TWI897477B - Composite film for protecting components and manufacturing method thereof - Google Patents

Abstract

The present invention is a composite film for protecting a device and a method for manufacturing the same. The method comprises providing a substrate; a pressure-sensitive adhesive solution comprising a first (meth) acrylic polymer, a second (meth) acrylic polymer, a hardener, and a solvent. The first (meth) acrylic polymer and the second (meth) acrylic polymer have hydroxyl groups. The first (meth) acrylic polymer has a Tg temperature of -80 to 0°C, and the second (meth) acrylic polymer has a Tg temperature of -80 to 0°C. The polymer has a Tg temperature of 0-150°C and a molecular weight of 1000-10000 g/mole. The weight ratio of the first (meth)acrylic polymer to the second (meth)acrylic polymer in the pressure-sensitive adhesive solution is 5:95-25:75. The pressure-sensitive adhesive solution is applied to the substrate and baked at 80-120°C for 5-30 minutes to form a pressure-sensitive adhesive film. A release layer is then applied to the pressure-sensitive adhesive film. The composite film produced using this manufacturing method exhibits no adhesion to components at room temperature, adheres perfectly to components after rapid pressing, and leaves no adhesive residue or contamination when removed after the high-temperature hot pressing process.

Description

Composite film for protecting components and its manufacturing method

This invention relates to a composite film for protecting components and its manufacturing method, particularly a composite film for protecting components during high-temperature hot pressing processes. The composite film's pressure-sensitive adhesive film exhibits no adhesion to components at room temperature, adheres perfectly to components after rapid pressing, and leaves no adhesive residue or contamination when the composite film is removed after the high-temperature hot pressing process.

In recent years, electronic products have been trending toward lighter, thinner, shorter, and smaller designs. These products are required to possess a wide range of functions and be integrated into a single electronic or circuit component. As the distance between circuit components' contacts decreases, the number of wires required increases, and the length of wiring between points is locally shortened, high-density wiring configurations are necessary.

Fundamentally, achieving high-density circuit configuration on single- or double-sided boards is difficult with current technology, forcing related electronic products to move towards multi-layer board designs.

Generally speaking, multi-layer boards are manufactured using a well-known build-up method. This involves applying a high-temperature hot press process to the appropriate sheets, films, and copper foils. This process is then repeated to add layers, completing the multi-layer board. However, this build-up method involves multiple high-temperature hot presses. Without a laminate film to protect the circuitry during the process, the existing circuit layers can oxidize and become damaged during these multiple high-temperature hot presses.

For laminate films used to protect components, in addition to withstanding high-temperature hot-pressing processes and being easily removable afterward, they must also be free of adhesive residue and pollution. Furthermore, the pressure-sensitive adhesive layer of the laminate must address step differences, protect through-hole resist, and provide a smooth hot-pressing surface. Furthermore, to ensure ease of handling before the high-temperature hot-pressing process, the pressure-sensitive adhesive layer of the laminate is expected to be non-adhesive to the substrate at room temperature and easily secure to the substrate after the rapid pressing process.

There are many types of laminated film products on the market today. The most common pressure-sensitive adhesives for laminated films are silicone-based pressure-sensitive adhesives or silicone resins. However, these types of films often leach silicone oil, contaminating the substrate and exhibiting a slight stickiness at room temperature, making them difficult to handle. Another common type of pressure-sensitive adhesive for laminated films is made from UV-curable resins or UV-curable pressure-sensitive adhesives. These films adhere easily to the substrate before high-temperature hot pressing, and then undergo UV curing using UV equipment after the high-temperature process, achieving easy-to-peel properties. However, using UV irradiation not only increases the cost of UV equipment but also complicates the process. Furthermore, due to their design, UV-curable materials have poor heat resistance, which can lead to the risk of adhesive residue during subsequent high-temperature hot pressing. Another type of material is fluorine-based resins, which, due to their low surface energy, often exhibit poor adhesion during rapid pressing and raise environmental concerns.

In view of this, there is still room for improvement in the existing technology for producing multi-layer panels using high-temperature hot pressing processes for composite films.

