Antistatic protective film and adhesive composition

Abstract

The invention discloses an antistatic protective film and adhesive composition. The adhesive composition includes 100 parts by weight of a polymer resin, 3 to 15 parts by weight of a curing agent, 0.2 to 3 parts by weight of an accelerator, and 0.5 to 5 parts by weight of an antistatic agent. The monomers for synthesizing the polymer resin comprise a first monomer and a second monomer, the first monomer is the monomer with the highest carbon number in the monomers for synthesizing the polymer resin, the second monomer is the monomer with the second highest carbon number in the monomers for synthesizing the polymer resin, and the mole number ratio of the second monomer to the first monomer is 0.15-6. Monomers for synthesizing the polymer resin comprise an acrylic monomer and a methacrylic acid monomer, and the carbon number of the acrylic monomer is higher than that of the methacrylic acid monomer. When the antistatic protective film is attached to a base material, the antistatic protective film has good attaching smoothness and adhesion durability.

Description

TECHNICAL FIELD

[0001] The present application relates to an antistatic protective film and adhesive composition, in particular to an antistatic protective film and adhesive composition with good adhesion and adhesion durability. BACKGROUND

[0002] With the development of wearable devices, Internet of Things, artificial intelligence and 5G communication, the global demand for semiconductor is rapidly increasing, which also drives the market demand for semiconductor adhesive tape (i.e. the protective film of the present application). The uses of semiconductor adhesive tape mainly include cleaning wafer surface, adhering hetero-interface, back grinding and wafer cutting.

[0003] As the volume of electronic devices gradually decreases, the semiconductor chips carried by them are also gradually thinned. Thin semiconductor chips are more likely to be damaged during processing, so the quality of semiconductor adhesive tape is extremely important and will directly affect the yield of semiconductor chips.

[0004] In terms of properties, semiconductor adhesive tape needs to have sufficient physical strength to achieve the effect of protecting the chip in semiconductor processing. Semiconductor adhesive tape also needs to have the characteristics of uniform adhesion, easy to remove, and no residual glue. Semiconductor chips are a delicate laminated structure composed of thin layers of different materials. If the adhesion of semiconductor adhesive tape is too high, it may damage the laminated structure, and residual glue may also contaminate the semiconductor chip. Semiconductor processing involves exposure procedures. If bubbles are generated between the semiconductor adhesive tape and the semiconductor chip, it will affect the accuracy of the circuit during exposure. Therefore, the flatness of the semiconductor adhesive tape attached to the wafer is also very important.

[0005] In addition, when the semiconductor adhesive tape is removed from the wafer, a peeling electrostatic voltage may be generated, which may damage the circuit components on the integrated circuit. In the case of increasingly fine line width and line spacing on integrated circuits, the breakdown voltage of integrated circuit components also decreases. Accordingly, the peeling electrostatic voltage of semiconductor adhesive tape needs to be controlled within the range of +0.7kV to -0.7kV.

[0006] Therefore, how to improve the quality of semiconductor adhesive tape by improving the composition to overcome the above-mentioned defects has become one of the important issues to be solved in this industry. SUMMARY

[0007] The technical problem to be solved by the present application is to provide an antistatic protective film and adhesive composition to overcome the deficiencies of the prior art.

[0008] To solve the above technical problems, one of the technical solutions adopted by the present application is to provide an adhesive composition. The adhesive composition includes 100 parts by weight of a polymer resin, 3 to 15 parts by weight of a curing agent, 0.2 to 3 parts by weight of an accelerator, and 0.5 to 5 parts by weight of an antistatic agent. The monomers of the synthetic polymer resin include a first monomer and a second monomer, the first monomer is the monomer with the highest carbon number in the monomers of the synthetic polymer resin, the second monomer is the monomer with the second highest carbon number in the monomers of the synthetic polymer resin, and the molar ratio of the second monomer to the first monomer is 0.15 to 6. The monomers of the synthetic polymer resin include acrylic monomers and methacrylic monomers, and the carbon number of the acrylic monomers is higher than that of the methacrylic monomers.

