黏著片之霧度。＜Haze＞ Using a test piece obtained by bonding an adhesive sheet to an alkali-free glass with a thickness of 800 μm (total light transmittance 92%, haze 0.4%), a haze meter ("HM-150" manufactured by Murakami Color Technology Laboratory) was used. ) to measure haze. The value obtained by subtracting the haze (0.4%) of the non-alkali glass from the measured value was used as the haze of the adhesive sheet.

＜階差吸收性＞ 將黏著片切割成75 mm×45 mm之尺寸，將輕剝離膜自黏著片剝離，利用輥式層壓機(輥間壓力：0.2 MPa，運送速度：100 mm/分鐘)貼合於切割成100 mm×50 mm之厚度125 μm之PET膜之中央。然後，將重剝離膜剝離，利用輥式層壓機(輥間壓力：0.2 MPa，運送速度：100 mm/分鐘)貼合於在周緣部以框狀印刷有厚度20 μm之黑色油墨之厚度500 μm之玻璃板(100 mm×50 mm)。玻璃板之油墨印刷區域係短邊方向自兩端起5 mm、長邊方向自兩端起15 mm，於距黏著片之四邊之端部5 mm之區域與黑色油墨層相接。利用高壓釜(50℃、0.5 MPa)對該試樣進行30分鐘處理，然後利用倍率20倍之數位顯微鏡進行觀察，對黑色油墨之印刷區域之邊界附近有無氣泡進行確認。＜Gradient absorbency＞ Cut the adhesive sheet into a size of 75 mm × 45 mm, peel off the light release film from the adhesive sheet, and use a roll laminator (roller pressure: 0.2 MPa, conveying speed: 100 mm/min) to stick to the cut 100 The center of a PET film with a thickness of 125 μm in mm×50 mm. Then, peel off the heavy release film, and use a roll laminator (pressure between rolls: 0.2 MPa, conveying speed: 100 mm/min) to bond to a thickness of 500 mm with black ink printed in a frame shape with a thickness of 20 μm on the peripheral part. μm glass plate (100 mm×50 mm). The ink printing area of the glass plate is 5 mm from both ends in the short side direction and 15 mm from both ends in the long side direction, and the area 5 mm from the ends of the four sides of the adhesive sheet is in contact with the black ink layer. The sample was processed in an autoclave (50°C, 0.5 MPa) for 30 minutes, and then observed with a digital microscope with a magnification of 20 times to confirm whether there are bubbles near the boundary of the black ink printing area.

＜自離型膜之剝離性＞ 將黏著片切割成75 mm×45 mm之尺寸，將輕剝離膜自黏著片剝離，利用輥式層壓機(輥間壓力：0.2 MPa，運送速度：100 mm/分鐘)與厚度500 μm之玻璃板(100 mm×50 mm)貼合。於暫時附著於黏著片之重剝離膜之端部貼合拾取帶，以90°之剝離角度進行剝離，將於黏著片與重剝離膜之界面發生剝離之試樣記為OK，將於玻璃板與重剝離膜之界面發生剝離之試樣記為NG。＜Peelability of self-release film＞ Cut the adhesive sheet into a size of 75 mm×45 mm, peel off the light release film from the adhesive sheet, and use a roll laminator (roller pressure: 0.2 MPa, conveying speed: 100 mm/min) with a glass with a thickness of 500 μm Board (100 mm × 50 mm) fit. Attach the pick-up tape to the end of the heavy-release film temporarily attached to the adhesive sheet, and peel it off at a peeling angle of 90°. The sample that peels off at the interface between the adhesive sheet and the heavy-release film is marked as OK, and the sample is placed on the glass plate The sample that peeled off from the interface with the heavy peeling film was recorded as NG.