The present invention provides a composite film for protecting a device and a method for manufacturing the same. The composite film comprises: a pressure-sensitive adhesive solution comprising a first (meth)acrylic polymer, a second (meth)acrylic polymer, a hardener, and a solvent. The first (meth)acrylic polymer and the second (meth)acrylic polymer have hydroxyl groups. The first (meth)acrylic polymer has a Tg temperature of -80°C to 0°C, and the second (meth)acrylic polymer has a Tg temperature of -80°C to 0°C. The Tg temperature of the composite is 0-150°C, and its molecular weight is selected to be 1000-10000 g/mole. The weight ratio of the first (meth)acrylic polymer to the second (meth)acrylic polymer in the pressure-sensitive adhesive solution is 5:95-25:75. The pressure-sensitive adhesive solution is applied to the substrate and baked at 80-120°C for 5-30 minutes to form a pressure-sensitive adhesive film. A release layer is then provided and attached to the pressure-sensitive adhesive film. The composite film produced by this manufacturing method exhibits no adhesion to components at room temperature, adheres perfectly to components after rapid pressing, and leaves no adhesive residue or contamination when removed after the high-temperature hot pressing process.

To further understand the features and technical contents of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings are provided for reference and illustration only and are not intended to limit the present invention.

12: Composite film

14: Base material

16: Pressure-sensitive film

18: Exfoliation layer

19: Objects to be attached

20:Substrate

22: First Surface

24: Second Surface

26: Components

28: Component surface

Figure 1 is a first schematic diagram of the composite film for protecting components and its manufacturing method according to the present invention.

Figure 2 is a second schematic diagram of the composite film for protecting components and its manufacturing method according to the present invention.

Figure 3 is a third schematic diagram of the composite film for protecting components and its manufacturing method according to the present invention.

Figure 4 is a fourth schematic diagram of the composite film for protecting components and its manufacturing method according to the present invention.

Please refer to FIG1 . The composite film and its manufacturing method for protecting components of the present invention include a composite film 12, which includes a substrate 14; a pressure-sensitive adhesive solution, which includes a first (meth) acrylic polymer, a second (meth) acrylic polymer, a hardener, and a solvent. The first (meth) acrylic polymer and the second (meth) acrylic polymer have hydroxyl groups. The Tg temperature of the first (meth) acrylic polymer is -80 to 0°C, and the Tg temperature of the second (meth) acrylic polymer is 0 to 1°C. The pressure-sensitive adhesive solution is prepared by coating the substrate 14 with a first (meth)acrylic polymer and a second (meth)acrylic polymer at a temperature of 50°C and a molecular weight of 1,000 to 10,000 g/mole. The weight ratio of the first (meth)acrylic polymer to the second (meth)acrylic polymer is 5:95 to 25:75. The pressure-sensitive adhesive solution is applied to the substrate 14 and baked at 80°C to 120°C for 5 to 30 minutes to form a pressure-sensitive adhesive film 16. A release layer 18 is then provided and attached to the pressure-sensitive adhesive film 16. The release layer 18 is subsequently removed from the pressure-sensitive adhesive film 16 when the substrate is to be attached.

Referring to Figure 2 , the object 19 includes a substrate 20 and a component 26 . The substrate 20 includes a first surface 22 and a second surface 24 . The component 26 is disposed on the first surface 22 of the substrate and includes a component surface 28 .

Referring to Figure 3, a pressure-sensitive adhesive film 16 is attached to the first surface 22 of the substrate 20 and the component surface 28 via a rapid pressing process at 80-120°C for 10-60 seconds. The process then undergoes a high-temperature hot pressing process at 150-220°C for 30-240 minutes.

Please refer to Figure 4. After the high-temperature hot-pressing process is completed, the pressure-sensitive adhesive film 16 is removed and the first surface 22 of the substrate 20 and the device surface 28 are inspected for contamination and adhesive residue.

The substrate 20 is used as a support for the pressure-sensitive adhesive film 16. Its thickness can be between 5 and 300 micrometers (μm), preferably between 12.5 and 200 μm.

In the present invention, the substrate is not particularly limited, as long as the substrate 20 can withstand the temperature and pressure under the selected high-temperature hot-pressing conditions without losing its protective effect. In the embodiments and comparative examples of the present invention, polyimide (PI) is used as the substrate for the composite film.

Furthermore, the substrate 20 can be surface treated to achieve a close bond with other layers. For example, the substrate 20 can be subjected to physical treatment, chemical treatment, or both. Treatment methods may include light treatment, coma discharge, undercoat treatment, coating treatment, crosslinking treatment, chromic acid treatment, ozone exposure, flame exposure, high-voltage electric shock exposure, and ionizing radiation treatment.