[0009] Further, the carbon number of the methacrylic monomers is 4 to 12, and the carbon number of the acrylic monomers is 13 to 20.

[0010] Further, the first monomer is an acrylic monomer, and the second monomer is a methacrylic monomer.

[0011] Further, the weight average molecular weight of the polymer resin is 450,000 g / mol to 600,000 g / mol.

[0012] Further, the methacrylic monomers include methacrylic acid, 2-phenoxyethyl methacrylate, and hydroxybutyl methacrylate.

[0013] Further, based on 100% by weight of the total weight of the monomers of the synthetic polymer resin, the content of methacrylic acid is 3% to 6% by weight, the content of 2-phenoxyethyl methacrylate is 8% to 60% by weight, and the content of hydroxybutyl methacrylate is 20% to 30% by weight.

[0014] Further, the acrylic monomers include t-butylcyclohexyl acrylate.

[0015] Further, based on 100% by weight of the total weight of the monomers of the synthetic polymer resin, the content of t-butylcyclohexyl acrylate is 10% to 60% by weight.

[0016] Further, the curing agent is a polyisocyanate curing agent.

[0017] Further, the accelerator is a metal complex.

[0018] Further, the accelerator is aluminum acetylacetonate.

[0019] Further, the antistatic agent is a non-ionic antistatic agent.

[0020] To address the aforementioned technical problems, another technical solution adopted by the present invention is to provide an antistatic protective film. The antistatic protective film includes a carrier layer, a conductive layer, an adhesive layer, and a release layer. The adhesive layer is formed from the aforementioned adhesive composition and is disposed between the carrier layer and the release layer. The conductive layer is disposed on at least one surface of the carrier layer.

[0021] Furthermore, the surface tension of the release layer is 40 dynes / cm to 60 dynes / cm.

[0022] Furthermore, the conductive layer is formed from poly(3,4-dioxyethylthiophene):polystyrene sulfonic acid.

[0023] One of the beneficial effects of the present invention is that the antistatic protective film and adhesive composition provided by the present invention can achieve good adhesion smoothness and adhesion durability when the antistatic protective film is applied to the substrate by means of the technical solutions of "the molar ratio of the second monomer to the first monomer is 0.15 to 6" and "the carbon number of the acrylic monomer is higher than the carbon number of the methacrylic acid monomer".

[0024] To further understand the features and technical content of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings provided are for reference and illustration only and are not intended to limit the present invention. Attached Figure Description

[0025] Figure 1 This is a side view of the protective film according to the first embodiment of the present invention.

[0026] Figure 2 This is a side view of the protective film according to the second embodiment of the present invention.

[0027] Figure 3 This is a side view of the protective film according to the third embodiment of the present invention. Detailed Implementation

[0028] The following specific examples illustrate the embodiments of the "antistatic protective film and adhesive composition" disclosed in this invention. Those skilled in the art can understand the advantages and effects of this invention from the content disclosed in this specification. This invention can be implemented or applied through other different specific embodiments, and the details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of this invention. Furthermore, the accompanying drawings of this invention are for simple illustrative purposes only and are not depictions of actual dimensions, as stated in advance. The following embodiments will further describe the relevant technical content of this invention in detail, but the disclosed content is not intended to limit the scope of protection of this invention. In addition, the term "or" used herein should be interpreted to include, depending on the actual situation, any combination of any one or more of the associated listed items.

[0029] To avoid reducing the yield of semiconductor chips, this invention provides an antistatic protective film that can be smoothly attached to a wafer and easily peeled off without residue. The antistatic protective film of this invention exhibits a peel strength of less than 140 gf / 25 mm on stainless steel substrates, silicon wafer substrates, and gold-plated substrates, and the peel voltage generated during removal is within the range of +0.7 kV to -0.7 kV. Therefore, removing the antistatic protective film will not damage the chip structure or cause electrostatic discharge to the electronic components. Furthermore, the antistatic protective film of this invention has excellent adhesion persistence, maintaining more than 88% of its original adhesion even after prolonged use.

