Protective film for polarizing plate

A protective film for the polarizing plate, comprising a base material and an auxiliary layer, a protective film for the polarizing plate wherein in analysis of bonding state of carbon atom (C1s) employing X-ray photoelectron spectroscopy, when a peak having the lowest bonding energy is designated as a first peak, a peak positioned at 1.60±0.3 eV on the higher bonding energy side from the first peak is designated as a second peak, and a peak positioned at 4.10±0.3 eV on the higher bonding energy side from the first peak is designated as a third peak, bonding state of carbon atom C1s on a surface of at least one side of the auxiliary layer and bonding state of internal carbon atom C1s of the auxiliary layer in an optional depth of 0.05 to 1 μm from the surface satisfy relationship described below:

• S′−I′≧0.1
• wherein S′ is intensity of the second peak on the auxiliary layer surface of the protective film for the polarizing plate/intensity of the first peak on the auxiliary layer surface of the protective film for the polarizing plate, and I′ is intensity of the second peak in the interior of the auxiliary layer of the protective film for the polarizing plate/intensity of the first peak of the interior of the auxiliary layer of the protective film for the polarizing plate.

A protective film for a polarizing plate, comprising a base material wherein at least one surface of the base material is subjected to plasma treatment.

A protective film for a polarizing plate, comprising a base material and an auxiliary layer, wherein the surface of the auxiliary layer is subjected to plasma treatment.

A polarizing plate, comprising a first protective film, polarizer and a second protective film, wherein at least one of the first protective film and the second protective film comprises a base material, and in analysis of bonding state of a carbon atom employing X-ray photoelectron spectroscopy, when a peak having the lowest bonding energy is designated as a first peak, a peak positioned at 1.60±0.3 eV on the higher bonding energy side from the first peak is designated as a second peak, and a peak positioned at 4.10±0.3 eV on the higher bonding energy side from the first peak is designated as a third peak, bonding state of carbon atom C1s on the surface of at least one side of the base material and bonding state of internal carbon atom C1s in an optional depth of 0.05 to 1 μm from the surface satisfy relationship described below:

• S−I≧0.1
• wherein S is intensity of the second peak on the base material surface intensity of the first peak on the base material surface, and I is intensity of the second peak in the interior of the base material intensity of the first peak of the interior of the base.

A production method of a protective film for a polarizing plate, comprising the following steps, and a step in which a prepared film is subjected to plasma treatment.

A production method of a polarizing plate comprising following steps:

• a step in which the surface of a polarizer or a surface of a protective film for the polarizing plate is subjected to plasma treatment, and
• a step in which the protective film subjected to plasma treatment for the polarizing plate is adhered with at least one of polarizer surfaces or a protective film for the polarizing plate is at least one of polarizer surfaces subjected to plasma treatment.