The first and second (meth)acrylic polymers herein are polymers obtained by polymerizing a monomer component containing at least a (meth)acrylic ester as a polymerizable monomer, and have at least structural units derived from a (meth)acrylic ester. In this specification, the term "(meth)acrylic" encompasses both "acrylic" and "methacrylic." Similarly, the term "(meth)acrylate" encompasses both "acrylate" and "methacrylate."

Examples of (meth)acrylates include alkyl (meth)acrylates, hydroxyalkyl (meth)acrylates, alkoxyalkyl (meth)acrylates, aralkyl (meth)acrylates, and aryl (meth)acrylates, as well as other (meth)acrylates. The (meth)acrylates may be used singly or in combination of two or more.

The polymerization of monomers to form polymers requires the use of an initiator, such as 2,4-dichlorobenzyl peroxide, tert-butyl peroxyvalerate, benzoyl peroxide, methylbenzoyl phosphine peroxide, bis-3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, tert-butyl peroxy-2-ethylhexanoate, cyclohexanone peroxide, methyl ethyl ketone peroxide, dicumyl peroxide, lauryl peroxide, diisopropylbenzene hydroperoxide, tert-butyl hydroperoxide, and oil-soluble organic peroxides such as tert-butyl peroxide, or oil-soluble azo compounds such as 2,2'-azobisisobutyronitrile, 2,2'-azobis(2,4-dimethylvaleronitrile), and 2,2'-(2,4-dimethyl-4-methoxyvaleronitrile). The oil-soluble polymerization initiator is preferably an oil-soluble azo compound. The oil-soluble polymerization initiator can be used alone or in combination of two or more.

In general known technology, in order to increase the cohesive force of the pressure-sensitive adhesive film 16, a polyisocyanate-based hardener is also added. For example, the polyisocyanate-based hardener can be toluene diisocyanate (TDI), isophorone diisocyanate (IPDI), diphenylmethane diisocyanate (MDI), dicyclohexylmethane diisocyanate (HMDI), lysine diisocyanate (LDI) or related derivatives, and the derivatives can also be high-molecular isocyanates or isocyanate oligomers. To achieve the desired degree of hardening of the first (meth)acrylic polymer and the second (meth)acrylic polymer, the isocyanate or its derivative is mixed in an appropriate ratio. However, it is generally understood that optimizing the degree of hardening depends on various formulations, compositions, and compatibility. In the present embodiment, the hardener is toluene diisocyanate (TDI), and the isocyanate content is preferably 5-15% based on 100% by weight of the pressure-sensitive adhesive solution, for example, 5%, 6%, 7%, 8%, 9%, ..., or 15%.

The solvent is used to dissolve the monomer mixture and the initiator, imparting an appropriate viscosity to the (meth)acrylic polymer solution. The solvent does not interfere with the polymerization reaction and can prevent transesterification with the various monomers. Examples of the solvent include ethyl acetate, toluene, and butanone. Ethyl acetate, toluene, and butanone are also solvents used to prepare pressure-sensitive adhesive solutions.

The pressure-sensitive adhesive solution of the present invention comprises a first (meth)acrylic polymer, a second (meth)acrylic polymer, a hardener, and a solvent. The first (meth)acrylic polymer and the second (meth)acrylic polymer have hydroxyl groups. The first (meth)acrylic polymer has a Tg temperature of -80°C to 0°C, the second (meth)acrylic polymer has a Tg temperature of 0°C to 150°C, and the molecular weight is selected to be 1000 to 10000 g/mole. The pressure-sensitive adhesive film 16 is formed by coating the adhesive solution with a first (meth)acrylic polymer and a second (meth)acrylic polymer in a weight ratio of 5:95 to 25:75. The method for forming the pressure-sensitive adhesive film 16 is not particularly limited and can be applied by any known method. After coating the adhesive film 16 to a desired thickness on a substrate 20 and drying it to form the pressure-sensitive adhesive film 16, the first and second (meth)acrylic polymers react with a hardener and are then aged. The aging conditions are preferably 23°C to 70°C for one to seven days. Coating can be done using a coating machine such as a doctor blade coater, roller blade coater, gravure coater, die coater, curtain coater, notch wheel coater, lip coater, etc.

In the present invention, the thickness of the pressure-sensitive adhesive film 16 can be in the range of 5 to 100 micrometers (μm). In practice, to ensure the physical properties of the protective film, the pressure-sensitive adhesive film 16 must have a thickness greater than 5 μm.