＜層間接著性＞ (試驗用試樣之製作) 將黏著片切割成75 mm×45 mm之尺寸，將輕剝離膜自黏著片剝離，利用輥式層壓機(輥間壓力：0.2 MPa，運送速度：100 mm/分鐘)貼合於厚度500 μm之玻璃板(100 mm×50 mm)之中央。自黏著片剝離重剝離膜，藉由真空壓接(面壓0.3 MPa，壓力100 Pa)貼合於周緣部以框狀印刷有厚度30 μm之黑色油墨之厚度500 μm之玻璃板(50 mm×100 mm，油墨印刷區域與在階差吸收性試驗中使用之區域相同)。藉由高壓釜(50℃，0.5 MPa)對該試樣進行30分鐘處理，然後利用金屬鹵化物燈(300 mW/cm² )自具有黑色油墨之印刷層之玻璃板側照射紫外線而進行硬化，將聚合率提高至99%。＜Interlayer Adhesion＞ (Preparation of test samples) Cut the adhesive sheet into a size of 75 mm×45 mm, peel the light release film from the adhesive sheet, and use a roll laminator (pressure between rolls: 0.2 MPa, transport Speed: 100 mm/min) attached to the center of a glass plate (100 mm×50 mm) with a thickness of 500 μm. Peel the heavy release film from the adhesive sheet, and attach it to a glass plate (50 mm× 100 mm, the ink printed area is the same as that used in the step absorbency test). The sample was treated in an autoclave (50°C, 0.5 MPa) for 30 minutes, and then cured by irradiating ultraviolet light from the glass plate side with the printed layer of black ink with a metal halide lamp (300 mW/cm ² ), Increase polymerization rate to 99%.

將上述試樣於60℃之環境下保持30分鐘，然後如圖5A所示，將厚度200 μm之聚苯乙烯片於兩片玻璃板之間自黏著片之端部***至1 mm之距離後保持10秒鐘。利用倍率20倍之數位顯微鏡對黏著片之端部進行觀察。將產生條紋狀氣泡(參照圖5B)或產生黏著片自玻璃板之剝離之試樣記為NG，將氣泡以及剝離均未產生之試樣記為OK。The above sample was kept at 60°C for 30 minutes, and then as shown in Figure 5A, a polystyrene sheet with a thickness of 200 μm was inserted between the two glass plates from the end of the adhesive sheet to a distance of 1 mm. Hold for 10 seconds. The end of the adhesive sheet was observed using a digital microscope with a magnification of 20 times. A sample in which streaked air bubbles (see FIG. 5B ) or peeling of the adhesive sheet from the glass plate occurred was designated as NG, and a sample in which neither air bubbles nor peeling occurred was designated as OK.

＜耐衝擊性＞ 將未設置有黑色油墨之印刷層之玻璃板之尺寸變更為100 mm×70 mm，除此以外與上述層間接著性試驗用試樣之製作同樣地，於黏著片之兩面貼合玻璃板，進行高壓釜處理以及黏著劑之硬化，製作試驗用試樣。如圖6所示，以使設置印刷層76之玻璃板7為下側之方式，將試驗用試樣95之短邊方向之兩端載置於隔著60 mm之間隔而配置之台93上，利用黏著帶(未圖示)將未設置印刷層之玻璃板5之端部之上表面固定於台80上。將於台93上利用黏著帶固定之試驗用試樣95於-5℃之環境下保持24小時，然後於室溫取出後40秒以內，使質量11 g之金屬球97自300 mm高度落下至玻璃板7上，進行耐衝擊性試驗。＜Shock resistance＞ Except that the size of the glass plate without the printed layer of black ink was changed to 100 mm x 70 mm, the glass plate was attached to both sides of the adhesive sheet in the same way as the preparation of the above-mentioned interlayer adhesion test sample. Autoclave treatment and hardening of the adhesive to prepare test samples. As shown in FIG. 6 , the both ends of the test sample 95 in the short side direction are placed on a stage 93 arranged at a distance of 60 mm so that the glass plate 7 provided with the printed layer 76 is on the lower side. , using an adhesive tape (not shown) to fix the upper surface of the end portion of the glass plate 5 not provided with a printed layer on the stage 80 . The test sample 95 fixed on the platform 93 with an adhesive tape was kept at -5°C for 24 hours, and then within 40 seconds after being taken out at room temperature, a metal ball 97 with a mass of 11 g was dropped from a height of 300 mm to On the glass plate 7, an impact resistance test was performed.