[0030] Please see Figure 1 As shown, the antistatic protective film of the present invention includes: a carrier layer 1, a conductive layer 2, an adhesive layer 3, and a release layer 4. The conductive layer 2 is disposed on at least one surface of the carrier layer 1, and the adhesive layer 3 is disposed between the carrier layer 1 and the release layer 4.

[0031] exist Figure 1 In the illustrated embodiment, the conductive layer 2 is disposed on two opposite surfaces of the carrier layer 1, giving the carrier layer 1 the property of being conductive on both sides (i.e., a double-sided conductive carrier layer). The adhesive layer 3 is disposed between the carrier layer 1 and the release layer 4 and is in contact with the conductive layer 2, so as to achieve the effect of attaching the antistatic protective film to various substrates.

[0032] Please see Figure 2 and Figure 3 As shown, the conductive layer 2 can also be disposed on only one surface of the carrier layer 1, i.e., a single-sided conductive carrier layer is manufactured. In the antistatic protective film of the second embodiment of the present invention ( Figure 2 The conductive layer 2 is disposed on the side of the carrier layer 1 away from the adhesive layer 3. Therefore, the adhesive layer 3 does not contact the conductive layer 2, but is directly disposed between the carrier layer 1 and the release layer 4. In the antistatic protective film of the third embodiment of the present invention ( Figure 3 The conductive layer 2 is disposed between the carrier layer 1 and the adhesive layer 3, and the adhesive layer 3 directly contacts the conductive layer 2 and the release layer 4.

[0033] Before use, the release layer 4 is peeled off to allow the adhesive layer 3 to contact the substrate surface, achieving the effect of attaching the antistatic protective film. The release layer 4 is only temporarily attached to the adhesive layer 3; therefore, the bonding force between the adhesive layer 3 and the carrier layer 1 (conductive layer 2) is higher than the bonding force between the adhesive layer 3 and the release layer 4. The thickness of the adhesive layer 3 can be from 10 micrometers to 30 micrometers, for example, a positive integer between 10 and 30 micrometers.

[0034] The materials of the carrier layer 1 and the release layer 4 can be selected according to actual needs. For example, the materials of the carrier layer 1 and the release layer 4 can be polyethylene terephthalate or polybutylene terephthalate.

[0035] In one exemplary embodiment, the surface tension of the release layer 4 is 40 dynes / cm to 60 dynes / cm, so that the release layer 4 can be flatly attached to the adhesive layer 3, which helps to maintain the appearance of the protective film and maintain the adhesion quality of the adhesive layer 3.

[0036] The material of conductive layer 2 can be a conductive polymer resin, such as, but not limited to, poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonate), PEDOT:PSS. The thickness of conductive layer 2 can be from 0.05 micrometers to 0.5 micrometers, for example, 0.1 micrometers, 0.2 micrometers, 0.3 micrometers or 0.4 micrometers.

[0037] The adhesive layer 3 of the present invention is formed from an adhesive composition comprising a polymer resin, a curing agent, an accelerator, an antistatic agent, and a solvent. The total weight of the polymer resin is 100 parts by weight, the curing agent content is 3 to 15 parts by weight, the accelerator content is 0.2 to 3 parts by weight, the antistatic agent content is 0.5 to 5 parts by weight, and the solvent content is 80 to 120 parts by weight. In some embodiments, the curing agent content can be a positive integer between 3 and 15 parts by weight, the accelerator content can be a positive integer between 0.2 and 3 parts by weight, and the antistatic agent content can be a positive integer between 0.5 and 5 parts by weight.