A release layer 18 can be disposed on the surface of the pressure-sensitive adhesive film 16, such that the pressure-sensitive adhesive film 16 is disposed between the substrate 20 and the release layer 18. The release layer 18 can have a thickness between 10 and 200 microns (μm) and can be formed from paper, polyethylene, polypropylene, or polyethylene terephthalate. Since the release layer 18 is a known material, it is not limited here. The release layer 18 provides protection and isolation for the acrylic pressure-sensitive adhesive film, preventing the release layer 18 from being affected by environmental factors and altering its physical properties during storage.

The substrate 20 and component 26 are the substrate 19. Common materials for substrate 20 include bakelite, fiberglass, and various plastic sheets. PCB manufacturers typically use an insulating pre-impregnated material composed of fiberglass non-woven material and epoxy resin, which is then pressed with copper foil to create a copper foil substrate.

During the manufacturing process of copper-clad laminates, single-sided and double-sided printed circuit boards, components are obtained by selectively performing hole processing, chemical copper plating, electrolytic copper plating, etching, and other processes on the substrate material - copper-clad laminates.

The pressure-sensitive adhesive film 16 of the composite film of the present invention can be completely adhered to the component 26 during the rapid pressing process. The temperature and pressure selected for the rapid pressing process are not particularly limited. Generally speaking, the rapid pressing temperature is usually 80-120°C, such as 85°C, 100°C, or 120°C. The rapid pressing pressure can be approximately 10-50 kg/cm², such as 20, 30, 40, or 50 kg/cm². The rapid pressing duration can be 10 to 60 seconds, such as 10, 20, 30, or 40 seconds.

The pressure-sensitive adhesive film 16 of the composite film of the present invention can be applied to the desired location of an object 19, which may include a component 26 and a portion of the first surface 22 of the substrate 20, to provide heat-resistant protection. The temperature and pressure selected for the high-temperature hot pressing process are determined by the hot pressing conditions set by the user and are not particularly limited. Generally speaking, the high-temperature hot pressing temperature is typically 150 to 220°C, such as 150°C, 160°C, or 220°C. The high-temperature hot pressing pressure can be approximately 5 to 80 kg/cm², such as 5, 15, 25, or 80 kg/cm². The high-temperature hot pressing duration can be 30 to 240 minutes, such as 30 minutes, 60 minutes, 120 minutes, or 240 minutes.

The composite film provided by the present invention can have various shapes. Specifically, the composite film can be a sheet of adhesive material or a rolled adhesive material. Furthermore, the shape of the composite film can be adjusted based on the application, the type of product to be adhered, or other manufacturing process parameters, and the present invention is not limited thereto.

The composite film of the present invention may further include other ingredients commonly used in composite films to achieve other effects as needed. The commonly used ingredients include but are not limited to ingredients selected from the following groups: antistatic agents, chelating agents, flame retardants (such as phosphorus-containing flame retardants or bromine-containing flame retardants), polymerization promoters, fillers, dispersants (such as silane coupling agents), toughening agents, and combinations thereof. These ingredients can be used alone or in combination according to actual needs. For example, a polymerization promoter, such as a Lewis acid or an imidazole promoter, can be added to provide time control and improve the curing effect of the subsequent high-temperature hot pressing process; or a filler selected from the following group can be added to adjust the processability, flame retardancy, heat resistance, moisture resistance and other properties of the protective film: silicon dioxide, glass powder, and the aforementioned combination. There is no particular limitation on the dosage of the components commonly used in composite films. Those skilled in the art can adjust the dosage according to actual needs.

The following examples and comparative examples will demonstrate the content and effects of the composite film for protecting components and its manufacturing method provided by the present invention.

The first (meth)acrylic polymer and the second (meth)acrylic polymer of the pressure-sensitive adhesive solution were purchased from Hsin Chung Industrial Co., Ltd. The selected models and mixing weight ratios are described in the following examples and comparative examples.

According to the requirements of the embodiments and comparative examples of the present invention, different Tg temperatures, molecular weights, and hydroxyl values are selected and mixed in appropriate proportions.

Tg (°C) Measurement Method: The Tg temperatures of the first and second (meth)acrylic polymers were measured using a differential scanning calorimeter (DSC). The Tg temperature was determined as the midpoint of the DSC curve where straight lines extending from each baseline at equal distances in the longitudinal direction intersect the curve representing the glass transition phase. Apparatus: Differential scanning calorimeter (DSC 204 F1, manufactured by NETZSCH Instruments, Germany), nitrogen atmosphere, heating rate: 10°C/min, measurement temperature range: -100°C to 180°C.