於耐衝擊性試驗中，為了使金屬球之落下位置固定，使用筒狀引導件99，於印刷層76之印刷區域之框之內緣之沿短邊方向以及長邊方向各自與角間隔10 mm之位置，使金屬球97落下。進行兩次試驗，將在任一個試驗中均未發生玻璃板之剝離之試樣記為OK，將兩次中之任一次或兩次發生玻璃板之剝離之試樣記為NG。In the impact resistance test, in order to fix the falling position of the metal ball, a cylindrical guide 99 is used, and the inner edge of the frame of the printing area of the printing layer 76 is separated by 10 mm from the corner along the short side direction and the long side direction. The position makes the metal ball 97 fall. The test was performed twice, and the sample in which the peeling of the glass plate did not occur in any of the tests was designated as OK, and the sample in which the peeling of the glass plate occurred in either one or two of the two tests was designated as NG.

＜硬化後之黏著片之物性＞ 於各實施例以及比較例之黏著片之製作中，變更紫外線之照射時間，藉此製作聚合率為99%之黏著片，與上述同樣地，測定黏彈性(儲存彈性模數、玻璃轉移溫度以及tanδ峰)、霧度以及接著力。關於實施例4、比較例4以及比較例5，由於黏著劑之組成與實施例6相同，因此未實施硬化後之黏著片之物性之測定。＜Physical properties of hardened adhesive sheet＞ In the production of the adhesive sheets of each example and comparative example, the irradiation time of ultraviolet rays was changed to produce an adhesive sheet with a polymerization rate of 99%, and the viscoelasticity (storage elastic modulus, glass transition temperature and tanδ peak), haze and adhesion. Regarding Example 4, Comparative Example 4, and Comparative Example 5, since the composition of the adhesive is the same as that of Example 6, the physical properties of the adhesive sheet after hardening were not measured.

[評價結果] 將各黏著片之製作中所使用之黏著劑組合物之調配示於表1-1以及表1-2中，將評價結果示於表2-1以及表2-2中。再者，於表1-1以及表1-2中，各成分藉由下述簡稱記載。 ＜丙烯酸系單體＞ BA ：丙烯酸丁酯 2HEA ：丙烯酸2-乙基己基酯 CHA ：丙烯酸環己酯 NVP ：N-乙烯基-2-吡咯烷酮 4HBA ：丙烯酸4-羥基丁基酯 2HEA ：丙烯酸2-羥基乙基酯 ISTA ：丙烯酸異硬脂酯[Evaluation results] The formulation of the adhesive composition used in the preparation of each adhesive sheet is shown in Table 1-1 and Table 1-2, and the evaluation result is shown in Table 2-1 and Table 2-2. In addition, in Table 1-1 and Table 1-2, each component is described by the following abbreviation. ＜Acrylic monomer＞ BA: butyl acrylate 2HEA: 2-ethylhexyl acrylate CHA: cyclohexyl acrylate NVP: N-vinyl-2-pyrrolidone 4HBA: 4-Hydroxybutyl Acrylate 2HEA: 2-Hydroxyethyl Acrylate ISTA: Isostearyl Acrylate