[0038] By adjusting the composition, the polymer resin of the present invention can possess appropriate peel strength and good durability. In the monomers used to synthesize the polymer resin, the present invention further controls the proportion of monomers with higher carbon numbers. For ease of explanation, the monomer with the highest carbon number in the monomers used to synthesize the polymer resin is referred to as the first monomer, and the monomer with the second highest carbon number in the monomers used to synthesize the polymer resin is referred to as the second monomer.

[0039] The present invention controls the molar ratio of the second monomer to the first monomer to be between 0.15 and 6. This allows the adhesive layer 3 formed by the adhesive composition to adhere smoothly to the substrate without generating air bubbles, exhibiting superior adhesive durability. Furthermore, no adhesive residue is generated after removing the adhesive layer 3. In other embodiments, the molar ratio of the second monomer to the first monomer can be 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, or 5.5.

[0040] Polymer resins are polymerized from acrylic acid monomers and methacrylic acid monomers. To adjust the adhesion of polymer resins, methacrylic acid monomers with lower carbon numbers are selected to improve the viscosity and physical strength of the polymer resins, while acrylic acid monomers with higher carbon numbers are selected to reduce the surface tension of the polymer resins and improve their hydrophobicity.

[0041] In one exemplary embodiment, the methacrylic acid monomer has a lower carbon number than the acrylic acid monomer in the monomers used to synthesize the polymer resin. Specifically, the methacrylic acid monomer has 4 to 12 carbon atoms, and the acrylic acid monomer has 13 to 20 carbon atoms.

[0042] Therefore, in the monomers used to synthesize the polymer resin, the first monomer is an acrylic acid monomer, and the second monomer can be either an acrylic acid monomer or a methacrylic acid monomer. In a preferred embodiment, the first monomer is an acrylic acid monomer, and the second monomer is a methacrylic acid monomer.

[0043] Furthermore, in order for the polymer resin to subsequently cure and form an adhesive layer, the methacrylic acid monomer and the acrylic acid monomer contain at least one monomer with a hydroxyl group. That is, at least one methacrylic acid monomer has a hydroxyl group and / or at least one acrylic acid monomer has a hydroxyl group. In a preferred embodiment, the methacrylic acid monomer includes a monomer with a hydroxyl group.

[0044] In one exemplary embodiment, the methacrylic monomer includes methacrylic acid (MAA), 2-phenoxyethyl methacrylate (PEMA), and hydroxybutyl methacrylate (HBMA). The acrylic monomer includes 4-tert-butylcyclohexyl acrylate (TBCHA).

[0045] Methacrylic acid (4 carbons) is low in cost and has high adhesion, effectively improving the adhesion of polymer resins. 2-Phenoxyethyl methacrylate (12 carbons) has a high glass transfer temperature, and the presence of a benzene ring enhances the rigidity of polymer resins. Hydroxybutyl methacrylate (8 carbons) provides hydrophobicity through its aliphatic backbone, and its hydroxyl groups can subsequently crosslink with the curing agent. The addition of tert-butylcyclohexyl acrylate (13 carbons) reduces the surface tension of polymer resins, improves adhesion, and also offers advantages such as low odor and high solubility, thereby preventing bubble formation and improving the adhesion of the protective film to the substrate.

[0046] In the above exemplary embodiments, the monomer with the highest number of carbon atoms is tert-butylcyclohexyl acrylate (the first monomer), and the monomer with the second highest number of carbon atoms is 2-phenoxyethyl methacrylate (the second monomer). Therefore, the molar ratio of 2-phenoxyethyl methacrylate to tert-butylcyclohexyl acrylate is 0.15 to 6.

[0047] If the total weight of the monomers in the synthetic polymer resin is 100% by weight, the content of methacrylic acid is 3% to 6% by weight, the content of 2-phenoxyethyl methacrylate is 8% to 60% by weight, the content of hydroxybutyl methacrylate is 20% to 30% by weight, and the content of tert-butylcyclohexyl acrylate is 10% to 60% by weight.