Molecular weight (g/mole) measurement method: The molecular weight of the second (meth)acrylic polymer was measured using gel permeation chromatography (GPC). 0.1 g of the sample was dissolved in 10 ml of tetrahydrofuran. The dissolved sample was then subjected to GPC molecular weight measurement. The result is the weight average molecular weight.

Hydroxyl value (mgKOH/g) measurement method: The hydroxyl value of the second (meth) acrylic polymer was measured by titration. (1) Acetylation agent preparation: Weigh 42g of phthalic anhydride and dissolve it in 300mL of dried pyridine. After complete dissolution, store it in a brown bottle and place it in a desiccator for later use. (2) Acylation catalyst selection: Weigh 6g of imidazole and add it to the prepared acetylation agent. (3) Analytical procedure: Accurately weigh a certain amount of sample on an analytical balance and place it in an acetylation bottle with a condenser. Use a pipette to accurately add 25 mL of acetylation agent. After the sample is dissolved, place it in a constant temperature water bath. Acetylation reaction takes 20 to 25 minutes. After removing from the water bath, cool to room temperature. Add 20 mL (1:1) pyridine distillate aqueous solution from the upper edge of the condenser to hydrolyze the remaining anhydride. After shaking, add 3 to 5 drops of phenolphthalein indicator. Titrate with 0.8 or 1 mol/L KOH standard solution until pink. The end point is when the color does not change for 15 seconds. Perform a blank test in the same way. The hydroxyl value is calculated as follows, with an allowable error of less than 0.5 mg KOH/g. Hydroxyl value = (volume of KOH solution consumed in blank - volume of KOH solution consumed in sample) × KOH concentration × 56.1 / sample size (g)

Hardener (wt%): Add an appropriate amount (as in the example) of 5-15% polyisocyanate hardener (toluene diisocyanate, CAS number: 584-84-9, purchased from Sigma-Aldrich) to the total weight of the first (meth)acrylate polymer and the second (meth)acrylate polymer.

The preparation and proportion of the pressure-sensitive adhesive solution are described in detail in the Examples and Comparative Examples. The resulting pressure-sensitive adhesive solution was coated onto a 25μm-thick polyimide (PI) film that had been subjected to a corona treatment using a coating machine. The film was then dried in a dryer at 90°C for 30 minutes to obtain a 20μm-thick pressure-sensitive adhesive film.

Use a hand roller to laminate the pressure-sensitive adhesive film 16 onto the release layer 18 to create a composite film.

A. Observation of the adhesion of the pressure-sensitive adhesive film 16 to the substrate 19 at room temperature: First, clean the first surface 22 of the substrate 20 and the component surface 28 with a dust-free cloth moistened with alcohol and acetone and leave for one hour. Then, cut the laminate into 1-inch x 20-cm pieces, remove the release layer, and adhere them to the first surface of the substrate and the component surface. 180° peel adhesion was tested using a universal material testing machine in accordance with ASTM D1000. If the test data is 0 gf/inch, it is considered non-adhesive. The substrate and component are the substrate and the component, with the substrate being a simple PCB and the component being the circuitry on the PCB.

B. Adhesion of the pressure-sensitive adhesive film 16 of the laminate to the substrate 19 after rapid pressing: First, clean the first surface 22 of the substrate 20 and the component surface 28 with a dust-free cloth moistened with alcohol and acetone and allow to stand for one hour. The laminate was then cut into 1-inch x 20-cm squares, and the release layer 18 was removed. The laminate was then attached to the first surface 22 of the substrate 20 and the component surface 28. After rapid pressing at 100°C, a pressure of 30 kg/cm², and a duration of 10 seconds, the 180° peel adhesion test was performed using a universal material testing machine in accordance with ASTM D1000. If the test value is >0 gf/inch and no bubbles are observed visually from a distance of 30 cm from the substrate 19, the laminate was considered fully adhered.

C. Glue residue on the first surface 22 of the substrate 20 and the component surface 28 after hot pressing: First, the samples that were determined to be fully bonded after the rapid pressing process were subjected to hot pressing at a temperature of 170°C, a pressure of 40 kg/cm², and a duration of 240 minutes. The pressure-sensitive adhesive film 16 of the composite film was then peeled off from the first surface 22 of the substrate 20 and the component surface 28. The bonded surface of the component 26 was then observed under a microscope (magnification: 400X) to determine if there was any residual adhesive.