＜丙烯酸胺基甲酸酯＞ UV-3300B：日本合成化學工業製造之「UV-3300B」(重量平均分子量為約12000，玻璃轉移溫度為-30℃之二丙烯酸聚醚胺基甲酸酯) 3400：重量平均分子量為約3400之二丙烯酸聚醚胺基甲酸酯 UA-4200：新中村化學工業製造之「UA-4200」(重量平均分子量為約1000之二丙烯酸聚醚胺基甲酸酯) UN-350：根上工業製造之「Art Resin UN-350」(重量平均分子量為約12500，玻璃轉移溫度為-57℃之二丙烯酸聚酯胺基甲酸酯) UV-3000B：日本合成化學工業製造之「UV-3000B」(重量平均分子量為約18000，玻璃轉移溫度為-39℃之二丙烯酸聚酯胺基甲酸酯) UV-3010B：日本合成化學工業製造之「UV-3010B」(重量平均分子量為約11000之二丙烯酸聚酯胺基甲酸酯) 單丙烯酸胺基甲酸酯：重量平均分子量為約1300之單丙烯酸聚醚胺基甲酸酯) ＜多官能丙烯酸酯＞ HDDA：己二醇二丙烯酸酯 ＜光聚合起始劑＞ Irg651：Irgacure651(2,2-二甲氧基-1,2-二苯基乙烷-1-酮) Irg184：Irgacure184(1-羥基環己基-苯基-酮)＜Urethane Acrylate＞ UV-3300B: "UV-3300B" manufactured by Nippon Synthetic Chemical Industry (diacrylic polyether urethane with a weight average molecular weight of about 12,000 and a glass transition temperature of -30°C) 3400: Diacrylic polyether urethane with a weight average molecular weight of about 3400 UA-4200: "UA-4200" manufactured by Shin-Nakamura Chemical Industry Co., Ltd. (diacrylic polyether urethane with a weight average molecular weight of about 1,000) UN-350: "Art Resin UN-350" manufactured by Negami Industry (diacrylic polyester urethane with a weight average molecular weight of about 12,500 and a glass transition temperature of -57°C) UV-3000B: "UV-3000B" manufactured by Nippon Synthetic Chemical Industry (diacrylic polyester urethane with a weight average molecular weight of about 18,000 and a glass transition temperature of -39°C) UV-3010B: "UV-3010B" manufactured by Nippon Synthetic Chemical Industry (diacrylate polyester urethane with a weight average molecular weight of about 11,000) Monoacrylate urethane: monoacrylate polyether urethane with a weight average molecular weight of about 1300) ＜Multifunctional Acrylate＞ HDDA: hexanediol diacrylate ＜Photopolymerization Initiator＞ Irg651: Irgacure651 (2,2-dimethoxy-1,2-diphenylethan-1-one) Irg184: Irgacure184 (1-hydroxycyclohexyl-phenyl-ketone)

[表1-1]

[Table 1-1]

[表1-2]

[Table 1-2]

[表2-1]

[table 2-1]

[表2-2]

[Table 2-2]

於使用藉由以丙烯酸丁酯作為主要單體之丙烯酸系單體之預聚合而獲得之預聚物組合物中添加二丙烯酸胺基甲酸酯等黏著劑組合物之實施例1、2中，半硬化之黏著片之階差吸收性優異並且無糊劑殘留，於使用完全硬化後之黏著片之評價中，層間接著性以及落下衝擊耐久性均良好。In Examples 1 and 2 in which an adhesive composition such as urethane diacrylate was added to a prepolymer composition obtained by prepolymerizing an acrylic monomer with butyl acrylate as the main monomer, The semi-cured adhesive sheet has excellent step absorption and no paste residue. In the evaluation using the fully cured adhesive sheet, the interlayer adhesion and drop impact durability are good.

於使用低分子量之二丙烯酸胺基甲酸酯之比較例1中，於光硬化前後之任一種情形時，黏著片對於被接著體之接著力均較小，層間接著性以及落下衝擊耐久性均較差。於增大二丙烯酸胺基甲酸酯之添加量之比較例2中，黏著片之霧度較高，透明性降低。另外，硬化前之黏著片之G'_{25 ℃} 較大，因此階差吸收性較差。於使用單丙烯酸胺基甲酸酯之比較例3中，光硬化後之黏著片之剪切儲存彈性模數較低，接著耐久性較差。In Comparative Example 1 using low-molecular-weight urethane diacrylate, the adhesion force of the adhesive sheet to the adherend was small, and the interlayer adhesion and drop impact durability were both low before and after photocuring. poor. In Comparative Example 2 in which the added amount of urethane diacrylate was increased, the haze of the adhesive sheet was high, and the transparency decreased. In addition, the G' _{25 ℃} of the adhesive sheet before hardening is relatively large, so the absorption of step difference is poor. In Comparative Example 3 using urethane monoacrylate, the shear storage elastic modulus of the adhesive sheet after photocuring was low, and the subsequent durability was poor.

於變更預聚物形成用組合物中之丙烯酸系單體之組成之實施例3及實施例5、以及實施例6及實施例7中，亦與實施例1、2同樣地顯示出良好之接著特性。In Example 3 and Example 5, and Example 6 and Example 7 in which the composition of the acrylic monomer in the composition for forming a prepolymer was changed, similarly to Examples 1 and 2, good adhesion was shown. characteristic.

