Liquid crystal display device and manufacturing method thereof

1. A manufacturing method of a liquid crystal display device having a liquid crystal layer between a pair of substrates, comprising:

disposing between the pair of substrates a liquid crystal composition which comprises liquid crystal molecules and a polymerizable compound that is polymerizable by active energy rays or a combination of active energy rays and heat, and

polymerizing the polymerizable compound by active energy ray irradiation, or by both active energy ray irradiation and heat with and/or without applying voltages to the liquid crystal layer, so that a polymer formed by the polymerizing process decides an alignment of the liquid crystal molecules when no voltage is applied,

wherein an amount of active energy ray irradiation is decided so that at least some of the polymerizable compound remains in the liquid crystal layer after the polymerization process, and further wherein the amount of the polymerizable compound that remains is not more than a predetermined value, and

wherein the amount of the polymerizable compound (A) is calculated by a following equation:

( A )=(a peak area of the polymerizable compound in gas chromatography after the polymerizing process)/(a peak area of the polymerizable compound in gas chromatography before the polymerizing process)×(an amount of polymerizable compound before the polymerizing process).

2. The manufacturing method of a liquid crystal display device according to claim 1 , wherein:

the predetermined value of the amount of the polymerizable compound is 0.05 parts by weight per 100 parts by weight of the liquid crystal layer.

3. The manufacturing method of a liquid crystal display device according to claim 1 , wherein:

the predetermined value of the amount of the polymerizable compound is 0.02 parts by weight per 100 parts by weight of the liquid crystal layer.

4. The manufacturing method of a liquid crystal display device according to claim 1 , wherein:

the amount of active energy ray irradiation is decided so that the amount of the polymerizable compound remaining in the liquid crystal layer immediately after the polymerization process is not more than the predetermined value.

5. The manufacturing method of a liquid crystal display device according to claim 1 , wherein:

the amount of active energy ray irradiation is decided so that the amount of the polymerizable compound remaining in the liquid crystal layer before use of the liquid crystal display is not more than 0.05 parts by weight per 100 parts by weight of the liquid crystal layer.

6. The manufacturing method of a liquid crystal display device according to claim 1 , wherein:

the amount of active energy ray irradiation is decided so that the amount of the polymerizable compound remaining in the liquid crystal layer before use of the liquid crystal display is not more than 0.02 parts by weight per 100 parts by weight of the liquid crystal layer.

7. A manufacturing method of a liquid crystal display device having a liquid crystal layer between a pair of substrates, comprising:

disposing between the pair of substrates a liquid crystal composition which comprises liquid crystal molecules and a polymerizable compound that is polymerizable by active energy rays or a combination of active energy rays and heat, and

polymerizing the polymerizable compound by active energy ray irradiation, or by both active energy ray irradiation and heat with and/or without applying voltages to the liquid crystal layer, so that a polymer formed by the polymerizing decides an alignment of liquid crystal molecules when no voltage is applied,

wherein the polymerizing process is performed until an amount of the polymerizable compound remaining in the liquid crystal layer is below a predetermined value, but wherein at least some of the polymerizable compound remains in the liquid crystal layer after the polymerizing process is performed, and

wherein the predetermined value of the amount of the polymerizable compound is decided so that an amount of the polymerizable compound before use of the liquid crystal device is not more than 0.05 parts by weight per 100 parts by weight of the liquid crystal layer.

8. The manufacturing method of a liquid crystal display device according to claim 7 , wherein:

the predetermined value of the amount of the polymerizable compound is decided so that an amount of the polymerizable compound before use of the liquid crystal device is not more than 0.02 parts by weight per 100 parts by weight of the liquid crystal layer.

9. A manufacturing method of a liquid crystal display device having a liquid crystal layer between a pair of substrates, comprising;

disposing between the pair of substrates a liquid crystal composition which comprises liquid crystal molecules and a polymerizable compound that is polymerizable by active energy rays or a combination of active energy rays and heat, and

polymerizing the polymerizable compound by active energy ray irradiation, or by both active energy ray irradiation and heat with and/or without applying voltages to the liquid crystal layer, so that a polymer formed by the polymerizing process decides an alignment of liquid crystal molecules when no voltage is applied,

wherein a condition of the polymerizing is decided in accordance with an amount of the polymerizable compound remaining in the liquid crystal layer after the polymerizing process value, but wherein at least some of the polymerizable compound remains in the liquid crystal layer after the polymerizing process is performed, and

wherein the predetermined value of the amount of the polymerizable compound is between 0.02 and 0.05 parts by weight per 100 parts by weight of the liquid crystal layer.

10. A manufacturing method of a liquid crystal display device having a liquid crystal layer between a pair of substrates, comprising:

disposing between the pair of substrates a liquid crystal composition which comprises liquid crystal molecules and a polymerizable compound that is polymerizable by active energy rays or a combination of active energy rays and heat,

polymerizing the polymerizable compound by active energy ray irradiation, or by both active energy ray irradiation and heat with and/or without applying voltages to the liquid crystal layer, so that a polymer formed by the polymerizing process decides an alignment of the liquid crystal molecules when no voltage is applied,

wherein an amount of active energy ray irradiation is decided so that an amount of the polymerizable compound remaining in the liquid crystal layer after the polymerization process is not more than a predetermined value, and

wherein the predetermined value of the amount of the polymerizable compound is between 0.02 and 0.05 parts by weight per 100 parts by weight of the liquid crystal layer.

11. A manufacturing method of a liquid crystal display device having a liquid crystal layer between a pair of substrates, comprising:

disposing between the pair of substrates a liquid crystal composition which comprises liquid crystal molecules and a polymerizable compound that is polymerizable by active energy rays or a combination of active energy rays and heat,

polymerizing the polymerizable compound by active energy ray irradiation, or by both active energy ray irradiation and heat with and/or without applying voltages to the liquid crystal layer, so that a polymer formed by the polymerizing process decides an alignment of the liquid crystal molecules when no voltage is applied,

wherein an amount of active energy ray irradiation is decided so that an amount of the polymerizable compound remaining in the liquid crystal layer after the polymerization process is not more than a predetermined value, and

wherein the amount of the polymerizable compound (A) is calculated by a following equation:

( A )=(a peak area of the polymerizable compound in gas chromatography after the polymerizing process)/(a peak area of the polymerizable compound in gas chromatography before the polymerizing process)×(an amount of polymerizable compound before the polymerizing process).

12. A manufacturing method of a liquid crystal display device having a liquid crystal layer between a pair of substrates, comprising:

disposing between the pair of substrates a liquid crystal composition which comprises liquid crystal molecules and a polymerizable compound that is polymerizable by active energy rays or a combination of active energy rays and heat,

polymerizing the polymerizable compound by active energy ray irradiation, or by both active energy ray irradiation and heat with and/or without applying voltages to the liquid crystal layer, so that a polymer formed by the polymerizing decides an alignment of liquid crystal molecules when no voltage is applied,

wherein the polymerizing process is performed until an amount of the polymerizable compound remaining in the liquid crystal layer is below a predetermined value, and

wherein the predetermined value of the amount of the polymerizable compound is decided so that an amount of the polymerizable compound before use of the liquid crystal device is not more than 0.05 parts by weight per 100 parts by weight of the liquid crystal layer.