Example 1:

The first (meth)acrylic polymer (model: HT-111, viscosity: 5000-8000 cps, solids content: 30%) had a Tg of -73°C as measured by DSC. The second (meth)acrylic polymer (model: LT-461, viscosity: 1000-3000 cps, solids content: 45%) had a Tg of 76°C as measured by DSC, a molecular weight of 5528 g/mole as measured by GPC, and a hydroxyl group value of 93 mgKOH/g as measured by titration. The first (meth)acrylic polymer and the second (meth)acrylic polymer were diluted in ethyl acetate to a solids content of 20% in a flask at a weight ratio of 15:85. A hardener (10 wt%) was added and stirred thoroughly to obtain the pressure-sensitive adhesive solution. The pressure-sensitive adhesive solution was applied to polyimide (PI) using a doctor blade and baked at 90°C for 30 minutes to form a 20μm pressure-sensitive adhesive film. The pressure-sensitive adhesive film was then laminated to the release layer using a hand roller to create a composite film.

Example 2:

The first (meth)acrylic polymer (model: HT-215, viscosity: 8000-10000 cps, solids content: 30%) had a Tg of -6°C as measured by DSC. The second (meth)acrylic polymer (model: LT-461, viscosity: 1000-3000 cps, solids content: 45%) had a Tg of 74°C as measured by DSC, a molecular weight of 5611 g/mole as measured by GPC, and a hydroxyl group value of 91 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Example 3:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -38°C as measured by DSC. The second (meth)acrylic polymer (model: LT-162, viscosity: 12000-18000 cps, solids content: 60%) had a Tg of 141°C as measured by DSC, a molecular weight of 5688 g/mole as measured by GPC, and a hydroxyl group value of 90 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Example 4:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -42°C as measured by DSC. The second (meth)acrylic polymer (model: LT-441, viscosity: 3000-5000 cps, solids content: 30%) had a Tg of 1°C as measured by DSC, a molecular weight of 5716 g/mole as measured by GPC, and a hydroxyl group value of 91 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Example 5:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -39°C as measured by DSC. The second (meth)acrylic polymer (model: LT-095, viscosity: 10000-15000 cps, solids content: 40%) had a Tg of 78°C as measured by DSC, a molecular weight of 9953 g/mole as measured by GPC, and a hydroxyl group value of 90 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Example 6:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -38°C as measured by DSC. The second (meth)acrylic polymer (model: LT-481, viscosity: 1000-3000 cps, solids content: 30%) had a Tg of 73°C as measured by DSC, a molecular weight of 1106 g/mole as measured by GPC, and a hydroxyl group value of 89 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Example 7:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -46°C as measured by DSC. The second (meth)acrylic polymer (model: LT-304, viscosity: 3000-6000 cps, solids content: 30%) had a Tg of 74°C as measured by DSC. GPC had a molecular weight of 5432 g/mole, and a hydroxyl group value of 141 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Example 8:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -41°C as measured by DSC. The second (meth)acrylic polymer (model: LT-494, viscosity: 3000-6000 cps, solids content: 50%) had a Tg of 72°C as measured by DSC, a molecular weight of 5518 g/mole as measured by GPC, and a hydroxyl group value of 42 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Example 9:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -39°C as measured by DSC. The second (meth)acrylic polymer (model: LT-461, viscosity: 1000-3000 cps, solids content: 45%) had a Tg of 73°C as measured by DSC, a molecular weight of 5498 g/mole as measured by GPC, and a hydroxyl group value of 96 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Example 10:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -42°C as measured by DSC. The second (meth)acrylic polymer (model: LT-461, viscosity: 1000-3000 cps, solids content: 45%) had a Tg of 73°C as measured by DSC, a molecular weight of 5397 g/mole as measured by GPC, and a hydroxyl group value of 93 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Example 11:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -45°C as measured by DSC. The second (meth)acrylic polymer (model: LT-461, viscosity: 1000-3000 cps, solids content: 45%) had a Tg of 74°C as measured by DSC, a molecular weight of 5628 g/mole as measured by GPC, and a hydroxyl group value of 98 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Example 12:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -42°C as measured by DSC. The second (meth)acrylic polymer (model: LT-461, viscosity: 1000-3000 cps, solids content: 45%) had a Tg of 69°C as measured by DSC, a molecular weight of 5881 g/mole as measured by GPC, and a hydroxyl group value of 93 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Example 13:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -44°C as measured by DSC. The second (meth)acrylic polymer (model: LT-461, viscosity: 1000-3000 cps, solids content: 45%) had a Tg of 71°C as measured by DSC, a molecular weight of 5647 g/mole as measured by GPC, and a hydroxyl group value of 96 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Comparative example 1:

