Method for manufacturing resin substrate with hard coating film and resin substrate with hard coating film

1. A method for manufacturing a resin substrate with a hard coating film having a resin substrate formed by injection molding, a resin film on one main surface of the resin substrate and a hard coating film including at least a primer layer and a hard coating layer laminated on the resin film, the method comprising:

a step (1) of preparing the resin film with a thickness of 150 to 400 μm and made of a same kind of resin as a resin constituting the resin substrate, applying a primer layer forming composition containing a primer resin component containing an acrylic polymer (A) having a mass average molecular weight of 200,000 to 1,000,000 as a main component and a solvent by a wet method on one main surface of the resin film and drying the primer layer forming composition to form the primer layer having a content of the solvent of less than 1.5 mass % relative to 100 mass % of a total solid content, to obtain a resin film laminate;

a step (2) of forming the resin substrate by injection molding on another main surface of the resin film in the resin film laminate, to obtain a resin substrate with a resin film laminate; and

a step (3) of applying a hard coating layer forming composition containing an organopolysiloxane (S) as a main component on the primer layer in the resin substrate with a resin film laminate and curing the hard coating layer forming composition, to obtain the resin substrate with a hard coating film.

2. The manufacturing method according to claim 1 , wherein the resin constituting the resin substrate and the resin film is polycarbonate.

3. The manufacturing method according to claim 1 ,

wherein the primer layer forming composition contains a non-polymerizable ultraviolet absorbent, and a content of the ultraviolet absorbent is 5 to 50 mass % relative to 100 mass % of the primer resin component.

4. The manufacturing method according to claim 1 ,

wherein the organopolysiloxane (S) contains: an organopolysiloxane (a) containing silicon-containing bond units represented by following T1 to T3 at a ratio among numbers of the units of T1:T2:T3=0 to 5:30 to 45:50 to 70 and a ratio of T3/T2≥1.5, and having a ratio of the number of hydroxyl groups (Hy) bonded to silicon atoms relative to the number of alkoxy groups (Al) bonded to silicon atoms in a molecule, (Hy)/(Al) of 12.0 to 100 on a molecular average, and a mass average molecular weight of 800 to 8,000; and an organopolysiloxane (b) having silicon-containing bond units represented by the following T1 to T3 and having a mass average molecular weight of 1/10 to 1/1.5 times the mass average molecular weight of the organopolysiloxane (a) at a ratio of 100 to 500 mass % relative to 100 mass % of the organopolysiloxane (a),

T1: R—Si(—OX) 2 (—O*—)

T2: R—Si(—OX)(—O*—) 2

T3: R—Si(—O*—) 3

where R represents an alkyl group having 1 to 6 carbon atoms, X represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and O* represents an oxygen atom linking two silicon atoms.

5. The manufacturing method according to claim 1 , wherein the application of the hard coating layer forming composition in the step (3) is performed by a flow coating method.

6. The manufacturing method according to claim 1 , wherein the application of the hard coating layer forming composition in step (3) is performed by a wet method.