[0048] The curing agent can be selected from epoxy compounds, amine compounds, and isocyanate compounds, with isocyanate compounds being preferred. Preferably, the curing agent is a polyisocyanate curing agent manufactured by Yusheng Technology, such as, but not limited to, isocyanate curing agent U5. Polyisocyanate curing agents have good solubility in organic solvents, and their highly polar isocyanate groups (N-HCO) can wet the adherend or form strong hydrogen bonds and dipole attraction, increasing adhesion to the substrate.

[0049] The epoxy compounds may be selected from the group consisting of diethanol glycidyl ether, polyethylene glycol diglycidyl ether, glyceryl diglycidyl ether, glyceryl triglycidyl ether, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl m-phenylenediamine, N,N,N',N'-tetraglycidylaminobenzyl methane, triglycidyl triisocyanate, m-N,N-diglycidylaminophenyl glycidyl ether, N,N-diglycidyl toluidine, and N,N-diglycidyl aniline.

[0050] The amine compounds can be selected from the group consisting of free hexamethylenediamine, triethylenediamine, polyethyleneimine, hexamethylenetetramine, diethylenetriamine, triethylenetetramine, isophoronediamine, amine resins, and methylene resins.

[0051] Isocyanate compounds can be selected from isocyanate monomers, isocyanate compounds, triisocyanates, and biuret-type compounds. The isocyanate monomers for synthesizing the curing agent can be selected from the group consisting of toluene diisocyanate, chlorophenyl diisocyanate, hexamethylene diisocyanate, tetramethylethylene diisocyanate, isophorone diisocyanate, phenyl dimethyl diisocyanate, diphenylmethane diisocyanate, and hydrogenated diphenylmethane diisocyanate. The curing agent in the adhesive composition can be an isocyanate curing agent.

[0052] The adhesive composition may also include a curing accelerator. The curing accelerator may be a Lewis base, such as one or more of imidazole, boron trifluoride amine complex, ethyltriphenylphosphine chloride, 2-methylimidazole, 2-phenyl-imidazole, 2-ethyl-4-methylimidazole, triphenylphosphine, and 4-dimethylaminopyridine. The curing accelerator may also be a Lewis acid, such as a metal salt compound. Specifically, the curing accelerator may be a metal salt compound containing manganese, iron, cobalt, nickel, copper, or zinc, such as zinc octoate, cobalt octoate, cobalt acetylacetonate, or zinc acetylacetonate. The curing accelerator may also be a metal salt compound accelerator, such as a compound in which aluminum, iron, copper, zinc, cadmium, cobalt, lead, tin, titanium, nickel, antimony, magnesium, vanadium, chromium, or zirconium metal is coordinated in acetylacetonate or ethyl acetoacetate, or an organic acid salt such as a metal acetate, octate, naphthenate, or laurate, preferably aluminum acetylacetonate.

[0053] Experimental test results show that the preferred curing accelerator is a metal zirconia compound accelerator, which has advantages such as fast curing speed, immediate bridging effect after drying, small performance deviation, and non-yellowing. In some embodiments, the amount of metal zirconia compound accelerator added is 0.4 to 0.5 parts by weight relative to 100 parts by weight of polymer resin.

[0054] The antistatic agent in the adhesive composition can be an ionic or nonionic antistatic agent. Ionic antistatic agents can be quaternary ammonium salts, tertiary ammonium salts, or carboxylates. Through the addition of the antistatic agent and the provision of the conductive layer 2, the antistatic protective film of the present invention can have a low peeling electrostatic force, thus preventing integrated circuits from being electrostatically damaged.

[0055] The solvent in the adhesive composition may be ethyl acetate, but the present invention is not limited thereto.

[0056] [Preparation Example 1]

[0057] In a flask equipped with a condenser and a stirrer, add 0.1 parts by weight of azobisisobutyronitrile (ADVN) (initiator), 180 parts by weight of propylene glycol methyl ether acetate (PGMEA) (solvent), 8.6 parts by weight of methacrylic acid (MAA), 20.6 parts by weight of 2-phenoxyethyl methacrylate (PEMA) (second monomer), 47.4 parts by weight of hydroxybutyl methacrylate (HBMA), and 105 parts by weight of tert-butylcyclohexyl acrylate (TBCHA) (first monomer).