The first (meth)acrylic polymer (model: HT-156, viscosity: 2000-4000 cps, solids content: 35%) had a Tg of -98°C as measured by DSC. The second (meth)acrylic polymer (model: LT-461, viscosity: 1000-3000 cps, solids content: 45%) had a Tg of 72°C as measured by DSC. GPC had a molecular weight of 5587 g/mole, and a hydroxyl group value of 99 mgKOH/g as measured by titration. Mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Comparative example 2:

The first (meth)acrylic polymer (model: HT-564, viscosity: 2000-5000 cps, solids content: 35%) had a Tg of 7°C as measured by DSC. The second (meth)acrylic polymer (model: LT-461, viscosity: 1000-3000 cps, solids content: 45%) had a Tg of 71°C as measured by DSC, a molecular weight of 5683 g/mole as measured by GPC, and a hydroxyl group value of 98 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Comparative example 3:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -42°C as measured by DSC. The second (meth)acrylic polymer (model: LT-981, viscosity: 1000-3000 cps, solids content: 30%) had a Tg of -6°C as measured by DSC, a molecular weight of 5532 g/mole as measured by GPC, and a hydroxyl group value of 95 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Comparative example 4:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -44°C as measured by DSC. The second (meth)acrylic polymer (model: HT-132, viscosity: 15000-18000 cps, solids content: 45%) had a Tg of 158°C as measured by DSC, a molecular weight of 5492 g/mole as measured by GPC, and a hydroxyl group value of 94 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Comparative example 5:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -39°C as measured by DSC. The second (meth)acrylic polymer (model: LT-456, viscosity: 2000-3000 cps, solids content: 30%) had a Tg of 77°C as measured by DSC, a molecular weight of 953 g/mole as measured by GPC, and a hydroxyl group value of 91 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Comparative example 6:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -43°C as measured by DSC. The second (meth)acrylic polymer (model: LT-769, viscosity: 3000-5000 cps, solids content: 50%) had a Tg of 79°C as measured by DSC, a molecular weight of 11284 g/mole as measured by GPC, and a hydroxyl group value of 95 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Comparative example 7:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -48°C as measured by DSC. The second (meth)acrylic polymer (model: LT-131, viscosity: 4000-8000 cps, solids content: 30%) had a Tg of 77°C as measured by DSC, a molecular weight of 5679 g/mole as measured by GPC, and a hydroxyl group value of 32 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Comparative example 8:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -42°C as measured by DSC. The second (meth)acrylic polymer (model: LT-843, viscosity: 8000-11000 cps, solids content: 30%) had a Tg of 76°C as measured by DSC, a molecular weight of 5982 g/mole as measured by GPC, and a hydroxyl group value of 159 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Comparative example 9:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -39°C as measured by DSC. The second (meth)acrylic polymer (model: LT-461, viscosity: 1000-3000 cps, solids content: 45%) had a Tg of 76°C as measured by DSC, a molecular weight of 5713 g/mole as measured by GPC, and a hydroxyl group value of 99 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Comparative example 10:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -41°C as measured by DSC. The second (meth)acrylic polymer (model: LT-461, viscosity: 1000-3000 cps, solids content: 45%) had a Tg of 75°C as measured by DSC, a molecular weight of 5687 g/mole as measured by GPC, and a hydroxyl group value of 96 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Comparative example 11:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -38°C as measured by DSC. The second (meth)acrylic polymer (model: LT-461, viscosity: 1000-3000 cps, solids content: 45%) had a Tg of 69°C as measured by DSC, a molecular weight of 5813 g/mole as measured by GPC, and a hydroxyl group value of 95 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Comparative example 12:

The first (meth)acrylic polymer (model: HT-134, viscosity: 5000-7000 cps, solids content: 30%) had a Tg of -39°C as measured by DSC. The second (meth)acrylic polymer (model: LT-461, viscosity: 1000-3000 cps, solids content: 45%) had a Tg of 79°C as measured by DSC, a molecular weight of 5619 g/mole as measured by GPC, and a hydroxyl group value of 89 mgKOH/g as measured by titration. The mixing, dilution, hardener addition, composite film preparation method, and thickness were the same as in Example 1.

Comparison of Examples and Comparative Examples

Comparative Example 1: The Tg temperature of the first (meth)acrylic polymer is -98°C. The low Tg temperature makes the pressure-sensitive adhesive film softer, resulting in sticking.