於使用與實施例3相同之黏著劑組合物，使聚合率降低至92%之實施例4中，與實施例3相比，半硬化狀態之黏著片之玻璃轉移溫度降低，隨之，G'_{25 ℃} 以及G'_{80 ℃} 降低。於使聚合率進而降低之比較例4中，半硬化狀態之黏著片之玻璃轉移溫度、G'_{25 ℃} 以及G'_{80 ℃} 進而降低，接著力不充分。另一方面，於將聚合率設為99%之比較例5中，因G'_{25 ℃} 之上升引起階差吸收性不充分。In Example 4, which uses the same adhesive composition as in Example 3 to reduce the polymerization rate to 92%, compared with Example 3, the glass transition temperature of the adhesive sheet in the semi-hardened state is lowered, and accordingly, G' _{25 °C} and G' _{80 °C} decrease. In Comparative Example 4 in which the polymerization rate was further lowered, the glass transition temperature, G' _{25 °C} , and G' _{80 °C} of the semi-cured adhesive sheet were further lowered, and the adhesive force was insufficient. On the other hand, in Comparative Example 5 in which the polymerization rate was set to 99%, the step absorbability was insufficient due to an increase in G' _{25 °C} .

於不使用胺基甲酸酯系材料而藉由調整丙烯酸系單體之組成而使玻璃轉移溫度降低之比較例6中，光硬化後之黏著片之G'_{25 ℃} 以及G'_{80 ℃} 較小，接著可靠性較差。於藉由提高丙烯酸系單體成分中之極性單體(NVB以及4HBA)之比率而提高凝集性之比較例7中，接著性良好，但由於玻璃轉移溫度較高，因此耐衝擊性降低。於比較例10中亦發現同樣之傾向。In Comparative Example 6 in which the glass transition temperature was lowered by adjusting the composition of the acrylic monomer without using urethane-based materials, the G' _{25 ℃} and G' _{80 ℃} of the adhesive sheet after photocuring were smaller , followed by poor reliability. In Comparative Example 7, in which coagulation was improved by increasing the ratio of polar monomers (NVB and 4HBA) in the acrylic monomer component, the adhesiveness was good, but the impact resistance decreased due to the high glass transition temperature. The same tendency was also found in Comparative Example 10.

於提高黏著劑組合物中之多官能丙烯酸酯之比率之比較例8中，tanδ之峰頂值較小、黏性較低，因此，接著力不充分，耐衝擊性亦較差。於藉由低分子量之胺基甲酸酯二丙烯酸酯導入交聯結構之比較例9中亦發現同樣之傾向。於該等比較例中，認為丙烯酸系聚合物鏈之主要單體為丙烯酸C₈ 烷基酯(丙烯酸2-乙基己基酯)亦為與主要單體為丙烯酸C₄ 烷基酯(丙烯酸丁酯)之實施例1～7等相比tanδ較小之因素之一。In Comparative Example 8 in which the ratio of the multifunctional acrylate in the adhesive composition was increased, the peak value of tanδ was small and the viscosity was low, so the adhesive force was insufficient and the impact resistance was also poor. The same tendency was also found in Comparative Example 9 in which a crosslinked structure was introduced by a low molecular weight urethane diacrylate. In these comparative examples, it is considered that the main monomer of the acrylic polymer chain is C ₈ alkyl acrylate (2-ethylhexyl acrylate) and the main monomer is C ₄ alkyl acrylate (butyl acrylate). ) is one of the factors that are smaller than tanδ in Examples 1-7.

由該等結果可知，含有使用具有特定分子量之二丙烯酸胺基甲酸酯而於丙烯酸系聚合物鏈導入交聯結構之基礎聚合物之黏著片，以低玻璃轉移溫度下亦顯示出較高之剪切儲存彈性模數，並且tanδ較大，因此能夠兼具接著耐久性及耐衝擊性。From these results, it can be seen that the adhesive sheet containing the base polymer in which a crosslinked structure is introduced into the acrylic polymer chain by using urethane diacrylate having a specific molecular weight exhibits a higher glass transition temperature. Shear storage elastic modulus, and tanδ is relatively large, so it can have both adhesion durability and impact resistance.