[0058] After continuously purging nitrogen to maintain a nitrogen atmosphere inside the flask, stirring and heating were started. The temperature of the flask was maintained at 65°C for 6.5 hours to obtain the polymer resin of Preparation Example 1. The monomer amounts used to synthesize the polymer resin, the molar ratio of the second monomer to the first monomer, and the weight-average molecular weight of the polymer resin are listed in Table 1.

[0059] [Preparation Examples 2 to 6]

[0060] Preparation Examples 2 to 6 were prepared in a manner similar to Preparation Example 1, except that the molar ratio of the second monomer to the first monomer was different. The monomer amounts, molar ratios of the second monomer to the first monomer, and weight-average molecular weights of the polymer resins synthesized in Preparation Examples 2 to 6 are listed in Table 1.

[0061] Table 1

[0062]

[0063] As can be seen from the results in Table 1, the weight-average molecular weight of the polymer resin of the present invention is from 450,000 g / mol to 600,000 g / mol. For example, the weight-average molecular weight of the polymer resin can be a positive integer between 450,000 g / mol and 600,000 g / mol.

[0064] [Example 1]

[0065] Weigh out 2 parts by weight of poly(3,4-dioxyethylthiophene):polystyrene sulfonic acid (PEDOT:PSS) (model: VERAZOL). TM WED-SM was coated onto a 38-micron-thick polyethylene terephthalate film (carrier layer) and dried in a 110°C hot air oven for one minute to generate a 0.3-micron-thick conductive layer.

[0066] Weigh 100 parts by weight of the polymer resin from Preparation Example 1, add 8.5 parts by weight of curing agent (U5 polyisocyanate curing agent produced by Yousheng Technology), 0.5 parts by weight of aluminum acetylacetonate (B5 accelerator produced by Yousheng Technology), 2 parts by weight of nonionic antistatic agent (Cantistater-570) (antistatic agent) and 100 parts by weight of ethyl acetate (solvent), and stir to mix to obtain the adhesive composition of the present invention.

[0067] An adhesive composition is coated onto a polyethylene terephthalate (PET) film with a conductive layer, and dried in a hot air oven at 110°C for two minutes to form an adhesive layer with a thickness of 20 micrometers. Another PET film (release layer) with a surface tension of 40 to 60 dynes / cm is then bonded onto the adhesive layer to form a laminated structure. A release agent layer is coated on the PET film of the release layer.

[0068] The laminated structure was kept at 25°C for seven days to cure the adhesive layer and obtain the antistatic protective film of Example 1 (e.g. Figure 3 (The structure shown).

[0069] The component ratios in the adhesive composition of Example 1 (E1) and the performance evaluation of the antistatic protective film are listed in Table 2.

[0070] For the part where the film is applied evenly, after applying the protective film to the silicon wafer surface using a 1 kg roller, observe whether air bubbles are generated between the protective film and the silicon wafer. A "○" indicates no air bubbles are generated on the surface, while an "X" indicates air bubbles (more than ten bubbles).

[0071] In the residual adhesive assessment section, a 1 kg roller is used to apply the protective film to the surface of the silicon wafer, which is then removed. The surface of the silicon wafer is then observed for any residual adhesive. A mark “○” indicates that there is no residual adhesive on the silicon wafer surface.

[0072] In the section on stripping electrostatic voltage, after the protective film is attached to the wafer using a 1 kg roller, an electrostatic meter (manufacturer: Keyence Corporation, model: SK-H050) is used to measure the voltage (electrostatic voltage) generated by the protective film when it is peeled off at a peeling speed of 30 meters / minute. The measured peeling value is taken as the stripping electrostatic voltage.