Comparative Example 2: The Tg temperature of the first (meth)acrylic polymer is 7°C. The high Tg temperature makes the pressure-sensitive adhesive film hard, resulting in incomplete adhesion of the pressure-sensitive adhesive film.

Comparative Example 3: The Tg temperature of the second (meth)acrylic polymer is -6°C. The low Tg temperature makes the pressure-sensitive adhesive film softer, resulting in sticking.

Comparative Example 4: The Tg temperature of the second (meth)acrylic polymer is 158°C. The high Tg temperature makes the pressure-sensitive adhesive film hard, resulting in incomplete adhesion of the pressure-sensitive adhesive film.

Comparative Example 5: The second (meth)acrylic polymer has a molecular weight of 953 g/mole. This low molecular weight results in adhesive residue and sticking on the pressure-sensitive adhesive film.

Comparative Example 6: The molecular weight of the second (meth)acrylic polymer is 11284 g/mole. This high molecular weight results in a hard pressure-sensitive adhesive film, leading to incomplete adhesion.

Comparative Example 7: The second (meth)acrylic polymer has a hydroxyl value of 32 mgKOH/g. This low hydroxyl value results in a low degree of hardening of the pressure-sensitive adhesive film, leading to sticking.

Comparative Example 8: The second (meth)acrylic polymer has a hydroxyl value of 159 mgKOH/g. This high hydroxyl value results in a high degree of hardening of the pressure-sensitive adhesive film, resulting in incomplete adhesion.

Comparative Example 9: Mixing weight ratio: first (meth)acrylic polymer: second (meth)acrylic polymer = 2:98. Excessive amount of second (meth)acrylic polymer results in a high degree of hardening, resulting in incomplete adhesion.

Comparative Example 10: Mixing weight ratio: first (meth)acrylic polymer: second (meth)acrylic polymer = 30:70. The amount of the second (meth)acrylic polymer was too small, resulting in a low degree of curing and sticking.

Comparative Example 11: The hardener dosage is 3wt%. This dosage is too low, resulting in a low degree of hardening and residual adhesive.

Comparative Example 12: The hardener dosage was 17wt%. This excessive dosage resulted in a high degree of hardening and incomplete adhesion.

14: Base material

16: Pressure-sensitive film

19: Objects to be attached

20:Substrate

22: First Surface

24: Second Surface

26: Components

28: Component surface

Claims (10)

A method for manufacturing a composite film for protecting a device comprises: providing a substrate; providing a pressure-sensitive adhesive solution comprising a first (meth) acrylic polymer, a second (meth) acrylic polymer, a hardener, and a solvent, wherein the first (meth) acrylic polymer and the second (meth) acrylic polymer have hydroxyl groups, wherein the Tg temperature of the first (meth) acrylic polymer is -80 to 0°C, and the Tg temperature of the second (meth) acrylic polymer is -80 to 0°C. The polymer has a Tg temperature of 0-150°C and a molecular weight of 1,000-10,000 g/mole. The pressure-sensitive adhesive solution comprises a first (meth)acrylic polymer and a second (meth)acrylic polymer in a weight ratio of 5:95-25:75. The pressure-sensitive adhesive solution is applied to the substrate and baked at 80-120°C for 5-30 minutes to form a pressure-sensitive adhesive film. A release layer is then provided and attached to the pressure-sensitive adhesive film. The method for manufacturing a composite film for protecting a device as described in claim 1, wherein the curing agent is an isocyanate-based curing agent. As described in claim 1 of the patent application, in the method for manufacturing a composite film for protecting a device, the curing agent accounts for 5-15 wt% of the pressure-sensitive adhesive solution. The method for producing a composite film for protecting a device as described in claim 1, wherein the second (meth)acrylic polymer has a hydroxyl value of 40-145 mgKOH/g. The method for manufacturing a composite film for protecting a device as described in claim 1, wherein the solvent is selected from ethyl acetate, toluene, and butanone. A composite film for protecting components, the composite film being produced by the method described in item 1 of the patent application. As described in claim 6 of the composite film for protecting components, the hardener is an isocyanate-based hardener. As described in claim 6 of the composite film for protecting components, the hardener accounts for 5-15 wt% of the pressure-sensitive adhesive solution. The composite film for protecting a device as described in claim 6, wherein the second (meth)acrylic polymer has a hydroxyl value of 40-145 mgKOH/g. The composite film for protecting components as described in claim 6, wherein the solvent is selected from ethyl acetate, toluene, and butanone.