Chris Rock is interviewed during the Toronto International Film Festival in Toronto, Ont., Monday, Sept. 14, 2009. Positive reviews have been rolling in for comedian Rock's documentary "Good Hair," a rollicking look at African-American hair culture.THE CANADIAN PRESS/Sean Kilpatrick

TORONTO - Positive reviews have been rolling in for comedian Chris Rock's documentary "Good Hair," a rollicking look at African-American hair culture.

But as far Rock is concerned, he's already secured the most important endorsement.

"My wife loved it," Rock told The Canadian Press during a recent interview in downtown Toronto. "She had a little dinner party, had a bunch of friends over to watch it. She ain't never done that.

"There was no 'Pootie Tang' party."

Of course, "Good Hair" - which opens in Canada on Friday after winning a Grand Jury prize at Sundance and screening last month at the Toronto International Film Festival - is no "Pootie Tang."

Rock has perhaps never made a movie that so clearly expresses his unique voice. Here, under the direction of stand-up comic Jeff Stilson, Rock delves into the complex issue of black hair care, a US$9 billion industry that reaches all around the world.

Mostly, that money is wrapped up in products and procedures designed to turn curly hair straight. Why? Well, as comedian Paul Mooney puts it in the film: "If your hair is relaxed, white people are relaxed. If your hair is nappy, they're not happy."

Still, Rock was surprised by the lengths to which people are going to get straight, silky hair, whether it involves massaging scalps with potentially blinding, destructive chemicals or pricey, high-maintenance weaves.

In the film, he dons goggles and a white lab coat as he explores a factory where hair relaxer - a thick lotion designed to smooth curls - is manufactured (while enthusiastically stirring an 8,000-kilogram vat of the stuff, he cracks: "This'd last Prince about a month!"), and he consults a chemist about the potential dangers of rubbing the mixture into one's scalp (the scientist demonstrates the chemical's destructive nature by using it to completely dissolve a can of Coke).

He also interviews regular working-class women in barbershops and salons in New York and L.A. who pay at least $1,000 every few months to have extensions woven into their hair.

And he coaxes exceedingly candid interviews from a slew of celebrities, including Maya Angelou, Nia Long, Ice-T, Rev. Al Sharpton, Raven-Symone, Eve and Toronto actress Melyssa Ford. The stars share their own hair-care procedures and some even divulge how much they spend on their locks.

How, exactly, did Rock persuade these stars to share such normally heavily fortified trade secrets?

"A lot of wine," he joked.

While the film affects a breezy tone - most of all during a trip to the annual Bronner Bros. International Hair Show in Atlanta, where he gleefully covers a hair-cutting competition in which hopefuls shear locks while underwater in an aquarium and hanging upside-down from a trapeze - Rock doesn't shy away from thorny political issues.

He examines why few of the businesses that cater to African-American hair care are actually black-owned and interviews a raucous group of men in a barbershop who talk about the way hair issues can strain a relationship.

And during a trip to India, where much of the "good hair" used to keep North American women in extensions is generated, the film documents religious ceremonies where women have their hair removed, only to have it scooped up and exported to the West by unscrupulous local businessmen.

"I'd never been to India," Rock said of the trip. "Dude, I've been to Africa a bunch of times, (and) Africa has so much less poverty than India. It's unbelievable."

Though Rock says he's had the idea for such a documentary since the early '90s, it was on the backburner - "a dream deferred," he says - until one of his young daughters, only five years old at the time, innocently asked him: "Daddy, how come I don't have good hair?"

It follows then that "Good Hair," which is by turns hilarious, tender and informative, is as much an examination of image and self-esteem as it is, specifically, about hair.

"There's something absurd about beautiful people wanting to be more beautiful," said Rock, wearing a green sweater with patches on the elbows, jeans and a pair of tan suede desert boots.

And that vanity afflicts everyone, he said.

"All people, all women," he added. "Everyone except the Swedes. They're beautiful. They look just right.

"They got the right look for success, those Swedes."

Rock's daughter isn't the only young child already concerned with her hair. During one section of the film, Rock interviews children as young as three years old (and their parents) who have received kiddie perms, using the same burning chemicals employed by adults.

While Rock's tone in the film is sympathetic and non-judgmental, he will say that he won't let his daughters undergo that treatment - for now, anyway.

"They're not going to have chemicals in their hair while they're young," he said. "I'm just not going there.

"But when they get older, they're going to do what they want to do. You're not going to stop a kid, a teenager, from having the hairstyle they want.

"You want to not know your kids when they're in their 20s and 30s? Yeah, dictate their hairstyle in their teens and watch what happens."

In fact, the 44-year-old - that caustic stand-up once named by Time Magazine the funniest man alive - remains remarkably sensitive during the film. While it's not hard to guess his viewpoint, he ultimately delivers the message that ultimately, all people need to feel good about themselves.

He shows the same gift for engaging an interview subject that he did on his beloved HBO series, "The Chris Rock Show." He displays his quick wit, yes, but more often he maintains a bemused demeanour and lets his interviewees get in the best lines.

In fact, one of the feats of "Good Hair" is showing just how much Rock has grown.

"I mean, you can judge (people), but it's such a women's issue, it didn't seem like a place to judge, you know what I mean?" he said.

"Being married and having daughters kind of softens you up from judgment. I'm just in a different place. If I didn't have daughters, I'd probably be like: 'What's going on?'