1、2‧‧‧離型膜 3‧‧‧偏光板 4‧‧‧黏著片 5‧‧‧黏著片 6‧‧‧圖像顯示單元 7‧‧‧前面透明板 9‧‧‧殼體 10‧‧‧圖像顯示面板 100‧‧‧圖像顯示裝置1.2‧‧‧Release film 3‧‧‧Polarizer 4‧‧‧adhesive sheet 5‧‧‧adhesive sheet 6‧‧‧Image display unit 7‧‧‧Front transparent board 9‧‧‧Shell 10‧‧‧Image display panel 100‧‧‧image display device

圖1係表示附離型膜之黏著片之構成例之剖視圖。 圖2係表示圖像顯示裝置之構成例之剖視圖。 圖3以及圖4係表示附黏著片之光學膜之積層構成例的剖視圖。 圖5A係表示層間接著性試驗之情形之照片，圖5B係於層間接著性試驗中產生條紋狀氣泡之試樣之觀察照片。 圖6係表示耐衝擊試驗中之試樣之配置之示意圖。Fig. 1 is a cross-sectional view showing a configuration example of an adhesive sheet with a release film. FIG. 2 is a cross-sectional view showing a configuration example of an image display device. 3 and 4 are cross-sectional views showing an example of a layered structure of an optical film with an adhesive sheet attached. Fig. 5A is a photograph showing the state of the interlayer adhesion test, and Fig. 5B is an observation photograph of a sample in which streaked bubbles were generated in the interlayer adhesion test. Fig. 6 is a schematic diagram showing the arrangement of samples in the impact resistance test.

1、2‧‧‧離型膜 1.2‧‧‧Release film

5‧‧‧黏著片 5‧‧‧adhesive sheet

Claims (12)