[0073] Regarding the surface resistivity, the antistatic protective film was placed in an environment of 23°C and 50% relative humidity for seven days or one month after application. After removing the antistatic protective film, the surface resistivity of the adhesive layer was measured using a resistivity meter (model: Keysight E2985B).

[0074] For peel strength testing, a 25 mm wide protective film was applied to a stainless steel sheet, silicon wafer, or gold-plated substrate using a 1 kg roller. The peel strength of the protective film was measured at a peel speed of 0.3 m / min in a 180° direction using a tensile testing machine. Additionally, the same 25 mm wide protective film was applied to the same stainless steel sheet, silicon wafer, or gold-plated substrate using the same method, and after being left at room temperature (25°C) for one month, the peel strength was measured again under the same operating conditions.

[0075] [Examples 2 to 4]

[0076] The protective films of Examples 2 to 4 were prepared in a manner similar to that of Example 1, the difference being the use of different polymer resins. The component ratios in the adhesive compositions of Examples 2 to 4 (E2 to E4) and the property evaluation of the protective films are listed in Table 2.

[0077] [Examples 5, 8 to 10]

[0078] The protective films of Examples 5, 8 to 10 were prepared sequentially in a manner similar to that of Examples 1 to 4, the difference being that conductive layers (such as conductive layers on both sides of the carrier layer) were provided. Figure 1 (Structure shown). The component ratios in the adhesive compositions of Examples 5, 8 to 10 (E5, E8 to E10) and the evaluation of the properties of the protective film are listed in Table 2.

[0079] [Examples 6 and 7]

[0080] The protective films of Examples 6 and 7 were prepared in a manner similar to that of Example 1, except for the amount of curing agent added. The component ratios in the adhesive compositions of Examples 6 and 7 (E6 to E7) and the evaluation of the properties of the protective films are listed in Table 2.

[0081] [Comparative Examples 1 and 2]

[0082] The protective films of Comparative Examples 1 and 2 were prepared in a manner similar to that of Example 1, except that the polymer resins used were different. The component ratios in the adhesive compositions of Comparative Examples 1 and 2 (C1 to C2) and the property evaluation of the protective films are listed in Table 2.

[0083] [Comparative Example 3]

[0084] The protective film of Comparative Example 3 was prepared in a manner similar to that of Example 1, except that no conductive layer was formed. The component ratios in the adhesive composition of Comparative Example 3 (C3) and the performance evaluation of the protective film are listed in Table 2.

[0085] Table 2

[0086]

[0087]

[0088] Table 2 (continued)

[0089]

[0090]

[0091] According to the results in Table 2 (Comparative Examples 1 and 2), controlling the molar ratio of the second monomer to the first monomer to be between 0.15 and 6 can improve the smoothness of the antistatic protective film after application, and the adhesive layer can have superior adhesion durability without leaving any residue on the substrate. Specifically, after prolonged use, the antistatic protection can still maintain a peel strength higher than 88% of the original peel strength.

[0092] According to the results in Table 2 (Comparative Example 3), the addition of a conductive layer can reduce the peel voltage and surface resistance of the antistatic protective film. The antistatic effect is best when the carrier layer is a double-sided conductive carrier layer, resulting in lower surface resistance. When the carrier layer is a single-sided conductive carrier layer, the peel voltage can be between 0.60 kV and 0.80 kV, and the surface resistance can reach 2.5 × 10⁻⁶. 10 Up to 5.5×10 10 When the carrier layer is a double-sided conductive carrier layer, the stripping static voltage can be from 0.50kV to 0.55kV, and the surface resistivity can reach 2.0×10⁻⁶. 9 Up to 8.0×10 9 .

[0093] On the other hand, in terms of the peel strength of the protective film, the peel strength of the protective film on stainless steel sheets can be 105gf / 25mm to 140gf / 25mm, the peel strength of the protective film on silicon wafers can be 100gf / 25mm to 130gf / 25mm, and the peel strength of the protective film on gold-plated substrates can be 105gf / 25mm to 130gf / 25mm.