一種黏著片，其為將含有丙烯酸系基礎聚合物、丙烯酸系低聚物以及光硬化性化合物之黏著劑組合物以層狀形成之光硬化性之黏著片，其中上述丙烯酸系基礎聚合物係丙烯酸系聚合物鏈藉由胺基甲酸酯系鏈段進行交聯而成者，上述胺基甲酸酯系鏈段之重量平均分子量為4000~50000，上述丙烯酸系低聚物之重量平均分子量為1000~30000，玻璃轉移溫度為20℃以上，上述丙烯酸系低聚物之含量相對於上述丙烯酸系基礎聚合物100重量份為0.5~20重量份；該黏著片之霧度為1%以下，對於玻璃之接著力為1.5N/10mm以上，於溫度25℃下之剪切儲存彈性模數為0.15MPa以下，且於將上述黏著劑組合物硬化並將聚合率設為99%時，玻璃轉移溫度為-3℃以下，並且溫度25℃下之剪切儲存彈性模數為0.16MPa以上。 An adhesive sheet, which is a photocurable adhesive sheet formed by layering an adhesive composition containing an acrylic base polymer, an acrylic oligomer, and a photocurable compound, wherein the acrylic base polymer is acrylic acid It is formed by cross-linking polymer chains through urethane-based chain segments. The weight-average molecular weight of the above-mentioned urethane-based chain segments is 4,000~50,000, and the weight-average molecular weight of the above-mentioned acrylic oligomers is 1000~30000, the glass transition temperature is above 20°C, the content of the above-mentioned acrylic oligomer is 0.5~20 parts by weight relative to 100 parts by weight of the above-mentioned acrylic base polymer; the haze of the adhesive sheet is 1% or less. The adhesive force of the glass is 1.5N/10mm or more, the shear storage modulus at 25°C is 0.15MPa or less, and when the above adhesive composition is hardened and the polymerization rate is set to 99%, the glass transition temperature It is below -3°C, and the shear storage elastic modulus at a temperature of 25°C is above 0.16MPa. 如請求項1之黏著片，其中上述黏著劑組合物之聚合率為90~98%。 The adhesive sheet according to claim 1, wherein the polymerization rate of the adhesive composition is 90-98%. 如請求項1或2之黏著片，其中玻璃轉移溫度為-5℃以下。 The adhesive sheet according to claim 1 or 2, wherein the glass transition temperature is below -5°C. 如請求項1或2之黏著片，其中損失正切之峰頂值為1.6以上。 The adhesive sheet according to claim 1 or 2, wherein the peak value of the loss tangent is 1.6 or more. 如請求項1或2之黏著片，其中於將上述黏著劑組合物硬化並將聚合率設為99%時，損失正切之峰頂值為1.5以上。 The adhesive sheet according to claim 1 or 2, wherein the peak value of the loss tangent is 1.5 or more when the adhesive composition is hardened and the polymerization rate is 99%. 如請求項1或2之黏著片，其中於上述丙烯酸系基礎聚合物中，上述胺基甲酸酯系鏈段之含量相對於上述丙烯酸系聚合物鏈100重量份，為3~30重量份。 The adhesive sheet according to claim 1 or 2, wherein in the acrylic base polymer, the content of the urethane segment is 3 to 30 parts by weight relative to 100 parts by weight of the acrylic polymer chain. 如請求項1或2之黏著片，其中於上述丙烯酸系基礎聚合物中，藉由構成上述丙烯酸系聚合物鏈之單體成分與在末端具有(甲基)丙烯醯基之二胺基甲酸酯(甲基)丙烯酸酯之共聚而於上述丙烯酸系聚合物鏈導入由上述胺基甲酸酯系鏈段形成之交聯結構。 The adhesive sheet according to claim 1 or 2, wherein in the above-mentioned acrylic base polymer, the monomer component constituting the above-mentioned acrylic polymer chain and diurethane formic acid having a (meth)acryl group at the end The copolymerization of ester (meth)acrylate introduces a cross-linked structure formed by the above-mentioned urethane-based chain segment into the above-mentioned acrylic polymer chain. 如請求項1或2之黏著片，其中相對於構成上述丙烯酸系聚合物鏈之單體成分總量，具有碳數6以下之鏈狀烷基之(甲基)丙烯酸烷基酯之量為30~80重量%。 The adhesive sheet according to claim 1 or 2, wherein the amount of alkyl (meth)acrylate having a chain alkyl group having 6 or less carbon atoms is 30 relative to the total amount of monomer components constituting the acrylic polymer chain ~80% by weight. 一種圖像顯示裝置之製造方法，其為製造於視認側表面配置具有階差部分之透明構件之圖像顯示裝置之方法，且使如請求項1至8中任一項之黏著片與上述透明構件貼合，然後對上述黏著片照射活性光線，藉此進行上述黏著片之光硬化。 A method of manufacturing an image display device, which is a method of manufacturing an image display device in which a transparent member having a step portion is disposed on the viewing side surface, and the adhesive sheet according to any one of claims 1 to 8 is combined with the above-mentioned transparent The components are bonded together, and then the above-mentioned adhesive sheet is irradiated with active light to thereby perform photocuring of the above-mentioned adhesive sheet. 一種黏著片之製造方法，其為如請求項1至8中任一項之黏著片之製造方法，且 將含有丙烯酸系單體及/或其部分聚合物、以及重量平均分子量為4000~50000之二胺基甲酸酯(甲基)丙烯酸酯之組合物以層狀塗佈於基材上，然後對上述組合物照射活性光線而進行光硬化。 A method of manufacturing an adhesive sheet, which is the method of manufacturing an adhesive sheet according to any one of claims 1 to 8, and A composition containing acrylic monomers and/or partial polymers thereof, and diurethane (meth)acrylates with a weight average molecular weight of 4,000 to 50,000 is coated on the substrate in layers, and then The above-mentioned composition is irradiated with active light to be photocured. 如請求項10之黏著片之製造方法，其中於上述組合物中，上述二胺基甲酸酯(甲基)丙烯酸酯之含量相對於上述丙烯酸系單體及其部分聚合物之合計100重量份，為3~30重量份。 The method for producing an adhesive sheet according to claim 10, wherein in the above composition, the content of the above diurethane (meth)acrylate is 100 parts by weight relative to the total of the above acrylic monomer and its partial polymer , being 3 to 30 parts by weight. 如請求項10或11之黏著片之製造方法，其中上述二胺基甲酸酯(甲基)丙烯酸酯之玻璃轉移溫度為0℃以下。 The method for producing an adhesive sheet according to claim 10 or 11, wherein the glass transition temperature of the above-mentioned diurethane (meth)acrylate is 0° C. or lower.

Images