[0094] [Beneficial Effects of the Examples]

[0095] One of the beneficial effects of the present invention is that the antistatic protective film and adhesive composition provided by the present invention can achieve good adhesion smoothness and adhesion durability when the antistatic protective film is applied to the substrate by means of the technical solutions of "the molar ratio of the second monomer to the first monomer is 0.15 to 6" and "the carbon number of the acrylic monomer is higher than the carbon number of the methacrylic acid monomer".

[0096] The content disclosed above is only a preferred and feasible embodiment of the present invention, and is not intended to limit the scope of protection of the claims of the present invention. Therefore, all equivalent technical changes made based on the content of the present invention specification and drawings are included within the scope of protection of the claims of the present invention.

Claims

1. An adhesive composition, characterized in that, The adhesive composition comprises: 100 parts by weight of a polymer resin, wherein the monomers for synthesizing the polymer resin include a first monomer and a second monomer, wherein the first monomer is the monomer with the highest carbon number among the monomers for synthesizing the polymer resin, and the second monomer is the monomer with the second highest carbon number among the monomers for synthesizing the polymer resin, and the molar ratio of the second monomer to the first monomer is 0.15 to 6; wherein the monomers for synthesizing the polymer resin include an acrylic acid monomer and a methacrylic acid monomer, wherein the acrylic acid monomer has a higher carbon number than the methacrylic acid monomer; 3 to 15 parts by weight of a curing agent; 0.2 to 3 parts by weight of an accelerator; and 0.5 to 5 parts by weight of an antistatic agent.

2. The adhesive composition according to claim 1, characterized in that, The methacrylic acid monomer has 4 to 12 carbon atoms, and the acrylic acid monomer has 13 to 20 carbon atoms.

3. The adhesive composition according to claim 1, characterized in that, The first monomer is the acrylic acid monomer, and the second monomer is the methacrylic acid monomer.

4. The adhesive composition according to claim 1, characterized in that, The polymer resin has a weight-average molecular weight of 450,000 g / mol to 600,000 g / mol.

5. The adhesive composition according to claim 1, characterized in that, The methacrylic acid monomers include methacrylic acid, 2-phenoxyethyl methacrylate, and hydroxybutyl methacrylate.

6. The adhesive composition according to claim 5, characterized in that, The total weight of the monomers used to synthesize the polymer resin is 100% by weight, the content of methacrylic acid is 3% to 6% by weight, the content of 2-phenoxyethyl methacrylate is 8% to 60% by weight, and the content of hydroxybutyl methacrylate is 20% to 30% by weight.

7. The adhesive composition according to claim 1, characterized in that, The acrylic monomer includes tert-butylcyclohexyl acrylate.

8. The adhesive composition according to claim 7, characterized in that, The total weight of the monomers used to synthesize the polymer resin is 100% by weight, and the content of tert-butylcyclohexyl acrylate is from 10% to 60% by weight.

9. The adhesive composition according to claim 1, characterized in that, The curing agent is a polyisocyanate curing agent.

10. The adhesive composition according to claim 1, characterized in that, The accelerator is a metal complex.

11. The adhesive composition according to claim 1, characterized in that, The accelerator is aluminum acetylacetonate.

12. The adhesive composition according to claim 1, characterized in that, The antistatic agent is a nonionic antistatic agent.

13. An antistatic protective film, characterized in that, The antistatic protective film includes: One load-bearing layer; A conductive layer; An adhesive layer, which is formed from the adhesive composition according to any one of claims 1 to 12; and One release layer; The adhesive layer is disposed between the carrier layer and the release layer, and the conductive layer is disposed on at least one surface of the carrier layer.

14. The antistatic protective film according to claim 13, characterized in that, The surface tension of the release layer is 40 dynes / cm to 60 dynes / cm.

15. The antistatic protective film according to claim 13, characterized in that, The conductive layer is formed from poly(3,4-dioxyethylthiophene):polystyrene sulfonic acid.

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